KR20150083086A - Method for producing copolymer latex for adhesives - Google Patents

Abstract

A method for producing a copolymer latex for an adhesive, comprising: preparing a copolymer latex comprising an aliphatic conjugated diene monomer in an amount of 35 mass% to 75 mass%, a vinylpyridine monomer in an amount of 5 mass% to 25 mass%, and 0 mass% (A), wherein the monomer composition (a) is a mixture of an aliphatic conjugated diene monomer (a) and an aliphatic conjugated diene monomer (a) in an amount of 30% or more and less than 60% (B) comprising 35 mass% or more and 75 mass% or less, 5 mass% or more and 25 mass% or less of vinyl pyridine monomer, and 0 mass% or more and 60 mass% or less of other monomer copolymerizable therewith, And polymerizing.

Description

METHOD FOR PRODUCING COPOLYMER LATEX FOR ADHESIVES BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a method for producing a copolymer latex for an adhesive, and more particularly, to a method for producing a copolymer latex for an adhesive which bonds a rubber to a fiber.

Background Art [0002] Heretofore, fibers such as nylon, polyester, aramid and glass have been used as rubber reinforcing fibers for reinforcing rubber products such as tires, belts and hoses.

These rubber reinforcing fibers are usually used in rubber products in order to secure their adhesiveness by using a copolymer latex for an adhesive (generally, a latex of a butadiene-vinylpyridine copolymer, a latex of a butadiene-vinylpyridine, (Hereinafter referred to as " RFL ") containing a resorcinol-formaldehyde resin (hereinafter referred to as " RFL "

As the copolymer latex for the adhesive contained in such RFL, for example, a conjugated diene monomer, an ethylenically unsaturated acid monomer, a vinyl pyridine, and other monomers copolymerizable therewith are first added to 2.5 to 60 mass% (Including an ethylenically unsaturated acid and a conjugated diene monomer) is polymerized until the polymerization conversion rate reaches at least 60%, and then the remaining monomers are polymerized (see, for example, , See Patent Document 1 below).

Japanese Patent Publication No. 6-99487

In the latex described in Patent Document 1, the second-stage monomer (the remaining monomer in Patent Document 1) is polymerized after the polymerization conversion rate of the first-stage monomer is 60% or more.

Therefore, it is difficult to shorten the polymerization time of the first-stage monomer, and it is difficult to improve the productivity of the latex.

Therefore, an object of the present invention is to provide a process for producing a copolymer latex for an adhesive, which can improve the productivity of a copolymer latex for an adhesive, while securing an adhesive force to rubber-reinforcing fibers of an adhesive copolymer latex .

The method for producing a copolymer latex for an adhesive of the present invention is a method for producing a copolymer latex for an adhesive, which comprises 35 mass% or more to 75 mass% or less of an aliphatic conjugated diene monomer, 5 mass% or more to 25 mass% or less of a vinylpyridine monomer, 0 mass (A), comprising the step of emulsion-polymerizing a monomer composition (a) comprising a monomer composition (a) having a polymerization degree of 30% or more and not more than 60 mass% (B) containing 35 mass% or more and 75 mass% or less of an enumerated monomer, 5 mass% or more and 25 mass% or less of a vinylpyridine monomer, and 0 mass% or more and 60 mass% or less of another monomer copolymerizable therewith And then performing emulsion polymerization.

The method for producing a copolymer latex for an adhesive of the present invention is characterized in that the monomer composition (a) is contained in an amount of 30 mass% or more and 70 mass% or less based on the total amount of the monomer composition (a) and the monomer composition (b) , The monomer composition (b) is preferably 30 mass% or more and 70 mass% or less based on the total amount of the monomer composition (a) and the monomer composition (b).

The method for producing an adhesive copolymer latex of the present invention is characterized in that the mass% of the aliphatic conjugated diene monomer in the monomer composition (a) based on the mass% of the aliphatic conjugated diene monomer in the monomer composition (b) Of the vinylpyridine monomer in the monomer composition (a) is 0.8 or more and 1.25 or less, and the ratio of the mass% of the vinylpyridine monomer in the monomer composition (a) to the mass% of the vinylpyridine monomer in the monomer composition (b) Suitable.

According to the method for producing a copolymer latex for an adhesive of the present invention, the monomer composition (a) is subjected to emulsion polymerization, and when the polymerization conversion rate of the monomer composition (a) is 30% or more and less than 60% (B) is added to the emulsion, and the emulsion polymerization is further carried out.

