WO2019216100A1 - Rubber composition, foam rubber, tire tread, and tire - Google Patents

Abstract

The present invention addresses the problem of providing a rubber composition that can improve both wear resistance and performance on ice of a tire. The solution to this problem is a rubber composition characterized by comprising a rubber component (a) that contains a multicomponent copolymer (a1) containing a conjugated diene unit, a nonconjugated olefin unit, and an aromatic vinyl unit; and (b) a foaming agent.

Description

Rubber composition, foamed rubber, tire tread and tire

The present invention relates to a rubber composition, foamed rubber, tire tread and tire.

Conventionally, studless tires with softened tread rubber have been used as tires for safe driving on ice in addition to normal road surfaces. By softening the tread rubber, the on-ice performance of the tire can be improved. Are known. However, in general, a tire including a soft tread rubber has a problem of poor wear resistance on a normal road surface, and the performance on the ice and the wear resistance of the tire are in a trade-off relationship.
In addition, as a technique for improving the on-ice performance of a tire, for example, a technique for improving the on-ice performance of a tire by blending organic fiber, glass fiber, or the like with a rubber composition used for a tread and scratching an icy road surface is known. It has been. However, since organic fibers, glass fibers, and the like have no interaction with rubber, they function as fracture nuclei and cause a decrease in the fracture resistance (abrasion resistance) of the tread rubber.
As a rubber composition for tires that solves this problem, Japanese Patent Application Laid-Open No. 2008-303334 (Patent Document 1) discloses that potassium titanate fibers are added to 100 parts by weight of a rubber component composed of natural rubber and butadiene rubber. A rubber composition has been proposed in which 5 to 20 parts by weight and 5 to 200 parts by weight of carbon black having an iodine adsorption of 100 to 300 mg / g are blended, and the rubber composition is formed from a cap tread and a base tread. It has been reported that use on a cap tread of a tread having a two-layer structure improves the performance on ice (performance on ice and snow) while suppressing a decrease in wear resistance.

JP 2008-303334 A

However, as disclosed in Table 1 of Patent Document 1 above, by using a rubber composition containing a specific amount of potassium titanate fiber in the cap tread, the performance on ice of the tire (coefficient of friction on ice) is improved. The wear resistance is slightly lowered, and it is impossible to improve both the performance on ice and the wear resistance.

Then, this invention makes it a subject to solve the said problem of the said prior art and to provide the rubber composition which can improve both on-ice performance and abrasion resistance of a tire.
The present invention further provides a foamed rubber and a tire tread capable of improving both on-ice performance and wear resistance of a tire, and a tire excellent in both on-ice performance and wear resistance. It becomes the problem to become.

The gist configuration of the present invention for solving the above-described problems is as follows.

The rubber composition of the present invention includes a rubber component (a) containing a multi-component copolymer (a1) containing a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit,
A foaming agent (b);
It is characterized by containing.
By applying the rubber composition of the present invention to a tire, both the performance on ice and the wear resistance of the tire can be improved.

In the rubber composition of the present invention, the multi-component copolymer (a1) has a content of the conjugated diene unit of 1 to 50 mol%, a content of the non-conjugated olefin unit of 40 to 97 mol%, and the aromatic The group vinyl unit content is preferably 2 to 35 mol%. In this case, the wear resistance and weather resistance of the rubber composition are improved, and the wear resistance of the tire can be further improved by applying to the tire.

The rubber composition of the present invention preferably contains 0.5 to 50 parts by mass of the foaming agent (b) with respect to 100 parts by mass of the rubber component (a). In this case, the performance on ice and wear resistance of the tire can be further improved.

The rubber composition of the present invention preferably further contains hydrophilic short fibers (c). In this case, the on-ice performance of the tire can be greatly improved.

In the rubber composition of the present invention, the multi-component copolymer (a1) preferably has a melting point of 30 to 130 ° C. measured by a differential scanning calorimeter (DSC). In this case, the workability of the rubber composition is improved, and the wear resistance of the tire can be further improved by applying it to the tire.

In the rubber composition of the present invention, the multi-component copolymer (a1) preferably has an endothermic peak energy measured by a differential scanning calorimeter (DSC) at 0 to 120 ° C. of 10 to 150 J / g. In this case, the workability of the rubber composition is improved, and the wear resistance of the tire can be further improved by applying it to the tire.

In the rubber composition of the present invention, the multi-component copolymer (a1) preferably has a glass transition temperature of 0 ° C. or less as measured by a differential scanning calorimeter (DSC). In this case, workability of the rubber composition is improved.

In the rubber composition of the present invention, the multi-component copolymer (a1) preferably has a crystallinity of 0.5 to 50%. In this case, the workability of the rubber composition is improved, and the wear resistance of the tire can be further improved by applying it to the tire.

In the rubber composition of the present invention, the multi-component copolymer (a1) is preferably such that the non-conjugated olefin unit is an acyclic non-conjugated olefin unit. In this case, the weather resistance of the rubber composition is improved.

Here, it is more preferable that the non-cyclic non-conjugated olefin unit is composed of only ethylene units. In this case, the weather resistance of the rubber composition is further improved.

In the rubber composition of the present invention, it is preferable that in the multi-component copolymer (a1), the aromatic vinyl unit includes a styrene unit. In this case, the weather resistance of the rubber composition is improved.

In the rubber composition of the present invention, in the multi-component copolymer (a1), the conjugated diene unit preferably contains a 1,3-butadiene unit and / or an isoprene unit. In this case, the wear resistance of the tire can be further improved by applying it to the tire.

In a preferred example of the rubber composition of the present invention, the content of the multi-component copolymer (a1) in the rubber component (a) is 5 to 100% by mass. In this case, the wear resistance of the tire can be further improved by applying it to the tire.

The foamed rubber of the present invention is characterized by foaming the above rubber composition. By applying the foamed rubber of the present invention to a tire, both the performance on ice and the wear resistance of the tire can be improved.

The foamed rubber of the present invention preferably has a foaming rate of 5 to 80%. In this case, by applying to a tire, the performance on ice and the wear resistance of the tire can be further improved.

Further, the tire tread of the present invention is characterized by using the above foamed rubber. When the tire tread of the present invention is applied to a tire, both the performance on ice and the wear resistance of the tire can be improved.

Further, the tire of the present invention is characterized by using the above-described tire tread. Such a tire of the present invention is excellent in both on-ice performance and wear resistance.

ADVANTAGE OF THE INVENTION According to this invention, the rubber composition which can improve both the on-ice performance and abrasion resistance of a tire can be provided.
In addition, according to the present invention, it is possible to provide a foam rubber and a tire tread capable of improving both on-ice performance and wear resistance of a tire, and a tire excellent in both on-ice performance and wear resistance. Can do.

Hereinafter, the rubber composition, foamed rubber, tire tread, and tire of the present invention will be described in detail based on the embodiments.

<Rubber composition>
The rubber composition of the present invention comprises a rubber component (a) containing a multi-component copolymer (a1) containing a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit, and a foaming agent (b). , Containing.

By including the foaming agent (b), the rubber composition of the present invention forms bubbles derived from the foaming agent in the vulcanized rubber composition (foamed rubber), and uses the foamed rubber for a tire tread. Thus, the on-ice performance of the tire can be improved by the scratching effect and drainage effect of the tread bubbles.
Further, the multi-component copolymer (a1) contained in the rubber composition of the present invention contains a non-conjugated olefin unit, and when greatly distorted, the crystal component derived from the non-conjugated olefin unit collapses, Can dissipate energy. Therefore, the multi-component copolymer (a1) can suppress wear caused by large distortion by dissipating energy.
And since the rubber composition of this invention contains a multi-component copolymer (a1) with a foaming agent (b), since the distortion energy concerning the space | gap part produced by the bubble derived from a foaming agent (b) is dissipated. The wear resistance has been improved. Moreover, since the space | gap part produced by the bubble derived from a foaming agent (b) applies a big distortion locally, and the energy dissipation ability of a multicomponent copolymer (a1) is further demonstrated, a multicomponent with a foaming agent (b). Although the rubber composition of the present invention containing the copolymer (a1) contains the foaming agent (b), the wear resistance is greatly improved as compared with the rubber composition not containing the multi-component copolymer (a1). ing.
Therefore, when the rubber composition of the present invention is applied to a tire, both the performance on ice and the wear resistance of the tire can be improved.

The rubber component (a) of the rubber composition of the present invention includes a multi-component copolymer (a1) containing a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit. The multi-component copolymer (a1) contains at least a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit, and consists only of a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit. It may also contain other monomer units.

The conjugated diene unit is a structural unit derived from a conjugated diene compound as a monomer. The conjugated diene unit enables vulcanization of the multi-component copolymer and also exhibits elongation and strength as a rubber. Here, the conjugated diene compound refers to a conjugated diene compound. The conjugated diene compound preferably has 4 to 8 carbon atoms. Specific examples of the conjugated diene compound include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like. The conjugated diene compound may be a single kind or a combination of two or more kinds. The conjugated diene compound as a monomer of the multi-component copolymer is a 1,3-butadiene compound from the viewpoint of effectively improving the wear resistance of a rubber composition, a tire or the like using the obtained multi-component copolymer. And / or isoprene, more preferably 1,3-butadiene and / or isoprene alone, and still more preferably 1,3-butadiene alone. In other words, the conjugated diene unit in the multi-component copolymer preferably contains 1,3-butadiene units and / or isoprene units, and more preferably consists only of 1,3-butadiene units and / or isoprene units. Preferably, it consists only of 1,3-butadiene units.

In the multi-component copolymer (a1), the content of the conjugated diene unit is preferably 1 mol% or more, more preferably 3 mol% or more, and preferably 50 mol% or less, % Or less, more preferably 30 mol% or less, even more preferably 25 mol% or less, and even more preferably 15 mol% or less. When the content of the conjugated diene unit is 1 mol% or more of the entire multi-component copolymer, a rubber composition and a rubber product excellent in elongation can be obtained, and when it is 50 mol% or less, the weather resistance is excellent. In addition, the content of the conjugated diene unit is preferably in the range of 1 to 50 mol%, more preferably in the range of 3 to 40 mol%, based on the whole multi-component copolymer.

The non-conjugated olefin unit is a structural unit derived from a non-conjugated olefin compound as a monomer. When the non-conjugated olefin unit is largely distorted, the crystal component derived from the non-conjugated olefin unit is disintegrated to dissipate energy. Here, the non-conjugated olefin compound refers to a compound which is an aliphatic unsaturated hydrocarbon and has one or more carbon-carbon double bonds. The non-conjugated olefin compound preferably has 2 to 10 carbon atoms. Specific examples of such non-conjugated olefin compounds include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene and other α-olefins, vinyl pivalate, 1-phenylthioethene. And heteroatom-substituted alkene compounds such as N-vinylpyrrolidone. The non-conjugated olefin compound may be a single kind or a combination of two or more kinds. The non-conjugated olefin compound as a monomer of the multi-component copolymer is a non-cyclic non-conjugated olefin compound from the viewpoint of further improving the weather resistance of the rubber composition and the tire using the obtained multi-component copolymer. In addition, the acyclic non-conjugated olefin compound is more preferably an α-olefin, still more preferably an α-olefin containing ethylene, and particularly preferably only ethylene. In other words, the non-conjugated olefin unit in the multi-component copolymer is preferably an acyclic non-conjugated olefin unit, and the acyclic non-conjugated olefin unit is preferably an α-olefin unit. More preferably, it is more preferably an α-olefin unit containing an ethylene unit, and further preferably only an ethylene unit.

In the multi-component copolymer (a1), the content of the non-conjugated olefin unit is preferably 40 mol% or more, more preferably 45 mol% or more, and even more preferably 55 mol% or more, The amount is particularly preferably 60 mol% or more, more preferably 97 mol% or less, still more preferably 95 mol% or less, and still more preferably 90 mol% or less. If the content of the non-conjugated olefin unit is 40 mol% or more of the entire multi-component copolymer, the content of the conjugated diene unit or the aromatic vinyl unit is decreased as a result, the weather resistance is improved, Fracture resistance (particularly, breaking strength (Tb)) is improved. Further, when the content of the non-conjugated olefin unit is 97 mol% or less, the content of the conjugated diene unit or the aromatic vinyl unit increases as a result, and fracture resistance at high temperature (particularly, elongation at break (Eb)) Will improve. The content of the non-conjugated olefin unit is preferably in the range of 40 to 97 mol%, more preferably in the range of 45 to 95 mol%, and still more preferably in the range of 55 to 90 mol% with respect to the entire multi-component copolymer.

The aromatic vinyl unit is a structural unit derived from an aromatic vinyl compound as a monomer. The aromatic vinyl unit improves the workability of the multi-component copolymer. Here, the aromatic vinyl compound refers to an aromatic compound substituted with at least a vinyl group, and is not included in the conjugated diene compound. The aromatic vinyl compound preferably has 8 to 10 carbon atoms. Examples of such aromatic vinyl compounds include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, o, p-dimethylstyrene, o-ethylstyrene, m-ethylstyrene, p-ethylstyrene, and the like. . The aromatic vinyl compound may be a single type or a combination of two or more types. The aromatic vinyl compound as the monomer of the multi-component copolymer preferably contains styrene from the viewpoint of improving the weather resistance of the rubber composition and tires using the resulting multi-component copolymer. It is more preferable that it consists only of. In other words, the aromatic vinyl unit in the multi-component copolymer preferably includes a styrene unit, and more preferably includes only a styrene unit.
The aromatic ring in the aromatic vinyl unit is not included in the main chain of the multi-component copolymer unless it is bonded to an adjacent unit.

The multi-component copolymer (a1) preferably has a content of the aromatic vinyl unit of 2 mol% or more, more preferably 3 mol% or more, and preferably 35 mol% or less. It is still more preferably 30 mol% or less, and even more preferably 25 mol% or less. When the content of the aromatic vinyl unit is 2 mol% or more, the fracture resistance at high temperatures is improved. Moreover, the effect by a conjugated diene unit and a nonconjugated olefin unit becomes remarkable as content of an aromatic vinyl unit is 35 mol% or less. The content of the aromatic vinyl unit is preferably in the range of 2 to 35 mol%, more preferably in the range of 3 to 30 mol%, still more preferably in the range of 3 to 25 mol% with respect to the entire multi-component copolymer.

The number of types of monomers of the multi-component copolymer (a1) is not particularly limited as long as the multi-component copolymer contains a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit. The multi-component copolymer (a1) may have other structural units other than the conjugated diene unit, the non-conjugated olefin unit, and the aromatic vinyl unit, but the content of the other structural unit is desired. From the viewpoint of obtaining the above effect, it is preferably 30 mol% or less, more preferably 20 mol% or less, still more preferably 10 mol% or less, and not contained, that is, the content of the entire multi-component copolymer. Is particularly preferably 0 mol%.

The multi-component copolymer (a1) has a kind of conjugated diene compound, a kind of non-conjugated olefin compound, and a kind of aromatic as a monomer from the viewpoint of preferable wear resistance, weather resistance and crystallinity. A polymer obtained by polymerization using at least a vinyl compound is preferable. In other words, the multi-component copolymer (a1) is preferably a multi-component copolymer containing one kind of conjugated diene unit, one kind of non-conjugated olefin unit, and one kind of aromatic vinyl unit. More preferably, it is a terpolymer comprising only a conjugated diene unit, a non-conjugated olefin unit, and a single aromatic vinyl unit, and is composed only of a 1,3-butadiene unit, an ethylene unit, and a styrene unit. More preferably, it is a terpolymer. Here, the “one type of conjugated diene unit” includes conjugated diene units having different bonding modes.

