JPWO2011125224A1 - Copolymer latex for adhesive - Google Patents

Abstract

The adhesive copolymer latex contains latex particles in which at least a part of the first phase is covered with the second phase. Obtained by emulsion polymerization of a first phase monomer composition containing 0 to 5 wt% monomer and 55 to 90 wt% styrene monomer, the second phase is 50 to 90 wt% butadiene monomer %, A second phase monomer composition containing 10 to 30% by weight of a vinylpyridine monomer and 0 to 40% by weight of a styrene monomer.

Description

  The present invention relates to a copolymer latex for adhesive, and more particularly to a copolymer latex for adhesive that bonds rubber and fiber.

  Conventionally, fibers such as nylon, polyester, and aramid have been used as rubber reinforcing fibers for reinforcing rubber products such as tires, belts, and hoses.

  These rubber reinforcing fibers are usually used for an adhesive copolymer latex (generally a butadiene-vinylpyridine copolymer latex or a butadiene-vinylpyridine) in order to ensure their adhesion to rubber products. Adhesive treatment using an adhesive composition (hereinafter referred to as RFL) containing a copolymer copolymer latex and other rubber latex) and a resorcin-formalin resin (hereinafter referred to as RF resin). Has been.

  In this bonding treatment, the rubber reinforcing fibers are immersed in RFL and dried, and then heat treatment is performed at a high temperature of 170 ° C. or higher for nylon fibers and 220 ° C. or higher for polyester fibers or aramid fibers.

  As such a copolymer latex for adhesive used in RFL, for example, a butadiene-vinylpyridine copolymer latex having a specific monomer composition has been proposed (see, for example, Patent Documents 1 and 2 below). .

  For example, a copolymer latex composed of a butadiene-vinylpyridine copolymer latex having a specific monomer composition and SBR having a specific monomer composition has been proposed (see, for example, Patent Documents 3, 4, and 5 below). ).

  For example, a copolymer latex composed of copolymer particles having a specific structure has been proposed (see, for example, Patent Document 6 below).

Further, for example, a copolymer latex composed of butadiene-vinylpyridine copolymer latex having two kinds of specific monomer compositions has been proposed (for example, see Patent Document 7 below).
Japanese Patent Publication No. 7-78207 Japanese Patent Publication No. 8-32864 Japanese Examined Patent Publication No. 6-74401 Japanese Patent Publication No. 7-5871 JP 2007-154126 A Japanese Patent No. 3986654 JP-A-11-158289

  However, the above-described adhesion treatment has a disadvantage that the strength of the rubber reinforcing fiber is reduced by the heat treatment.

  On the other hand, in order to suppress the strength reduction of the rubber reinforcing fiber, it is considered that the heat treatment is performed at a temperature lower than the above temperature. There is a problem that.

  Then, the objective of this invention is providing the copolymer latex for adhesive agents which can improve the adhesive force of rubber | gum and a rubber reinforcing fiber, suppressing the strength fall of the rubber reinforcing fiber by heat processing. is there.

  In order to solve the above-described problems, the copolymer latex for an adhesive of the present invention contains latex particles in which at least a part of the first phase is covered with the second phase, and the first phase is a butadiene-based polymer. Obtained by emulsion polymerization of a first phase monomer composition comprising 10 to 45% by weight monomer, 0 to 5% by weight vinylpyridine monomer and 55 to 90% by weight styrene monomer, The two-phase emulsion polymerization of a second-phase monomer composition containing 50 to 90% by weight of a butadiene monomer, 10 to 30% by weight of a vinylpyridine monomer and 0 to 40% by weight of a styrene monomer It is characterized by being obtained.

  In the copolymer latex for an adhesive of the present invention, the first phase monomer composition is based on the total weight of the first phase monomer composition and the second phase monomer composition. Is preferably 10 to 50% by weight, and the second phase monomer composition is preferably 50 to 90% by weight.

  Moreover, in the copolymer latex for adhesives of this invention, it is suitable for the said 1st phase to coat | cover 50% or more of the surface area with the said 2nd phase.