Therefore, at least in the step of emulsion-polymerizing the monomer composition (a), the polymerization time can be shortened.

As a result, it is possible to secure the adhesion to the rubber reinforcing fiber of the copolymer latex for adhesive, and to improve the productivity of the copolymer latex for an adhesive.

In the method for producing a copolymer latex for an adhesive of the present invention, a monomer composition (a) (first monomer composition) comprising an aliphatic conjugated diene monomer, a vinylpyridine monomer and other monomer copolymerizable therewith is first polymerized by emulsion polymerization do.

Examples of the aliphatic conjugated diene monomer include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, And a butadiene-based monomer such as 3-butadiene.

Among these aliphatic conjugated diene monomers, a butadiene-based monomer is preferable, and 1,3-butadiene is more preferable.

These aliphatic conjugated diene monomers may be used alone (one type) or two or more types may be used in combination.

Examples of the vinylpyridine monomer include 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine and the like.

Among these vinylpyridine monomers, 2-vinylpyridine is preferable.

These vinylpyridine monomers may be used alone (one type) or two or more types may be used in combination.

Examples of the other monomers copolymerizable with the aliphatic conjugated diene monomer and the vinylpyridine monomer include aromatic vinyl monomers, cyanized vinyl monomers, ethylenically unsaturated carboxylic acid monomers, ethylenically unsaturated carboxylic acid alkyl ester monomers, Unsaturated monomers, and ethylenically unsaturated carboxylic acid amide monomers.

Examples of the aromatic vinyl monomers include styrene,? -Methylstyrene, monochlorostyrene, and the like.

Examples of the cyanoized vinyl monomers include acrylonitrile and methacrylonitrile.

Examples of the ethylenically unsaturated carboxylic acid monomer include ethylenically unsaturated monocarboxylic acid monomers such as acrylic acid, methacrylic acid and crotonic acid, and ethylenically unsaturated dicarboxylic acid monomers such as maleic acid, fumaric acid and itaconic acid (or anhydrides thereof) have.

Examples of the ethylenically unsaturated carboxylic acid alkyl ester monomers include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate.

Examples of the unsaturated monomer containing a hydroxyalkyl group include? -Hydroxyethyl acrylate,? -Hydroxyethyl methacrylate and the like.

Examples of the ethylenically unsaturated carboxylic acid amide monomer include acrylamide and methacrylamide.

Examples of other monomers include monomers used in ordinary emulsion polymerization such as ethylene, propylene, vinyl acetate, vinyl propionate, vinyl chloride, and vinylidene chloride, in addition to the above monomers.

These other monomers may be used alone (one type) or two or more types may be used in combination.

When these monomers are used alone (one kind), aromatic vinyl monomers are preferable, and styrene is more preferable.

When two or more of these other monomers are used in combination, the combination of aromatic vinyl monomers, a combination of an aromatic vinyl monomer and a cyanized vinyl monomer, a combination of an aromatic vinyl monomer and an ethylenically unsaturated carboxylic acid monomer, an aromatic vinyl A combination of a monomer and an ethylenically unsaturated carboxylic acid alkyl ester monomer, and more preferably, a combination of styrene and? -Methylstyrene, a combination of styrene and acrylonitrile, a combination of styrene and acrylic acid, A combination of maleic acid and itaconic acid, and a combination of styrene and methyl methacrylate.

The monomer composition (a) is obtained by copolymerizing a vinylpyridine monomer with an aliphatic conjugated diene monomer in an amount of, for example, 35 mass% or more, preferably 40 mass% or more, such as 75 mass% or less, preferably 70 mass% For example, not less than 5% by mass, preferably not less than 10% by mass, such as not more than 25% by mass, preferably not more than 20% by mass, and the other monomer copolymerizable therewith as the remainder is not less than 0% By mass or more, for example, 60% by mass or less, and preferably 55% by mass or less.

If the blending ratio of the aliphatic conjugated diene monomer is less than 35% by mass, the initial adhesive force and the heat-resistant adhesive force may be lowered. When the blending ratio of the aliphatic conjugated diene monomer exceeds 75 mass%, the treated cord strength and the heat-resistant adhesive force may be lowered.

