WO2000047685A1 - Adhesive composition and method of bonding fibrous material with the same - Google Patents

Abstract

An adhesive composition which comprises an ethylene/propylene/unconjugated diene terpolymer rubber latex having an unconjugated diene unit content of 3 to 15 wt. % and an aqueous resorcinol/formaldehyde resin solution. The composition is utilizable in internally bonding a fibrous material to a matrix comprising an ethylene/propylene/unconjugated diene terpolymer rubber or in externally bonding a fibrous material to an external object (e.g., a rubber sheet) comprising an ethylene/propylene/unconjugated diene terpolymer rubber. An improved adhesion strength is attained by infiltrating the adhesive composition into the fibrous material and fixing the composition thereto before the bonding operation.

Description

 TECHNICAL FIELD The present invention relates to an adhesive composition and a method for bonding a fiber material using the same.

 The present invention relates to an adhesive composition and a method for bonding a fiber material using the same, and more particularly, to bonding a fiber material into a matrix containing an ethylene-propylene-non-conjugated gen terpolymer rubber. The present invention relates to an adhesive composition suitable for adhering a fibrous material to an external object containing ethylene-propylene-non-conjugated gen terpolymer rubber, and an adhesive method using the same.冃

 Ethylene-propylene-non-conjugated gen terpolymer rubber (hereinafter abbreviated as EPDM rubber) has excellent heat resistance, weather resistance and ozone resistance, and is mainly used for heat-resistant belts for automobiles and various heat-resistant hoses It is used. Usually, the EPDM rubber used for these is often reinforced with a fiber material. In order to reinforce EPDM rubber with a fiber material, adhesion between the EPDM rubber and the fiber material is important. However, EPDM rubber is inferior in adhesiveness to fiber materials, and its use is limited.

 Generally, an adhesive composition called a so-called RFL adhesive is used to improve the adhesiveness between a fiber material and a rubber material such as a natural rubber-styrene-butadiene copolymer. , Rubber latex and resorcinol-formaldehyde resin aqueous solution and rubber latex, natural rubber latex, styrene butadiene copolymer latex, styrene-butadiene-vinylidine terpolymer latex Etc. are used:

However, when the RFL adhesive is used for bonding between EPDM rubber and a fiber material, EPD VI rubber has a chemical structure with few double bonds and lacks reactivity, so it is difficult to react with the fiber material. Insufficient bond strength can be achieved: Therefore, an adhesive or bonding method that can more strongly adhere fiber materials to EPD VI rubber is desired. ing.

 As an adhesive proposed from such a viewpoint, for example, there is an adhesive composition of a resorcinol-formaldehyde resin aqueous solution and a chlorosulfonated polyethylene latex (JP-A-57-105476). Gazette). However, this adhesive composition suffers from problems such as a decrease in adhesive strength when heat-treated at a high temperature of 20 (TC or more) and a decrease in strength depending on the type of fiber due to the acid gas decomposed by chlorosulfonated polyethylene. There is.

 Also, an adhesive composition of butadiene rubber latex and a special chlorophenol compound has been proposed (Japanese Patent Application Laid-Open No. Hei 7-224267), but it cannot be said that the adhesive strength to fibers is sufficient. Disclosure of the invention

 An object of the present invention is to provide an industrially advantageous adhesive composition which can eliminate or reduce the above-mentioned problems in bonding a fiber material to an EPDM rubber. It is another object of the present invention to provide a method for bonding a fiber material to an EPDM rubber using such an adhesive composition.

 The present inventors have conducted intensive studies to achieve the above object, and as a result, have found that ethylene-butene-pyrene-non-conjugated gen terpolymer rubber latex (abbreviated as "EPD ラ Rubber latet tas") having a specific composition and resorcin-formaldehyde It has been found that an adhesive composition comprising an aqueous resin solution (abbreviated as "RF resin aqueous solution") can firmly bond the EPDM rubber and the fiber material, and completed the present invention.