  Moreover, in the copolymer latex for adhesives of this invention, it is suitable that the said 1st phase monomer composition contains 0 to 3 weight% of vinyl pyridine-type monomers.

  According to the copolymer latex for adhesive of the present invention, the adhesive force between rubber and rubber reinforcing fiber can be improved while suppressing the strength reduction of the rubber reinforcing fiber due to heat treatment.

FIG. 1 is a transmission electron micrograph of latex particles showing the latex particles of Example 1. FIG. 2 is a transmission electron micrograph of latex particles showing the latex particles of Example 6. FIG. 3 is a transmission electron micrograph of latex particles showing the latex particles of Example 5. FIG. 4 is a transmission electron micrograph of latex particles, showing the latex particles of Comparative Example 2.

Embodiment of the Invention

  The adhesive copolymer latex of the present invention contains latex particles composed of a first phase and a second phase having different compositions (different phase structure).

  The first phase is obtained by emulsion polymerization of a first phase monomer composition containing a butadiene monomer, a vinylpyridine monomer, and a styrene monomer.

  Examples of the butadiene monomer include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, and preferably 1,3-butadiene. Is mentioned. These butadiene monomers can be used alone or in combination of two or more.

  Examples of vinylpyridine monomers include 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, and preferably 2-vinylpyridine. These vinylpyridine monomers can be used alone or in combination of two or more.

  Examples of the styrene monomer include styrene, α-methylstyrene, monochlorostyrene, and preferably styrene. These styrenic monomers can be used alone or in combination of two or more.

  The first phase monomer composition comprises 10 to 45% by weight of butadiene monomer, preferably 15 to 40% by weight, and 0 to 5% by weight of vinylpyridine monomer (that is, vinylpyridine). The monomer may or may not be contained, and if it is contained, it is 5% by weight or less.), Preferably 0 to 3% by weight, and styrene monomer The polymer contains 55 to 90% by weight, preferably 60 to 85% by weight.

  When the blending ratio of the butadiene monomer is less than 10% by weight, the initial adhesive strength is lowered, and when it exceeds 45% by weight, the cord strength and the heat resistant adhesive strength are lowered.

  When the blending ratio of the vinylpyridine monomer exceeds 5% by weight, the initial adhesive strength is lowered.

  When the blending ratio of the styrenic monomer is less than 55% by weight, the heat-resistant adhesive strength is lowered.

  In addition, the first phase monomer composition is composed of other monomers (a butadiene monomer, a vinylpyridine monomer, and a styrene monomer) that can be copolymerized with other monomers. It can be replaced by a mass.

  Examples of other copolymerizable monomers include vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, and ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, and fumaric acid. Monomers, for example, ethylenically unsaturated carboxylic acid alkyl ester monomers such as methyl methacrylate, ethyl acrylate, butyl acrylate, etc., for example, ethylenically unsaturated carboxylic acids such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, etc. Examples thereof include hydroxyalkyl ester monomers, for example, amide monomers such as acrylamide and methacrylamide, and one or two or more of them can be used.

  The second phase is obtained by emulsion polymerization of a second phase monomer composition containing a butadiene monomer, a vinylpyridine monomer, and a styrene monomer.

  Examples of the butadiene monomer, vinylpyridine monomer, and styrene monomer include the same monomers as those exemplified in the first phase. The same applies to preferred monomers.

  In addition, the second phase monomer composition is a copolymer of a part of the contained monomers (butadiene monomer, vinylpyridine monomer and styrene monomer) with other monomers capable of being copolymerized. It can be replaced by a mass.

  Examples of the other copolymerizable monomers include the same monomers as the other copolymerizable monomers exemplified in the first phase.

  In the second phase monomer composition, the butadiene monomer is 50 to 90% by weight, preferably 60 to 80% by weight, and the vinylpyridine monomer is 10 to 30% by weight, preferably 10%. -25% by weight, and 0-40% by weight of styrenic monomer (that is, the styrenic monomer may or may not be contained, and if it is contained, 40 wt% or less.), Preferably 0 to 30 wt%.

