JP2019218561A - Thermoplastic elastomer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer resin composition which is excellent in flexibility and fusion property to a polar resin, suppresses surface stickiness, and is also excellent in wear resistance, and a composite molded body in which the composition is fused to a member. .. SOLUTION: The thermoplastic styrene elastomer A, the softening agent B, and the thermoplastic polyester elastomer C are contained, and A has a styrene monomer unit content of 10 to 50% by mass and Thermal with a weight average molecular weight of 200,000 to 500,000, B kinematic viscosity at 40 ° C. of 30 to 500 mm2 / s, and C containing hard and soft segments in a mass ratio of 10/90 to 30/70. A thermoplastic elastomer composition and a composite molded body in which the composition is fused to a member. [Selection diagram] Fig. 1

Description

The present invention relates to a thermoplastic elastomer composition useful for various molded articles such as electronic materials, home appliances, electric appliances, medical tools, packaging materials, stationery and miscellaneous goods, and a composite molded article obtained by fusing the composition to a member. .

As a useful composition for various molded articles such as automobiles, electronic materials, home appliances, electric appliances, medical tools, packaging materials, stationery, tools, and miscellaneous goods, a thermoplastic elastomer composition containing a polyester-based elastomer and a styrene-based elastomer is used. Proposed. This thermoplastic elastomer composition is required to have various physical properties depending on the use of the molded article. For example, in order to use it for grip rubbers such as pen grips and electric tool grips, it is necessary to obtain good formability, fusion property to polar resin such as polycarbonate constituting the composite material main body, and good tactile sensation. It is required to have flexibility, abrasion resistance so that it does not wear even when repeatedly gripped.

Patent Document 1 includes a hydrogenated derivative of a block copolymer composed of a polymer block of a monovinyl-substituted aromatic hydrocarbon and a conjugated diene polymer block, and a polyester-based copolymer elastomer. An invention is disclosed relating to a thermoplastic elastomer composition that may contain a softener. Such a composition is said to have good heat-fusibility to a hard resin, but only a softener is disclosed to be important for adjusting the hardness and the melt fluidity during molding. The effect of the softener on the adhesion is not disclosed.

JP-A-10-130451

Thermoplastic elastomer compositions containing a polyester-based thermoplastic elastomer and a hydrogenated styrene-based thermoplastic elastomer have been known for some time, and it is also known that they can be fused to polar resins such as polycarbonate resins, but the mechanism of action is apparent. Rather, it is difficult to select a composition that has high fusion strength, excellent flexibility, and avoids problems such as surface stickiness.

An object of the present invention is to provide a thermoplastic elastomer resin composition having excellent flexibility and fusion property to a polar resin, suppressing surface stickiness, and also having excellent abrasion resistance, and a composite molding in which the composition is fused to a member. Is to provide the body.

The present invention
[1] comprising a thermoplastic styrene-based elastomer A, a softener B, and a thermoplastic polyester-based elastomer C,
The thermoplastic styrene-based elastomer A has a styrene-based monomer unit content of 10 to 50% by mass, and a weight average molecular weight of 200,000 to 500,000,
The kinematic viscosity at 40 ° C. of the softener B is 30 to 500 mm ² / s,
The thermoplastic polyester elastomer C contains a hard segment and a soft segment in a mass ratio of 10/90 to 30/70 (hard segment / soft segment),
With respect to 100 parts by mass of the thermoplastic styrene-based elastomer A, 20 to 200 parts by mass of the softening agent B, and with respect to 100 parts by mass of the total amount of the thermoplastic styrene-based elastomer A and the softening agent B, A thermoplastic elastomer composition comprising 60 to 300 parts by mass of a polyester elastomer C,
[2] A composite molded article obtained by fusing the thermoplastic elastomer composition according to the above [1] to a polar resin.

The thermoplastic elastomer composition of the present invention has an effect of being excellent in flexibility and fusion property to a polar resin, suppressing surface stickiness, and being excellent in abrasion resistance.

4 is an electron micrograph of a cross section of the thermoplastic elastomer composition obtained in Example 4. 4 is an electron micrograph of a cross section of the thermoplastic elastomer composition obtained in Comparative Example 1.

The thermoplastic elastomer composition of the present invention contains a thermoplastic styrene-based elastomer A, a softener B, and a thermoplastic polyester-based elastomer C.

Although the thermoplastic elastomer composition of the present invention is excellent in the adhesiveness to a polar resin, the abrasion resistance, and the suppression of surface stickiness, it is presumed that this is largely due to the phase structure of the thermoplastic elastomer composition. That is, the thermoplastic elastomer composition of the present invention has a phase separation structure in which a dispersed phase composed of the thermoplastic styrene elastomer A and the softener B is present in a continuous phase composed of the thermoplastic polyester elastomer C, The thermoplastic polyester-based elastomer C having high strength and high compatibility with the polar resin becomes a continuous phase exposed to the surface, so that the abrasion resistance and the fusion property to the polar resin are improved, and the thermoplastic styrene-based elastomer is improved. Since the solution of A and the softener B becomes a dispersed phase and is surrounded by a continuous phase, bleed out of the softener B is inhibited, and stickiness on the surface is suppressed.
Therefore, in the present invention, so that the thermoplastic polyester-based elastomer C is a continuous phase,
The molecular weight of the thermoplastic styrene-based elastomer A is set higher because the composition ratio of the three components is set, and the higher the melt viscosity, the more easily the dispersed phase becomes. In the thermoplastic styrene-based elastomer A, the ratio of the styrene block, which is a hard segment, is set to be low so that the thermoplastic styrene-based elastomer A and the softener B are compatible.

