TWI512068B - Copolymer latex for adhesives - Google Patents

Description

Copolymer latex for subsequent agent

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a copolymer latex for an adhesive, and more particularly to a copolymer latex for rubber and fiber followed by an adhesive.

Conventionally, as a rubber reinforcing fiber for reinforcing rubber products such as tires, conveyor belts, and hoses, fibers such as nylon (nylon), polyester, and linaloamine are used.

Usually, in order to secure the adhesion of these rubber-reinforcing fibers to rubber articles, a copolymer latex containing an adhesive (generally a butadiene-vinylpyridine copolymer latex or a butadiene-vinylpyridine copolymer) is used. The rubber reinforcing fiber is subjected to a subsequent treatment with a binder composition of a resorcinol-formalin resin (hereinafter referred to as RF resin) and a binder composition of resorcinol-formalin resin (hereinafter referred to as RF resin).

In this subsequent treatment, the rubber-reinforcing fiber is immersed in RFL, and after drying, heat treatment is performed, and the nylon fiber is heat-treated at 170 ° C or higher, and the polyester fiber or linalin fiber is heat-treated at a high temperature of 220 ° C or higher.

As the copolymer latex for the adhesive used in the RFL, for example, a butadiene-vinylpyridine copolymer latex having a specific monomer composition is proposed (for example, refer to Patent Documents 1 and 2 below).

Further, for example, there is a copolymer of a butadiene-vinylpyridine copolymer having a specific monomer composition and a specific monomer composed of a copolymer latex of SBR (styrene-butadiene rubber) (for example, Patent Documents 3, 4, and 5).

Further, for example, a copolymer latex composed of copolymer particles having a specific structure is proposed (for example, refer to Patent Document 6 below).

Further, for example, a copolymer latex composed of a butadiene-vinylpyridine copolymer latex having a specific monomer composition of two types is proposed (for example, refer to Patent Document 7 below).

[Previous Technical Literature]

Patent Document 1: Japanese Patent Publication No. 7-78207

Patent Document 2: Japanese Patent Publication No. 8-32864

Patent Document 3: Japanese Special Fair 6-74401

Patent Document 4: Japanese Special Fair 7-5871

Patent Document 5: Japanese Laid-Open Patent Publication No. 2007-154126

Patent Document 6: Japanese Patent No. 3986654

Patent Document 7: Japanese Patent Laid-Open No. Hei 11-158289

However, in the above-described subsequent treatment, there is a problem that the strength of the rubber reinforcing fiber is lowered due to the heat treatment.

On the other hand, in order to suppress the decrease in the strength of the fiber for reinforcing rubber, it is considered that the heat treatment is performed at a lower temperature than the above temperature, but when the temperature of the heat treatment is low, there is a problem that the adhesion between the rubber and the rubber reinforcing fiber is lowered.

Here, an object of the present invention is to provide a copolymer latex for an adhesive which can improve the adhesion between the rubber and the rubber-reinforcing fiber while suppressing the decrease in the strength of the rubber-reinforcing fiber due to the heat treatment.

In order to solve the above problems, the copolymer latex for an adhesive according to the present invention is characterized in that it contains latex particles obtained by coating at least a part of the first phase with the second phase, and the first phase is made of butadiene. Emulsified polymerization of 10% to 45% by weight of a monomer, 0 to 5% by weight of a vinylpyridine monomer, and 55 to 90% by weight of a styrene monomer, and the second phase Emulsified polymerization of a second phase monomer composition comprising 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 And got it.

Further, in the copolymer latex for an adhesive of the present invention, 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 preferably The weight ratio of the above-mentioned second phase monomer composition is from 50 to 90% by weight, based on 10 to 50% by weight.

Moreover, in the copolymer latex for an adhesive agent of the present invention, 50% or more of the surface area of the first phase is preferably coated with the second phase.

Further, in the copolymer latex for an adhesive of the present invention, the first phase monomer composition preferably contains 0 to 3% by weight of a vinylpyridine monomer.

According to the copolymer latex for an adhesive agent of the present invention, the adhesion between the rubber and the rubber-reinforcing fiber can be improved while suppressing the decrease in the strength of the rubber-reinforcing fiber due to the heat treatment.

(Best form of implementing the invention)

The copolymer latex for an adhesive of the present invention contains latex particles composed of a first phase and a second phase having mutually different compositions (heterophase structures).