  When the blending ratio of the butadiene monomer is less than 50% by weight, the initial adhesive strength is lowered, and when it exceeds 90% by weight, the cord strength and the heat resistant adhesive force are lowered.

  When the compounding ratio of the vinylpyridine monomer is less than 10% by weight, the initial adhesive strength and the heat-resistant adhesive force are lowered, and when it exceeds 30% by weight, the initial adhesive force is lowered.

  When the blending ratio of the styrene monomer exceeds 40% by weight, the initial adhesive strength and the heat resistant adhesive strength are reduced.

  The weight ratio of the first phase monomer composition to the total weight of the first phase monomer composition and the second phase monomer composition is, for example, 10 to 50% by weight, preferably The weight ratio of the second phase monomer composition is, for example, 50 to 90% by weight, and preferably 60 to 80% by weight.

  When the weight ratio of the first phase monomer composition is less than 10% by weight, the cord strength and the heat-resistant adhesive force may be reduced. In some cases, the initial adhesive strength and the heat-resistant adhesive strength may be reduced.

  In the total amount of the first phase monomer composition and the second phase monomer composition, the butadiene monomer is, for example, 40 to 80% by weight, preferably 50 to 70% by weight, vinyl. The pyridine monomer is contained in an amount of 5 to 25% by weight, preferably 7 to 17% by weight, and the styrene monomer is contained in an amount of 10 to 55% by weight, preferably 15 to 43% by weight.

  In order to obtain a copolymer latex, first, the first phase monomer composition is emulsion-polymerized to obtain a copolymer of the first phase monomer composition (that is, the first phase). In the presence of the copolymer of the first phase monomer composition, the second phase monomer composition is emulsion-polymerized to obtain a copolymer of the second phase monomer composition (that is, the second phase). )

  The second phase monomer composition is preferably added when the polymerization conversion rate of the first phase monomer composition reaches 60 to 90%.

  In order to emulsion-polymerize the first phase monomer composition and the second phase monomer composition, each monomer composition (each of the first phase monomer composition or the second phase monomer composition is used). ) Is added an emulsifier and a polymerization initiator.

  Examples of the emulsifier include nonionic surfactants such as polyethylene glycol alkyl ester type, alkyl phenyl ether type, and alkyl ether type, such as rosin acid salt, fatty acid salt, sulfate ester salt of higher alcohol, alkylbenzene sulfonate, Anionic surfactants such as alkyl diphenyl ether sulfonates, aliphatic sulfonates, aliphatic carboxylates, sulfate esters of nonionic surfactants, formalin condensates of naphthalene sulfonate, and the like, preferably, An anionic surfactant is mentioned, More preferably, the formalin condensate of a rosinate and a naphthalenesulfonate is mentioned. One or more emulsifiers can be used.

  The emulsifier is added, for example, at a ratio of 0.1 to 20 parts by weight, preferably 0.5 to 15 parts by weight with respect to 100 parts by weight of each monomer composition.

  The polymerization initiator is a radical polymerization initiator, for example, a water-soluble polymerization initiator such as potassium persulfate, sodium persulfate, ammonium persulfate, such as cumene hydroperoxide, benzoyl peroxide, t-butyl hydroperoxide. And oil-soluble polymerization initiators such as acetyl peroxide, diisopropylbenzene hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide. Preferably, the water-soluble polymerization initiator includes potassium persulfate, sodium persulfate, and ammonium persulfate, and the oil-soluble polymerization initiator includes cumene hydroperoxide.

  For example, the polymerization initiator is added in an amount of, for example, 0.01 to 3 parts by weight, preferably 0.05 to 2 parts by weight with respect to 100 parts by weight of each monomer composition.

  Moreover, in order to emulsion-polymerize each monomer composition, a reducing agent and a chain transfer agent can be added as needed.