When the compounding ratio of the vinylpyridine monomer is less than 5% by mass, the initial adhesive force and the heat-resistant adhesive force may be lowered. If the blend ratio of the vinylpyridine monomer exceeds 25 mass%, the initial adhesion may be lowered.

If the blend ratio of the other monomer exceeds 60 mass%, the initial adhesive force and the heat-resistant adhesive force may be lowered.

The proportion of the monomer composition (a) relative to the total amount of the monomer composition (a) and the monomer composition (b) (described later) is 30 mass% or more, preferably 35 mass% or more, such as 70 mass% By mass is not more than 65% by mass.

When the proportion of the monomer composition (a) is within the above range, the productivity of the copolymer latex for an adhesive can be improved.

The ratio of the mass% of the aliphatic conjugated diene monomer in the monomer composition (a) to the mass% of the aliphatic conjugated diene monomer in the monomer composition (b) (described later) is, for example, 0.8 or more, preferably 0.9 or more , For example, not more than 1.25, preferably not more than 1.1.

When the proportion of the aliphatic conjugated diene monomer is within the above range, the productivity of the copolymer latex for an adhesive can be improved and the initial adhesive force can be improved.

The ratio of the mass% of the vinylpyridine monomer in the monomer composition (a) to the mass% of the vinylpyridine monomer in the monomer composition (b) (described later) is, for example, not less than 0.8, preferably not less than 0.9, , Preferably not more than 1.1.

When the ratio of the vinylpyridine monomer is within the above range, the productivity of the copolymer latex for an adhesive can be improved and the initial adhesive force can be improved.

To emulsify and polymerize the monomer composition (a), an emulsifier and a polymerization initiator are added to the monomer composition (a).

Examples of the emulsifier include nonionic surfactants such as alkylester type, alkylphenyl ether type and alkyl ether type of polyethylene glycol, such as rosin acid soap, fatty acid soap, sulfuric acid ester salt of higher alcohol, alkylbenzenesulfonic acid salt, Sulfonic acid salts, aliphatic sulfonic acid salts, aliphatic carboxylic acid salts, sulfuric acid ester salts of nonionic surfactants, and formalin condensates of naphthalene sulfonic acid salts.

These emulsifiers may be used alone (one type) or two or more types may be used in combination.

Of these emulsifiers, anionic surfactants are preferable, and rosin acid soaps, fatty acid soaps, and formalin condensates of naphthalenesulfonic acid salts are more preferable.

 The emulsifier is added to the monomer composition (a) in a proportion of, for example, 0.5 parts by mass or more, preferably 2.0 parts by mass or more, for example, 10.0 parts by mass or less, preferably 8.0 parts by mass or less based on 100 parts by mass of the monomer composition (a).

As the radical polymerization initiator, water-soluble polymerization initiators such as potassium persulfate, sodium persulfate and ammonium persulfate, for example, cumene hydroperoxide, benzoyl peroxide, t-butyl hydroperoxide, acetyl peroxide, diisopropyl Benzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, and the like.

Among these polymerization initiators, water-soluble polymerization initiators are preferably potassium persulfate, sodium persulfate and ammonium persulfate, and examples of the oil-soluble polymerization initiator include cumene hydroperoxide.

The polymerization initiator is added in a proportion of, for example, 0.05 parts by mass or more, preferably 0.1 parts by mass or more, for example, 2.0 parts by mass or less, preferably 1.0 parts by mass or less, based on 100 parts by mass of the monomer composition (a).

In order to emulsify and polymerize the monomer composition (a), a reducing agent and a chain transfer agent may be added as needed.

Examples of the reducing agent include sulfites such as sulfite, bisulfite, pyrosulfite, adithionate, dithionate, thiosulfate, formaldehyde sulfonate, benzaldehyde sulfonate such as L-ascorbic acid, erosorbic acid, And salts thereof, for example, reducing saccharides such as dextrose and saccharose, and amines such as dimethylaniline and triethanolamine.

Of these reducing agents, preferred are carboxylic acids and salts thereof, and more preferred examples thereof include L-ascorbic acid and erysorbic acid.