 That is, according to the present invention, there is provided an adhesive composition comprising a ΡDM rubber latex containing 3 to 15% by weight of a non-conjugated gen component and an RF resin aqueous liquid. On the other hand, there are two modes for bonding a fiber material using such an adhesive composition. In the first mode, a fiber material is internally bonded to a matrix containing EPDM rubber. In a second embodiment, the fibrous material is externally bonded to an external object including EPD.M rubber:

More specifically, according to the first aspect, there is provided a method of bonding a fiber material to a matrix containing EPDM rubber, wherein the fiber material is contained in the matrix. Prior to bonding, a preliminary step of impregnating and fixing the fiber material in advance with an adhesive composition containing an EPDM rubber latex containing 3 to 15% by weight of a non-conjugated diene component and an aqueous RF resin solution; Material bonding method is provided

Further, according to the second aspect, there is provided a method for bonding a fiber material to an external object including EPDM rubber, wherein the non-conjugated gen component is bonded to the external object before the fiber material is bonded to the external object. 3 to 1 5 weight _^0/0 impregnating an adhesive composition comprising an a RF榭脂aqueous liquid EPDM rubber latex containing in advance in the fibrous material, including preliminary steps for fixing, provides adhesion method of the fiber material Is done.

Rubber component of the EPDM rubber in the latex, ethylene, terpolymers of Buropiren and Hitomo officers Zhen, usually ethylene 4 0-8 0 weight _^0/0, propylene 1 5-6 0 weight. /. A copolymer having a composition of 15% by weight or less is used as the non-conjugated diene. Examples of the non-conjugated diene include dicyclopentadiene, ethylidene norbornene, and 1,4-hexadiene.

As the EPDM rubber latex, a non-conjugated diene component 3 to 1 5 weight ⁰ /. , Preferably a 5 to 1 5 weight _^0/0 containing EPDM rubber particles, 2 0-7 0 weight _^0/0 degree water containing dispersion with solids is preferred. If the non-conjugated gen component is less than 3% by weight, the co-vulcanizability of the matrix or the external object EPDM rubber and the EPDM rubber in the adhesive composition impregnated into the fiber material is low, so that the desired adhesive strength is obtained. Is not obtained .:

 The EPDM rubber latex is prepared, for example, by mixing and stirring a solution of EPDM rubber in an organic solvent and an aqueous solution containing an appropriate emulsifier to disperse the EPDM rubber solution in water, and then heating the organic solvent under reduced pressure. Then, if necessary, a part of the water is concentrated by heat concentration, membrane or centrifugation, and the solid content is 20 to 70% by weight. /. It can be prepared by increasing the concentration to about the same level. However, the method for preparing the EPDM rubber latex is not particularly limited.

 Specific examples of the organic solvent include aliphatic hydrocarbons such as hentane, hexane, and cyclohexane, alicyclic hydrocarbons, aromatic hydrocarbons such as toluene, xylene, and ethylbenzene, and chlorinated hydrocarbons. These can be used alone or in combination of two or more.

Examples of the emulsifier include anion emulsifier, nonionic emulsifier, cationic emulsifier And amphoteric emulsifiers. Specific examples of the anion emulsifier include fatty acid salts, rosin acid salts, alkyl sulfate salts, alkylbenzene sulfonates, alkane sulfonates, alkyl sulfosuccinates, alkyl phosphate salts, polyoxyethylene alkyl sulfate salts. Specific examples of nonionic emulsifiers include boroxyethylene alkyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene alkyl phenyl ethers, and sucrose. Fatty acid esters, polyglycerin fatty acid esters, and the like. Specific examples of the cationic emulsifier include quaternary ammonium halide, alkylpyridinium halide, and the like. Specific examples of the amphoteric emulsifier include N-alkyl-N, N-dimethylammonium betaine. Among these emulsifiers, anionic emulsifiers are preferably used from the viewpoint of adhesive strength.

 The amount of the emulsifier is usually about 0.1 to 15% by weight based on the EPDM rubber in the adhesive composition. If it is less than 0.1% by weight, the emulsion stability effect is not sufficient. Conversely, if it exceeds 15% by weight, not only is it not economical, but it also impairs the adhesiveness of the resulting adhesive composition:

 Further, isopropropyl alcohol, which is soluble in both water and organic solvents, may be used in combination as an emulsifying aid.