The thermoplastic styrene-based elastomer A is composed of a block unit (s1) of a polymer composed of a styrene monomer and a block unit (b1) of a polymer composed of a conjugated diene compound from the viewpoint of flexibility and moldability. It is preferably a block copolymer (Z1).

Styrene monomers constituting the block unit (s1) include styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, And vinyl anthracene.

The block copolymer (Z1) is composed of a hard part (hard segment) composed of block units (s1) and a soft part (soft segment) composed of block units (b1). From the viewpoint of determining the overall physical properties, The content of the styrene monomer unit in the block copolymer (Z1) is 10 to 50% by mass, and more preferably 15 to 40% by mass.

The conjugated diene compound constituting the block unit (b1) includes butadiene, isoprene,
1,3-pentadiene and the like.

The block copolymer (Z1) is preferably partially or wholly hydrogenated because hydrogenation reduces unsaturated bonds and improves heat resistance, weather resistance and mechanical properties. . The hydrogenation rate is preferably 80% or more, more preferably 90% or more. In the present invention, the hydrogenation rate is the content of carbon-carbon double bonds derived from the conjugated diene compound in the block copolymer, before and after hydrogenation, measured by ¹ H-NMR spectrum, the measured value Can be obtained from

Specific examples of the hydrogenated product of the block copolymer (Z1) include a styrene-ethylene / butylene block copolymer, a styrene-ethylene / butylene-styrene block copolymer, a styrene-ethylene / propylene block copolymer, and styrene. -Ethylene-propylene-styrene block copolymer, styrene-ethylene-ethylene-propylene block copolymer,
Styrene-ethylene-ethylene-propylene-styrene block copolymer, styrene-isobutylene block copolymer, styrene-isobutylene-styrene block copolymer, (
α-methylstyrene) -ethylene / butylene block copolymer, (α-methylstyrene) -ethylene / butylene- (α-methylstyrene) block copolymer, and the like. They are,
Even if alone, it may be a mixture of two or more, from the viewpoint of raw material preparation and workability,
Group consisting of styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer (SEPS), and styrene-ethylene-ethylene-propylene-styrene block copolymer (SEEPS) At least one selected from these is preferable, and SEBS and / or SEEPS is more preferable.

The thermoplastic styrene-based elastomer A is preferably not acid-modified from the viewpoint that various properties are industrially produced in large quantities and are easily available.

The weight average molecular weight of the thermoplastic styrene-based elastomer A is 200,00 from the viewpoint of using the thermoplastic styrene-based elastomer A as a disperse phase and improving abrasion resistance and fusion property to a polar resin.
0 or more, preferably 300,000 or more, from the viewpoint of moldability, 500,000 or less, preferably 450
, 000 or less. When the thermoplastic elastomer A is composed of a plurality of elastomers, the weighted average value of the weight average molecular weight of each elastomer shall fall within the above range.

The content of the thermoplastic styrene-based elastomer A in the thermoplastic elastomer composition is preferably from 10 to 50% by mass, and more preferably from 15 to 35% by mass.

Examples of the softener B include rubber softeners such as paraffin oil, naphthenic oil, and aromatic oil. Among these, among these, the affinity with the thermoplastic styrene elastomer is good, and bleeding hardly occurs. From the viewpoint, paraffin oil is preferred.

Kinematic viscosity at 40 ° C. of softening agent B is higher it is, to prevent volatilization during heating and melting, since the bleeding resistance even better, 30 mm ² / s or more, preferably 60 mm ² / s or more, more preferably 80 mm ² / s or more, from the viewpoint of improving the fusion property to the polar resin, more preferably 150 mm ² / s or more, since the lower one is easier to handle, 500 mm ² / s or less, preferably It is 450 mm ² / s or less, more preferably 400 mm ² / s or less, and from the viewpoint of improving abrasion resistance, more preferably 200 mm ² / s or less.

Regarding the content of the softening agent B, if the softening agent B is too small, the flexibility of the composition decreases, and the dispersibility of various components decreases. On the other hand, if the amount of the softener B is too large, oil bleed is likely to occur, and the fusion property to the polar resin decreases. From these viewpoints, the content of the softener B is at least 20 parts by mass, preferably at least 35 parts by mass, based on 100 parts by mass of the thermoplastic styrene-based elastomer A.
It is more preferably 50 parts by mass or more, 200 parts by mass or less, preferably 175 parts by mass or less, more preferably 150 parts by mass or less.

The content of the softener B in the thermoplastic elastomer composition is preferably 1 to 40% by mass.
, More preferably 5 to 35% by mass.

The thermoplastic polyester elastomer C preferably contains a hard segment (hard part) and a soft segment (soft part), and has an aromatic polyester block as a hard segment and an aliphatic polyether block as a soft segment. -More preferably, it is a polyether block copolymer.