In the rubber composition of the present invention, the multi-component copolymer (a1) has a content of the conjugated diene unit of 1 to 50 mol%, a content of the non-conjugated olefin unit of 40 to 97 mol%, and the aromatic The group vinyl unit content is preferably 2 to 35 mol%. In this case, the wear resistance and weather resistance of the rubber composition are further improved, and the wear resistance of the tire can be further improved by applying to the tire.

The multi-component copolymer (a1) preferably has a polystyrene-equivalent weight average molecular weight (Mw) of 10,000 to 10,000,000, more preferably 100,000 to 9,000,000. 150,000 to 8,000,000 is more preferable. When the Mw of the multi-component copolymer is 10,000 or more, the mechanical strength of the rubber composition can be sufficiently ensured, and when the Mw is 10,000,000 or less, high work is required. Sex can be maintained.

The multi-component copolymer (a1) preferably has a polystyrene-equivalent number average molecular weight (Mn) of 10,000 to 10,000,000, more preferably 50,000 to 9,000,000. More preferably, it is 100,000 to 8,000,000. When the Mn of the multi-component copolymer is 10,000 or more, sufficient mechanical strength of the rubber composition can be ensured, and when the Mn is 10,000,000 or less, high work can be achieved. Sex can be maintained.

The multi-component copolymer (a1) preferably has a molecular weight distribution [Mw / Mn (weight average molecular weight / number average molecular weight)] of 1.00 to 4.00, preferably 1.50 to 3.50. Is more preferable, and it is still more preferable that it is 1.80 to 3.00. If the molecular weight distribution of the multi-component copolymer is 4.00 or less, sufficient homogeneity can be brought about in the physical properties of the multi-component copolymer.

The above-mentioned weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw / Mn) are determined by gel permeation chromatography (GPC) using polystyrene as a standard substance.

In the rubber composition of the present invention, the multi-component copolymer (a1) preferably has a melting point measured by a differential scanning calorimeter (DSC) of 30 to 130 ° C., more preferably 30 to 110 ° C. . If the melting point of the multi-component copolymer (a1) is 30 ° C. or higher, the crystallinity of the multi-component copolymer (a1) is increased, the wear resistance of the rubber composition is further improved, and applied to a tire. The wear resistance of the tire can be further improved. Moreover, if the melting point of the multi-component copolymer (a1) is 130 ° C. or less, the workability of the rubber composition is improved.
Here, the melting point is a value measured by the method described in Examples.

In the rubber composition of the present invention, the multi-component copolymer (a1) preferably has an endothermic peak energy measured by a differential scanning calorimeter (DSC) at 0 to 120 ° C. of 10 to 150 J / g, preferably 30 to More preferably, it is 120 J / g. If the endothermic peak energy of the multi-component copolymer (a1) is 10 J / g or more, the crystallinity of the multi-component copolymer (a1) is increased, the wear resistance of the rubber composition is further improved, and it is applied to a tire. Thus, the wear resistance of the tire can be further improved. Moreover, if the endothermic peak energy of the multi-component copolymer (a1) is 150 J / g or less, the workability of the rubber composition is improved.
Here, the endothermic peak energy is a value measured by the method described in Examples.

In the rubber composition of the present invention, the multi-component copolymer (a1) preferably has a glass transition temperature (Tg) measured by a differential scanning calorimeter (DSC) of 0 ° C. or less, from −100 ° C. to −10 It is still more preferable that it is ° C. When the glass transition temperature of the multi-component copolymer (a1) is 0 ° C. or lower, the workability of the rubber composition is improved.
Here, the glass transition temperature is a value measured by the method described in Examples.

In the rubber composition of the present invention, the multi-component copolymer (a1) preferably has a crystallinity of 0.5 to 50%, more preferably 3 to 45%, and more preferably 5 to 45%. Even more preferably. If the degree of crystallinity of the multi-component copolymer (a1) is 0.5% or more, the crystallinity attributable to the non-conjugated olefin unit is sufficiently secured, and the wear resistance of the rubber composition is further improved, and the tire By applying to, the wear resistance of the tire can be further improved. In addition, when the crystallinity of the multi-component copolymer (a1) is 50% or less, workability during kneading of the rubber composition is improved, and a rubber composition containing the multi-component copolymer (a1) is blended. Since the tackiness of the rubber is improved, the workability when molding rubber products such as tires by attaching rubber members made from the rubber composition to each other is also improved.
Here, the crystallinity is a value measured by the method described in Examples.

In the rubber composition of the present invention, the multi-component copolymer (a1) preferably has a main chain consisting only of an acyclic structure. Thereby, the wear resistance of the rubber composition can be further improved, and by applying to a tire, the wear resistance of the tire can be further improved.
Incidentally, NMR is used as a main measuring means for confirming whether or not the main chain of the multi-component copolymer (a1) has a cyclic structure. Specifically, when a peak derived from a cyclic structure existing in the main chain (for example, a peak appearing at 10 to 24 ppm for a three-membered ring to a five-membered ring) is not observed, the main chain of the multi-component copolymer is It shows that it consists only of an acyclic structure.

The multi-component copolymer (a1) can be produced through a polymerization process using a conjugated diene compound, a non-conjugated olefin compound, and an aromatic vinyl compound as monomers, and further, if necessary, a coupling process, washing You may pass through a process and other processes.
Here, in the production of the multi-component copolymer (a1), in the presence of a polymerization catalyst, only a non-conjugated olefin compound and an aromatic vinyl compound are added and polymerized without adding a conjugated diene compound. Is preferred. In particular, when using the catalyst composition described below, the conjugated diene compound is more reactive than the non-conjugated olefin compound and the aromatic vinyl compound, so that the non-conjugated olefin compound and / or in the presence of the conjugated diene compound. It is difficult to polymerize the aromatic vinyl compound. In addition, it is easy to polymerize the conjugated diene compound first, and then additionally polymerize the non-conjugated olefin compound and the aromatic vinyl compound later due to the characteristics of the catalyst.

As the polymerization method, any method such as a solution polymerization method, a suspension polymerization method, a liquid phase bulk polymerization method, an emulsion polymerization method, a gas phase polymerization method, and a solid phase polymerization method can be used. In addition, when a solvent is used for the polymerization reaction, such a solvent is not particularly limited as long as it is inert in the polymerization reaction, and examples thereof include toluene, cyclohexane, and normal hexane.

The polymerization process may be performed in one stage, or may be performed in two or more stages. The one-step polymerization process means all kinds of monomers to be polymerized, that is, conjugated diene compounds, non-conjugated olefin compounds, aromatic vinyl compounds, and other monomers, preferably conjugated diene compounds, non-conjugated. In this step, the olefin compound and the aromatic vinyl compound are polymerized by reacting simultaneously. The multi-stage polymerization process means that a polymer is formed by first reacting part or all of one or two kinds of monomers (first polymerization stage), and then the remaining kinds of monomers. Or a step of polymerizing by performing one or more stages (second polymerization stage to final polymerization stage) in which the remainder of the one or two kinds of monomers is added and polymerized. In particular, in the production of multi-component copolymers, it is preferable to carry out the polymerization process in multiple stages.

In the polymerization step, the polymerization reaction is preferably performed in an atmosphere of an inert gas, preferably nitrogen gas or argon gas. The polymerization temperature of the polymerization reaction is not particularly limited, but is preferably in the range of −100 ° C. to 200 ° C., for example, and can be about room temperature. The pressure for the polymerization reaction is preferably in the range of 0.1 to 10.0 MPa in order to sufficiently incorporate the conjugated diene compound into the polymerization reaction system. Also, the reaction time of the above polymerization reaction is not particularly limited and is preferably in the range of, for example, 1 second to 10 days, but can be appropriately selected depending on conditions such as the type of polymerization catalyst and polymerization temperature.
In the polymerization step of the conjugated diene compound, the polymerization may be stopped using a polymerization terminator such as methanol, ethanol, isopropanol or the like.

The polymerization process is preferably performed in multiple stages. More preferably, a first step of obtaining a polymerization mixture by mixing a first monomer raw material containing at least an aromatic vinyl compound and a polymerization catalyst, and a conjugated diene compound, a non-conjugated olefin compound, and It is preferable to carry out the second step of introducing the second monomer raw material containing at least one selected from the group consisting of aromatic vinyl compounds. Further, it is more preferable that the first monomer raw material does not contain a conjugated diene compound and the second monomer raw material contains a conjugated diene compound.

The first monomer raw material used in the first step may contain a non-conjugated olefin compound together with the aromatic vinyl compound. Moreover, the 1st monomer raw material may contain the whole quantity of the aromatic vinyl compound to be used, and may contain only one part. The non-conjugated olefin compound is contained in at least one of the first monomer raw material and the second monomer raw material.

The first step is preferably performed in an atmosphere of an inert gas, preferably nitrogen gas or argon gas, in the reactor. The temperature (reaction temperature) in the first step is not particularly limited, but is preferably in the range of −100 ° C. to 200 ° C., for example, and can be about room temperature. The pressure in the first step is not particularly limited, but is preferably in the range of 0.1 to 10.0 MPa in order to sufficiently incorporate the aromatic vinyl compound into the polymerization reaction system. The time spent in the first step (reaction time) can be appropriately selected depending on conditions such as the type of polymerization catalyst and reaction temperature. For example, when the reaction temperature is 25 to 80 ° C., 5 minutes A range of ˜500 minutes is preferred.

In the first step, the polymerization method for obtaining the polymerization mixture may be any method such as a solution polymerization method, a suspension polymerization method, a liquid phase bulk polymerization method, an emulsion polymerization method, a gas phase polymerization method, and a solid phase polymerization method. Can be used. Further, when a solvent is used for the polymerization reaction, such a solvent may be any inactive in the polymerization reaction, and examples thereof include toluene, cyclohexanone, normal hexane and the like.

The second monomer raw material used in the second step is a conjugated diene compound only, or a conjugated diene compound and a non-conjugated olefin compound, or a conjugated diene compound and an aromatic vinyl compound, or a conjugated diene compound or a non-conjugated olefin. It is preferable that they are a compound and an aromatic vinyl compound.
In addition, when the second monomer raw material includes at least one selected from the group consisting of a non-conjugated olefin compound and an aromatic vinyl compound in addition to the conjugated diene compound, these monomer raw materials are preliminarily used as a solvent or the like. After mixing together, it may be introduced into the polymerization mixture, or each monomer raw material may be introduced from a single state. Moreover, each monomer raw material may be added simultaneously, and may be added sequentially. In the second step, the method for introducing the second monomer raw material into the polymerization mixture is not particularly limited, but it is continuously added to the polymerization mixture by controlling the flow rate of each monomer raw material. It is preferable to perform (so-called metering). Here, when a monomer raw material that is a gas under the conditions of the polymerization reaction system (for example, ethylene as a non-conjugated olefin compound under the conditions of room temperature and atmospheric pressure) is used, the polymerization reaction system is used at a predetermined pressure. Can be introduced.

The second step is preferably performed in an atmosphere of an inert gas, preferably nitrogen gas or argon gas, in the reactor. The temperature (reaction temperature) in the second step is not particularly limited, but is preferably in the range of −100 ° C. to 200 ° C., for example, and can be about room temperature. When the reaction temperature is raised, the selectivity of cis-1,4 bond in the conjugated diene unit may be lowered. The pressure in the second step is not particularly limited, but is preferably in the range of 0.1 to 10.0 MPa in order to sufficiently incorporate monomers such as a conjugated diene compound into the polymerization reaction system. The time spent in the second step (reaction time) can be appropriately selected depending on conditions such as the type of polymerization catalyst and reaction temperature, but is preferably in the range of 0.1 hour to 10 days, for example.
In the second step, the polymerization reaction may be stopped using a polymerization terminator such as methanol, ethanol, or isopropanol.

Here, the polymerization step of the conjugated diene compound, the non-conjugated olefin compound, and the aromatic vinyl compound includes a step of polymerizing various monomers in the presence of one or more of the following components (A) to (F). It is preferable to include. In the polymerization step, it is preferable to use one or more of the following components (A) to (F) as catalyst components, but a catalyst composition comprising a combination of two or more of the following components (A) to (F): More preferably, it is used as
(A) Component: Rare earth element compound or reaction product of the rare earth element compound and Lewis base (B) Component: Organometallic compound (C) Component: Aluminoxane (D) Component: Ionic compound (E) Component: Halogen compound ( F) Component: substituted or unsubstituted cyclopentadiene (compound having a cyclopentadienyl group), substituted or unsubstituted indene (compound having an indenyl group), and substituted or unsubstituted fluorene (compound having a fluorenyl group) ) -Containing cyclopentadiene skeleton-containing compound (hereinafter, simply referred to as “cyclopentadiene skeleton-containing compound”)
Hereinafter, components (A) to (F) will be described in detail.

Examples of the rare earth element compound or a reaction product of the rare earth element compound and a Lewis base (component (A)) include a rare earth element compound having a rare earth element-carbon bond, or a reaction product of the rare earth element compound and a Lewis base (hereinafter referred to as a rare earth element compound). , Also referred to as “component (A-1)”), a rare earth element compound having no rare earth element-carbon bond, or a reaction product of the rare earth element compound and a Lewis base (hereinafter referred to as “component (A-2)”) Say).

［式中、Ｍは、ランタノイド元素、スカンジウム又はイットリウムを示し、Ｃｐ^Rは、それぞれ独立して無置換もしくは置換インデニルを示し、Ｒ^a～Ｒ^fは、それぞれ独立して炭素数１～３のアルキル基又は水素原子を示し、Ｌは、中性ルイス塩基を示し、ｗは、０～３の整数を示す］で表されるメタロセン錯体、及び下記一般式（ＩＩ）：

［式中、Ｍは、ランタノイド元素、スカンジウム又はイットリウムを示し、Ｃｐ^Rは、それぞれ独立して無置換もしくは置換インデニルを示し、Ｘ’は、水素原子、ハロゲン原子、アルコキシ基、チオラート基、アミノ基、シリル基又は炭素数１～２０の一価の炭化水素基を示し、Ｌは、中性ルイス塩基を示し、ｗは、０～３の整数を示す］で表されるメタロセン錯体、並びに下記一般式（ＩＩＩ）：

［式中、Ｍは、ランタノイド元素、スカンジウム又はイットリウムを示し、Ｃｐ^R'は、無置換もしくは置換シクロペンタジエニル、インデニル又はフルオレニルを示し、Ｘは、水素原子、ハロゲン原子、アルコキシ基、チオラート基、アミノ基、シリル基又は炭素数１～２０の一価の炭化水素基を示し、Ｌは、中性ルイス塩基を示し、ｗは、０～３の整数を示し、［Ｂ］^-は、非配位性アニオンを示す］で表されるハーフメタロセンカチオン錯体が挙げられる。 Examples of the component (A-1) include the following general formula (I):

[ ^Wherein , M represents a lanthanoid element, scandium or yttrium, Cp ^R each independently represents an unsubstituted or substituted indenyl group, and R ^a to R ^f each independently represents an alkyl having 1 to 3 carbon atoms. A group or a hydrogen atom, L represents a neutral Lewis base, w represents an integer of 0 to 3, and the following general formula (II):

[ ^Wherein , M represents a lanthanoid element, scandium or yttrium, Cp ^R each independently represents an unsubstituted or substituted indenyl group, and X ′ represents a hydrogen atom, a halogen atom, an alkoxy group, a thiolate group, an amino group. A silyl group or a monovalent hydrocarbon group having 1 to 20 carbon atoms, L represents a neutral Lewis base, w represents an integer of 0 to 3, and Formula (III):

[ ^Wherein , M represents a lanthanoid element, scandium or yttrium, Cp ^{R ′} represents an unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl, and X represents a hydrogen atom, a halogen atom, an alkoxy group, a thiolate group. , An amino group, a silyl group, or a monovalent hydrocarbon group having 1 to 20 carbon atoms, L represents a neutral Lewis base, w represents an integer of 0 to 3, and [B] ⁻ represents non- A metallocene cation complex represented by the formula:

In the metallocene complexes represented by the above general formulas (I) and (II), Cp ^R in the formula is unsubstituted indenyl or substituted indenyl. Cp ^R having an indenyl ring as a basic skeleton can be represented by C ₉ H _7-x R _x or C ₉ H _11-x R _x . Here, X is an integer of 0 to 7 or 0 to 11. In addition, each R is preferably independently a hydrocarbyl group or a metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of the metalloid of the metalloid group include germyl Ge, stannyl Sn, silyl Si, and the metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group of the metalloid group is It is the same. Specific examples of the metalloid group include a trimethylsilyl group. Specific examples of the substituted indenyl include 2-phenylindenyl, 2-methylindenyl and the like. Note that the two Cp ^Rs in the general formulas (I) and (II) may be the same or different from each other.