  Examples of the reducing agent include sulfite, bisulfite, pyrosulfite, nitrite, nithionate, thiosulfate, formaldehyde sulfonate, benzaldehyde sulfonate, such as L-ascorbic acid and erythorbic acid. Carboxylic acids such as tartaric acid and citric acid and salts thereof, for example, reducing sugars such as dextrose and saccharose, and amines such as dimethylaniline and triethanolamine. Preferably, carboxylic acid and its salt are mentioned, More preferably, L-ascorbic acid and erythorbic acid are mentioned.

  For example, the reducing agent is added in a proportion of, for example, 0 to 1 part by weight, preferably 0 to 0.7 part by weight with respect to 100 parts by weight of the polymerization initiator.

  Examples of the chain transfer agent include alkyl mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, t-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, and n-stearyl mercaptan, such as dimethylxanthogen disulfide, diisopropyl. Xanthogen compounds such as xanthogen disulfide, for example, thiuram compounds such as tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetramethylthiuram monosulfide, such as 2,6-di-t-butyl-4-methylphenol, styrenated phenol, etc. Phenolic compounds such as allyl compounds such as allyl alcohol, eg halogenated carbonization such as dichloromethane, dibromomethane, carbon tetrabromide Elemental compounds such as vinyl ethers such as α-benzyloxystyrene, α-benzyloxyacrylonitrile, α-benzyloxyacrylamide, such as triphenylethane, pentaphenylethane, acrolein, metaacrolein, thioglycolic acid, thiomalic acid, 2- Examples include ethylhexyl thioglycolate and α-methylstyrene dimer, preferably alkyl mercaptan, and more preferably n-octyl mercaptan and t-dodecyl mercaptan. One or two or more chain transfer agents can be used.

  For example, the chain transfer agent is added at a ratio of, for example, 0 to 5 parts by weight, preferably 0.05 to 3 parts by weight, with respect to 100 parts by weight of each monomer composition.

  In the emulsion polymerization, if necessary, a hydrocarbon solvent can be added. Examples of the hydrocarbon include saturated hydrocarbons such as pentane, hexane, heptane, octane, cyclohexane, and cycloheptane, such as pentene, hexene, heptene, cyclopentene, cyclohexene, cycloheptene, 4-methylcyclohexene, and 1-methylcyclohexene. An unsaturated hydrocarbon etc. are mentioned, Preferably a cyclohexene is mentioned. Cyclohexene has a low boiling point and can be easily recovered and reused by, for example, steam distillation after polymerization, and is suitable from the viewpoint of environmental burden.

  As other additives, for example, electrolytes such as sodium hydroxide and sodium carbonate, polymerization inhibitors such as hydroquinone, polymerization accelerators, chelating agents, and the like can be added as necessary.

  Thereby, the surface of the granular first phase is partially coated with the second phase, or the surface of the granular first phase is completely coated with the second phase (core-shell structure). A copolymer latex for adhesive is prepared as an aqueous dispersion.

  The latex particles are preferably coated with 50% or more of the surface area of the first phase, more preferably 100% (that is, the entire surface) with the second phase.

  Further, the number average particle diameter of the latex particles is, for example, 50 to 200 nm, preferably 80 to 160 nm.

  In order to determine the coating state of the first phase by the second phase in the latex particles, for example, a cross section of the particles is observed using a transmission electron microscope.

  In order to observe the cross section of the particles using a transmission electron microscope, first, an osmium tetroxide aqueous solution is added to the adhesive copolymer latex, and the latex particles are subjected to electron staining (osmium staining). Note that osmium tetroxide is added to the double bond of 1,3-butadiene by electron staining.

  Next, an epoxy resin is added to the copolymer latex and then dried. Thereby, the solid substance of the epoxy resin containing latex particles can be obtained. That is, latex particles are coated (embedded) with an epoxy resin.

  Then, using an ultramicrotome, a section of a solid epoxy resin is cut out, and the cut out section is observed with a transmission electron microscope. In the transmission electron microscope observation of the particle cross section, the first phase with a relatively small content of 1,3-butadiene is observed thin, and the second phase with a relatively large content of 1,3-butadiene is observed deeply. Is done.