Aromatic polyester block which is a hard segment of polyester-polyether block copolymer, phthalic acid, terephthalic acid, isophthalic acid, 1,4- or 2,6-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid,
One or more aromatic dicarboxylic acids such as 4,4'-diphenylsulfone dicarboxylic acid or alkyl esters thereof, and ethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, 1,4- Polycondensation with one or more diols such as cyclohexanediol, 1,4-cyclohexanedimethanol, 4,4'-dihydroxydibiphenyl, 2,2-bis (4'-β-hydroxyethoxydiphenyl) propane It is preferably a body. As commercially available products, for example, "Keyflex" (product name, manufactured by LG Chemical Co., Ltd.), "Perprene" (product name, manufactured by Toyobo Co., Ltd.), "Hytrel" (
Toray Dupont Co., Ltd., trade name), "Flekmer" (Nippon Synthetic Chemical Industry Co., Ltd.,
(Product name).

It is preferable that the aliphatic polyether block, which is a soft segment of the polyester-polyether block copolymer, mainly comprises a polyalkylene ether glycol.
The weight average molecular weight of the aliphatic polyether block which is a soft segment of the polyester-polyether block copolymer is preferably from 400 to 60,000. The weight average molecular weight of the aliphatic polyether block is determined by measuring the molecular weight in terms of polystyrene by gel permeation chromatography, as in the case of the thermoplastic styrene-based elastomer A, to determine the weight average molecular weight.

In the thermoplastic polyester elastomer C, it is more advantageous to have more soft segments in terms of fusibility, but it is preferable to have more hard segments in terms of abrasion. From such a viewpoint, the mass ratio of the hard segment to the soft segment (hard segment / soft segment) in the thermoplastic polyester elastomer C is 10/90 to 30/70, preferably 13/90.
/ 87 to 28/72, more preferably 15/85 to 25/75.

The A hardness of the thermoplastic polyester elastomer C is preferably 50 to 98, more preferably 60 to 95, and even more preferably 70 to 90. In the present invention, the A hardness is a durometer type A hardness.

As for the content of the thermoplastic polyester-based elastomer C, as the content of the thermoplastic polyester-based elastomer C increases, the phase-separated structure in which the thermoplastic polyester-based elastomer C is a continuous phase and the thermoplastic styrene-based elastomer A and the softener B are an island phase. And as a result, the fusion property with the polar resin is improved. Further, the smaller the amount of the thermoplastic polyester elastomer C, the better the flexibility. From these viewpoints, the content of the thermoplastic polyester-based elastomer C is 60 parts by mass or more, preferably 100 parts by mass or more, more preferably 100 parts by mass with respect to the total amount of the thermoplastic styrene-based elastomer A and the softener B of 100 parts by mass. Is at least 120 parts by mass, at most 300 parts by mass, preferably at most 200 parts by mass, more preferably at most 180 parts by mass. The content of the thermoplastic polyester elastomer C with respect to 100 parts by mass of the thermoplastic styrene-based elastomer A is preferably 100 parts by mass or more, more preferably 110 parts by mass or more, and still more preferably 150 parts by mass or more.
At least 200 parts by mass, more preferably at least 200 parts by mass, preferably at most 500 parts by mass, more preferably at most 450 parts by mass, still more preferably at most 350 parts by mass, still more preferably at most 300 parts by mass, even more preferably at most 250 parts by mass. Part or less.

Further, the content of the thermoplastic polyester elastomer C in the thermoplastic elastomer composition is preferably 40 to 85% by mass, and more preferably 55 to 75% by mass.

The total content of the thermoplastic styrene-based elastomer A, the softener B, and the thermoplastic polyester-based elastomer C is preferably 75% by mass or more, more preferably 80% by mass or more, and further preferably 90% by mass in the thermoplastic elastomer composition. % Or more.

The thermoplastic elastomer composition of the present invention may further contain a compatibilizer D, a polyolefin E or the like. These may be used alone or in combination.

  By blending the compatibilizer D, the fusion property with the polar resin is improved.

The compatibilizing agent D is composed of an acid-modified hydrogenated thermoplastic styrene-based elastomer D1, an acid-modified olefin-based thermoplastic elastomer D2, and a graft polymer D3 of a styrene-based elastomer and a urethane-based elastomer because of being excellent in the effect of improving the fusibility. At least one elastomer selected from the group is preferred.

Examples of the acid-modified hydrogenated thermoplastic styrene-based elastomer D1 include a block unit of a polymer composed of a styrene-based monomer (s2) and a block unit of a polymer composed of a conjugated diene compound (b2).
The hydrogenated product of the block copolymer (Z2) consisting of the following is preferably acid-modified.

Styrene monomers constituting the block unit (s2) include styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, And vinyl anthracene.

The conjugated diene compound constituting the block unit (b2) includes butadiene, isoprene,
1,3-pentadiene and the like.

The block copolymer (Z2) is composed of a hard part (hard segment) composed of block units (s2) and a soft part (soft segment) composed of block units (b2). From the viewpoint of determining the overall physical properties, The content of the styrene monomer unit in the block copolymer (Z2) is preferably from 5 to 70% by mass, more preferably from 10 to 60% by mass, and still more preferably from 20 to 70% by mass.
5050% by mass.

The hydrogenation of the block copolymer (Z2) may be part or all, but the hydrogenation reduces unsaturated bonds and provides heat resistance, weather resistance and mechanical properties. Can be From these viewpoints, the hydrogenation rate is preferably 80% or more, and more preferably 90% or more.