In the half metallocene cation complex represented by the above general formula (III), Cp ^{R ′} in the formula is unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl, and among these, unsubstituted or substituted indenyl It is preferable that

［式中、Ｒは水素原子、メチル基又はエチル基を示す。］ In the general formula (III), Cp ^{R ′} having the cyclopentadienyl ring as a basic skeleton is represented by C ₅ H _5-x R _x . Here, X is an integer of 0 to 5. In addition, each R is preferably independently a hydrocarbyl group or a metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of the metalloid of the metalloid group include germyl Ge, stannyl Sn, silyl Si, and the metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group of the metalloid group is It is the same. Specific examples of the metalloid group include a trimethylsilyl group. Specific examples of Cp ^{R ′} having a cyclopentadienyl ring as a basic skeleton include the following.

[Wherein, R represents a hydrogen atom, a methyl group or an ethyl group. ]

In the general formula (III), Cp ^{R ′} having the above indenyl ring as a basic skeleton is defined in the same manner as Cp ^{R in} the general formulas (I) and (II), and preferred examples thereof are also the same.

In the general formula (III), Cp ^{R ′} having the fluorenyl ring as a basic skeleton can be represented by C ₁₃ H _9-x R _x or C ₁₃ H _17-x R _x . Here, X is an integer of 0 to 9 or 0 to 17. In addition, each R is preferably independently a hydrocarbyl group or a metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of the metalloid of the metalloid group include germyl Ge, stannyl Sn, silyl Si, and the metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group of the metalloid group is It is the same. Specific examples of the metalloid group include a trimethylsilyl group.

The central metal M in the general formulas (I), (II) and (III) is a lanthanoid element, scandium or yttrium. The lanthanoid elements include 15 elements having atomic numbers of 57 to 71, and any of these may be used. Preferred examples of the central metal M include samarium Sm, neodymium Nd, praseodymium Pr, gadolinium Gd, cerium Ce, holmium Ho, scandium Sc, and yttrium Y.

The metallocene complex represented by the general formula (I) contains a silylamide ligand [—N (SiR ₃ ) ₂ ]. The R groups contained in the silylamide ligand (R ^a to R ^f in the general formula (I)) are each independently an alkyl group having 1 to 3 carbon atoms or a hydrogen atom. Further, it is preferable that at least one of R ^a to R ^f is a hydrogen atom. By making at least one of R ^a to R ^f a hydrogen atom, the synthesis of the catalyst is facilitated, and the bulk around silicon is reduced, so that non-conjugated olefin compounds and aromatic vinyl compounds are introduced. It becomes easy. From the same viewpoint, it is more preferable that at least one of R ^a to R ^c is a hydrogen atom and at least one of R ^d to R ^f is a hydrogen atom. Furthermore, the alkyl group is preferably a methyl group.

The metallocene complex represented by the general formula (II) contains a silyl ligand [—SiX ′ ₃ ]. X ′ contained in the silyl ligand [—SiX ′ ₃ ] is a group defined in the same manner as X in the general formula (III) described below, and preferred groups are also the same.

In the general formula (III), X is a group selected from the group consisting of a hydrogen atom, a halogen atom, an alkoxy group, a thiolate group, an amino group, a silyl group, and a monovalent hydrocarbon group having 1 to 20 carbon atoms. . Here, the halogen atom represented by X may be any of a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, but is preferably a chlorine atom or a bromine atom.

In the general formula (III), the alkoxy group represented by X is an aliphatic alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, or a tert-butoxy group; a phenoxy group 2,6-di-tert-butylphenoxy group, 2,6-diisopropylphenoxy group, 2,6-dineopentylphenoxy group, 2-tert-butyl-6-isopropylphenoxy group, 2-tert-butyl-6 -Aryloxy groups such as neopentylphenoxy group and 2-isopropyl-6-neopentylphenoxy group, and the like. Among these, 2,6-di-tert-butylphenoxy group is preferable.

In the general formula (III), the thiolate group represented by X is a thiomethoxy group, thioethoxy group, thiopropoxy group, thio n-butoxy group, thioisobutoxy group, thiosec-butoxy group, thiotert-butoxy group or the like Group thiolate group; thiophenoxy group, 2,6-di-tert-butylthiophenoxy group, 2,6-diisopropylthiophenoxy group, 2,6-dineopentylthiophenoxy group, 2-tert-butyl-6-isopropyl And arylthiolate groups such as thiophenoxy group, 2-tert-butyl-6-thioneopentylphenoxy group, 2-isopropyl-6-thioneopentylphenoxy group, 2,4,6-triisopropylthiophenoxy group, etc. Among these, 2,4,6-triisopropylthiophenoxy Group is preferred.

In the general formula (III), the amino group represented by X is an aliphatic amino group such as a dimethylamino group, a diethylamino group or a diisopropylamino group; a phenylamino group, a 2,6-di-tert-butylphenylamino group, 2 , 6-diisopropylphenylamino group, 2,6-dineopentylphenylamino group, 2-tert-butyl-6-isopropylphenylamino group, 2-tert-butyl-6-neopentylphenylamino group, 2-isopropyl- Examples thereof include arylamino groups such as 6-neopentylphenylamino group, 2,4,6-tri-tert-butylphenylamino group; bistrialkylsilylamino groups such as bistrimethylsilylamino group. An amino group is preferred.

In the general formula (III), examples of the silyl group represented by X include trimethylsilyl group, tris (trimethylsilyl) silyl group, bis (trimethylsilyl) methylsilyl group, trimethylsilyl (dimethyl) silyl group, triisopropylsilyl (bistrimethylsilyl) silyl group, and the like. Among these, a tris (trimethylsilyl) silyl group is preferable.

In the general formula (III), as the monovalent hydrocarbon group having 1 to 20 carbon atoms represented by X, specifically, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, Linear or branched aliphatic hydrocarbon groups such as isobutyl, sec-butyl, tert-butyl, neopentyl, hexyl and octyl; aromatic hydrocarbons such as phenyl, tolyl and naphthyl Groups; aralkyl groups such as benzyl groups, etc .; hydrocarbon groups containing silicon atoms such as trimethylsilylmethyl groups, bistrimethylsilylmethyl groups, etc., among these, methyl groups, ethyl groups, isobutyl groups, trimethylsilylmethyl Groups etc. are preferred.

In general formula (III), X is preferably a bistrimethylsilylamino group or a monovalent hydrocarbon group having 1 to 20 carbon atoms.

In the general formula (III), [B] ^- The non-coordinating anion represented by, for example, a tetravalent boron anion. Specific examples of the tetravalent boron anion include tetraphenyl borate, tetrakis (monofluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluorophenyl) borate, tetrakis ( Pentafluorophenyl) borate, tetrakis (tetrafluoromethylphenyl) borate, tetra (tolyl) borate, tetra (xylyl) borate, (triphenyl, pentafluorophenyl) borate, [tris (pentafluorophenyl), phenyl] borate, tri Decahydride-7,8-dicarboundeborate is exemplified, and among these, tetrakis (pentafluorophenyl) borate is preferable.

The metallocene complex represented by the above general formulas (I) and (II) and the half metallocene cation complex represented by the above general formula (III) may further have 0 to 3, preferably 0 to 1, neutral Lewis Contains base L. Here, examples of the neutral Lewis base L include tetrahydrofuran, diethyl ether, dimethylaniline, trimethylphosphine, lithium chloride, neutral olefins, neutral diolefins, and the like. Here, when the complex includes a plurality of neutral Lewis bases L, the neutral Lewis bases L may be the same or different.

In addition, the metallocene complex represented by the general formulas (I) and (II) and the half metallocene cation complex represented by the general formula (III) may exist as a monomer, or a dimer. Or it may exist as a multimer more than that.

［式中、Ｘ’’はハライドを示す。］ The metallocene complex represented by the general formula (I) includes, for example, a lanthanoid trishalide, scandium trishalide or yttrium trishalide in a solvent, an indenyl salt (for example, potassium salt or lithium salt) and bis (trialkylsilyl). ) It can be obtained by reacting with an amine salt (for example, potassium salt or lithium salt). In addition, since reaction temperature should just be about room temperature, it can manufacture on mild conditions. The reaction time is arbitrary, but is about several hours to several tens of hours. The reaction solvent is not particularly limited, but is preferably a solvent that dissolves the raw material and the product. For example, toluene may be used. Below, the reaction example for obtaining the metallocene complex represented by general formula (I) is shown.

[Wherein X ″ represents a halide. ]

［式中、Ｘ’’はハライドを示す。］ The metallocene complex represented by the general formula (II) includes, for example, a lanthanide trishalide, scandium trishalide, or yttrium trishalide in a solvent, an indenyl salt (for example, potassium salt or lithium salt), and a silyl salt (for example, , Potassium salt or lithium salt). In addition, since reaction temperature should just be about room temperature, it can manufacture on mild conditions. The reaction time is arbitrary, but it is about several hours to several tens of hours. The reaction solvent is not particularly limited, but is preferably a solvent that dissolves the raw material and the product. For example, toluene may be used. Below, the example of reaction for obtaining the metallocene complex represented by general formula (II) is shown.

[Wherein X ″ represents a halide. ]

The half metallocene cation complex represented by the general formula (III) can be obtained, for example, by the following reaction.

Here, in the compound represented by the general formula (IV), M represents a lanthanoid element, scandium or yttrium, and Cp ^{R ′} independently represents unsubstituted or substituted cyclopentadienyl, indenyl or fluorenyl. , X represents a hydrogen atom, a halogen atom, an alkoxy group, a thiolate group, an amino group, a silyl group, or a monovalent hydrocarbon group having 1 to 20 carbon atoms, L represents a neutral Lewis base, w represents An integer from 0 to 3 is shown. In the ionic compound represented by the general formula [A] ⁺ [B] ⁻ , [A] ⁺ represents a cation, and [B] ⁻ represents a non-coordinating anion.

Examples of the cation represented by [A] ⁺ include a carbonium cation, an oxonium cation, an amine cation, a phosphonium cation, a cycloheptatrienyl cation, and a ferrocenium cation having a transition metal. Examples of the carbonium cation include trisubstituted carbonium cations such as a triphenylcarbonium cation and a tri (substituted phenyl) carbonium cation. As the tri (substituted phenyl) carbonyl cation, specifically, tri (methylphenyl) ) Carbonium cation and the like. Examples of amine cations include trialkylammonium cations such as trimethylammonium cation, triethylammonium cation, tripropylammonium cation, and tributylammonium cation; N, N-dimethylanilinium cation, N, N-diethylanilinium cation, N, N— N, N-dialkylanilinium cations such as 2,4,6-pentamethylanilinium cation; dialkylammonium cations such as diisopropylammonium cation and dicyclohexylammonium cation. Examples of the phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tri (methylphenyl) phosphonium cation, and tri (dimethylphenyl) phosphonium cation. Among these cations, N, N-dialkylanilinium cation or carbonium cation is preferable, and N, N-dialkylanilinium cation is particularly preferable.

The ionic compound represented by the general formula [A] ⁺ [B] ⁻ used for the above reaction is a compound selected and combined from the above non-coordinating anions and cations, and is an N, N-dimethylaniline. Preference is given to nium tetrakis (pentafluorophenyl) borate, triphenylcarbonium tetrakis (pentafluorophenyl) borate and the like. The ionic compound represented by the general formula [A] ⁺ [B] ⁻ is preferably added in an amount of 0.1 to 10 times mol, more preferably about 1 time mol based on the metallocene complex. When the half metallocene cation complex represented by the general formula (III) is used for the polymerization reaction, the half metallocene cation complex represented by the general formula (III) may be provided as it is in the polymerization reaction system, or the compound represented by the general formula (IV) and the general formula used in the reaction [a] ⁺ [B] ^- provides an ionic compound represented separately into the polymerization reaction system, the general formula in the reaction system (III You may form the half metallocene cation complex represented by this. Further, by using the metallocene complex represented by the general formula (I) or (II) in combination with the ionic compound represented by the general formula [A] ⁺ [B] ⁻ , the general formula in the reaction system is used. A half metallocene cation complex represented by (III) can also be formed.

The structures of the metallocene complexes represented by the general formulas (I) and (II) and the half metallocene cation complex represented by the general formula (III) are preferably determined by X-ray structural analysis.

Further, as the other component (A-1), the following general formula (V):
R _a MX _b QY _b (V)
[In the formula, each R independently represents unsubstituted or substituted indenyl, the R is coordinated to M, M represents a lanthanoid element, scandium or yttrium, and each X independently represents carbon. 1 represents a monovalent hydrocarbon group of 1 to 20, X is μ-coordinated to M and Q, Q represents a group 13 element of the periodic table, and Y represents each independently a carbon number 1 to 20 monovalent hydrocarbon groups or hydrogen atoms, wherein Y is coordinated to Q, and a and b are 2, for example, a metallocene composite catalyst.

［式中、Ｍ¹は、ランタノイド元素、スカンジウム又はイットリウムを示し、Ｃｐ^Rは、それぞれ独立して無置換もしくは置換インデニルを示し、Ｒ^A及びＲ^Bは、それぞれ独立して炭素数１～２０の炭化水素基を示し、該Ｒ^A及びＲ^Bは、Ｍ¹及びＡｌにμ配位しており、Ｒ^C及びＲ^Dは、それぞれ独立して炭素数１～２０の炭化水素基又は水素原子を示す］で表されるメタロセン系複合触媒が挙げられる。
　上記メタロセン系複合触媒を用いることで、多元共重合体を効率良く製造することができる。また、上記メタロセン系複合触媒、例えば予めアルミニウム触媒と複合させてなる触媒を用いることで、多元共重合体合成時に使用されるアルキルアルミニウムの量を低減したり、無くしたりすることが可能となる。なお、上記メタロセン系複合触媒を用いない従来の触媒系を用いると、多元共重合体合成時に大量のアルキルアルミニウムを用いる必要がある。例えば、上記メタロセン系複合触媒を用いない従来の触媒系では、金属触媒に対して１０モル当量以上のアルキルアルミニウムを用いる必要があるところ、上記メタロセン系複合触媒であれば、５モル当量程度のアルキルアルミニウムを加えることで、優れた触媒作用が発揮される。 In a preferred example of the metallocene composite catalyst, the following general formula (VI):

[ ^Wherein , M ¹ represents a lanthanoid element, scandium or yttrium, Cp ^R independently represents an unsubstituted or substituted indenyl group, and R ^A and R ^B each independently represents one having 1 to 20 carbon atoms. R ^A and R ^B are μ-coordinated to M ¹ and Al, and R ^C and R ^D each independently represent a hydrocarbon group having 1 to 20 carbon atoms or a hydrogen atom. A metallocene composite catalyst represented by
By using the metallocene composite catalyst, a multi-component copolymer can be produced efficiently. In addition, by using the metallocene composite catalyst, for example, a catalyst previously combined with an aluminum catalyst, it is possible to reduce or eliminate the amount of alkylaluminum used during the synthesis of the multi-component copolymer. If a conventional catalyst system that does not use the metallocene composite catalyst is used, it is necessary to use a large amount of alkylaluminum during the synthesis of the multi-component copolymer. For example, in a conventional catalyst system that does not use the metallocene composite catalyst, it is necessary to use 10 mole equivalents or more of alkylaluminum with respect to the metal catalyst. By adding aluminum, an excellent catalytic action is exhibited.