The reducing agent is added at a ratio of, for example, not less than 0.1 part by mass, preferably not less than 0.3 part by mass, for example, not more than 400 parts by mass, preferably not more than 350 parts by mass, based on 100 parts by mass 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, Diazomethane compounds such as dimethylzantogen disulfide and diisopropylzantogen disulfide such as tetramethyl thiuram disulfide, tetraethyl thiuram disulfide, and tetramethyl thiuram monosulfide, such as 2, Phenol compounds such as 6-di-tert-butyl-4-methylphenol and styrenated phenol, allyl compounds such as allyl alcohol, and halogenated hydrocarbon compounds such as dichloromethane, dibromomethane and carbon tetrabromide , Vinyl ethers such as? -Benzyloxystyrene,? -Benzyloxyacrylonitrile,? -Benzyloxyacrylamide, and the like, such as triphenyl ethane, pentaphenyl ethane, acrolein, meta arc Thiomalic acid, 2-ethylhexylthioglycolate, and? -Methylstyrene dimer, and the like.

These chain transfer agents may be used alone (only one), or two or more types may be used in combination.

Of these chain transfer agents, alkylmercaptan is preferable, and n-octyl mercaptan and t-dodecyl mercaptan are more preferable.

The chain transfer agent is added at a ratio of, for example, not less than 0 parts by mass, preferably not less than 0.05 parts by mass, for example, not more than 10 parts by mass, preferably not more than 7 parts by mass, per 100 parts by mass of the monomer composition (a).

In the emulsion polymerization, hydrocarbons may be added as needed.

Examples of the hydrocarbons include saturated hydrocarbons such as pentane, hexane, heptane, octane, cyclohexane and cycloheptane, and aromatic hydrocarbons such as pentene, hexene, heptene, cyclopentene, cyclohexene, cycloheptene, , And 1-methylcyclohexene, and aromatic hydrocarbons such as benzene, toluene and xylene.

The hydrocarbons are preferably cyclohexene or toluene. If the hydrocarbons are cyclohexene or toluene, they can be recovered and reused by steam distillation after completion of polymerization at a low boiling point, which is suitable from the viewpoint of environmental load.

As other additives, an electrolyte such as sodium hydroxide and sodium carbonate, a polymerization accelerator, a chelating agent and the like may be added, if necessary.

When the monomer composition (a) is polymerized in such a manner that the polymerization conversion rate (measured by the method described in Examples described later) is 30% or more, such as 60% or less, preferably 50% or less, more preferably 45% By weight.

Next, in the process for producing the copolymer latex of the present invention, when the polymerization conversion rate of the monomer composition (a) is in the above range, the monomer composition (a) is mixed with the aliphatic conjugated diene monomer, And a monomer composition (b) (second monomer composition) containing the above-mentioned other monomer are further added, followed by emulsion polymerization.

When the monomer composition (b) is added when the polymerization conversion rate of the monomer composition (a) is less than the above range (i.e., less than 30%), the monomer composition (b) It is difficult to shorten the time required for the polymerization conversion rate to become a value described later after initiation of polymerization by adding an initiator, hereinafter the same).

When the monomer composition (b) is added when the polymerization conversion rate of the monomer composition (a) exceeds the above range (i.e., 60% or more), the monomer composition (b) It may be difficult to shorten the time.

The monomer composition (b) is obtained by copolymerizing a vinylpyridine monomer with an aliphatic conjugated diene monomer in an amount of, for example, 35 mass% or more, preferably 40 mass% or more, such as 75 mass% or less, preferably 70 mass% For example, not less than 5% by mass, preferably not less than 10% by mass, such as not more than 25% by mass, preferably not more than 20% by mass, and the other monomer copolymerizable therewith as the remainder is not less than 0% By mass or more, for example, 60% by mass or less, and preferably 55% by mass or less.

If the blending ratio of the aliphatic conjugated diene monomer is less than 35% by mass, the initial adhesive force and the heat-resistant adhesive force may be lowered. When the blending ratio of the aliphatic conjugated diene monomer exceeds 75 mass%, the treated cord strength and the heat-resistant adhesive force may be lowered.

When the compounding ratio of the vinylpyridine monomer is less than 5% by mass, the initial adhesive force and the heat-resistant adhesive force may be lowered. If the blend ratio of the vinylpyridine monomer exceeds 25 mass%, the initial adhesion may be lowered.

If the blend ratio of the other monomer exceeds 60 mass%, the initial adhesive force and the heat-resistant adhesive force may be lowered.

The ratio of the monomer composition (b) to the total amount of the monomer composition (a) and the monomer composition (b) is 30 mass% or more, preferably 35 mass% or more, such as 70 mass% or less, % Or less.