  As described above, when the cross section of the latex particle is observed using a transmission electron microscope, the cross section of the latex particle is 50% or more of the outer peripheral length of the first phase, more preferably 100% ( That is, the entire outer periphery) is covered with the second phase.

  In addition, in latex particle | grains, in order to control the coating state of the 1st phase by a 2nd phase, the weight ratio of an above-described 1st phase monomer composition and a 2nd phase monomer composition is changed, for example. .

  And the copolymer latex for adhesives of this invention is preferably mix | blended with the adhesive composition for adhere | attaching rubber | gum and rubber reinforcement fiber.

  The rubber is not particularly limited, and examples thereof include natural rubber, SBR, NBR, chloroprene rubber, polybutadiene rubber, polyisoprene rubber, and various modified rubbers thereof. Moreover, well-known additives, such as a filler, a softening agent, a vulcanizing agent, a vulcanization accelerator, can be mix | blended with rubber | gum, for example.

  Examples of the rubber reinforcing fiber include nylon fiber, polyester fiber, and aramid fiber. Moreover, it does not specifically limit as a form of these fibers, For example, a cord, a cable, a textile fabric, a canvas, a short fiber etc. are mentioned.

  The adhesive composition is obtained by blending and mixing a copolymer latex for adhesive and a resorcin-formalin resin.

  To prepare the adhesive composition, the adhesive copolymer latex and the resorcin-formalin resin are not particularly limited, but the resorcin-- is used for 100 parts by weight (solid content) of the adhesive copolymer latex. Formalin resin is blended, for example, 5 to 100 parts by weight, preferably 5 to 90 parts by weight.

  The adhesive composition may contain isocyanate, blocked isocyanate, ethylene urea, 2,6-bis (2,4-dihydroxyphenylmethyl) -4-chlorophenol, sulfur monochloride and resorcin, as necessary. And resorcin-formalin condensate and other modified resorcin-formalin resins, polyepoxides, modified polyvinyl chloride, carbon black and other adhesion aids, fillers, crosslinking agents, vulcanizing agents, vulcanization accelerators, etc. can do.

  In order to bond the rubber and the rubber reinforcing fiber, first, the adhesive composition is processed into the rubber reinforcing fiber.

  In order to treat the adhesive composition into the rubber reinforcing fiber, the rubber reinforcing fiber is immersed in the adhesive composition using, for example, a dipping machine. Then, for example, it is dried at 100 to 150 ° C., preferably 110 to 130 ° C., for example, 80 to 200 seconds, preferably 100 to 150 seconds, and then, for example, 180 to 300 ° C., preferably 200 to 260 Baking is performed at a temperature of, for example, 30 to 100 seconds, preferably 50 to 80 seconds.

  After the treatment, when the rubber is brought into contact with the rubber reinforcing fiber treated with the adhesive composition and the rubber and the rubber reinforcing fiber are heated and pressurized, the rubber and the rubber reinforcing fiber are bonded.

  And, by adjusting the adhesive composition using the copolymer latex for adhesive of the present invention, the adhesive strength between the rubber and the rubber reinforcing fiber is improved while suppressing the strength reduction of the rubber reinforcing fiber due to heat treatment. Can be made.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited to these Examples. In the examples, “part” and “%” indicating the blending ratio are based on weight.

1. Synthesis of copolymer latex for adhesive (1) Examples 1 to 8 and Comparative Example 1
In an autoclave equipped with a stirrer, 135 parts of water, 1 part of sodium naphthalenesulfonate / formalin condensate, 0.5 part of sodium hydroxide and 5.0 parts of potassium rosinate were added and dissolved.

  Next, the first phase monomer composition shown in Table 1 and 0.3 part of t-dodecyl mercaptan were added and emulsified.

  Thereafter, 0.5 part of potassium persulfate was added, the internal temperature was kept at 55 ° C., and the first phase monomer composition was polymerized.