In the metallocene composite catalyst, the metal M in the general formula (V) is a lanthanoid element, scandium or yttrium. The lanthanoid elements include 15 elements having atomic numbers of 57 to 71, and any of these may be used. Preferred examples of the metal M include samarium Sm, neodymium Nd, praseodymium Pr, gadolinium Gd, cerium Ce, holmium Ho, scandium Sc, and yttrium Y.

In the general formula (V), each R is independently an unsubstituted indenyl or a substituted indenyl, and the R is coordinated to the metal M. Specific examples of substituted indenyl include, for example, 1,2,3-trimethylindenyl group, heptamethylindenyl group, 1,2,4,5,6,7-hexamethylindenyl group, and the like. .

In the above general formula (V), Q represents a group 13 element in the periodic table, and specific examples include boron, aluminum, gallium, indium, thallium and the like.

In the above general formula (V), each X independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and X is μ-coordinated to M and Q. Here, the monovalent hydrocarbon group having 1 to 20 carbon atoms includes methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, tridecyl group. Tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, stearyl group and the like. Note that the μ coordination is a coordination mode having a crosslinked structure.

In the general formula (V), each Y independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms or a hydrogen atom, and the Y is coordinated to Q. Here, the monovalent hydrocarbon group having 1 to 20 carbon atoms includes methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, tridecyl group. Tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, stearyl group and the like.

In the above general formula (VI), the metal M ¹ is a lanthanoid element, scandium or yttrium. The lanthanoid elements include 15 elements having atomic numbers of 57 to 71, and any of these may be used. Preferable examples of the metal M ¹ include samarium Sm, neodymium Nd, praseodymium Pr, gadolinium Gd, cerium Ce, holmium Ho, scandium Sc, and yttrium Y.

In the above general formula (VI), Cp ^R is unsubstituted indenyl or substituted indenyl. Cp ^R having an indenyl ring as a basic skeleton can be represented by C ₉ H _7-X R _X or C ₉ H _11-X R _X. Here, X is an integer of 0 to 7 or 0 to 11. In addition, each R is preferably independently a hydrocarbyl group or a metalloid group. The hydrocarbyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 8 carbon atoms. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of the metalloid of the metalloid group include germyl Ge, stannyl Sn, silyl Si, and the metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group of the metalloid group is It is the same. Specific examples of the metalloid group include a trimethylsilyl group.
Specific examples of the substituted indenyl include 2-phenylindenyl, 2-methylindenyl and the like. Note that the two Cp ^R 's in formula (VI) may be the same as or different from each other.

In the general formula (VI), R ^A and R ^B each independently represent a monovalent hydrocarbon group having 1 to 20 carbon atoms, and R ^A and R ^B are μ-coordinated to M ¹ and Al. is doing. Here, the monovalent hydrocarbon group having 1 to 20 carbon atoms includes a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, and a tridecyl group. Tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, stearyl group and the like. The μ coordination is a coordination mode having a crosslinked structure.

In the general formula (VI), R ^C and R ^D are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms or a hydrogen atom. Here, the monovalent hydrocarbon group having 1 to 20 carbon atoms includes a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, and a tridecyl group. Tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, stearyl group and the like.

［式中、Ｍ²は、ランタノイド元素、スカンジウム又はイットリウムを示し、Ｃｐ^Rは、それぞれ独立して無置換もしくは置換インデニルを示し、Ｒ^E～Ｒ^Jは、それぞれ独立して炭素数１～３のアルキル基又は水素原子を示し、Ｌは、中性ルイス塩基を示し、ｗは、０～３の整数を示す］で表されるメタロセン錯体を、ＡｌＲ^KＲ^LＲ^Mで表される有機アルミニウム化合物と反応させることで得られる。なお、反応温度は、室温程度にすればよいので、温和な条件で製造することができる。また、反応時間は、任意であるが、数時間～数十時間程度である。反応溶媒は、特に限定されないが、原料及び生成物を溶解する溶媒であることが好ましく、例えば、トルエンやヘキサンを用いればよい。なお、上記メタロセン系複合触媒の構造は、¹Ｈ－ＮＭＲやＸ線構造解析により決定することが好ましい。 The metallocene composite catalyst is, for example, in a solvent in the following general formula (VII):

[ ^Wherein M ² represents a lanthanoid element, scandium or yttrium, Cp ^R each independently represents an unsubstituted or substituted indenyl group, and R ^E to R ^J each independently represents one having 1 to 3 carbon atoms. an alkyl group or a hydrogen atom, L is a neutral Lewis base, w is, the metallocene complex represented by an integer of 0 to 3], the organoaluminum compound represented by AlR ^K R ^L R ^M It is obtained by reacting with. In addition, since reaction temperature should just be about room temperature, it can manufacture on mild conditions. The reaction time is arbitrary, but it is about several hours to several tens of hours. The reaction solvent is not particularly limited, but is preferably a solvent that dissolves the raw material and the product. For example, toluene or hexane may be used. The structure of the metallocene composite catalyst is preferably determined by ¹ H-NMR or X-ray structural analysis.

In the metallocene complex represented by the general formula (VII), Cp ^R is unsubstituted indenyl or substituted indenyl, and has the same meaning as Cp ^R in the general formula (VI). In the above formula (VII), the metal M ² is a lanthanoid element, scandium or yttrium, and has the same meaning as the metal M ¹ in the above formula (VI).

The metallocene complex represented by the general formula (VII) includes a silylamide ligand [—N (SiR ₃ ) ₂ ]. The R groups (R ^E to R ^J groups) contained in the silylamide ligand are each independently an alkyl group having 1 to 3 carbon atoms or a hydrogen atom. Further, at least one of R ^E to R ^J is preferably a hydrogen atom. By making at least one of R ^E to R ^J a hydrogen atom, the catalyst can be easily synthesized. Furthermore, the alkyl group is preferably a methyl group.

The metallocene complex represented by the general formula (VII) further contains 0 to 3, preferably 0 to 1, neutral Lewis base L. Here, examples of the neutral Lewis base L include tetrahydrofuran, diethyl ether, dimethylaniline, trimethylphosphine, lithium chloride, neutral olefins, neutral diolefins, and the like. Here, when the complex includes a plurality of neutral Lewis bases L, the neutral Lewis bases L may be the same or different.

In addition, the metallocene complex represented by the general formula (VII) may exist as a monomer, or may exist as a dimer or a higher multimer.

On the other hand, the organoaluminum compound used for producing the metallocene composite catalyst is represented by AlR ^K R ^L R ^M , where R ^K and R ^L are each independently a monovalent carbon atom having 1 to 20 carbon atoms. In the hydrogen group or hydrogen atom, R ^M is a monovalent hydrocarbon group having 1 to 20 carbon atoms, provided that R ^M may be the same as or different from R ^K or R ^L described above. Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group , Pentadecyl group, hexadecyl group, heptadecyl group, stearyl group and the like.

Specific examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-t-butylaluminum, tripentylaluminum, tri Hexyl aluminum, tricyclohexyl aluminum, trioctyl aluminum; diethyl aluminum hydride, di-n-propyl aluminum hydride, di-n-butyl aluminum hydride, diisobutyl aluminum hydride, dihexyl aluminum hydride, diisohexyl aluminum hydride, dioctyl aluminum hydride, di Isooctyl aluminum hydride; ethyl Rumi bromide dihydride, n- propyl aluminum dihydride, include isobutyl aluminum dihydride and the like, among these, triethylaluminum, triisobutylaluminum, diethylaluminum hydride, diisobutylaluminum hydride are preferred. Moreover, these organoaluminum compounds can be used individually by 1 type, or 2 or more types can be mixed and used for them. The amount of the organoaluminum compound used for the production of the metallocene composite catalyst is preferably 1 to 50 times mol, more preferably about 10 times mol relative to the metallocene complex.

The component (A-2) is a rare earth element compound or a reaction product of the rare earth element compound and a Lewis base, and does not have a bond between the rare earth element and carbon. When the rare earth element compound and the reactant do not have a rare earth element-carbon bond, the compound is stable and easy to handle. Here, the rare earth element compound is a rare earth element (M), that is, a lanthanoid element composed of elements having atomic numbers 57 to 71 in the periodic table, or a compound containing scandium or yttrium.
Specific examples of the lanthanoid element include lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. The component (A-2) may be used alone or in combination of two or more.

The rare earth element compound is preferably a salt or complex compound of a divalent or trivalent rare earth metal, and one or more coordinations selected from a hydrogen atom, a halogen atom and an organic compound residue. More preferably, the rare earth element compound contains a child. Furthermore, the reaction product of the rare earth element compound or the rare earth element compound and a Lewis base is represented by the following general formula (VIII) or (IX):
M ¹¹ X ¹¹ ₂・ L ¹¹ _w ... (VIII)
M ¹¹ X ¹¹ ₃・ L ¹¹ _w ... (IX)
[In each formula, M ¹¹ represents a lanthanoid element, scandium or yttrium, and X ¹¹ independently represents a hydrogen atom, a halogen atom, an alkoxy group, a thiolate group, an amino group, a silyl group, an aldehyde residue, Represents a ketone residue, a carboxylic acid residue, a thiocarboxylic acid residue or a phosphorus compound residue, L ¹¹ represents a Lewis base, and w represents 0 to 3.

Examples of the group (ligand) bonded to the rare earth element of the rare earth element compound include a hydrogen atom, a halogen atom, an alkoxy group (a group in which an alcohol hydroxyl group is removed, and forms a metal alkoxide), a thiolate group ( A group obtained by removing hydrogen from a thiol group of a thiol compound and forming a metal thiolate), an amino group (a group obtained by removing one hydrogen atom bonded to a nitrogen atom of ammonia, a primary amine, or a secondary amine) And forms a metal amide), silyl group, aldehyde residue, ketone residue, carboxylic acid residue, thiocarboxylic acid residue, and phosphorus compound residue.
Specific examples of the group (ligand) include a hydrogen atom; an aliphatic alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, and a tert-butoxy group; Phenoxy group, 2,6-di-tert-butylphenoxy group, 2,6-diisopropylphenoxy group, 2,6-dineopentylphenoxy group, 2-tert-butyl-6-isopropylphenoxy group, 2-tert-butyl -6-neopentylphenoxy group, 2-isopropyl-6-neopentylphenoxy group; thiomethoxy group, thioethoxy group, thiopropoxy group, thio n-butoxy group, thioisobutoxy group, thiosec-butoxy group, thiotert-butoxy Aliphatic thiolate groups such as thiophene groups; thiophenoxy groups, 2,6-di-tert-butyl Ofenoxy group, 2,6-diisopropylthiophenoxy group, 2,6-dineopentylthiophenoxy group, 2-tert-butyl-6-isopropylthiophenoxy group, 2-tert-butyl-6-thioneopentylphenoxy group, Arylthiolate groups such as 2-isopropyl-6-thioneopentylphenoxy group and 2,4,6-triisopropylthiophenoxy group; aliphatic amino groups such as dimethylamino group, diethylamino group and diisopropylamino group; phenylamino group; 2,6-di-tert-butylphenylamino group, 2,6-diisopropylphenylamino group, 2,6-dineopentylphenylamino group, 2-tert-butyl-6-isopropylphenylamino group, 2-tert- Butyl-6-neopentylphenylamino group, -Arylamino groups such as isopropyl-6-neopentylphenylamino group, 2,4,6-tri-tert-butylphenylamino group; bistrialkylsilylamino groups such as bistrimethylsilylamino group; trimethylsilyl group, tris (trimethylsilyl) Silyl groups such as silyl group, bis (trimethylsilyl) methylsilyl group, trimethylsilyl (dimethyl) silyl group, triisopropylsilyl (bistrimethylsilyl) silyl group; halogen atoms such as fluorine atom, chlorine atom, bromine atom, iodine atom, etc. .
As the group (ligand), a residue of an aldehyde such as salicylaldehyde, 2-hydroxy-1-naphthaldehyde, 2-hydroxy-3-naphthaldehyde; 2′-hydroxyacetophenone, 2′-hydroxybutyrophenone Residues of hydroxyphenone such as 2′-hydroxypropiophenone; Ketone residues (particularly diketone residues) such as acetylacetone, benzoylacetone, propionylacetone, isobutylacetone, valerylacetone, ethylacetylacetone; Herbic acid, caprylic acid, octanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, cyclopentanecarboxylic acid, naphthenic acid, ethylhexanoic acid, pivalic acid, versatic acid [shell chemistry ( Quotient made by Name, synthetic acid composed of a mixture of isomers of C10 monocarboxylic acid], residues of carboxylic acids such as phenylacetic acid, benzoic acid, 2-naphthoic acid, maleic acid, succinic acid; hexanethioic acid, 2,2- Residues of thiocarboxylic acids such as dimethylbutanethioic acid, decanethioic acid, thiobenzoic acid; dibutyl phosphate, dipentyl phosphate, dihexyl phosphate, diheptyl phosphate, dioctyl phosphate, bis (2-ethylhexyl) phosphate, phosphoric acid Bis (1-methylheptyl), dilauryl phosphate, dioleyl phosphate, diphenyl phosphate, bis (p-nonylphenyl) phosphate, bis (polyethylene glycol-p-nonylphenyl) phosphate, (butyl) phosphate (2 -Ethylhexyl), phosphoric acid (1-methylheptyl) (2-ethylhexyl), phosphoric acid (2-ethylhexyl) Residues of phosphate esters such as (p-nonylphenyl); monobutyl 2-ethylhexylphosphonate, mono-2-ethylhexyl 2-ethylhexylphosphonate, mono-2-ethylhexyl phenylphosphonate, mono-p-ethylhexylphosphonate Residues of phosphonates such as nonylphenyl, mono-2-ethylhexyl phosphonate, mono-1-methylheptyl phosphonate, mono-p-nonylphenyl phosphonate; dibutylphosphinic acid, bis (2-ethylhexyl) phosphinic acid Bis (1-methylheptyl) phosphinic acid, dilaurylphosphinic acid, dioleylphosphinic acid, diphenylphosphinic acid, bis (p-nonylphenyl) phosphinic acid, butyl (2-ethylhexyl) phosphinic acid, (2-ethylhexyl) ( 1-methyl Heptyl) phosphinic acid, (2-ethylhexyl) (p-nonylphenyl) phosphinic acid, butylphosphinic acid, 2-ethylhexylphosphinic acid, 1-methylheptylphosphinic acid, oleylphosphinic acid, laurylphosphinic acid, phenylphosphinic acid, p- Mention may also be made of phosphinic acid residues such as nonylphenylphosphinic acid.
In addition, these groups (ligand) may be used individually by 1 type, and may be used in combination of 2 or more type.