 The RF resin aqueous liquid can be obtained by reacting formaldehyde with resorcinol in a known manner, for example, in the presence of an alkali metal hydroxide. Specifically, 1 mol of resorcinol and 0 mol of formaldehyde It is obtained by reacting 5 to 4 moles in an aqueous solution of an alkali metal hydroxide. The resin concentration of the obtained aqueous solution of RF resin is generally about 5 to 40% by weight. Alternatively, a similar aqueous RF resin solution can be prepared by reacting a substance that easily forms formaldehyde (eg, paraformaldehyde) with resorcin in an aqueous solution:

In the adhesive composition of the present invention, the mixing ratio of the EPDM rubber latetus and the RF resin aqueous liquid is such that the mixing ratio of the EPDM rubber solids in the EPD.VI rubber latex is 100 parts by weight of the RF resin solids in the RF resin aqueous liquid. E is mixed so as to be 100 to 2000 parts by weight, preferably 100 to 150 parts by weight, particularly 100 () to 100 parts by weight. If the ratio of the solid content of the EPDM rubber in the PDM rubber latex is less than 100 parts by weight, sufficient adhesive strength cannot be obtained. Conversely, if the EPDM rubber solids content is more than 2000 parts by weight, the corresponding effect cannot be obtained and it is not economical. In addition, various additives such as a viscosity modifier, an antioxidant, zinc oxide, and a magnesium compound may be added to the adhesive composition of the present invention as needed. Further, the adhesive composition of the present invention may contain an adhesion aid such as a vulcanization accelerator, a blocked isocyanate, a black phenol formalin condensate, or an epoxy compound. Further, the adhesive composition of the present invention can be used in combination with a latex such as a styrene-butadiene copolymer latex or a styrene-butadiene-vinylpyridine terpolymer latex.

 The fiber material bonded using the adhesive composition of the present invention is not particularly limited, and examples thereof include vinylon, nylon, polyester, aromatic polyamide, rayon, and glass fiber. In addition, the form of the fiber material can be appropriately selected according to the intended use, such as cord, canvas, short fibers for reinforcement, and short fibers for flocking. Further, the form of the EPDM rubber to be bonded to the fiber material is not limited, and may be a rubber matrix in which reinforcing short fibers are contained, or a rubber sheet to be bonded to a cloth as a fiber material. can do. However, depending on the form of the fiber material and the form of the EPDM rubber to be bonded thereto, either the first embodiment or the second embodiment of the bonding method of the present invention is employed.

In the bonding method of the present invention, in order to impregnate and fix the adhesive composition to the fiber material, the adhesive composition is impregnated into the fiber material by an appropriate method such as dipping, brushing, spraying, and roll coating. , dried at a suitable temperature for 2 7 0 ° C from room temperature, it is only necessary to fix the fiber materials and heat-treated ₃

In the first embodiment of the bonding method of the present invention, a vulcanizing agent, a vulcanization accelerator, an antioxidant, a reinforcing agent, and the like are mixed in advance in a flowable matrix composed of EPDM rubber. The fibrous material impregnated with the adhesive composition (for example, reinforcing short fibers) is put into a fluid matrix, for example, under a pressure of 130 to 170 mm, for 5 minutes to 1 hour. Vulcanization under the conditions: As a result, the rubber in the matrix: PI). \ I The rubber and EPDM rubber adhered to the fiber material are both vulcanized and crosslinked, and the fiber material is cured. It will adhere firmly to the matrix (internal bonding).

 In the second embodiment of the bonding method of the present invention, a vulcanizing agent, a vulcanization accelerator, an antioxidant, a reinforcing agent and the like are previously contained in an external object (for example, a rubber sheet) made of EPDM rubber. Keep it. Thereafter, in a state where the fiber material (for example, cloth) impregnated with the adhesive composition of the present invention is adhered (the cloth may be sandwiched like a cloth / rubber sheet Z cloth) under the above-described normal conditions. Vulcanize. As a result, the EPDM rubber in the external object and the EPDM rubber adhered to the fiber material are both vulcanized and crosslinked, and the fiber material is strongly bonded to the external object (external bonding). ).

 Specific examples of the vulcanizing agent include sulfur and its homologous elements (Se, Te), organic compounds containing sulfur, organic peroxides, metal oxides (MgO, Pb〇, ZnO, etc.), and organic compounds. Examples include polyamine, modified phenol resin, isocyanates, and the like. Specific examples of the carbosulfur accelerator include aldehyde ammonias, aldehyde amines, guanidines, thioperreas, thiazoles, thiurams, sulfenamides, dithiolbamates, and xanthates. Can be

 Other objects, features and advantages of the present invention will become apparent from the following description of the embodiments. BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, examples of the present invention will be described together with comparative examples, but the present invention is not limited to these examples.