Specific examples of the hydrogenated product of the block copolymer (Z2) include styrene-ethylene-butylene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer, and styrene-ethylene-ethylene-propylene-styrene. Block copolymer, styrene-ethylene / butylene (styrene control distribution) -styrene block copolymer, styrene-isobutylene-styrene block copolymer, styrene-butadiene rubber, acrylonitrile-butadiene rubber, pyridine-butadiene rubber, styrene-isoprene Rubber, styrene-ethylene copolymer, styrene-butadiene-styrene block copolymer, styrene-
Isoprene-styrene block copolymer, poly (α-methylstyrene) -polybutadiene-
Examples thereof include poly (α-methylstyrene), poly (α-methylstyrene) -polyisoprene-poly (α-methylstyrene), an ethylene-propylene copolymer, and styrene-chloroprene rubber. These may be used alone or as a mixture of two or more, but from the viewpoint of raw material preparation and workability, styrene-ethylene / butylene-styrene block copolymer (SEBS)
Styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene block copolymer (SEEPS), styrene-ethylene-butylene (styrene control distribution) -styrene block copolymer ( It is preferably at least one selected from the group consisting of SEB (S) S) and styrene-isobutylene-styrene block copolymer (SIBS).

The acid modification of the hydrogenated product of the block copolymer (Z2) is not particularly limited, but can be performed, for example, by introducing a carboxyl group or an acid anhydride group into the hydrogenated product. The introduction of the carboxyl group or acid anhydride group can be carried out according to a method known per se. Specifically, for example, hydrogenated products and unsaturated monocarboxylic acids exemplified by acrylic acid, methacrylic acid and the like; unsaturated dicarboxylic acids exemplified by maleic acid, fumaric acid, hymic acid, itaconic acid and the like; Maleic acid, hymic anhydride, an anhydride of unsaturated dicarboxylic acid exemplified by itaconic anhydride, and the like, in the presence of an organic peroxide, in the presence or absence of a solvent, and subjected to a graft reaction Can be obtained. It can also be obtained commercially.

The acid-modified amount of the acid-modified hydrogenated thermoplastic styrene-based elastomer D1 is preferably 0.1 to 10% by mass, more preferably 0.3 to 5.0% by mass, and still more preferably 0 to 10% by mass, from the viewpoint of compatibility and workability.
0.5 to 3.0% by mass.

The weight-average molecular weight of the acid-modified hydrogenated thermoplastic styrene-based elastomer D1 is preferably 50,000 or more from the viewpoint of heat resistance, and is preferably 400,000 or less from the viewpoint of fluidity of the melt and rubber elasticity. From these viewpoints, the weight-average molecular weight of the acid-modified hydrogenated thermoplastic styrene-based elastomer D1 is preferably 50,000 to 400,000. As the acid-modified hydrogenated thermoplastic styrene-based elastomer D1, only one type may be used, or two or more types having different weight average molecular weights, 1,2-vinyl bond amounts, etc. may be used in combination. When two or more kinds are used in combination, the weighted average value thereof is preferably within the above range, and more preferably each is within the above range.

The A hardness of the acid-modified hydrogenated thermoplastic styrene-based elastomer D1 is preferably 30 to 97, more preferably 50 to 93, and even more preferably 70 to 90.

Examples of the acid-modified olefin-based thermoplastic elastomer D2 include α-olefin copolymer elastomers such as ethylene-propylene copolymer, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, and 1-octene; Copolymerized elastomers with conjugated dienes, mixtures of two or more of these, and the like, are mentioned, and at least some of these are acid-modified. Among these, acid-modified ethylene-α-olefin copolymer and propylene-
Acid-modified α-olefin copolymers are preferred.

The acid-modified treatment can be performed in the same manner as in the acid-modified hydrogenated thermoplastic styrene-based elastomer D1.

The acid-modified amount of the acid-modified olefin-based thermoplastic elastomer D2 is preferably from 0.1 to 10% by mass, more preferably from 0.3 to 5.0% by mass, from the viewpoint of compatibility and workability.

The A hardness of the acid-modified olefin-based thermoplastic elastomer D2 is preferably 95 or less, more preferably 10 to 90, and still more preferably 20 to 90.

As the graft polymer D3 of a styrene-based elastomer and a urethane-based elastomer,
Even with a diblock copolymer having one styrene-based elastomer block and one polyurethane elastomer block, a polyblock copolymer in which a total of three or four or more styrene-based elastomers and polyurethane elastomer blocks are bonded. A diblock copolymer in which one styrene-based elastomer and one polyurethane elastomer block are bonded is preferable from the viewpoint of excellent heat resistance and not releasing a bad smell when melted by heating. Commercial products include Kuramylon (registered trademark) TU polymer manufactured by Kuraray Co., Ltd.

When the compatibilizing agent D is too large, phase separation is difficult to be formed. Therefore, when the compatibilizing agent D is used, from the viewpoint of improving the fusibility without impairing the phase separation structure, the thermoplastic styrene-based elastomer A 100% Parts by weight, preferably 1 to 30 parts by weight, more preferably 5 to 20 parts by weight.

Further, the content of the compatibilizer D in the thermoplastic elastomer composition is preferably 0.5 to 20% by mass, and more preferably 1 to 5% by mass.

  Polyolefin E may be included from the viewpoint of moldability.

Examples of the polyolefin E include polyethylene, polypropylene, and ethylene-propylene copolymer.