When the proportion of the monomer composition (b) is within the above range, the productivity of the copolymer latex for an adhesive can be improved.

In order to emulsion-polymerize the monomer composition (b), the chain transfer agent described above may be added as needed.

The chain transfer agent is added at a ratio of, for example, not less than 0 parts by mass, preferably not less than 0.05 parts by mass, for example, not more than 10 parts by mass, preferably not more than 7 parts by mass, per 100 parts by mass of the monomer composition (b).

Then, the mixture of the monomer composition (a) and the monomer composition (b) is subjected to emulsion polymerization so that the polymerization conversion rate thereof is, for example, 90% or more.

Thereafter, for example, a polymerization inhibitor such as hydroquinone is added to stop the polymerization reaction, and unreacted monomers are removed by, for example, distillation under reduced pressure.

Thus, the copolymer latex for an adhesive of the present invention is prepared.

According to the process for producing the copolymer latex for adhesive, the monomer composition (b) is added to the monomer composition (a) when the polymerization conversion rate of the monomer composition (a) becomes 30% or more and less than 60%.

Therefore, at least in the step of emulsion-polymerizing the monomer composition (a), the polymerization time can be shortened.

As a result, it is possible to secure the adhesion to the rubber reinforcing fiber of the copolymer latex for adhesive, and to improve the productivity of the copolymer latex for an adhesive.

The obtained latex for an adhesive copolymer is preferably compounded in an adhesive composition for bonding rubber and rubber reinforcing fibers.

Examples of the rubber include, but not limited to, natural rubber, SBR, NBR, chloroprene rubber, polybutadiene rubber, polyisoprene rubber, and various modified rubbers thereof. Further, known additives such as fillers, softening agents, vulcanizing agents and vulcanization accelerators can be added to the rubber.

Examples of the rubber reinforcing fiber include nylon fiber, polyester fiber, aramid fiber and glass fiber. The form of these fibers is not particularly limited, and examples thereof include cord, cable, fabric, canvas, and short fiber.

The adhesive composition is obtained by mixing and mixing a copolymer latex for an adhesive with a resorcinol-formalin resin.

In order to prepare the adhesive composition, the copolymer latex for adhesive and the resorcinol-formalin resin are not particularly limited, but a resorcinol-formalin resin may be added to 100 parts by mass (solids content) of the copolymer latex for an adhesive, Such as not more than 100 parts by mass, preferably not more than 90 parts by mass.

The adhesive composition may further contain, if necessary, an isocyanate, a block isocyanate, an ethylene urea, 2,6-bis (2,4-dihydroxyphenylmethyl) -4-chlorophenol, A condensation product of resorcin and a mixture of resorcin-formalin condensate and the like, an adhesion improvers such as polyepoxide, modified polyvinyl chloride, and carbon black, fillers, crosslinking agents, vulcanizing agents, vulcanization Accelerators, and the like.

In order to bond the rubber and the rubber reinforcing fiber, the adhesive composition is first treated with the rubber reinforcing fiber.

In order to treat the adhesive composition with the rubber reinforcing fiber, the rubber reinforcing fiber is immersed in the adhesive composition, for example, by using a dipping machine or the like. For example, 80 seconds or more, preferably 100 seconds or more, such as 200 seconds or less, preferably 150 seconds or less, for example, 100 占 폚 or more, preferably 110 占 폚 or more, For example 30 seconds or more, preferably 50 seconds or more, such as 100 seconds or less, for example, at 180 占 폚 or higher, preferably 200 占 폚 or higher, such as 300 占 폚 or lower, Preferably 80 seconds or less.

After the above treatment, 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 pressed, whereby the rubber and the rubber reinforcing fiber are bonded.

Example

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples. On the other hand, in the examples, parts and% indicating the mixing ratio are based on a mass basis.

1. Synthesis of copolymer latex

(1) Example 1

130 parts of water, 1 part of sodium naphthalenesulfonate-formalin condensate, 0.1 part of sodium hydroxide and 5.0 parts of potassium rosinate were dissolved in an autoclave equipped with a stirrer.

Then, the monomer composition (a) shown in Table 1 and 0.3 part of t-dodecyl mercaptan were added and emulsified.

Subsequently, 0.5 parts of potassium persulfate was added and the inner temperature was maintained at 60 占 폚 to polymerize the monomer composition (a).