[Example 1]

 (Preparation of adhesive composition)

E PDM rubber (Jen ingredients: dicyclohexylamine base Ntajen, Jen content: 3.5 wt _^0/0, ethylene content: 64.0 wt _^0/0, a propylene content: 32.5 wt _^0/0) 1. toluene 2 kg A solution was prepared by dissolving 10.8 kg in _ · In addition, an aqueous solution was prepared by dissolving 0.06 kg of potassium oleate as an emulsifier in 6 kg of water. The mixture was emulsified by stirring and mixing at 9000 rpm for 30 minutes with a special machine manufactured by Tokushu Kika Kogyo Co., Ltd. The obtained emulsion is distilled at a temperature of 40 to 60 ^: C and a reduced pressure of 150 to 100 mmHg (absolute pressure ^: 19, 950 to 13, 300 Pa), and toluene is distilled off. The concentrate was concentrated at 4,400 rpm to obtain an EPDM rubber latex having an average particle diameter of 0.8 to 1.2 m and a solid content of 40%.

On the other hand, 0.11 kg of resorcinol and 0.16 kg of 37% formalin were mixed and dissolved in an aqueous solution of 5 g of sodium hydroxide dissolved in 2.42 kg of water, and kept at 30 ^: C for 5 hours. To obtain RF resin aqueous liquid

 2.65 kg of EPDM rubber latex obtained by the above method, 2.69 kg of RF resin aqueous liquid and 1.52 kg of water were mixed, and further kept at 30 C for 2 hours to obtain an adhesive composition. .

 (Adhesion of fiber material)

 A cloth made of nylon 66 and fiber (10 mm X IO cm X O. 2 mm) was immersed in the adhesive composition prepared as described above, and then heat-treated at 235 C for 2 minutes to fix.

 Two cloths on which the adhesive composition was fixed as described above and three EPDVI rubber sheets (10 cm x 10 cm x 2 mm) prepared in the proportions shown in column A of Table 1 were used. Five layers were laminated (sheet Z cloth / sheet Z cloth Z sheet) and press-vulcanized at 160 C for 20 minutes to obtain an adhesive laminate of EPDM rubber and nylon 66 cloth.

(Hereinafter the margin)

table 1

 Rubber sheet

1) Esplen E50 1A (Sumitomo Chemical Industries, Ltd.)

 2) G n-bulge talent

 3) Tetramethylthiuram disulfide

 4) 2-Mercaptobenzazole

 5) Ethylene glycol dimethacrylate

[Examples 2 to 10 and Comparative Examples 1 to 6]

 In Examples 2 to 10 and Comparative Examples 1 to 6, an adhesive composition was obtained in the same manner as in Example 1 except that the EPDM rubber having the composition shown in Table 2 was used. Using the composition, an adhesive laminate was obtained in the same manner as in Example 1 except that rubber sheets having the compositions shown in Column B of Table 1 above were used for Examples 6 to 0 and Comparative Examples 4 to 6:

(Hereinafter the margin) Table 2

 Composition of EPDM rubber for latex Composition Gen component, N,, ^ "

 丄 Z s ri Ethylene content Propylene content

N o. (% By weight)

1 Dispensing pentagen 3.5 64.0 32.5

2 Dicycloventene 1 10.0 50.0 40.0

3 ethylidene norbornene 5.5 70.0 24.5

4 ethylidene nonolepo lenene 9.5 50.0 40.5

5 ethylidene nonolevonorenene 1 2.5 66.0 2 1.5

6 49. 0 5 1. 0

7 Shishoku Bentaeng 1.5 48.0 50.5

8 ethylidene nonolevosolenen 2.0 0.6 1.00 37. 0

[Confirmation of adhesive strength]

 For the adhesive laminates obtained in Examples 1 to 10 and Comparative Examples 1 to 6, the adhesive strength was evaluated by measuring the peel strength and the amount of rubber adhered after peeling, as described below. Table 3 shows:

 (Measurement of peel strength)

 Adhesion of EPDM rubber sheet and nylon 66 cloth obtained in each example and each comparative example to nylon 66 cloth The laminate was cut into a width of 25 mm.Then, the cut piece was placed between the center rubber sheet and the cloth in contact with it. Was peeled at a tensile speed of 5 OmmZ at a peeling angle of 180 degrees, and the force required for the peeling was measured as the peel strength.