The content of the polyolefin E is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, more preferably 40 parts by mass or less, based on 100 parts by mass of the thermoplastic styrene-based elastomer A because a smaller amount can maintain flexibility. 30 parts by mass or less.

The thermoplastic elastomer composition of the present invention may further contain a thickener. By blending the thickener, after melt molding of the thermoplastic elastomer composition, the stiffness of the resin is improved during cooling in the mold, so that the molded article can be taken out of the mold even in a short cooling time. Thus, the molding cycle time can be shortened.

As the thickener, any one can be used as long as it has the effect of increasing the melt tension during the molding of the thermoplastic resin. Among them, epoxy thickeners, acrylic thickeners and the like can be used. preferable.

As the epoxy-based thickener, an epoxy compound which is a polymer having a styrene structure in the skeleton is preferable.

Commercially available epoxy compounds include Alphon UG series manufactured by Toagosei Co., Ltd.
Co., Ltd.'s Marproof G series and BASF's John Krill ADR series.

As the acrylic thickener, an acrylic polymer processing aid, acryl-modified polytetrafluoroethylene, and the like are known. In the present invention, acryl-modified polytetrafluoroethylene is preferable. Acrylic-modified polytetrafluoroethylene is a thermoplastic resin because polytetrafluoroethylene, whose compatibility with a thermoplastic resin has been improved by acrylic modification, turns into fibrils by melt-kneading to form a fibrous network. The moldability can be improved by increasing the melt viscosity of the resin composition.

When a thickener is included, the content of the thickener in the thermoplastic elastomer composition is preferably 1
-30% by mass, more preferably 2-20% by mass.

The composition of the present invention may contain another thermoplastic resin or a thermoplastic elastomer as long as the effects of the present invention are not impaired. Among them, the polar elastomer is taken into the thermoplastic polyester elastomer C which is a continuous phase, and can improve the flexibility and the fusibility of the whole composition. The polar elastomer is not particularly limited, and examples thereof include NBR (nitrile rubber), polyurethane rubber, epichlorohydrin rubber, polyurethane thermoplastic elastomer, and polyamide thermoplastic elastomer.

The thermoplastic elastomer composition of the present invention is, if necessary, a reinforcing agent such as carbon black, silica, carbon fiber, or glass fiber, an inorganic filler, or an insulating heat conductive filler, as long as the effects of the present invention are not impaired. , Pigments, hydrated metal compounds, flame retardants such as red phosphorus, ammonium polyphosphate, antimony, silicone, etc., antistatic agents, tackifiers, crosslinking agents, crosslinking aids, heat stabilizers, antioxidants, light stabilizers, It may contain various additives such as an ultraviolet absorber, an antiblocking agent, a sealability improving agent, a release agent, a colorant, and a fragrance.

The thermoplastic elastomer composition of the present invention is obtained by mixing a raw material containing a thermoplastic styrene-based elastomer A, a softening agent B, a thermoplastic polyester-based elastomer C, and further, if necessary, a compatibilizer D, a polyolefin E, and the like. Obtained by solidification.

The term “mixing” as used in the present invention is not particularly limited as long as various components are satisfactorily mixed, and various components may be dissolved and mixed in a dissolvable organic solvent, or may be melt-kneaded. Although the raw materials may be mixed, the mixing of the raw materials is preferably performed under conditions where the thermoplastic polyester elastomer C is melted.

The conditions under which the thermoplastic polyester-based elastomer C melts can be defined, for example, based on the melting point of the thermoplastic polyester-based elastomer C that can be determined by viscoelasticity measurement. Although it is a condition, the melting and kneading method is not necessarily the melting point measured in a static state, it may be melted at a temperature lower than the melting point, and the higher the temperature, the lower the melt viscosity and the easier it is to mix, but it is not so much If it is high, thermal decomposition may occur. From these viewpoints, the preferred melting temperature range when kneading is involved is -30 ° C to +
The temperature is 100 ° C, more preferably -20 ° C to + 50 ° C with respect to the melting point.

In the case of melt-kneading, a general extruder can be used, and in order to improve the kneading state,
It is preferred to use a twin screw extruder. For the supply to the extruder, one obtained by mixing various components in advance using a mixing device such as a Henschel mixer may be supplied from one hopper, or each component is charged into two hoppers and quantitatively determined by a screw or the like below the hopper. You may serve while doing.

The product obtained by mixing the raw materials constituting the thermoplastic elastomer composition can be in the form of a pellet, powder, sheet, or the like, depending on the application. For example, the mixture is melt-kneaded by an extruder, extruded into a strand, and cut into a columnar or rice-grained pellet by a cutter while being cooled in cold water. The obtained pellet is usually formed into a predetermined sheet-like molded product or a molded product by injection molding or extrusion molding. Further, the melt-kneaded material can be formed into pellets with a ruder or the like and used as a raw material for forming. An intermediate product obtained by attaching a mount or the like to the sheet-like thermoplastic elastomer composition may be used.

The A hardness of the thermoplastic elastomer composition of the present invention is preferably 70 or less, more preferably 65 or less, and further preferably 60 or less, from the viewpoint of flexibility. Also, preferably 20 or more,
It is more preferably at least 25, even more preferably at least 30.