When the polymerization conversion rate of the monomer composition (a) reached the polymerization conversion rate shown in Table 1, the monomer composition (b) shown in Table 1 and 0.35 part of t-dodecyl mercaptan were added and the polymerization was continued.

When the polymerization conversion rate reached 93%, 0.1 part of hydroquinone was added to terminate the polymerization, and thereafter the unreacted monomers were removed by distillation under reduced pressure to obtain a copolymer latex. Table 1 shows the time (polymerization time) from the addition of potassium persulfate to the addition of hydroquinone.

(2) Examples 2 and 3

Except that the monomer composition (a) shown in Table 1 was polymerized until the polymerization conversion rate as shown in Table 1 was reached, and then the monomer composition (b) shown in Table 1 was added and the polymerization was continued. , A copolymer latex was obtained. The polymerization time is shown in Table 1.

(3) Example 4

100 parts of water, 1 part of sodium naphthalenesulfonate-formalin condensate, 0.1 part of sodium hydroxide and 4.0 parts of potassium rosinate were dissolved in an autoclave equipped with a stirrer.

Then, the monomer composition (a) shown in Table 1 and 0.2 part of t-dodecyl mercaptan were added and emulsified.

Subsequently, 0.5 parts of potassium persulfate was added and the inner temperature was maintained at 60 占 폚 to polymerize the monomer composition (a).

When the polymerization conversion rate of the monomer composition (a) reached the polymerization conversion rate shown in Table 1, the monomer composition (b) shown in Table 1 and 0.3 part of t-dodecyl mercaptan were added and then polymerized.

When the polymerization conversion rate reached 93%, 0.1 part of hydroquinone was added to terminate the polymerization, and thereafter the unreacted monomers were removed by distillation under reduced pressure to obtain a copolymer latex. The polymerization time is shown in Table 1.

(4) Comparative Example 1

130 parts of water, 1 part of sodium naphthalenesulfonate-formalin condensate, 0.1 part of sodium hydroxide and 5.0 parts of potassium rosinate were dissolved in an autoclave equipped with a stirrer.

Subsequently, the monomer composition (a) shown in Table 2 and 0.6 part of t-dodecyl mercaptan were added and emulsified.

Subsequently, 0.5 part of potassium persulfate was added and the inner temperature was maintained at 50 占 폚 to polymerize the monomer composition (a).

When the polymerization conversion rate reached 93%, 0.1 part of hydroquinone was added to terminate the polymerization, and thereafter the unreacted monomers were removed by distillation under reduced pressure to obtain a copolymer latex. The polymerization time is shown in Table 2.

(5) Comparative Examples 2 to 5

Except that the monomer composition (a) shown in Table 2 was polymerized until the polymerization conversion rate as shown in Table 2 was reached, and then the monomer composition (b) shown in Table 2 was added and the polymerization was continued. , A copolymer latex was obtained. The polymerization time is shown in Table 2.

2. Evaluation of physical properties of copolymer latex

(1) Method of measuring polymerization conversion rate

Approximately 2 g of the copolymer latex sampled during the polymerization is weighed, and this value is referred to as " weight before drying ". This is dried at 150 캜 for 30 minutes and weighed, and this value is referred to as " weight after drying ". The number of solid components other than monomers to be charged into the polymerization vessel is defined as S and the sum of S, the number of polymerized water (water) and the total number of monomers is set to be the total number of charged units, 2), the polymerization conversion rate is calculated by the formula (3).

Equation (1)   Polymerization number of rings = total number of injections x weight after drying / weight before drying -S

Equation (2)   Total monomer = total number of additions - (number of polymerization water + S)

Formula (3) Polymerization Conversion Rate = Polymerization Number of Copies / Number of Monomers Total 100

(2) Measurement of average particle size by photolithographic method of copolymer latex

The average particle size of the copolymer latex by photon correlation was measured by a dynamic light scattering method. On the other hand, in the measurement, FPAR-1000 (manufactured by Otsuka Electronics Co., Ltd.) was used (JIS Z8826). The results are shown in Tables 1 and 2.

(3) Mooney viscosity

The copolymer latexes of the respective examples and comparative examples were dried and the Mooney viscosity (ML1 + 4, 100 占 폚) of the obtained solid content (resin component) was measured according to JIS K6300. The results are shown in Tables 1 and 2.