 (Measurement of rubber adhesion amount)

The area of the rubber adhering to the surface of the cloth after the peel test was measured visually. The larger the attached area, the more the rubber of the rubber sheet is broken, indicating that the adhesive strength with the cloth (fiber material) is large. The scope of the claims

1. 3 to 15 weight of non-conjugated Gen component. / ₀ and a content for ethylene one Burobiren one non-conjugated diene terpolymer rubber latex and resorcinol one formaldehyde resin aqueous liquid adhesive composition -

2. With respect to 100 parts by weight of resorcinol-formaldehyde resin solids in the aqueous resin solution, 100-200 parts by weight of ethylene-propylene-nonconjugated gen ternary copolymer rubber solids in the rubber latex is used. 2. The adhesive composition according to claim 1, which is blended in a proportion of 100 parts by weight.

3. The terpolymer of the rubber in the latex, ethylene 4 0-8 0 weight _^0/0, propylene 1 5-6 0% by weight and a non-conjugated diene 5-1 5 weight ⁰ /. The adhesive composition according to claim 1, comprising:

4. The adhesive composition according to claim 1, wherein the non-conjugated gen of the terpolymer is selected from the group consisting of cyclopentadiene, ethylidene norbornene, and 1,4-hexadiene.

5. A method of adhering a fibrous material in a matrix comprising ethylene-propylene-non-conjugated gen terpolymer rubber,

 Prior to adhering the fiber material to the matrix, an ethylene-propylene-non-conjugated gen terpolymer containing 3 to 15% by weight of a non-conjugated gen component rubber latex and a resorcin-formaldehyde resin aqueous solution A method for bonding a fibrous material, comprising a preliminary step of impregnating and fixing the fibrous material in advance with an adhesive composition containing

6. The bonding method according to claim 5, wherein the preliminary step comprises a heat treatment of the fibrous material impregnated with the adhesive composition. Table 3

Evaluation of adhesive strength

 (Hereinafter the margin)

Ten

Claims

 [Evaluation]  From Table 3 above, the adhesive laminates of Examples 1 to 10 formed using an adhesive composition comprising an EPDM rubber latex containing 3 to 15% by weight of a non-conjugated gen component and an aqueous RF resin solution were ethylene. The peel strength is higher than that of the adhesive laminates of Comparative Examples 1 and 4 formed using an adhesive composition comprising a propylene copolymer latex and an RF resin aqueous liquid, and the rubber to the cloth (fiber material) after peeling Large amount of adhesion. In Comparative Examples 2, 3, 5, and 6 (not the prior art), an adhesive laminate was formed using an adhesive composition comprising an EPDM rubber latex and an RF resin aqueous liquid. Since the content of the synergistic gen is less than 3% by weight, the peel strength is relatively lower than in Examples 1 to 10, and the rubber adhesion amount is also reduced.  Therefore, according to the adhesive composition and the bonding method of the present invention, the fibrous material can be firmly bonded internally or externally to a matrix or an external object made of EPDM rubber by a relatively simple process. It can be used for various fiber reinforced composite products such as EPDM rubber belts, drawers, hoses, etc. 1 1 7. The bonding method according to claim 5, further comprising, after the preliminary step, a step of vulcanizing the rubber in the matrix and the rubber component in the adhesive composition together. 8. The bonding method according to claim 7, wherein the vulcanization step is performed under heat and pressure. 9. A method of adhering a fibrous material to an external object comprising ethylene-propylene-non-conjugated gen terpolymer rubber,  Prior to adhering the fiber material to the external object, an ethylene-propylene-non-conjugated gen terpolymer rubber latex containing 3 to 15% by weight of a non-conjugated gen component and a resorcin-formaldehyde resin aqueous liquid A method for bonding fiber materials, comprising a preliminary step of previously impregnating and fixing the fiber material with an adhesive composition comprising: 10. The bonding method according to claim 9, wherein the preliminary step includes heating the fibrous material impregnated with the adhesive composition. 11. The bonding method according to claim 9, further comprising a step of vulcanizing both the rubber in the external object and the rubber component in the adhesive composition after the preliminary step. 12. The bonding method according to claim 11, wherein the vulcanization step is performed under heat and pressure.