Examples of the Lewis base that reacts with the rare earth element compound include tetrahydrofuran, diethyl ether, dimethylaniline, trimethylphosphine, lithium chloride, neutral olefins, neutral diolefins, and the like. Here, when the rare earth element compound reacts with a plurality of Lewis bases (when w is 2 or 3 in the general formulas (VIII) and (IX)), the Lewis base L ¹¹ may be the same. May be different.

Preferably, as the rare earth element compound, the following general formula (X):
M- (AQ ¹ ) (AQ ² ) (AQ ³ ) (X)
[Wherein M is a scandium, yttrium or lanthanoid element; AQ ¹ , AQ ² and AQ ³ are functional groups which may be the same or different; A is nitrogen, oxygen or sulfur; Yes; provided that it has at least one MA bond]. Here, the lanthanoid element is specifically lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. The compound is a component that can improve the catalytic activity in the reaction system, shorten the reaction time, and increase the reaction temperature.

As M in the general formula (X), gadolinium is particularly preferable from the viewpoint of enhancing catalyst activity and reaction controllability.

When A in the general formula (X) is nitrogen, examples of the functional group represented by AQ ¹ , AQ ² and AQ ³ (that is, NQ ¹ , NQ ² and NQ ³ ) include an amino group. And in this case, it has three MN bonds.

Examples of the amino group include aliphatic amino groups such as dimethylamino group, diethylamino group, and diisopropylamino group; phenylamino group, 2,6-di-tert-butylphenylamino group, 2,6-diisopropylphenylamino group, 2,6-dineopentylphenylamino group, 2-tert-butyl-6-isopropylphenylamino group, 2-tert-butyl-6-neopentylphenylamino group, 2-isopropyl-6-neopentylphenylamino group, Examples include arylamino groups such as 2,4,6-tri-tert-butylphenylamino group; bistrialkylsilylamino groups such as bistrimethylsilylamino group, etc., and particularly solubility in aliphatic hydrocarbons and aromatic hydrocarbons. From this viewpoint, a bistrimethylsilylamino group is preferable. The said amino group may be used individually by 1 type, and may be used in combination of 2 or more type.

According to the above configuration, the component (A-2) can be a compound having three MN bonds, and each bond is chemically equivalent, and the structure of the compound is stable. Become.
Moreover, if it is set as the said structure, the catalyst activity in a reaction system can be improved further. Therefore, the reaction time can be further shortened and the reaction temperature can be further increased.

When A in the general formula (X) is oxygen, the rare earth element-containing compound represented by the general formula (X) (that is, M- (OQ ¹ ) (OQ ² ) (OQ ³ )) is particularly limited. For example, the following general formula (XI):
(RO) ₃ M (XI)
Or a rare earth alcoholate represented by the following general formula (XII):
(R-CO ₂ ) ₃ M (XII)
And rare earth carboxylates represented by
Here, in the general formulas (XI) and (XII), R may be the same or different and is an alkyl group having 1 to 10 carbon atoms.

When A in the general formula (X) is sulfur, the rare earth element-containing compound represented by the general formula (X) (that is, M- (SQ ¹ ) (SQ ² ) (SQ ³ )) is particularly limited. For example, the following general formula (XIII):
(RS) ₃ M (XIII)
Or a rare earth alkylthiolate represented by the following general formula (XIV):
(R-CS ₂ ) ₃ M (XIV)
The compound etc. which are represented by these are mentioned.
Here, in the general formulas (XIII) and (XIV), R may be the same or different and is an alkyl group having 1 to 10 carbon atoms.

The organometallic compound (component (B)) is represented by the following general formula (XV):
YR ¹ _a R ² _b R ³ _c (XV)
[Wherein Y is a metal selected from Group 1, Group 2, Group 12 and Group 13 of the Periodic Table, and R ¹ and R ² are each a hydrocarbon group having 1 to 10 carbon atoms or R ³ is a hydrogen atom and is a hydrocarbon group having 1 to 10 carbon atoms, provided that R ¹ , R ² and R ³ may be the same or different from each other, and Y is group 1 of the periodic table A is 1 and b and c are 0, and when Y is a metal selected from Groups 2 and 12 of the Periodic Table, a and b are selected. Is 1 and c is 0, and when Y is a metal selected from Group 13 of the Periodic Table, a, b and c are 1.].

In the general formula (XV), the hydrocarbon group having 1 to 10 carbon atoms represented by R ¹ , R ² and R ³ is specifically a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n- Linear or branched aliphatic hydrocarbon groups such as butyl, isobutyl, sec-butyl, tert-butyl, neopentyl, hexyl and octyl; aromatics such as phenyl, tolyl and naphthyl A hydrocarbon group; an aralkyl group such as a benzyl group, and the like. Among these, a methyl group, an ethyl group, an isobutyl group, and the like are preferable.

As the component (B), the following general formula (XVI):
AlR ¹ R ² R ³ ... (XVI)
[Wherein R ¹ and R ² are hydrocarbon groups or hydrogen atoms having 1 to 10 carbon atoms, and R ³ is a hydrocarbon group having 1 to 10 carbon atoms, provided that R ¹ , R ² and R ³ May be the same or different from each other]. The organoaluminum compound corresponds to a compound in which Y is Al and a, b, and c are 1 in the general formula (XV).

Examples of the organoaluminum compound of the general formula (XVI) include trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-t-butylaluminum, and tripentyl. Aluminum, trihexyl aluminum, tricyclohexyl aluminum, trioctyl aluminum; diethyl aluminum hydride, di-n-propyl aluminum hydride, di-n-butyl aluminum hydride, diisobutyl aluminum hydride, dihexyl aluminum hydride, diisohexyl aluminum hydride, dioctyl aluminum Hydride, diisooctyl aluminum hydride ; Ethylaluminum dihydride, n- propyl aluminum dihydride, isobutyl aluminum dihydride and the like. Among these, triethylaluminum, triisobutylaluminum, diethylaluminum hydride, diisobutylaluminum hydride are preferred.

The component (B) can be used singly or in combination of two or more. In addition, when the component (B) is used together with the component (A), the amount is preferably 1 to 50 times mol, more preferably about 10 times mol to the component (A). preferable.

The aluminoxane (component (C)) is a compound obtained by bringing an organoaluminum compound and a condensing agent into contact with each other. By using the component (C), the catalytic activity in the polymerization reaction system can be further improved, so that the desired copolymer can be easily obtained. Further, the reaction time can be further shortened and the reaction temperature can be further increased.

Here, examples of the organoaluminum compound include trialkylaluminum such as trimethylaluminum, triethylaluminum, and triisobutylaluminum, and a mixture thereof. In particular, a mixture of trimethylaluminum and trimethylaluminum and tributylaluminum is preferable. .
On the other hand, examples of the condensing agent include water.

Examples of the component (C) include the following formula (XVII):
-(Al (R ⁷ ) O) _n- (XVII)
Wherein, R ⁷ is a hydrocarbon group having 1 to 10 carbon atoms, wherein a portion of the hydrocarbon group may be substituted by halogen and / or alkoxy group; R ⁷ is between the repeating units And may be the same or different; n is 5 or more].
The molecular structure of the aluminoxane may be linear or cyclic.
N in the formula (XVII) is preferably 10 or more.
Moreover, regarding R ⁷ in the above formula (XVII), examples of the hydrocarbon group include a methyl group, an ethyl group, a propyl group, an isobutyl group, and the like, and a methyl group is particularly preferable. 1 type may be sufficient as this hydrocarbon group and it may combine 2 or more types. Regarding R ⁷ in formula (XVII), the hydrocarbon group is preferably a combination of a methyl group and an isobutyl group.
The aluminoxane preferably has high solubility in aliphatic hydrocarbons, and preferably has low solubility in aromatic hydrocarbons. For example, aluminoxane marketed as a hexane solution is preferable.
Here, examples of the aliphatic hydrocarbon include hexane and cyclohexane.

The component (C) is particularly represented by the following formula (XVIII):
-(Al (CH ₃ ) _x (iC ₄ H ₉ ) _y O) _m- (XVIII)
[Wherein, x + y is 1; m is 5 or more]. An example of TMAO is a product name “TMAO-341” manufactured by Tosoh Fine Chemical Co., Ltd.

In addition, the component (C) is particularly represented by the following formula (XIX):
-(Al (CH ₃ ) _0.7 (iC ₄ H ₉ ) _0.3 O) _k- (XIX)
[Wherein k is 5 or more] may be used as a modified aluminoxane (hereinafter also referred to as “MMAO”). An example of MMAO is a product name “MMAO-3A” manufactured by Tosoh Fine Chemical Co., Ltd.

Furthermore, the component (C) is particularly represented by the following formula (XX):
-[(CH ₃ ) AlO] _i- (XX)
[Wherein i is 5 or more] may be a modified aluminoxane (hereinafter also referred to as “PMAO”). An example of PMAO is “PMAO-211” manufactured by Tosoh Fine Chemical Co., Ltd.

The component (C) is preferably MMAO or TMAO among the MMAO, TMAO, and PMAO from the viewpoint of improving the effect of improving the catalyst activity, and particularly from the viewpoint of further enhancing the effect of improving the catalyst activity. More preferably, it is TMAO.

The component (C) can be used singly or in combination of two or more. Further, from the viewpoint of improving the catalytic activity, the component (C), when used together with the component (A), is 10 mol of aluminum in the component (C) with respect to 1 mol of the rare earth element in the component (A). It is preferably used so as to be above, more preferably used so as to be 100 mol or more, and preferably used so as to be 1000 mol or less, and used so as to be 800 mol or less. More preferably.

The ionic compound (component (D)) comprises a non-coordinating anion and a cation. When the component (D) is used together with the component (A) described above, examples of the component (D) include ionic compounds that can react with the component (A) to form a cationic transition metal compound.

Here, as the non-coordinating anion, tetravalent boron anions such as tetraphenyl borate, tetrakis (monofluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluoro) Phenyl) borate, tetrakis (pentafluorophenyl) borate, tetrakis (tetrafluoromethylphenyl) borate, tetra (tolyl) borate, tetra (xylyl) borate, (triphenyl, pentafluorophenyl) borate, [tris (pentafluorophenyl) , Phenyl] borate, tridecahydride-7,8-dicarbaundecaborate and the like. Among these, tetrakis (pentafluorophenyl) borate is preferable.

On the other hand, examples of the cation include a carbonium cation, an oxonium cation, an amine cation, a phosphonium cation, a cycloheptatrienyl cation, and a ferrocenium cation having a transition metal. Specific examples of carbonium cations include trisubstituted carbonium cations such as triphenylcarbonium cation (also referred to as “trityl cation”), tri (substituted phenyl) carbonium cation, and the like, and tri (substituted phenyl) carbonyl cation. More specifically, tri (methylphenyl) carbonium cation, tri (dimethylphenyl) carbonium cation and the like can be mentioned. Examples of the amine cation include an ammonium cation. Specific examples of the ammonium cation include trimethylammonium cation, triethylammonium cation, tripropylammonium cation, and tributylammonium cation (for example, tri (n-butyl) ammonium cation). N, N-dimethylanilinium cation, N, N-diethylanilinium cation, N, N-2,4,6-pentamethylanilinium cation and the like N, N-dialkylanilinium cation; diisopropyl Examples thereof include dialkylammonium cations such as ammonium cation and dicyclohexylammonium cation. Specific examples of the phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tri (methylphenyl) phosphonium cation, and tri (dimethylphenyl) phosphonium cation. Among these cations, N, N-dialkylanilinium cation or carbonium cation is preferable, and N, N-dialkylanilinium cation is particularly preferable.

Therefore, the ionic compound (component (D)) is preferably a compound selected and combined from the above-mentioned non-coordinating anions and cations, specifically, N, N-dimethylanilinium tetrakis (pentafluoro). Phenyl) borate, triphenylcarbonium tetrakis (pentafluorophenyl) borate and the like are preferable.

The component (D) can be used singly or in combination of two or more. In addition, when the component (D) is used together with the component (A) described above, the amount used is preferably 0.1 to 10 times mol and about 1 times mol to the component (A). Is more preferable.

Examples of the halogen compound (component (E)) include a halogen-containing compound which is a Lewis acid (hereinafter also referred to as “(E-1) component”), a complex compound of a metal halide and a Lewis base (hereinafter referred to as “( E-2) component ”), organic compounds containing an active halogen (hereinafter also referred to as“ (E-3) component ”), and the like. For example, when the component (E) is used together with the component (A), the component (A) reacts with the component (A) to form a cationic transition metal compound, a halogenated transition metal compound, or a compound whose transition metal center is deficient in charge. Can be generated.

As the component (E-1), for example, an element of Group 3, Group 4, Group 5, Group 6, Group 8, Group 13, Group 14 or Group 15 in the Periodic Table A halogen compound containing can be used. Preferably, aluminum halide or organometallic halide is used. Moreover, as a halogen element, chlorine or bromine is preferable.
Specific examples of the halogen-containing compound that is the Lewis acid include methylaluminum dibromide, methylaluminum dichloride, ethylaluminum dibromide, ethylaluminum dichloride, butylaluminum dibromide, butylaluminum dichloride, dimethylaluminum bromide, dimethylaluminum chloride, Diethylaluminum bromide, diethylaluminum chloride, dibutylaluminum bromide, dibutylaluminum chloride, methylaluminum sesquibromide, methylaluminum sesquichloride, ethylaluminum sesquichloride, ethylaluminum sesquichloride, dibutyltin dichloride, aluminum tribromide, tri (pentafluorophenyl) Aluminum, tri (pentafluorophenyl) borate, antimony trichloride, antimony pentachloride, phosphorus trichloride, phosphorus pentachloride, tin tetrachloride, titanium tetrachloride, tungsten hexachloride, etc. Among these, diethylaluminum chloride, Particularly preferred are ethylaluminum sesquichloride, ethylaluminum dichloride, diethylaluminum bromide, ethylaluminum sesquibromide, and ethylaluminum dibromide.
The component (E-1) may be used alone or in combination of two or more.

Examples of the metal halide constituting the component (E-2) include beryllium chloride, beryllium bromide, beryllium iodide, magnesium chloride, magnesium bromide, magnesium iodide, calcium chloride, calcium bromide, calcium iodide, and chloride. Barium, barium bromide, barium iodide, zinc chloride, zinc bromide, zinc iodide, cadmium chloride, cadmium bromide, cadmium iodide, mercury chloride, mercury bromide, mercury iodide, manganese chloride, manganese bromide, Manganese iodide, rhenium chloride, rhenium bromide, rhenium iodide, copper chloride, copper iodide, silver chloride, silver bromide, silver iodide, gold chloride, gold iodide, gold bromide, etc., and these Of these, magnesium chloride, calcium chloride, barium chloride, manganese chloride, zinc chloride, and copper chloride are preferable. Magnesium chloride, chloride Ngan, zinc chloride, copper chloride being particularly preferred.
As the Lewis base constituting the component (E-2), phosphorus compounds, carbonyl compounds, nitrogen compounds, ether compounds, alcohols and the like are preferable. Specifically, tributyl phosphate, tri-2-ethylhexyl phosphate, triphenyl phosphate, tricresyl phosphate, triethylphosphine, tributylphosphine, triphenylphosphine, diethylphosphinoethane, diphenylphosphinoethane, acetylacetone, benzoylacetone , Propionitrile acetone, valeryl acetone, ethyl acetylacetone, methyl acetoacetate, ethyl acetoacetate, phenyl acetoacetate, dimethyl malonate, diethyl malonate, diphenyl malonate, acetic acid, octanoic acid, 2-ethyl-hexanoic acid, olein Acid, stearic acid, benzoic acid, naphthenic acid, versatic acid, triethylamine, N, N-dimethylacetamide, tetrahydrofuran, diphenyl ether, 2-ethyl-hexyl alcohol Examples include oleyl alcohol, stearyl alcohol, phenol, benzyl alcohol, 1-decanol, and lauryl alcohol. Among these, tri-2-ethylhexyl phosphate, tricresyl phosphate, acetylacetone, 2-ethylhexanoic acid, versatic acid, 2 -Ethylhexyl alcohol, 1-decanol, lauryl alcohol are preferred.
The Lewis base is reacted at a ratio of 0.01 to 30 mol, preferably 0.5 to 10 mol, per 1 mol of the metal halide. When the reaction product with the Lewis base is used, the metal remaining in the polymer can be reduced.
The component (E-2) may be used alone or in combination of two or more.