(4) Glass transition temperature

0.5 g of the copolymer latex of each of the Examples and Comparative Examples was applied to a glass plate and dried at 70 DEG C for 4 hours to produce a film.

The resulting film was placed in an aluminum pan of a differential scanning calorimeter (DSC) and cooled to -100 ° C at 10 ° C / min.

Subsequently, the temperature was raised from -100 DEG C to 150 DEG C at a rate of 10 DEG C / min, and the start point of the endotherm of the phase change was read to obtain the glass transition temperature (DEG C). The results are shown in Tables 1 and 2.

3. Preparation of adhesive composition

To 239 parts of water, 0.3 part of sodium hydroxide was added and stirred. Then 11 parts of resorcin and 16.2 parts of 37% formalin were added to the mixture, followed by stirring and aging at 25 캜 for 6 hours to synthesize a resorcinol-formalin resin.

Then, the total amount of the obtained resorcin-formalin resin and 12.6 parts of 28% ammonia water was added to the copolymer latex obtained in each of the Examples and Comparative Examples, and the resulting mixture was stirred. Then, water was added , The solid concentration was adjusted to 20 mass% and aged at 25 占 폚 for 18 hours to obtain an adhesive composition.

4. Evaluation of Adhesion of Adhesive Composition

(1) Tire cord immersion treatment

The pre-treated nylon tire cord 1260D / 3 was immersed in each of the obtained adhesive compositions using a single cord type dipping machine for testing, dried at 120 DEG C for 120 seconds, and then baked at 200 DEG C for 60 seconds.

(2) Rubber

The rubber was prepared by the following formulation.

<Rubber formula>

caoutchouc 70 parts

SBR rubber 30 copies

FEF Carbon 40 copies

Process oil Part 4

Antigen RD (* 1) Part 2

Stearic acid 1.5 parts

Zinc oxidation Part 5

Vulcanization accelerator DM (* 2) 0.9 part

sulfur 2.7

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

* 2: Dibenzothiazide disulfide

(2) Measurement of initial adhesion force

The nylon tire cords treated with the adhesive compositions of the respective examples and comparative examples were sandwiched with rubber and vulcanized and pressed at 140 DEG C for 45 minutes.

The initial adhesion of rubber and rubber reinforced fibers was measured according to ASTM D2138-67 (H Pull Test). The results are shown in Tables 1 and 2.

While the invention has been described as an exemplary embodiment of the invention, it is to be understood that the invention is by way of example only and is not to be construed in a limiting sense. Variations of the invention that are evident to one skilled in the art are included in the claims below.

The method for producing a copolymer latex for an adhesive of the present invention is used, for example, to produce a copolymer latex for an adhesive compounded with an adhesive composition for bonding rubber and rubber reinforcing fibers.

Claims (3)

(A) comprising at least 35 mass% and not more than 75 mass% of an aliphatic conjugated diene monomer, not less than 5 mass% and not more than 25 mass% of a vinylpyridine monomer, and 0 mass% or more and 60 mass% or less of other monomers copolymerizable therewith );
When the polymerization conversion rate of the monomer composition (a) is 30% or more and less than 60%, the monomer composition (a) contains 35% by mass or more and 75% by mass or less of the aliphatic conjugated diene monomer, 5% By mass of a monomer composition (b) containing 0% by mass or more and 60% by mass or less of other monomers copolymerizable therewith and emulsion polymerization
Wherein the copolymer latex is a copolymer latex. The method according to claim 1,
The monomer composition (a) is 30 mass% or more and 70 mass% or less based on the total amount of the monomer composition (a) and the monomer composition (b)
The monomer composition (b) is added in an amount of 30% by mass or more and 70% by mass or less based on the total amount of the monomer composition (a) and the monomer composition (b)
&Lt; / RTI &gt; wherein the copolymer latex is a copolymer latex. 3. The method according to claim 1 or 2,
The ratio of the mass% of the aliphatic conjugated diene monomer in the monomer composition (a) to the mass% of the aliphatic conjugated diene monomer in the monomer composition (b) is 0.8 or more and 1.25 or less,
The ratio of the mass% of the vinylpyridine monomer in the monomer composition (a) to the mass% of the vinylpyridine monomer in the monomer composition (b) is 0.8 to 1.25
&Lt; / RTI &gt; wherein the copolymer latex is a copolymer latex.