A molded article is obtained by appropriately subjecting the thermoplastic elastomer composition of the present invention to heat molding according to a conventional method. The use of the molded article obtained by heat-molding the thermoplastic elastomer composition of the present invention is not particularly limited, and general styrene-based elastomers, polyolefin-based elastomers, polyurethane-based elastomers, polyamide-based elastomers, and acrylic-based elastomers And polyester-based elastomers.

As an apparatus used for producing a molded article using the thermoplastic elastomer composition of the present invention, any molding machine capable of melting a molding material can be used. For example, kneaders, extruders,
Examples include an injection molding machine, a press molding machine, a blow molding machine, and a mixing roll.

The thermoplastic elastomer composition of the present invention can be used as a composite molding material,
Since it is fused to various materials, it can be suitably used for bonding members made of different materials. For example, it is used for fusing to at least one member selected from the group consisting of metal, ceramic, glass, and polar resin, and exhibits particularly good adhesion to polar resins and the like.

The metal is not particularly limited, and includes, for example, aluminum, aluminum alloy, stainless steel, iron, copper, galvanized steel, magnesium, magnesium alloy, and various plating products.

Examples of the polar resin include polycarbonate, polyester resin, poly (meth) acrylate resin such as polymethyl methacrylate, polyethylene oxide resin, polypropylene oxide resin, polyvinyl acetate resin, polyamide resin, and polyurethane resin. Polystyrene resin such as ABS resin, polyvinyl ether resin, polyvinyl alcohol resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin, polyetherimide resin, polyetherketone resin, polyetheretherketone resin, LCP (liquid crystal polymer ), Polar resins such as ionomers, and mixtures of two or more thereof.

When the thermoplastic elastomer composition of the present invention is fused to a polar resin, the peel strength from the polar resin is preferably 120 N / 25 mm or more from the viewpoint of adhesive properties.

In the present invention, the fusion is performed by applying heat equal to or higher than the melting point of the thermoplastic elastomer composition of the present invention, forming a melt, and then solidifying at a temperature equal to or lower than the melting point, thereby fixing to the interface of the fusion target. A phenomenon. To apply heat, a heat press, a heating roll, a hot air generator, heated steam, an ultrasonic welder, a high-frequency welder, a laser, or the like can be used. Therefore, even if the interface of the fused portion has a complicated three-dimensional shape, it can be formed into a complicated three-dimensional shape, and can be formed and integrated.

Therefore, the thermoplastic elastomer composition of the present invention can be integrated with a member to form a composite molded article. This makes it possible to combine a member having a complicated joint surface or a member having joint surfaces having different shapes from each other.

The composite molded article obtained by fusing the thermoplastic elastomer composition of the present invention to a member is injection molding, injection compression molding, insert molding, multicolor molding, vacuum molding, pressure molding, blow molding, hot press molding, foam molding, laser Fusion molding, extrusion molding, etc., can be obtained by molding, but the thermoplastic elastomer composition of the present invention is not self-adhesive like an adhesive, and is easy to handle. Therefore, it can be applied to injection molding.

As the composite molded article in which the thermoplastic elastomer composition of the present invention is fused to a member, an insert molded article in which a polar resin is inserted into a molded article made of the thermoplastic elastomer composition, a thermoplastic elastomer composition, and a polar resin And the like, and a composite molded article obtained by multicolor molding of the above.

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples. Various physical properties of the raw materials used in Examples and Comparative Examples were measured by the following methods.

<Component A (thermoplastic styrene elastomer) and component A ′>
(Styrene monomer unit content)
The content of styrene and / or a styrene derivative is determined by performing proton NMR measurement with a nuclear magnetic resonance apparatus (DPX-400, manufactured by BRUKER, Germany) and quantifying the characteristic groups of styrene.

[Weight average molecular weight (Mw)]
Under the following measurement conditions, the molecular weight is measured in terms of polystyrene by gel permeation chromatography, and the weight average molecular weight is determined.

Measuring device / pump: JASCO (JASCO Corporation), PU-980
・ Column oven: AO-50, manufactured by Showa Denko KK
・ Detector: Hitachi, RI (differential refractometer) detector L-3300
・ Column type: Showa Denko K-805L (8.0 × 300mm) and K-804L (8.0 × 300mm)
)] Use one each in series. Column temperature: 40 ℃
・ Guard column: KG (4.6 × 10mm)
・ Eluent: chloroform ・ Eluent flow rate: 1.0 ml / min
・ Sample concentration: about 1mg / ml
・ Sample solution filtration: 0.45μm pore size disposable filter made of polytetrafluoroethylene ・ Standard sample for calibration curve: Polystyrene manufactured by Showa Denko KK

<Component B (softener) and component B ′>
(Kinematic viscosity)
Measure at a temperature of 40 ° C according to JIS Z 8803.

<Component C (thermoplastic polyester elastomer) and component C ′>
[Hard segment / Soft segment (mass ratio)]
The mass ratio of the hard segment to the soft segment was determined using a nuclear magnetic resonance apparatus (manufactured by BRUKER, Germany, DPX-400) at a concentration of 3 to 5 vol% in deuterated chloroform at 25 ° C. using proton NMR.
The measurement is performed, and it is calculated from the signal intensity ratio of the methylene peak adjacent to various oxygens in the molecular structure.

[A hardness]
Measure with JIS K 6253 type A.