Examples of the component (E-3) include benzyl chloride.

The component (E) can be used singly or as a mixture of two or more. In addition, when the component (E) is used together with the component (A), it is preferably 0 to 5 times mol, more preferably 1 to 5 times mol of the component (A). preferable.

The cyclopentadiene skeleton-containing compound (component (F)) has a group selected from a cyclopentadienyl group, an indenyl group, and a fluorenyl group, and the cyclopentadiene skeleton-containing compound (F) is substituted or unsubstituted. It is at least one compound selected from the group consisting of cyclopentadiene, substituted or unsubstituted indene, substituted or unsubstituted fluorene. The said (F) component may be used individually by 1 type, and may be used in combination of 2 or more type.

Examples of the substituted or unsubstituted cyclopentadiene include cyclopentadiene, pentamethylcyclopentadiene, tetramethylcyclopentadiene, isopropylcyclopentadiene, trimethylsilyl-tetramethylcyclopentadiene, (1-benzyldimethylsilyl) cyclopenta [l] phenanthrene, and the like. Is mentioned.

Examples of the substituted or unsubstituted indene include indene, 2-phenyl-1H-indene, 3-benzyl-1H-indene, 3-methyl-2-phenyl-1H-indene, and 3-benzyl-2-phenyl- 1H-indene, 1-benzyl-1H-indene, 1-methyl-3-dimethylbenzylsilyl-indene, 1,3-bis (t-butyldimethylsilyl) -indene, (1-benzyldimethylsilyl-3-cyclopentyl) Indene, (1-benzyl-3-t-butyldimethylsilyl) indene and the like can be mentioned, and 3-benzyl-1H-indene and 1-benzyl-1H-indene are particularly preferable from the viewpoint of reducing the molecular weight distribution.

Examples of the substituted or unsubstituted fluorene include fluorene, trimethylsilylfluorene, isopropylfluorene, and the like.

In particular, the cyclopentadiene skeleton-containing compound (component (F)) is preferably a substituted cyclopentadiene, a substituted indene or a substituted fluorene, and more preferably a substituted indene. Thereby, since the bulk height as a polymerization catalyst increases advantageously, reaction time can be shortened and reaction temperature can be made high. Moreover, since many conjugated electrons are provided, the catalytic activity in the reaction system can be further improved.

Here, examples of the substituent of the substituted cyclopentadiene, substituted indene, and substituted fluorene include a hydrocarbyl group and a metalloid group, and the hydrocarbyl group preferably has 1 to 20 carbon atoms, and more preferably 1 to 10 carbon atoms. It is preferably 1 to 8, and more preferably. Specific examples of the hydrocarbyl group include a methyl group, an ethyl group, a phenyl group, and a benzyl group. On the other hand, examples of metalloid group metalloids include germyl Ge, stannyl Sn, and silyl Si, and the metalloid group preferably has a hydrocarbyl group, and the hydrocarbyl group that the metalloid group has is the same as the above hydrocarbyl group. is there. Specific examples of the metalloid group include a trimethylsilyl group.

The component (F) can be used alone or in combination of two or more. The amount of the component (F) used is preferably more than 0 as the molar ratio to the component (A) when used together with the component (A) from the viewpoint of improving the catalytic activity. More preferably, it is more preferably 1, or more, more preferably 3 or less, further preferably 2.5 or less, and particularly preferably 2.2 or less.

The above-mentioned components (A) to (F) are preferably combined in various ways and used in the polymerization step as a catalyst composition. Suitable catalyst compositions include the following first catalyst composition and second catalyst composition.

The first catalyst composition includes the component (A-1), the component (B), and the component (D), and further includes the component (C) and the component (E) as optional components. It is preferable to include one or more components. In the case where the component (A-1) is a metallocene composite catalyst represented by the general formula (V), the component (B) is also an optional component.

The second catalyst composition includes the component (A-2), the component (B), and the component (D), and further includes the component (C) and the component (E) as optional components. ) Component and at least one of the component (F). In addition, when a 2nd catalyst composition contains (F) component, catalyst activity improves.

The coupling step is a step of performing a reaction (coupling reaction) for modifying at least a part (for example, a terminal) of the polymer chain of the multi-component copolymer obtained in the polymerization step.
In the coupling step, the coupling reaction is preferably performed when the polymerization reaction reaches 100%.
The coupling agent used in the coupling reaction is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a tin-containing compound such as bis (-1-octadecyl maleate) dioctyl tin (IV); Examples include isocyanate compounds such as 4,4′-diphenylmethane diisocyanate; alkoxysilane compounds such as glycidylpropyltrimethoxysilane, and the like. These may be used individually by 1 type and may use 2 or more types together.
Among these, bis (-1-octadecyl maleate) dioctyltin (IV) is preferable from the viewpoint of reaction efficiency and low gel formation.
In addition, the number average molecular weight (Mn) can be increased by performing a coupling reaction.

The washing step is a step of washing the multi-component copolymer obtained in the polymerization step. The medium used for washing is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include methanol, ethanol, isopropanol and the like. When a catalyst derived from a Lewis acid is used as a polymerization catalyst. Can be used by adding an acid (for example, hydrochloric acid, sulfuric acid, nitric acid, etc.) to these solvents. The amount of the acid to be added is preferably 15 mol% or less with respect to the solvent. Above this, the acid remains in the multi-component copolymer, which may adversely affect the reaction during kneading and vulcanization.
By this washing step, the amount of catalyst residue in the multi-component copolymer can be suitably reduced.

In the rubber composition of the present invention, the content of the multi-component copolymer (a1) in the rubber component (a) is preferably in the range of 5 to 100% by mass, and more preferably in the range of 10 to 100% by mass. A range of 15 to 100% by mass is even more preferable. If the content of the multi-component copolymer (a1) in the rubber component (a) is 5% by mass or more, the effect of the multi-component copolymer (a1) is sufficiently exerted, and the wear resistance of the rubber composition is improved. By further improving and applying to a tire, the wear resistance of the tire can be further improved.

There is no restriction | limiting in particular as rubber components other than the said multicomponent copolymer (a1) in the said rubber component (a), According to the objective, it can select suitably, For example, natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), acrylonitrile-butadiene rubber (NBR), chloroprene rubber, ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), polysulfide rubber, silicone rubber, fluorine rubber, urethane rubber Etc. These may be used individually by 1 type, and 2 or more types may be mixed and used for them.

The rubber composition of the present invention contains a foaming agent (b). When the rubber composition contains the foaming agent (b), when the rubber composition is vulcanized to produce a vulcanized rubber, bubbles derived from the foaming agent are formed in the vulcanized rubber. Accordingly, when a tire is produced using the rubber composition containing the foaming agent (b) in the tread, the on-ice performance of the tire can be improved due to the scratching effect and drainage effect by the tread bubbles.

Examples of the blowing agent (b) include azodicarbonamide (ADCA), dinitrosopentamethylenetetramine (DNPT), dinitrosopentastyrenetetramine, benzenesulfonyl hydrazide derivative, p, p′-oxybisbenzenesulfonylhydrazide (OBSH), Ammonium bicarbonate, sodium bicarbonate, ammonium carbonate, nitrososulfonylazo compound, N, N'-dimethyl-N, N'-dinitrosophthalamide, toluenesulfonyl hydrazide, p-toluenesulfonyl semicarbazide, p, p'-oxybis Examples thereof include benzenesulfonyl semicarbazide. Among these foaming agents (b), dinitrosopentamethylenetetramine (DNPT) is preferable. These foaming agents (b) may be used individually by 1 type, and may use 2 or more types together.

The rubber composition of the present invention preferably contains 0.5 to 50 parts by mass, preferably 0.5 to 30 parts by mass of the foaming agent (b) with respect to 100 parts by mass of the rubber component (a). The content is more preferably 1 to 20 parts by mass, still more preferably 1 to 10 parts by mass. If the content of the foaming agent (b) is 0.5 parts by mass or more with respect to 100 parts by mass of the rubber component (a), air bubbles are sufficiently formed and the on-ice performance of the tire can be further improved. At the same time, the strain upon receiving an input increases, the effect of the above-mentioned multi-component copolymer (a1) increases, and the wear resistance of the tire can be further improved. Further, if the content of the foaming agent (b) is 50 parts by mass or less with respect to 100 parts by mass of the rubber component (a), the foamed rubber to be generated has sufficient strength. Since it can be improved and a sufficient contact area can be secured, the on-ice performance of the tire can be further improved.

Further, urea, zinc stearate, zinc benzenesulfinate, zinc white and the like are preferably used in combination with the foaming agent (b) as a foaming aid. These foaming aids may be used alone or in combination of two or more. By using a foaming aid in combination, the foaming reaction can be promoted to increase the degree of completion of the reaction, and unnecessary deterioration can be suppressed over time.
The content of the foaming aid is not particularly limited, but is preferably in the range of 1 to 30 parts by mass with respect to 100 parts by mass of the rubber component (a).

The rubber composition of the present invention preferably further contains hydrophilic short fibers (c). When the rubber composition contains the hydrophilic short fiber (c) and the foaming agent (b) described above, the gas generated from the foaming agent (b) during vulcanization penetrates into the hydrophilic short fiber (c), Bubbles having a shape corresponding to the shape of the hydrophilic short fibers (c) can be formed, and the walls of the bubbles are made hydrophilic by being covered with a resin derived from the hydrophilic short fibers. Therefore, when a tire is manufactured using a rubber composition containing hydrophilic short fibers (c) and a foaming agent (b) in the tread, the wall surface of the bubbles is exposed on the tread surface when the tire is used. As a result, the air bubbles can actively take in water, the tire has excellent drainage properties, and the on-ice performance of the tire can be greatly improved.

Examples of the hydrophilic resin used as a raw material for the hydrophilic short fiber (c) include resins having a hydrophilic group in the molecule, and specifically, at least selected from an oxygen atom, a nitrogen atom, and a sulfur atom. A resin containing one is preferable. For example, a resin containing at least one substituent selected from the group consisting of —OH, —COOH, —OCOR (R is an alkyl group), —NH ₂ , —NCO, and —SH can be mentioned. Of these substituents, —OH, —COOH, —OCOR, —NH ₂ , and —NCO are preferable. For example, ethylene-vinyl alcohol copolymer, vinyl alcohol homopolymer, poly (meth) acrylic acid or its ester, polyethylene glycol, carboxyvinyl copolymer, styrene-maleic acid copolymer, polyvinyl pyrrolidone, vinyl pyrrolidone-acetic acid Examples thereof include a vinyl copolymer and mercaptoethanol. Among these, an ethylene-vinyl alcohol copolymer, a vinyl alcohol homopolymer, and poly (meth) acrylic acid are preferable, and an ethylene-vinyl alcohol copolymer is particularly preferable.

The surface of the hydrophilic short fiber (c) has an affinity for the rubber component (a), and preferably comprises a low melting point resin having a melting point lower than the maximum vulcanization temperature of the rubber composition. A coating layer may be formed. By forming such a coating layer, the hydrophilic short fiber (c) has a good affinity for water while maintaining a good affinity between the coating layer and the rubber component (a). Dispersibility of the fiber into the rubber component (a) is improved. In addition, the low melting point resin melts during vulcanization to form a fluidized coating layer that contributes to adhesion between the rubber component (a) and the hydrophilic short fibers (c), and good drainage. It is possible to easily realize a tire imparted with durability and durability. The thickness of the coating layer may vary depending on the content of the hydrophilic short fibers (c), the average diameter, etc., but is usually 0.001 to 10 μm, preferably 0.001 to 5 μm.
The melting point of the low melting point resin used for the coating layer is preferably lower than the maximum temperature for vulcanization of the rubber composition. The maximum temperature for vulcanization means the maximum temperature that the rubber composition reaches when vulcanizing the rubber composition. For example, in the case of mold vulcanization, it means the maximum temperature that the rubber composition reaches from the time when the rubber composition enters the mold to the time when the rubber composition exits the mold and cools. It can be measured by embedding a thermocouple in the rubber composition. The upper limit of the melting point of the low melting point resin is not particularly limited, but is preferably selected in consideration of the above points, and is generally lower by 10 ° C. than the maximum vulcanization temperature of the rubber composition. Is preferable, and it is more preferably lower by 20 ° C. or more. The industrial vulcanization temperature of the rubber composition is generally about 190 ° C. at the maximum. For example, when the maximum vulcanization temperature is set to 190 ° C., the low melting point resin The melting point is usually selected within a range of less than 190 ° C, preferably 180 ° C or less, and more preferably 170 ° C or less.
The low melting point resin is preferably a polyolefin resin, and examples include polyethylene, polypropylene, polybutene, polystyrene, ethylene-propylene copolymer, ethylene-methacrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene- Examples thereof include propylene-diene terpolymers, ethylene-vinyl acetate copolymers, and ionomer resins thereof.

The hydrophilic short fiber (c) has an average length of preferably 0.1 to 50 mm, more preferably 1 to 7 mm, and an average diameter of preferably 1 μm to 2 mm, more preferably 5 μm to 0.5 mm. When the average length and the average diameter are within the above ranges, there is no possibility that the short fibers are entangled more than necessary, and good dispersibility can be ensured.
The content of the hydrophilic short fiber (c) is preferably in the range of 0.1 to 100 parts by mass, more preferably in the range of 1 to 50 parts by mass with respect to 100 parts by mass of the rubber component (a). By keeping the content of the hydrophilic short fiber (c) in the above range, a good balance between performance on ice and wear resistance can be achieved.

The rubber composition of the present invention preferably contains a softening agent (d). When the rubber composition contains the softening agent (d), the workability of the rubber composition is improved.

Examples of the softening agent (d) include mineral-derived mineral oil, petroleum-derived aromatic oil, paraffinic oil, naphthenic oil, and natural product-derived palm oil. Among these, from the viewpoint of the wear resistance of the rubber composition, mineral-derived softeners and petroleum-derived softeners are preferable.

As the softening agent, a mixture of naphthenic oil and asphalt or paraffinic oil is particularly preferable.
Here, in the mixture of naphthenic oil and asphalt, the naphthenic oil may be a hydrogenated naphthenic oil, and the hydrogenated naphthenic oil is preliminarily hydrogenated by a high-temperature high-pressure hydrorefining technique. It can be obtained by chemical purification. On the other hand, the asphalt content is preferably 5% by mass or less from the viewpoint of compatibility with the rubber component (a) and the effect as a softening agent. In addition, an asphaltene component is quantified from the composition analysis measured based on JPI method (Japan Petroleum Institute method).