  When the polymerization conversion rate of the first phase monomer composition reached 82%, the second phase monomer composition shown in Table 1 and 0.25 part of t-dodecyl mercaptan were continuously added. The polymerization was continued.

When the polymerization conversion rate reached 93% by weight, 0.1 part of hydroquinone was added to stop the polymerization, and the unreacted monomer was removed by distillation under reduced pressure to obtain a copolymer latex for adhesive.
(2) Comparative Example 2
In an autoclave equipped with a stirrer, 130 parts of water, 1 part of sodium naphthalenesulfonate / formalin condensate, 0.5 part of sodium hydroxide and 4 parts of potassium rosinate were added and dissolved.

  Next, the first phase monomer composition shown in Table 1 and 0.55 part of t-dodecyl mercaptan were added and emulsified.

  Thereafter, 0.5 part of potassium persulfate was added, the internal temperature was kept at 50 ° C., and the first phase monomer composition was polymerized.

  When the polymerization conversion rate reached 93%, 0.1 part of hydroquinone was added to stop the polymerization, and then the unreacted monomer was removed by distillation under reduced pressure to obtain a copolymer latex for adhesive. .

2. Observation of copolymer latex with electron microscope (confirmation of heterogeneous structure)
The obtained copolymer latex for adhesive was added with an osmium tetroxide aqueous solution and subjected to electron staining.

  Next, an epoxy resin was added to the adhesive copolymer latex and dried to obtain an epoxy resin solid containing latex particles. Thus, latex particles of the copolymer latex for adhesive were coated (embedded) with the epoxy resin.

  Next, a section of the epoxy resin was cut out using an ultramicrotome, and a cross section of the latex particles was photographed with a transmission electron microscope (JEOL JEM-1400). Transmission electron micrographs of latex particles are shown in FIGS. 1 shows latex particles of Example 1, FIG. 2 shows latex particles of Example 6, FIG. 3 shows latex particles of Example 5, and FIG. 4 shows latex particles of Comparative Example 2. Show.

  Then, the cross section of the particles was observed, and 1) presence / absence of a heterogeneous structure and 2) the covering state of the first phase by the second phase were visually evaluated.

2) Regarding the coating state of the first phase by the second phase, 100 particles were observed, and if 50 or more of them corresponded to the following evaluation criteria, the following evaluation was recognized.
<Evaluation criteria for coating state>
A: The second phase completely (100%) covers the first phase.
○: The second phase covers 50% or more of the first phase.
Δ: The second phase covers 50% or less of the first phase.
X: The second phase does not cover the first phase, and only one of the first phase and the second phase is recognized in one particle.

3. Preparation of Adhesive Composition (1) Adhesive Composition for Polyester Tire Cord (PET / Tire Cord) After adding 4 parts of 10% aqueous sodium hydroxide to 260 parts of water and stirring, 7.9 parts of resorcin, Then, 8.6 parts of 37% formalin aqueous solution was added, mixed with stirring, and aged at 30 ° C. for 6 hours to synthesize resorcin-formalin resin.

  Next, water was added to 100 parts of the copolymer latex for adhesive of each Example and each Comparative Example so that the solid content concentration of the adhesive composition was 16.5% and stirred, and then resorcin-formalin. The total amount of the resin and 11.4 parts of 28% aqueous ammonia were added and mixed with stirring.

Then, 46.3 parts of 27% blocked isocyanate dispersion (Meisei Chemical Industry Co., Ltd., SU-125F) was added and aged at 30 ° C. for 48 hours to obtain an adhesive composition for polyester tire cords. It was.
(2) Adhesive composition for 6-6 nylon tire cord (nylon tire cord) After adding 3.0 parts of 10% aqueous sodium hydroxide to 236 parts of water and stirring, 11.0 parts of resorcin, and Then, 16.2 parts of a 37% formalin aqueous solution was added, mixed with stirring, and aged at 25 ° C. for 6 hours to synthesize a resorcin-formalin resin.