(Melting point)
Using a differential scanning calorimeter (DSC) device, 10 ° C / mi according to the method specified in JIS K 7121
The temperature of the melting peak obtained by raising the temperature at n is defined as the melting point. If multiple melting peaks appear,
The melting peak that appears at a lower temperature is the melting point.

<Component D (Compatibilizer) and Component D ′>
(Styrene monomer unit content)
The content of styrene and / or a styrene derivative is determined by performing proton NMR measurement with a nuclear magnetic resonance apparatus (DPX-400, manufactured by BRUKER, Germany) and quantifying the characteristic groups of styrene.

[Weight average molecular weight (Mw)]
Under the following measurement conditions, the molecular weight is measured in terms of polystyrene by gel permeation chromatography, and the weight average molecular weight is determined.

Measuring device / pump: JASCO (JASCO Corporation), PU-980
・ Column oven: AO-50, manufactured by Showa Denko KK
・ Detector: Hitachi, RI (differential refractometer) detector L-3300
・ Column type: Showa Denko K-805L (8.0 × 300mm) and K-804L (8.0 × 300mm)
)] Use one each in series. Column temperature: 40 ℃
・ Guard column: KG (4.6 × 10mm)
・ Eluent: chloroform ・ Eluent flow rate: 1.0 ml / min ・ Sample concentration: about 1 mg / ml
・ Sample solution filtration: 0.45μm pore size disposable filter made of polytetrafluoroethylene ・ Standard sample for calibration curve: Polystyrene manufactured by Showa Denko KK

[A hardness]
It is measured according to the method specified in JIS K 6253.

(Acid modification amount)
Press the blend of base material and organic acid before denaturation using a 0.1 mm spacer.
R was measured, and a calibration curve was created from the characteristic absorption amount of carbonyl (1600-1900 cm ^-1 ) and the charged amount of organic acid, and IR measurement of an acid-modified press plate (IR measuring instrument: FT manufactured by Horiba, Ltd.) -210) to determine the amount of modification (acid content).

Examples 1 to 12 and Comparative Examples 1 to 6
(1) Preparation of thermoplastic elastomer composition (pellet) The materials shown in Tables 5 to 7 other than paraffin oil were dry-blended and impregnated with paraffin oil to prepare a mixture. Thereafter, the mixture was melt-kneaded with an extruder under the following conditions, extruded into strands, and cooled in cold water by a cutter, with a diameter of about 3 mm and a thickness of 3 mm.
It was cut to about mm to produce pellets of the thermoplastic elastomer composition.

(Melting and kneading conditions)
Extruder: KZW32TW-60MG-NH (trade name, manufactured by Technovel Corporation)
Cylinder temperature: 180 ~ 220 ℃
Screw rotation speed: 300r / min

  The details of the raw materials described in Tables 5 to 7 used in Examples and Comparative Examples are as follows.

(2) Preparation of Molded Article of Thermoplastic Elastomer Composition Pellets were injection-molded under the following conditions to prepare a plate having a thickness of 2 mm, a width of 125 mm and a length of 125 mm.

[Injection molding conditions]
Injection molding machine: 100MSIII-10E (trade name, manufactured by Mitsubishi Heavy Industries, Ltd.)
Injection molding temperature: 200 ℃
Injection pressure: 30%
Injection time: 3sec
Mold temperature: 40 ℃

The following evaluation was performed about the composition obtained by the Example and the comparative example. Table 5 shows the results.
7 are shown.

[Flexibility]
Durometer A hardness was measured using a plate (125 mm square plate) one day after injection molding in accordance with the method specified in JIS K 6253. A hardness is preferably 70 or less.

(Heat fusion)
Insert the following polar resin into a mold with a thickness of 4 mm × width 25 mm × length 125 mm, under the following conditions,
The thermoplastic elastomer compositions obtained in Examples and Comparative Examples were injection-molded to prepare strip-shaped fusion test pieces.

<Insert material (polar resin)>
(1) Size: 2mm thick x 25mm wide x 120mm long
(2) Type: PC (polycarbonate): manufactured by Mitsubishi Engineering Plastics, Iupilon H-3000

<Injection molding conditions>
Injection molding machine: 100MSIII-10E, manufactured by Mitsubishi Heavy Industries, Ltd.
Injection molding temperature: 240 ° C
Injection pressure: 98MPa, injection speed: 50%, holding pressure: 20%, holding time: 10sec
Injection time: 2sec
Mold temperature: 40 ℃

Using the obtained fusion-bonded test piece, a tensile test was performed on the thermoplastic elastomer layer and the polar resin layer at an ambient temperature of 23 ° C in a direction of 180 ° at 50 mm / min, and the peel strength between the skin material layer and the base material layer (unit) : N / 25mm
) Was measured. The peel strength is preferably 120 N / 25 mm or more.

[Abrasion resistance (Taber abrasion test)]
Using an injection-molded plate (125 mm square plate), conforming to JIS K 7204, 23 ° C, wear wheel: H-22, rotation speed: 72 r / min, number of rotations: 1000 times, load: 1000 g, wear loss (1000 g) mg). The amount of wear loss is preferably 300 mg or less.