The softener (d) preferably has an SP value of 4 or less, and more preferably 3 or less. If the SP value of the softening agent (d) is 4 or less, the softening agent (d) is locally present in the rubber composition and can be prevented from becoming fracture nuclei, and the wear resistance of the rubber composition can be reduced. Further improvement. In addition, although it does not specifically limit as a minimum of SP value of a softening agent (d), It is preferable that it is 0.01 or more.
Here, the SP value of the softening agent (d) means a solubility parameter calculated using Hansen's formula, and more specifically, among the three parameters of Hansen, the dipolar interaction between molecules. A numerical value calculated from the energy of action and the energy of hydrogen bonds.

The softening agent (d) preferably has a weight average molecular weight (Mw) of 2000 or less, more preferably 1500 or less. If the weight average molecular weight (Mw) of the softening agent (d) is 2000 or less, it can be suppressed that the softening agent (d) is locally present in the rubber composition and becomes a fracture nucleus. Abrasion resistance is further improved. In addition, although it does not specifically limit as a minimum of the weight average molecular weight (Mw) of a softening agent (d), It is preferable that it is 400 or more.
Here, the weight average molecular weight (Mw) of the softening agent (d) is a value in terms of polystyrene measured by gel permeation chromatography (GPC).

The content of the softening agent (d) is preferably in the range of 0.1 to 150 parts by weight, more preferably in the range of 1 to 130 parts by weight, with respect to 100 parts by weight of the rubber component (a). The range of parts by mass is even more preferable. When the content of the softening agent (d) is 0.1 parts by mass or more with respect to 100 parts by mass of the rubber component (a), the workability of the rubber composition is further improved. If present, the abrasion resistance of the rubber composition is further improved.

The rubber composition of the present invention preferably contains a resin component (e). When the rubber composition contains the resin component (e), the workability of the rubber composition is further improved. Further, since the rubber composition contains the resin component (e) together with the multi-component copolymer (a1), high wear resistance derived from the multi-component copolymer (a1) is maintained, and molding of a tire or the like is performed. In some cases, it is possible to provide a rubber composition having excellent tackiness when bonded to other members, leading to an improvement in productivity of tires and the like.

As the resin component (e), various natural resins and synthetic resins can be used. Specifically, rosin resins, terpene resins, petroleum resins, phenol resins, coal resins, xylene resins. It is preferable to use a resin or the like. These resin components (e) may be used individually by 1 type, and may use 2 or more types together.

In the natural resin, examples of the rosin resin include gum rosin, tall oil rosin, wood rosin, hydrogenated rosin, disproportionated rosin, polymerized rosin, modified rosin glycerin, and pentaerythritol ester.

In the natural resin, examples of the terpene resin include α-pinene-based, β-pinene-based, dipentene-based terpene resins, aromatic modified terpene resins, terpene phenol resins, hydrogenated terpene resins, and the like.
Among these natural resins, a polymerized rosin, a terpene phenol resin, and a hydrogenated terpene resin are preferable from the viewpoint of wear resistance of the blended rubber composition.

In the synthetic resin, the petroleum-based resin is a cracked oil fraction containing unsaturated hydrocarbons such as olefins and diolefins by-produced together with petrochemical basic raw materials such as ethylene and propylene by, for example, thermal decomposition of naphtha in the petrochemical industry. Is obtained by polymerizing with a Friedel-Crafts catalyst in the form of a mixture. Examples of the petroleum resin include aliphatic petroleum resins obtained by (co) polymerization of C ₅ fraction obtained by thermal decomposition of naphtha (hereinafter sometimes referred to as “C ₅ resin”), naphtha. Aromatic petroleum resin obtained by (co) polymerization of the C ₉ fraction obtained by thermal decomposition of the above (hereinafter also referred to as “C ₉ resin”), the C ₅ fraction and the C ₉ fraction Copolymer petroleum resin (hereinafter sometimes referred to as “C ₅ -C ₉ resin”) obtained by copolymerizing the components, alicyclic compound petroleum resins such as hydrogenated and dicyclopentadiene Styrene resin such as styrene, substituted styrene, or a copolymer of styrene and another monomer.

C ₅ fractions obtained by thermal decomposition of naphtha are usually olefins such as 1-pentene, 2-pentene, 2-methyl-1-butene, 2-methyl-2-butene and 3-methyl-1-butene. These include hydrocarbons, diolefin hydrocarbons such as 2-methyl-1,3-butadiene, 1,2-pentadiene, 1,3-pentadiene, 3-methyl-1,2-butadiene and the like. The aromatic petroleum resin obtained by (co) polymerizing the C ₉ fraction is a resin obtained by polymerizing a 9-carbon aromatic having vinyltoluene and indene as main monomers, and is obtained by thermal decomposition of naphtha. Specific examples of the C ₉ fraction obtained include styrene homologues such as α-methylstyrene, β-methylstyrene, and γ-methylstyrene, and indene homologues such as indene and coumarone. Trade names include Petrogin made by Mitsui Petrochemical, Petlite made by Mikuni Chemical, Neopolymer made by Nippon Petrochemical, Petol made by Toyo Soda, etc.

Furthermore, in the present invention can be in terms of workability, it is suitably used modified petroleum resin modified petroleum resin comprising the C ₉ fraction. Examples of the modified petroleum resin, an unsaturated alicyclic compound modified with C ₉ petroleum resins, C ₉ petroleum resins modified with a compound having a hydroxyl group, C ₉ petroleum resins modified with an unsaturated carboxylic acid compound Can be mentioned.

Preferred unsaturated alicyclic compounds include cyclopentadiene, methylcyclopentadiene and the like. Further, as the unsaturated alicyclic compound, a Diels-Alder reaction product of alkylcyclopentadiene is also preferable. And tricyclopentadiene. As the unsaturated alicyclic compound, dicyclopentadiene is particularly preferable. The dicyclopentadiene-modified C ₉ petroleum resin can be obtained by thermal polymerization or the like in the presence of both dicyclopentadiene and C ₉ fraction. Examples of the dicyclopentadiene-modified C ₉ petroleum resin include Neopolymer 130S (manufactured by Nippon Petrochemical Co., Ltd.).

Examples of the compound having a hydroxyl group include alcohol compounds and phenol compounds. Specific examples of the alcohol compound include alcohol compounds having a double bond such as allyl alcohol and 2-butene-1,4 diol. As the phenol compound, alkylphenols such as phenol, cresol, xylenol, p-tert-butylphenol, p-octylphenol and p-nonylphenol can be used. These compounds having a hydroxyl group may be used alone or in combination of two or more. In addition, a C ₉ petroleum resin having a hydroxyl group is a method in which an ester group is introduced into a petroleum resin by thermally polymerizing a (meth) acrylic acid alkyl ester together with a petroleum fraction, and then the ester group is reduced. It can be produced by a method of hydrating the double bond after remaining or introducing the double bond therein. As the C ₉ -based petroleum resin having a hydroxyl group, those obtained by various methods as described above can be used. From the viewpoint of performance and production, it is preferable to use a phenol-modified petroleum resin or the like. The phenol-modified petroleum resin is obtained by cationic polymerization of a C ₉ fraction in the presence of phenol, is easily modified, and is inexpensive. Examples of the phenol-modified C ₉ petroleum resin include Neopolymer E-130 (manufactured by Shin Nippon Petrochemical).

Furthermore, the modified C ₉ petroleum resin with an unsaturated carboxylic acid compound is capable of modifying the C ₉ petroleum resin in an ethylenically unsaturated carboxylic acid. Typical examples of such ethylenically unsaturated carboxylic acids include (anhydrous) maleic acid, fumaric acid, itaconic acid, tetrahydro (anhydrous) phthalic acid, (meth) acrylic acid or citraconic acid. Unsaturated carboxylic acid-modified C ₉ petroleum resin can be obtained by thermally polymerizing C ₉ petroleum resin and ethylenically unsaturated carboxylic acid. In the present invention, maleic acid-modified C ₉ petroleum resin is preferable. Examples of the unsaturated carboxylic acid-modified C ₉ petroleum resin include Neopolymer 160 (manufactured by Shin Nippon Petrochemical).

Further, in the present invention can be suitably used C ₅ fraction and C ₉ fraction copolymer resin obtained by thermal cracking of naphtha. Here, the C ₉ fraction is not particularly limited, but is preferably a C ₉ fraction obtained by thermal decomposition of naphtha. Specific examples include TS30, TS30-DL, TS35, TS35-DL, etc., from the STRILL series manufactured by SCHILL & SEILACHER.

In the synthetic resin, examples of the phenolic resin include alkylphenol formaldehyde resins and rosin-modified products thereof, alkylphenolacetylene resins, modified alkylphenol resins, terpenephenol resins, and the like. Hitachi Chemical Co., Ltd.), and p-tert-butylphenol acetylene resin colesin (BASF).

In the synthetic resin, the coal-based resin includes coumarone indene resin and the like, and the xylene-based resin in the synthetic resin includes xylene formaldehyde resin and the like. Other polybutenes can also be used as the resin component. Among these synthetic resins, aromatic from the viewpoint of abrasion resistance of the compounded rubber composition, C ₅ fraction and C ₉ fraction copolymer resin, obtained by a C ₉ fraction (co) polymerizing Group petroleum resins, phenolic resins and coumarone indene resins are preferred.

The resin component (e) preferably has an SP value of 4 or less, and more preferably 3 or less. If the SP value of the resin component (e) is 4 or less, it can be suppressed that the resin component (e) is locally present in the rubber composition and becomes a fracture nucleus, and the wear resistance of the rubber composition is reduced. Further improvement. The lower limit of the SP value of the resin component (e) is not particularly limited, but is preferably 0.01 or more.
Here, the SP value of the resin component (e) means a solubility parameter calculated using Hansen's formula, and more specifically, among the three parameters of Hansen, the dipole mutual relationship between molecules. A numerical value calculated from the energy of action and the energy of hydrogen bonds.

The resin component (e) preferably has a weight average molecular weight (Mw) of 2000 or less, and more preferably 1500 or less. If the weight average molecular weight (Mw) of the resin component (e) is 2000 or less, in the rubber composition, it can be suppressed that the resin component (e) is locally present and becomes a fracture nucleus. Abrasion resistance is further improved. The lower limit of the weight average molecular weight (Mw) of the resin component (e) is not particularly limited, but is preferably 400 or more.
Here, the weight average molecular weight (Mw) of the resin component (e) is a value in terms of polystyrene measured by gel permeation chromatography (GPC).

The resin component (e) is preferably a resin having a softening point of 200 ° C. (measurement method: ASTM E28-58-T) or less, more preferably in the range of 80 ° C. to 150 ° C., 90 The range of from 0 to 120 ° C. is even more preferable. When the softening point is 200 ° C. or less, the temperature dependence of the hysteresis loss characteristic is small, and the workability is further improved.

The content of the resin component (e) is preferably in the range of 5 to 150 parts by weight, more preferably in the range of 5 to 100 parts by weight, with respect to 100 parts by weight of the rubber component (a). Is more preferable, and the range of 10 to 50 parts by mass is particularly preferable. If the content of the resin component (e) is 5 parts by mass or more with respect to 100 parts by mass of the rubber component (a), the tackiness and wear resistance of the rubber composition are further improved, and 150 parts by mass or less. If it is, the workability | operativity of a rubber composition can be maintained favorable.

The rubber composition of the present invention preferably contains a filler (f). When a rubber composition contains a filler (f), the reinforcement property of a rubber composition can be improved. The filler (f) is not particularly limited, and carbon black, silica, aluminum hydroxide, clay, alumina, talc, mica, kaolin, glass balloon, glass beads, calcium carbonate, magnesium carbonate, magnesium hydroxide, oxidation Magnesium, titanium oxide, potassium titanate, barium sulfate and the like can be mentioned. Among these, carbon black, silica and aluminum hydroxide are preferable, and carbon black and silica are more preferable. These may be used alone or in combination of two or more.

Examples of the carbon black include GPF, FEF, HAF, ISAF, and SAF grade carbon black.
Examples of the silica include wet silica (hydrous silicic acid), dry silica (anhydrous silicic acid), calcium silicate, aluminum silicate, and the like. Among these, wet silica is preferable.
Moreover, as said aluminum hydroxide, it is preferable to use Heidilite (registered trademark, Showa Denko Co., Ltd.) etc.

The content of the filler (f) is not particularly limited and may be appropriately selected depending on the intended purpose. However, it is preferably 10 to 120 parts by weight, preferably 20 to 100 parts by mass is more preferable, and 30 to 80 parts by mass is particularly preferable. When the content of the filler (f) is 10 parts by mass or more, the effect of improving the reinforcing property by the filler (f) is sufficiently obtained, and when the content is 120 parts by mass or less, good work is achieved. Sex can be maintained.

The rubber composition of the present invention preferably further contains a silane coupling agent (g) in order to improve the effect of the silica. The silane coupling agent (g) is not particularly limited, and examples thereof include bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, and bis (3-trimethyl). Ethoxysilylpropyl) disulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilyl Propyl-N, N-dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothia Zolyl tetrasulfide, 3-triethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl -N, N-dimethylthiocarbamoyl tetrasulfide, dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide and the like. These silane coupling agents may be used alone or in combination of two or more.

The content of the silane coupling agent (g) is preferably in the range of 2 to 20 parts by mass, more preferably in the range of 5 to 15 parts by mass with respect to 100 parts by mass of the silica. When the content of the silane coupling agent is 2 parts by mass or more with respect to 100 parts by mass of silica, the effect of silica is sufficiently improved, and the content of the silane coupling agent is 20 with respect to 100 parts by mass of silica. If it is below mass parts, the possibility of gelation of the rubber component (a) is low.

The rubber composition of the present invention preferably contains a crosslinking agent (h). There is no restriction | limiting in particular as this crosslinking agent (h), According to the objective, it can select suitably, For example, a sulfur type crosslinking agent, an organic peroxide type crosslinking agent, an inorganic crosslinking agent, a polyamine crosslinking agent, resin crosslinking Agents, sulfur compound crosslinking agents, oxime-nitrosamine crosslinking agents and the like. In addition, as a rubber composition for tires, a sulfur-based crosslinking agent (vulcanizing agent) is more preferable among these.
The content of the crosslinking agent (h) is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.1 to 20 parts by mass with respect to 100 parts by mass of the rubber component (a).

When using the vulcanizing agent, a vulcanization accelerator (i) can be used in combination. Examples of the vulcanization accelerator (i) include guanidine, aldehyde-amine, aldehyde-ammonia, thiazole, sulfenamide, thiourea, thiuram, dithiocarbamate, and xanthate compounds. It is done.

In addition, the rubber composition of the present invention includes a vulcanization aid, a colorant, a flame retardant, a lubricant, a plasticizer, a processing aid, an anti-aging agent, an anti-scorch agent, an anti-ultraviolet agent, and an antistatic agent as necessary. Known agents such as a colorant, an anti-coloring agent, and other compounding agents can be used depending on the purpose of use.

<Foamed rubber>
The foamed rubber of the present invention is characterized by foaming the above rubber composition. By applying the foamed rubber of the present invention to a tire tread, both the performance on ice and the wear resistance of the tire can be improved.
In addition, since the rubber composition of this invention mentioned above contains a foaming agent (b), the bubble derived from a foaming agent (b) is formed at the time of vulcanization | cure, and becomes foamed rubber (vulcanized rubber).