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-based monomer include 1,3-butadiene, 2-methyl-1,3-butadiene, and 2,3-dimethyl-1,3-butadiene. And preferred is 1,3-butadiene. These butadiene monomers may be used alone or in combination of two or more.

Examples of the vinyl pyridine-based monomer include 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, and 2-methyl-5-vinylpyridine. Preferred examples thereof include 2 - vinyl pyridine. These vinyl pyridine monomers may be used alone or in combination of two or more.

Examples of the styrene-based monomer include styrene, α-methylstyrene, and monochlorostyrene. Preferred examples thereof include styrene. These styrene monomers may be used alone or in combination of two or more.

The first phase monomer composition contains: from 10 to 45% by weight of the butadiene monomer, preferably from 15 to 40% by weight; from 0 to 5% by weight of the vinylpyridine monomer (that is, a vinyl group) The pyridine-based monomer may or may not be contained, and when it is contained, it is 5% by weight or less, and preferably 0 to 3% by weight; and the styrene-based monomer is 55 to 90% by weight, and 60 to 85% by weight. % is better.

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

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

When the blending ratio of the styrene monomer is less than 55% by weight, the heat-resistant adhesive force is lowered, and when it exceeds 90% by weight, the initial adhesion force and the heat-resistant adhesive force are lowered.

At the same time, a part of the monomer (butadiene monomer, vinyl pyridine monomer, and styrene monomer) contained in the monomer composition of the first phase may be substituted with other monomers copolymerizable. .

Examples of other monomers which can be copolymerized 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. The acid monomer is, for example, an ethylenically unsaturated carboxylic acid alkyl ester monomer such as methyl methacrylate, ethyl acrylate or butyl acrylate, for example, a vinyl group such as β-hydroxyethyl acrylate or β-hydroxyethyl methacrylate. The unsaturated carboxylic acid hydroxyalkyl ester-based monomer, for example, a guanamine-based monomer such as acrylamide or methacrylamide, may be used alone or in combination of two or more.

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, the vinylpyridine monomer, and the styrene monomer are the same as those exemplified for the first phase. At the same time, the preferred monomers are the same.

Further, a part of the monomer (butadiene monomer, vinylpyridine monomer, and styrene monomer) contained in the second phase monomer composition may be substituted with other monomers copolymerizable. .

As the other monomer which can be copolymerized, the same monomer as the other monomer which can be copolymerized as exemplified in the first phase can be exemplified.

The second phase monomer composition contains: 50 to 90% by weight of the butadiene monomer, preferably 60 to 80% by weight; 10 to 30% by weight of the vinylpyridine monomer, and 10 to 25% by weight Preferably, the styrene monomer is 0 to 40% by weight (that is, it may or may not contain a styrene monomer, and when it is contained, it is 40% by weight or less), and 0 to 30% by weight. good.

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

When the blending ratio of the vinyl pyridine monomer is less than 10% by weight, the initial adhesion force and the heat resistance adhesion force are lowered, and when it exceeds 30% by weight, the initial adhesion force is lowered.

When the blending ratio of the styrene monomer exceeds 40% by weight, the initial adhesion force and the heat resistant adhesion are lowered.

Further, 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, and preferably 20 to 40% by weight. 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 linear strength and the heat-resistant adhesive force may be lowered. When the weight ratio exceeds 50% by weight, the first phase cannot be covered by the second phase, and the initial adhesion and heat resistance are maintained. Then there is a decline in power.

Further, the total weight of the first phase monomer composition and the second phase monomer composition contains: a butadiene monomer, for example, 40 to 80% by weight, and preferably 50 to 70% by weight; vinyl pyridine The monomer is 5 to 25% by weight, preferably 7 to 17% by weight; and the styrene monomer is 10 to 55% by weight, and preferably 15 to 43% by weight.

Further, 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), and then the first phase monomer composition is obtained. The second phase monomer composition is emulsified and polymerized in the presence of the copolymer to obtain a copolymer of the second phase monomer composition (that is, the second phase).

Meanwhile, it is preferred to add the second phase monomer composition at the time when the polymerization conversion ratio of the monomer composition of the first phase becomes 60 to 90%.