(Surface stickiness)
After the injection molded plate (125 mm square plate) was allowed to stand at an ambient temperature of 23 ° C. for 24 hours, the surface was visually observed and touched with a finger, and the surface stickiness was evaluated according to the following evaluation criteria.
<Evaluation criteria>
：: There is no wet gloss visually, and the surface is smooth and the finger slips well.
：: There is no wet gloss visually, and sticking does not occur when touched with a finger, but slippage is not good.
Δ: There is no wet gloss visually, but there is a tack that sticks when touched with a finger.
×: The surface has wet gloss and has a tack that sticks when touched with a finger.

(Phase separation structure)
The cut surface cut to 10 mm from the end in the cross-sectional direction of the injection-molded plate (125 mm square plate) was flattened with a microtome by 0.1 mm, and the cut surface was dyed with a ruthenium salt solution for 1 hour. The cross-section was photographed with a scanning electron microscope (Hitachi High-Technologies S4800) to confirm the phase separation structure, and it was determined whether the structure was "sea island", "co-continuous", or "sea island / co-continuous". . In addition, “sea-island / co-continuous” indicates that a sea-island structure as a whole but a co-continuous phase in which continuity of the dispersed phase is observed partially exists.

Electron micrographs of Example 4 and Comparative Example 1 are shown in FIGS. The black portion is a dispersed phase composed of the thermoplastic styrene-based elastomer A and the softener B. In Example 4 (FIG. 1), a sea-island structure having the thermoplastic polyester-based elastomer C as a continuous phase is formed. On the other hand, in Comparative Example 1 (FIG. 2), the phase composed of the thermoplastic styrene-based elastomer A and the softener B is a continuous phase, and forms a co-continuous structure with the continuous phase of the thermoplastic polyester-based elastomer C. ing.

From the above results, the thermoplastic elastomer compositions of Examples are excellent in flexibility, fusion property to polar resins, and abrasion resistance, hardly cause surface stickiness, and are useful as molding materials by injection molding. You can see that there is.
In contrast, Comparative Example 1 in which the weight average molecular weight of the thermoplastic styrene-based elastomer was too small
In 2, the bicontinuous structure is seen at least in part and lacks in the fusion property to the polar resin.
The Taber abrasion value is large and the abrasion resistance is poor. In addition, injection molded plate
Visual observation of the surface after standing at 23 ° C. for 24 hours showed no wet luster, but there was a tack like sticking and lifting the plate when touched with a finger.
Comparative Example 3 in which the amount of the softening agent was too small had insufficient flexibility and was inferior in tactile sensation.
Comparative Example 4 in which the amount of the softener was too large had a co-continuous structure, lacked in the fusion property to the polar resin and the abrasion resistance, and had a wet gloss that could be visually recognized on the injection molded plate. There is a tack that sticks when touched with a finger, and the surface is sticky.
Comparative Example 5, in which the amount of the thermoplastic polyester elastomer was too small, had a bicontinuous structure, inadequate fusibility to polar resin, poor abrasion resistance, and an injection molded plate. Has a tack when touched with a finger. Comparative Example 6, in which the amount of the thermoplastic polyester-based elastomer was too large, lacks flexibility and has a poor touch feeling.

The thermoplastic elastomer composition of the present invention is useful for various molded articles such as automobiles, electronic materials, home appliances, electric appliances, medical tools, packaging materials, stationery and miscellaneous goods, and further grips, tubes, packing, gaskets, Used for various members such as cushions, films, sheets and the like.

Examples 1 to 12 and Comparative Examples 1 to 6 (Example 9 is a reference example)
(1) Preparation of thermoplastic elastomer composition (pellet) The materials shown in Tables 5 to 7 other than paraffin oil were dry-blended and impregnated with paraffin oil to prepare a mixture. Thereafter, the mixture is melt-kneaded with an extruder under the following conditions, extruded into strands, and cut into a diameter of about 3 mm and a thickness of about 3 mm by a cutter while cooling in cold water, and pellets of the thermoplastic elastomer composition are formed. Manufactured.

Claims (5)

Comprising a thermoplastic styrene-based elastomer A, a softener B, and a thermoplastic polyester-based elastomer C,
The thermoplastic styrene-based elastomer A has a styrene-based monomer unit content of 10 to 50% by mass, and a weight average molecular weight of 200,000 to 500,000,
The kinematic viscosity at 40 ° C. of the softener B is 30 to 500 mm ² / s,
The thermoplastic polyester elastomer C contains a hard segment and a soft segment in a mass ratio of 10/90 to 30/70 (hard segment / soft segment),
With respect to 100 parts by mass of the thermoplastic styrene-based elastomer A, 20 to 200 parts by mass of the softening agent B, and with respect to 100 parts by mass of the total amount of the thermoplastic styrene-based elastomer A and the softening agent B, A thermoplastic elastomer composition containing 60 to 300 parts by mass of a polyester elastomer C. The thermoplastic styrene elastomer A according to claim 1, wherein the thermoplastic styrene elastomer A has a phase separation structure in which a continuous phase composed of the thermoplastic polyester elastomer C has a dispersed phase composed of the thermoplastic styrene elastomer A and the softener B. Elastomer composition.   The thermoplastic elastomer composition according to claim 1 or 2, having an A hardness of 70 or less. Further, the compatibilizer D was added to 100 parts by mass of the thermoplastic styrene-based elastomer A, from 1 to
The thermoplastic elastomer composition according to any one of claims 1 to 3, comprising 30 parts by mass. The thermoplastic elastomer composition according to any one of claims 1 to 4, which is fused to a polar resin,
Composite molded body.