The foamed rubber of the present invention preferably has a foaming rate of 5 to 80%, more preferably 5 to 70%, still more preferably 10 to 60%, and even more preferably 10 to 50%. Is particularly preferred. If the foaming ratio is 5% or more, bubbles can be sufficiently formed to further improve the on-ice performance of the tire, and distortion upon receiving an input increases, so that the above-mentioned multi-component copolymer ( The effect of a1) is increased, and the wear resistance of the tire can be further improved. Further, if the foaming rate is 80% or less, the foamed rubber to be generated has sufficient strength, so that the wear resistance of the tire can be further improved, and a sufficient ground contact area can be secured. The performance on ice can be further improved.

The foaming ratio of the foamed rubber used for the tire tread is usually about 1 to 30%. However, since the foamed rubber of the present invention contains the above-described multi-component copolymer (a1), Even if the foaming rate is high (for example, 40% or more), the performance on ice and the wear resistance can be highly compatible.

Here, the foaming ratio of the foamed rubber means an average foaming ratio Vs, and specifically means a value calculated by the following formula (XXI).
Vs = (ρ ₀ / ρ ₁ −1) × 100 (%) (XXI)
In the formula (XXI), ρ ₁ represents the density (g / cm ³ ) of the foam rubber (vulcanized rubber), and ρ ₀ represents the density (g / cm ³ ) of the solid phase part in the foam rubber (vulcanized rubber). Show. The density of the foam rubber and the density of the solid phase part of the foam rubber are calculated from the mass in ethanol and the mass in air. Further, the foaming rate can be appropriately changed depending on the type and content of the foaming agent (b) and foaming aid.

The foamed rubber of the present invention can be used for various foamed rubber products such as shoe soles in addition to the tire tread described later.

<Tire tread>
The tire tread of the present invention is characterized by using the above foamed rubber. Since the tire tread of the present invention uses the above-described foamed rubber, it can improve both the on-ice performance and the wear resistance of the tire when applied to a tire.
Note that the tire tread of the present invention may be applied to a new tire or a retread tire.

<Tire>
The tire of the present invention is characterized by using the above-described tire tread. Since the tire of the present invention uses the above-described tire tread, it is excellent in both on-ice performance and wear resistance.
The tire of the present invention is particularly useful as a winter tire such as a studless tire because it is excellent in both on-ice performance and wear resistance.
The tire of the present invention may be obtained by vulcanization after molding using an unvulcanized rubber composition according to the type and member of the tire to be applied, or semi-vulcanized rubber that has undergone a preliminary vulcanization process or the like. It may be obtained by further vulcanization after use. In addition, as gas with which a tire is filled, inert gas, such as nitrogen, argon, helium other than the air which adjusted normal or oxygen partial pressure, can be used.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

<Method for analyzing copolymer>
The number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the copolymer synthesized as described below by the following method, butadiene unit, ethylene unit and styrene unit content, The main chain structure was confirmed by measuring the melting point, endothermic peak energy, glass transition temperature, and crystallinity.

(1) Number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn)
Monodispersed polystyrene was analyzed by gel permeation chromatography [GPC: HLC-8121GPC / HT manufactured by Tosoh Corporation, column: GMH _HR -H (S) HT × 2 manufactured by Tosoh Corporation, detector: differential refractometer (RI)]. As a reference, the polystyrene-equivalent number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the copolymer were determined. The measurement temperature is 40 ° C.

(2) Content of butadiene unit, ethylene unit, and styrene unit The content (mol%) of butadiene unit, ethylene unit, and styrene unit in the copolymer was determined by ¹ H-NMR spectrum (100 ° C., d-tetrachloroethane standard). : 6 ppm) from the integration ratio of each peak.

(3) Melting point ( _Tm )
The melting point of the copolymer was measured according to JIS K 7121-1987 using a differential scanning calorimeter (DSC, “DSCQ2000” manufactured by TA Instruments Japan Co., Ltd.).

(4) Endothermic peak energy Using a differential scanning calorimeter (DSC, manufactured by T.A. Instruments Japan, “DSCQ2000”), the rate of temperature increase was 10 ° C./min according to JIS K 7121-1987. The temperature was raised from −150 ° C. to 150 ° C., and the endothermic peak energy at 0 to 120 ° C. at that time (1st run) was measured.

(5) Glass transition temperature (Tg)
The glass transition temperature (Tg) of the copolymer was measured in accordance with JIS K 7121-1987 using a differential scanning calorimeter (DSC, “DSCQ2000” manufactured by TA Instruments Japan).

(6) Crystallinity The crystal melting energy of 100% crystalline polyethylene and the melting peak energy of the obtained copolymer were measured, and the crystallinity was calculated from the energy ratio of polyethylene and copolymer. The melting peak energy was measured with a differential scanning calorimeter (DSC, manufactured by TA Instruments Japan, “DSCQ2000”).

(7) Confirmation of main chain structure The synthesized copolymer was measured for ¹³ C-NMR spectrum.

<Synthesis Method of Ternary Copolymer>
To a sufficiently dried 1000 mL pressure-resistant stainless steel reactor, 160 g of styrene and 600 mL of toluene were added.
Mono (bis (1,3-tert-butyldimethylsilyl) indenyl) bis (bis (dimethylsilyl) amidogadolinium complex {1,3-[(t-Bu)) in a glass container in a glove box under a nitrogen atmosphere Me ₂ Si] ₂ C ₉ H ₅ Gd [N (SiHMe ₂ ) ₂ ] ₂ } 0.25 mmol, dimethylanilinium tetrakis (pentafluorophenyl) borate [Me ₂ NHPhB (C ₆ F ₅ ) ₄ ] 0.275 mmol, And 1.1 mmol of diisobutylaluminum hydride were charged and dissolved in 40 mL of toluene to obtain a catalyst solution.
The catalyst solution was added to the pressure resistant stainless steel reactor and heated to 70 ° C.
Next, ethylene was charged into the pressure resistant stainless steel reactor at a pressure of 1.5 MPa, and further 80 mL of a toluene solution containing 20 g of 1,3-butadiene was charged into the pressure resistant stainless steel reactor over 8 hours. Copolymerization was carried out for 5 hours.
Next, 1 ml of 2,2′-methylene-bis (4-ethyl-6-tert-butylphenol) (NS-5) 5 mass% isopropanol solution was added to the pressure resistant stainless steel reactor to stop the reaction.
Next, the copolymer was separated using a large amount of methanol and vacuum-dried at 50 ° C. to obtain a terpolymer.
About the obtained terpolymer, number average molecular weight (Mn), weight average molecular weight (Mw), molecular weight distribution (Mw / Mn), butadiene unit, ethylene unit, styrene unit content, melting point (T _m ), Endothermic peak energy, glass transition temperature (Tg), and crystallinity were measured by the above methods. The results are shown in Table 1.
Further, when the main chain structure of the obtained ternary copolymer was confirmed by the above method, no peak was observed at 10 to 24 ppm in the ¹³ C-NMR spectrum chart. The polymer was confirmed to have a main chain consisting only of an acyclic structure.

<Synthesis Method of Binary Copolymer>
After adding 2,000 g of a toluene solution containing 120 g (2.22 mol) of 1,3-butadiene to a sufficiently dry 4 L stainless steel reactor, ethylene is introduced at 1.72 MPa. On the other hand, bis (2-phenylindenyl) gadolinium bis (dimethylsilylamide) [(2-PhC ₉ H ₆ ) ₂ GdN (SiHMe ₂ ) ₂ ] 28.5 μmol in a glass container in a glove box under a nitrogen atmosphere. , 28.5 μmol of dimethylanilinium tetrakis (pentafluorophenyl) borate [Me ₂ NHPhB (C ₆ F ₅ ) ₄ ] and 2.00 mmol of diisobutylaluminum hydride are dissolved in 40 ml of toluene to obtain a catalyst solution. Thereafter, the catalyst solution is taken out from the glove box, an amount of 25.0 μmol in terms of gadolinium is added to the monomer solution, and polymerization is performed at 50 ° C. for 90 minutes. After the polymerization, 5 ml of 2,2′methylene-bis (4-ethyl-6-t-butylphenol) (NS-5) 5% by mass isopropanol solution was added to stop the reaction, and the copolymer was further added with a large amount of methanol. Separate and vacuum dry at 70 ° C. to obtain a binary copolymer.
About the obtained binary copolymer, number average molecular weight (Mn), weight average molecular weight (Mw), molecular weight distribution (Mw / Mn), butadiene unit, ethylene unit content, melting point (T _m ), endothermic peak energy, The glass transition temperature (Tg) and the crystallinity are measured by the above methods. The results are shown in Table 1.

<Method for producing hydrophilic short fiber>
According to Production Example 3 disclosed in JP 2012-219245 A, using two twin-screw extruders, 40 parts by mass of polyethylene [manufactured by Nippon Polyethylene, Novatec HJ360 (MFR5.5, melting point 132 ° C.)] as a hopper, 40 parts by mass of an ethylene-vinyl alcohol copolymer [Kuraray Co., Ltd., Eval F104B (MFR4.4, melting point: 183 ° C.)] was extruded at the same time from the die outlet, Cut into 2 mm, hydrophilic short fibers were produced in which a coating layer made of polyethylene was formed on the surface of the core made of an ethylene-vinyl alcohol copolymer.

<Preparation and evaluation of rubber composition>
(Examples 1 to 5 and Comparative Examples 1 to 5)
According to the formulation shown in Table 2, a rubber composition was produced using a normal Banbury mixer. The obtained rubber composition was vulcanized at 160 ° C. for 15 minutes to produce a vulcanized rubber, and the foaming rate of the vulcanized rubber was measured by the following method. And the performance on ice was evaluated. The results are shown in Table 2.

(8) Foaming ratio The density ρ ₁ (g / cm ³ ) of the vulcanized rubber (foamed rubber) and the density ρ ₀ (g / cm ³ ) of the solid phase part in the vulcanized rubber (foamed rubber) were measured, and the above The foaming rate (average foaming rate Vs,%) was calculated according to the formula (XXI).

(9) Abrasion resistance The amount of wear of the vulcanized rubber was measured according to the B method of the sliding wear test of JIS K 7218: 1986. The measurement temperature was room temperature (23 ° C.) and the load was 16N. The reciprocal of the amount of wear of the vulcanized rubber of Comparative Example 5 was taken as 100 and expressed as an index. The larger the index value, the smaller the wear amount and the better the wear resistance.

(10) On-ice performance The frictional force generated when a vulcanized rubber having a diameter of 50 mm and a thickness of 10 mm was pressed against fixed ice and rotated was detected with a load cell, and the dynamic friction coefficient μ was calculated. The measurement temperature was −2 ° C., the surface pressure was 12 kgf / cm ² , and the sample rotation peripheral speed was 20 cm / sec. The dynamic friction coefficient μ of Comparative Example 5 was taken as 100 and displayed as an index. The larger the index value, the larger the dynamic friction coefficient μ, indicating better performance on ice.

(Comparative Example 6)
According to the formulation shown in Table 2, a rubber composition is produced using an ordinary Banbury mixer. The resulting rubber composition is vulcanized at 160 ° C. for 15 minutes to produce a vulcanized rubber. Evaluate performance on ice. The results are shown in Table 2.

* 1 Natural rubber: TSR20
* 2 Butadiene rubber: Product name “BR01” manufactured by JSR Corporation
* 3 Ternary copolymer: Ternary copolymer synthesized by the above method * 4 Binary copolymer: Binary copolymer synthesized by the above method * 5 Carbon black: SAF grade carbon black, Asahi Carbon Product name "ASAHI # 105"
* 6 Process oil: Petroleum hydrocarbon process oil, manufactured by Idemitsu Kosan Co., Ltd., trade name "DAIAANA PROCESS OIL NS-28"
* 7 Silica: Tosoh Silica Industry Co., Ltd., trade name “Nipsil AQ”
* 8 Silane coupling agent: Bistriethoxysilylpropyl polysulfide, manufactured by Shin-Etsu Chemical Co., Ltd. * 9 Wax: Microcrystalline wax, manufactured by Seiko Chemical Co., Ltd. * 10 Anti-aging agent: Ouchi Shinsei Chemical Co., Ltd., trade name “NOCRACK 6C”
* 11 Resin: Aliphatic hydrocarbon resin, manufactured by Mitsui Petrochemical Co., Ltd., trade name “HI-REZ G-100X”
* 12 Hydrophilic short fiber: hydrophilic short fiber prepared by the above method * 13 Zinc oxide: manufactured by Hux Itec Corp. * 14 Vulcanization accelerator CZ: N-cyclohexyl-2-benzothiazolylsulfenamide, Ouchi Shinsei Chemical Product name "Noxeller CZ", manufactured by Kogyo Co., Ltd.
* 15 Vulcanization accelerator MBTS: Di-2-benzothiazolyl disulfide, manufactured by Ouchi Shinsei Chemical Industry Co., Ltd., trade name “Noxeller DM-P”
* 16 Foaming agent: dinitrosopentamethylenetetramine, manufactured by Sankyo Kasei Co., Ltd., trade name "Cermic AN"

From the results of the examples shown in Table 2, it can be seen that the rubber compositions of the examples according to the present invention are excellent in both wear resistance and performance on ice.

The rubber composition and foamed rubber of the present invention can be used for treads of tires, particularly studless tires. The tire of the present invention is particularly useful as a studless tire.

Claims (17)

A rubber component (a) including a multi-component copolymer (a1) containing a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit;
A foaming agent (b);
A rubber composition comprising: The multi-component copolymer (a1) has a content of the conjugated diene unit of 1 to 50 mol%, a content of the non-conjugated olefin unit of 40 to 97 mol%, and a content of the aromatic vinyl unit of 2 The rubber composition according to claim 1, wherein the rubber composition is ˜35 mol%. The rubber composition according to claim 1 or 2, comprising 0.5 to 50 parts by mass of the foaming agent (b) with respect to 100 parts by mass of the rubber component (a). The rubber composition according to any one of claims 1 to 3, further comprising a hydrophilic short fiber (c). The rubber composition according to any one of claims 1 to 4, wherein the multi-component copolymer (a1) has a melting point of 30 to 130 ° C measured by a differential scanning calorimeter (DSC). The multi-component copolymer (a1) according to any one of claims 1 to 5, wherein the endothermic peak energy measured with a differential scanning calorimeter (DSC) at 0 to 120 ° C is 10 to 150 J / g. Rubber composition. The rubber composition according to any one of claims 1 to 6, wherein the multi-component copolymer (a1) has a glass transition temperature of 0 ° C or less as measured by a differential scanning calorimeter (DSC). The rubber composition according to any one of claims 1 to 7, wherein the multi-component copolymer (a1) has a crystallinity of 0.5 to 50%. The rubber composition according to any one of claims 1 to 8, wherein in the multi-component copolymer (a1), the non-conjugated olefin unit is an acyclic non-conjugated olefin unit. 10. The rubber composition according to claim 9, wherein the non-cyclic non-conjugated olefin unit comprises only an ethylene unit. The rubber composition according to any one of claims 1 to 10, wherein in the multi-component copolymer (a1), the aromatic vinyl unit includes a styrene unit. The rubber composition according to any one of claims 1 to 11, wherein in the multi-component copolymer (a1), the conjugated diene unit includes a 1,3-butadiene unit and / or an isoprene unit. The rubber composition according to any one of claims 1 to 12, wherein the content of the multi-component copolymer (a1) in the rubber component (a) is 5 to 100% by mass. A foamed rubber obtained by foaming the rubber composition according to any one of claims 1 to 13. The foamed rubber according to claim 14, wherein the foaming rate is 5 to 80%. A tire tread characterized by using the foamed rubber according to claim 14 or 15. A tire using the tire tread according to claim 16.