In order to emulsify and polymerize the first phase monomer composition and the second phase monomer composition, an emulsifier and polymerization are added to each of the monomer compositions (the first phase monomer composition or the second phase monomer composition). Starting agent.

Examples of the emulsifier include nonionic surfactants such as an alkyl ester type of polyethylene glycol, an alkylphenyl ether type, and an alkyl ether type, for example, a rosin acid salt, a fatty acid salt, and a sulfate of a higher alcohol. Salt, alkylbenzenesulfonate, alkyl diphenyl ether sulfonate, aliphatic sulfonate, aliphatic carboxylate, sulfate ester of nonionic surfactant, and fumarin condensation of naphthalenesulfonate An anionic surfactant such as a substance is preferable, and an anionic surfactant is preferable, and a humic acid salt of a rosin salt or a naphthalenesulfonate is more preferable. One type or two or more types of emulsifiers can be used.

The emulsifier is added in a ratio of, for example, 0.1 to 20 parts by weight, based on 100 parts by weight of each monomer composition, and the emulsifier is preferably added in a ratio of 0.5 to 15 parts by weight.

The polymerization initiator is a radical polymerization initiator, and examples thereof include water-soluble polymerization initiators such as potassium persulfate, sodium persulfate, and ammonium persulfate; for example, cumene hydroperoxide, peroxidation. Benzoyl peroxide, t-butyl hydroperoxide, Acetyl Peroxide, diisopropylbenzene hydroperoxide, 1 An oil-soluble polymerization initiator such as 1,3,3-tetramethylbutyl hydroperoxide. Preferable examples thereof include potassium persulfate, sodium persulfate and ammonium persulfate as water-soluble polymerization initiators, and cumene hydroperoxide as an oil-soluble polymerization initiator.

The polymerization initiator is added in a ratio of, for example, 0.01 to 3 parts by weight based on 100 parts by weight of each monomer composition, and the polymerization initiator is preferably added in a ratio of 0.05 to 2 parts by weight.

Further, in the emulsion polymerization of each monomer composition, a reducing agent or a chain transfer agent may be added as needed.

As the reducing agent, for example, sulfite, bisulfite, pyrosulfite, dithionite, dithionite, thiosulfate, formaldehyde sulfonate, benzaldehyde The sulfonate is, for example, a carboxylic acid such as L-ascorbic acid, Erythorbic acid, tartaric acid or citric acid, or a salt thereof, for example, a reducing saccharide such as glucose or sucrose, for example, an amine such as dimethylaniline or triethanolamine. Preferred examples thereof include carboxylic acids and salts thereof, and more preferred examples are L-ascorbic acid and isoascorbic acid.

The reducing agent is added in a ratio of, for example, 0 to 1 part by weight, based on 100 parts by weight of the polymerization initiator, and it is more preferable to add the reducing agent in a ratio of 0 to 0.7 part by weight.

As the chain transfer agent, for example, n-hexyl mercaptan, n-octyl mercaptan, tri-octyl mercaptan, n-dodecyl mercaptan, tertiary dodecyl mercaptan, n-stearyl An alkyl thiol such as a thiol, such as a xanthogen compound such as dimethyl xanthogen disulfide or diisopropyl xanthate, such as tetramethyl thiuram disulfide Thiuram compounds such as tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetramethylthiuram monosulfide, such as 2,6-di-tertiary butyl-4-methylphenol, styrene a phenolic compound such as phenol; for example, an allyl compound such as allyl alcohol; for example, a halogenated hydrocarbon compound such as dichloromethane, dibromomethane or carbon tetrabromide, such as α-benzyloxystyrene or α-benzyloxyacrylonitrile a vinyl ether such as α-benzyloxypropenylamine, such as triphenylethane, pentaphenylethane, acrolein, methacrolein, thioglycolic acid, mercapto succinic acid, 2-ethylhexyl thioglycolate An ester, an α-methylstyrene dimer, etc., preferably an alkyl mercaptan, and more preferably an n-octyl mercaptan , a tertiary dodecyl mercaptan. One type or two or more types of chain transfer agents can be used.

The chain transfer agent is added in a ratio of, for example, 0 to 5 parts by weight, based on 100 parts by weight of each monomer composition, and the chain transfer agent is preferably added in a ratio of 0.05 to 3 parts by weight.