  Next, water was added to 100 parts of the copolymer latex for adhesive of each Example and each Comparative Example so that the solid content concentration of the adhesive composition was 16.5% and stirred, and then resorcin-formalin. The total amount of the resin and 13.0 parts of 28% aqueous ammonia were added and mixed with stirring.

  Thereafter, aging was carried out at 25 ° C. for 18 hours to obtain an adhesive composition for 6-6 nylon tire cord.

4). Evaluation (1) Tire cord dipping treatment A polyester cord (1500D / 2) or 6-6 nylon tire cord (1260D) pretreated with the adhesive composition obtained by using a test single cord dipping machine. / 3) and then dried at 120 ° C. for 120 seconds, and then the polyester tire cord was baked at 240 ° C. for 60 seconds and the 6-6 nylon tire cord was baked at 220 ° C. for 60 seconds.
(2) Rubber A rubber was prepared according to the following formulation.
<Rubber prescription>
Natural rubber 70 parts SBR rubber 30 parts FEF carbon 40 parts Process oil 4 parts Antigen RD (* 1) 2 parts Stearic acid 1.5 parts Zinc white 5 parts Vulcanization accelerator DM (* 2) 0.9 parts Sulfur 7 parts * 1: 2,2,4-trimethyl-1,2-dihydroquinoline polymer (manufactured by Sumitomo Chemical Co., Ltd.)
* 2: Measurement of fiber strength of dibenzothiazyl disulfide (3) Polyester tire cord (1500D / 2) or 6-6 nylon tire cord (1260D / The fiber strength (cord strength) of 3) was measured according to JIS-L1017. The results are shown in Table 2.
(4) Measurement of adhesive strength (4-1) Polyester tire cord The polyester tire cord treated with the adhesive composition of each example and each comparative example was sandwiched with rubber, and it was 20 minutes at 160 ° C. (initial adhesive strength) (Evaluation conditions), and vulcanization press was performed at 170 ° C. for 50 minutes (heat resistant adhesive strength evaluation conditions).

The initial adhesive strength and heat-resistant adhesive strength between rubber and rubber reinforcing fiber were measured according to ASTM D2138-67 (H Pull Test). The results are shown in Table 2.
(4-2) Nylon / Tire Cord Nylon / Tire Cord treated with the adhesive composition of each Example and each Comparative Example was sandwiched with rubber as in the case of the above-mentioned polyester / tyre cord, and 20 minutes at 160 ° C. Vulcanizing press was performed under the conditions of (initial adhesive strength evaluation conditions).

  The initial adhesive strength between rubber and rubber reinforcing fiber was measured according to ASTM D2138-67 (H Pull Test). The results are shown in Table 2.

  In addition, although the said invention was provided as embodiment of illustration of this invention, this is only a mere illustration and must not be interpreted limitedly. Modifications of the present invention apparent to those skilled in the art are intended to be included within the scope of the following claims.

  The copolymer latex for adhesive of the present invention is blended in an adhesive composition and used for bonding rubber and rubber reinforcing fiber.

Claims (4)

Containing latex particles wherein at least a portion of the first phase is coated with the second phase;
The first phase is
Obtained by emulsion polymerization of a first phase monomer composition comprising 10 to 45 wt% butadiene monomer, 0 to 5 wt% vinylpyridine monomer and 55 to 90 wt% styrene monomer,
The second phase is
Obtained by emulsion polymerization of a second phase monomer composition containing 50-90 wt% butadiene monomer, 10-30 wt% vinylpyridine monomer and 0-40 wt% styrene monomer. Copolymer latex for adhesives, characterized in that   The weight ratio of the first phase monomer composition is 10 to 50% by weight with respect to the total weight of the first phase monomer composition and the second phase monomer composition, The copolymer latex for an adhesive according to claim 1, wherein the weight ratio of the two-phase monomer composition is 50 to 90% by weight.   The copolymer latex for an adhesive according to claim 1, wherein 50% or more of the surface area of the first phase is covered with the second phase.   The copolymer latex for adhesive according to claim 1, wherein the first phase monomer composition contains 0 to 3 wt% of a vinylpyridine monomer.