Further, in the emulsion polymerization, a hydrocarbon solvent may be added as needed. Examples of the hydrocarbon include saturated hydrocarbons such as pentane, hexane, heptane, octane, cyclohexane, and cycloheptane, such as pentene, hexene, heptene, cyclopentene, and cyclohexene. An unsaturated hydrocarbon such as cycloheptene, 4-methylcyclohexene or 1-methylcyclohexene, and the like, preferably cyclohexene. From the viewpoint of environmental load which is easily recovered and reused by steam distillation or the like after the completion of the low-boiling polymerization, cyclohexene is suitable.

Further, as another additive, for example, an electrolyte such as sodium hydroxide or sodium carbonate, a polymerization inhibitor such as hydroquinone, a polymerization accelerator, a chelator, or the like may be added.

By this, a latex particle in which one surface of the first phase of the granular phase is covered by the second phase or the surface (core/shell structure) of the first phase which is completely covered by the second phase is formed The aqueous dispersion is used to prepare a copolymer latex for the adhesive.

Further, it is preferable that the latex particles are coated with the second phase by 50% or more (more preferably 100% (i.e., all surfaces)) of the surface area of the first phase.

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

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

When the cross section of the particles was observed using a transmission electron microscope, first, an aqueous solution of ruthenium tetroxide was added to the copolymer latex for an adhesive to electronically dye the latex particles (dyeing). At the same time, osmium tetroxide is added to the double bond of 1,3-butadiene by electron dyeing.

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

Then, a section of the epoxy solid matter was cut out using an ultramicrotome, and the cut slice was observed by a transmission electron microscope. In the observation of the cross section of the particle section, it was observed that the first phase containing a relatively small amount of 1,3-butadiene was light, and the amount of 1,3-butadiene was observed to be relatively large. The 2 phase is thicker.

Further, as described above, when the cross section of the latex particles is observed by transmission electron microscopy, in the cross section of the latex particles, 50% or more (preferably 100% (i.e., all outer circumferences)) of the outer circumference length of the first phase passes through 2 phases are covered.

At the same time, in the latex particles, in order to control the state in which the first phase is covered by the second phase, for example, the weight ratio of the first phase monomer composition to the second phase monomer composition described above is changed.

Further, the copolymer latex for an adhesive of the present invention is preferably formulated to form a rubber and a rubber reinforcing fiber followed by an adhesive composition.

The rubber is not particularly limited, and examples thereof include natural rubber, SBR, NBR (nitrile rubber), chloroprene rubber, polybutadiene rubber, polyisoprene rubber, and various modified rubbers thereof. Wait. Further, in the rubber, for example, a conventional additive such as a filler, a softener, a vulcanizing agent, or a vulcanization accelerator may be blended.

Examples of the rubber reinforced fiber include nylon fibers, polyester fibers, and linaloamide fibers. Moreover, the form of these fibers is not particularly limited, and examples thereof include a cord, a cable, a woven fabric, a canvas, and a short fiber.

The composition of the subsequent agent is obtained by mixing a copolymer latex and a resorcinol-formalin resin with an adhesive.

When the adhesive composition is prepared, the copolymer latex for the adhesive and the resorcin-formalin resin are not particularly limited, and for example, 5 to 100 parts by weight based on 100 parts by weight (solids) of the copolymer latex for the adhesive. (preferably 5 to 90 parts by weight) of the benzenediol-formalin resin.

Further, in the adhesive composition, isocyanate, blocked isocyanate, ethylene urea, 2,6-bis(2,4-dihydroxyphenylmethyl)-4-chlorophenol, and one may be blended as needed. Modified resorcinol-formalin resin, polyepoxide, modified polyvinyl chloride, carbon black, etc., followed by a mixture of sulfur chloride and resorcinol and a mixture of resorcinol-formalin condensate Auxiliaries, fillers, crosslinking agents, vulcanizing agents, vulcanization accelerators, and the like.

Further, in order to adhere the rubber to the rubber reinforcing fiber, first, the adhesive composition is treated in the rubber reinforcing fiber.

In order to treat the adhesive composition in the rubber reinforced fiber, for example, a rubber reinforced fiber is impregnated into the adhesive composition using a dip machine or the like. Thereafter, it is dried, for example, at 100 to 150 ° C (preferably 110 to 130 ° C), for example, 80 to 200 seconds (preferably 100 to 150 seconds), and thereafter, for example, at 180 to 300 ° C (preferably The heating is performed by heating, for example, from 30 to 100 seconds (preferably from 50 to 80 seconds).

Then, after the above treatment, the rubber is brought into contact with the rubber reinforcing fiber treated with the adhesive composition, and when the rubber and the rubber reinforcing fiber are heated and pressurized, the rubber and the rubber reinforcing fiber are followed.

When the adhesive composition for the adhesive agent for the adhesive of the present invention is used, the adhesive strength of the rubber-reinforced fiber can be improved while suppressing the decrease in the strength of the rubber-reinforcing fiber due to the heat treatment.

(Example)

Hereinafter, the present invention will be specifically described by way of examples, but the invention is not limited to the examples. Meanwhile, in the examples, the "parts" and "%" indicating the blending ratio are based on the weight.

1. Synthesis of copolymer latex for adhesive (1) Examples 1 to 8 and Comparative Example 1

In a pressure cooker 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, 0.3 parts of the first phase monomer composition shown in Table 1 and tertiary dodecyl mercaptan were added and emulsified.

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

When the polymerization conversion ratio of the monomer composition of the first phase reached 82%, the second phase monomer composition shown in Table 1 and 0.25 parts of the tertiary dodecyl mercaptan were continuously added, and the polymerization was continued.

When the polymerization conversion ratio 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 an adhesive.

(2) Comparative Example 2

In a pressure cooker 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, 0.55 parts of the first phase monomer composition shown in Table 1 and tertiary lauryl mercaptan were added and emulsified.

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

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

2. Electron microscopic observation of copolymer latex (consensus structure confirmation)

In the obtained copolymer latex for an adhesive, an aqueous solution of osmium tetroxide was added for electronic dyeing.

Next, an epoxy resin is added to the copolymer latex for an adhesive and dried to obtain a solid matter of an epoxy resin containing latex particles. Thereby, the latex particles of the copolymer latex for the adhesive are coated (embedded) with an epoxy resin.

Next, a section of the epoxy resin was cut out using an ultramicrotome, and a section of the latex particle was photographed by a transmission electron microscope (JEOL-JE-1400). A transmission electron micrograph of the latex particles is shown in Figures 1 to 4.

Fig. 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.

Then, the cross section of the particles was observed and visually evaluated: 1) whether or not the phase structure was present, and 2) the state in which the first phase was covered by the second phase.

At the same time, 2) observation of 100 particles by the state in which the second phase is covered with the first phase, and if 50 or more of them correspond to the following evaluation criteria, it is determined as the following evaluation.

<Evaluation criteria of the covered state>

◎: The second phase completely (100%) covered the first phase.

○: The second phase covers 50% or more of the first phase.

△: The second phase is covered by the first phase by 50% or less.

x: The second phase does not cover the first phase, and only one of the first phase or the second phase can be confirmed in one particle.

3. Modulation of the composition of the adhesive (1) Adhesive composition for polyester-tire cord (PET-Tire Cord)

After adding 4 parts of 10% aqueous sodium hydroxide solution to 260 parts of water and stirring, 7.9 parts of resorcinol and 8.6 parts of 37% formalin aqueous solution were added, stirred and mixed, and aged at 30 ° C for 6 hours to synthesize resorcinol-foma. Forest resin.

Next, in 100 parts of the copolymer latex for each of the examples and the comparative examples, water was added to adjust the solid content of the adhesive composition to 16.5%, and after stirring, the total amount of resorcin-formalin resin was added. It was mixed with 12% ammonia water and 11.4 parts with stirring.

Thereafter, 46.3 parts of a 27% blocked isocyanate dispersion (SU-125F manufactured by Mingsei Chemical Industry Co., Ltd.) was added, and the mixture was aged at 30 ° C for 48 hours to obtain an adhesive composition for a polyester-tire cord.

(2) 6-6 nylon-tire cord (Nylon-tire cord) adhesive composition

After adding 3.0 parts of a 10% aqueous sodium hydroxide solution to 236 parts of water and stirring, 11.0 parts of resorcinol and 16.2 parts of a 37% aqueous solution of formalin were added and stirred and mixed, and aged at 25 ° C for 6 hours to synthesize resorcinol - Formalin resin.

Next, in 100 parts of the copolymer latex for each of the examples and the comparative examples, water was added to adjust the solid content of the adhesive composition to 16.5%, and after stirring, the total amount of resorcin-formalin resin was added. It was mixed with 28% ammonia water 13.0 parts with stirring.

Thereafter, the mixture was aged at 25 ° C for 18 hours to obtain an adhesive composition for 6-6 nylon-tire cord.

4. Evaluation (1) Tire cord impregnation treatment

The pretreated polyester-tire cord (1500D/2) or 6-6 nylon-tire cord (1260D/3) was impregnated in the resulting adhesive composition using a test single cord dipping machine, after which, at 120 After drying at ° C for 120 seconds, the polyester-tire cord was welded at 240 ° C for 60 seconds, and the 6-6 nylon-tire cord was welded at 220 ° C for 60 seconds.

(2) Rubber

The rubber was prepared by the following formulation.

<rubber>

Natural rubber 70 parts

SBR rubber 30 parts

FEF carbon 40 parts

Operating 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 2.7 parts

*1: 2,2,4-trimethyl-1,2-dihydroanthracene polymer (manufactured by Sumitomo Chemical Co., Ltd.).

*2: Dibenzothiazolyl disulfide

(3) Determination of fiber strength

The fiber strength of the polyester-tire cord (1500D/2) or 6-6 nylon-tire cord (1260/3) treated by the adhesive compositions of the respective examples and comparative examples was measured in accordance with JIS-L 1017 ( Line strength). The results are shown in Table 2.

(4) Next force measurement (4-1) Polyester - Tire Cord

The polyester-tire cord treated by the adhesive composition of each of the examples and the comparative examples was rubbed with rubber at 20 ° C for 20 minutes (initial adhesion evaluation condition) and 170 ° C for 50 minutes (heat resistance adhesion evaluation condition). Vulcanization pressurization is carried out under the conditions.

The initial adhesion and heat-resistant adhesion of the rubber and rubber reinforced fibers were measured in accordance with ASTM D2138-67 (H Pull Test). The results are shown in Table 2.

(4-2) Nylon-Tire Curtain

In the same manner as in the case of the above-described polyester-tire cord, the condition of the nylon-tire cord treated with the adhesive composition of each of the examples and the comparative examples was 20 minutes at 160 ° C (initial adhesion evaluation condition). Vulcanization pressurization is carried out.

The initial adhesion of the rubber to the rubber reinforced fiber was measured in accordance with ASTM D2138-67 (H Pull Test). The results are shown in Table 2.

The above-described invention is provided as an exemplification of the invention, but these are merely illustrative and should not be construed as limiting. Modifications of the present invention which can be understood by those skilled in the art are also included in the scope of the patent application described below.

(industrial availability)

The adhesive of the present invention is formulated with a copolymer latex in an adhesive composition for use in bonding rubber and rubber reinforcing fibers.

Fig. 1 is a transmission electron micrograph of the latex particles, and shows the latex particles of Example 1.

Fig. 2 is a transmission electron micrograph of the latex particles, and shows the latex particles of Example 6.

Fig. 3 is a transmission electron micrograph of the latex particles, and shows the latex particles of Example 5.

Fig. 4 is a transmission electron micrograph of the latex particles, and shows the latex particles of Comparative Example 2.

Since the pictures in this case are all photographs, they are not representative figures of the case. Therefore, there is no designated representative map in this case.

Claims (1)

A copolymer latex for an adhesive comprising latex particles obtained by coating at least a part of a first phase with a second phase, wherein the first phase is contained in an amount of 10 to 45% by weight based on the butadiene-based monomer; Emulsified polymerization of a first phase monomer composition of a vinyl pyridine monomer of 0 or more and less than 3% by weight, and 55 to 90% by weight of a styrene monomer, and the second phase is obtained by containing Emulsified polymerization of a second phase monomer composition of 50 to 90% by weight of an olefinic monomer, 10 to 30% by weight of a vinylpyridine monomer, and 0 to 40% by weight of a styrene monomer, wherein The weight ratio of the first phase monomer composition to the total weight of the first phase monomer composition is 10 to 40% by weight based on the total weight of the first phase monomer composition and the second phase monomer composition, and the weight of the second phase monomer composition The ratio is 60 to 90% by weight; the first phase is 50% or more of the surface area covered by the second phase.