JPS6022030B2 - Adhesion method between fiber materials and rubber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of bonding textile materials and rubber.

There are many uses for rubber, such as tires, belts, and waterproof sheets, where adhesion between reinforcing fibers and rubber is important.

For bonding fibers with natural rubber (hereinafter abbreviated as NR), styrene-butadiene copolymer rubber (hereinafter abbreviated as SBR), etc., resorcin formaldehyde resin aqueous liquid and N are used.
Compositions with R latex, SBR latex, or terpolymer rubber latex of styrene, butadiene, and vinylpyridine are used as so-called RFL adhesives.

However, terpolymer rubber (hereinafter abbreviated as EPDM) consisting of ethylene, a Q-olefin higher than ethylene, and a non-conjugated diolefin has been mainly used in tires and belts because of its weather resistance, ozone resistance, heat resistance, etc. Although it is far superior to highly unsaturated rubbers such as NR and SBR, it has poor adhesion to fibers and sufficient adhesive strength cannot be obtained even when using the above RFL adhesive. Therefore, its uses are limited. In addition, inbutylene isoprene copolymer rubber (butyl rubber - hereinafter abbreviated as 11R) has similar circumstances.

Therefore, the present inventors conducted intensive studies on bonding methods between EPDM and other fibers, and found that an organic solvent solution of a resorcinol formaldehyde resin aqueous liquid (hereinafter abbreviated as RF liquid) and a sulfohalogenated polymer (hereinafter abbreviated as SHP) They also discovered that an excellent adhesive effect could be obtained by using an aqueous dispersion in combination, and filed a patent application.

(Japanese Patent Application No. 55-180822) Furthermore, we continued to study this adhesive method, especially the adhesive method using SHP water dispersion, and found that the adhesive strength was significantly improved by using polyvinyl alcohol in combination, and we obtained a patent for this as well. I applied. (Patent application No. 56-62847) These polyvinyl alcohols can be used in combination with rubbers such as NR and SBR, and SH.
It is also effective in adhering P and fibers. As a result of further various studies, the present inventors discovered that the adhesive strength could be further improved by using sulfohalogenated polyethylene (hereinafter abbreviated as SHPE) made from high-density polyethylene as the sulfohalogenated polymer. It's arrived.

In the method of the present invention, fibers are usually first impregnated with an RF liquid by an appropriate method such as dipping, coating, spraying, or rolling.
Resorcinol can be used as is, or if necessary, can be treated with resorcinol through appropriate drying, heat treatment, or other processes. Fibers treated with formaldehyde resin are impregnated with an aqueous SHPE dispersion containing polyvinyl alcohol by an appropriate method such as bonding, coating, spraying, or roll treatment, and then subjected to processes such as drying and heat treatment to remove various additives. A method of contact vulcanization treatment with rubber such as EPDM mixed with an agent, or a method of vulcanizing a composition prepared by mixing RF liquid, SHPE water dispersion, and polyvinyl alcohol in an appropriate manner such as bonding, coating, spraying, or roll treatment. After impregnating the fibers, the rubber such as EPDM and fibers are strengthened by contact vulcanization treatment with rubber such as EPDM mixed with various additives through processes such as drying and heat treatment. It is to be attached to.

Among these methods, the method of treating fibers using a composition in which RF liquid, SHPE aqueous dispersion, and polyvinyl alcohol are mixed in advance is industrially advantageous because the process is simplified; The composition is an excellent adhesive composition.

The SHPE used in the present invention is made from high-density polyethylene having a density of 0.94 m/s or more and is sulfohalogenated. Of course, most of the polymer constituent units are ethylene, and as long as the density satisfies the above value, it is natural that sulfohalides containing small amounts of other units, such as propylene or butylene units, can be used. . Chlorine and bromine are commonly used as halogens. For example, when bonding EPDM or 11R to fibers, sulfochloride of polyethylene is usually used.
In this case, the chlorine content is from 5 to 7% by weight, preferably 10% by weight.
-5% by weight, more preferably 18-45% by weight, with a sulfur content of 0.1-10% by weight, preferably 0.2-3% by weight, even more preferably 0.5-2.5% by weight. is often used. Regarding the amount of halogen in SHPE, there is an appropriate range from the viewpoint of adhesive strength, and if it is too small or too large, sufficient adhesive strength may not be obtained.

Regarding the sulfur content, if it is too small, it is difficult to obtain the desired adhesive strength, and if it exceeds a certain amount, thermal stability generally decreases.

The aqueous dispersion of SHPE can be obtained by sulfohalogenating an aqueous dispersion of raw material polyethylene, by dispersing SHPE in water, and the latter method is usually adopted.

That is, a dispersion consisting of a SHPE solution phase and an aqueous phase is prepared by mixing the SHPE solution with water containing an appropriate emulsifier using a method such as high-speed rope heating, and then heated under an appropriate pressure such as pressurized, normal pressure, or reduced pressure. Then, some or all of the solvent is removed from the solution phase by vaporizing distillation, etc., and if necessary, some of the water is removed by vaporizing distillation or by using centrifugal force. The method described above is used to adjust the concentration to an appropriate concentration of about 5% to 7% by weight. In this case, the SHPE solution includes aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene, and halogenated carbonates such as carbon tetrachloride, ethylene tetrachloride, ethane tetrachloride, and various fluorinated chlorinated hydrocarbons. Hydrogen solutions are often used, especially c.

It is advantageous to use the product of the sulfohalogenation reaction in the hydrogenated hydrocarbon as it is. In the SHPE aqueous dispersion, an emulsifier is usually used as a dispersion stabilizing agent, as shown in the above production method.

These emulsifiers include fatty acid soaps, rosin acid soaps, alkyl ether sulfonates, alkyl sulfonates, alkyl sulfates, alkenesulfonates, alkyl ether sulfonates, dialkyl sulfosuccinates, polyoxy tyrene alkyl ethers, polyoxyethylene alkyl esters, polyoxyethylene alkyl allyl ethers, polyoxyethylene alkyl allyl esters, fatty acid sucrose esters, naphthalene sulfonic acid soda formalin condensate, Various anionic surfactants, nonionic surfactants, cationic surfactants, and amphoteric surfactants, such as tetraalkylammonium salts, alkylpyridinium salts, alkylbenzylammonium salts, polyethylene polyamine tetraacetic acid salts, alkylbetaines, etc. Among these, anionic surfactants are generally preferred from the viewpoint of adhesive strength, and in particular, anionic surfactants such as stearic acid, palmitic acid, myristic acid, lauric acid, oleic acid, rosin acid, etc. such as sodium and potassium surfactants are used. Emulsifiers containing alkali metal salts and carboxylic acid alkali metal salts in their molecules, such as so-called beef tallow soap and bamboo shoot oil soap, are excellent. Naturally, a mixture of these emulsifiers is used, and methods such as using a carboxylic acid alkali metal salt type emulsifier as the main emulsifier and adding a small amount of a nonionic type emulsifier to improve stability are also used. These emulsifiers are SHPE
Generally 0.01 to 20% by weight, preferably 0.1% by weight
~1% by weight is used.

o. If it is less than 0.01%, the dispersion stabilizing effect will not be sufficient, and even if it is used in excess of 20%, the effect will be almost the same as in the case of 20%. It is also possible to use a small amount of a milk additive such as isoprobanol, which is soluble in both water and an organic solvent, for this water content calculation.

The RF liquid used in the present invention is generally a product obtained by reacting a substance that easily generates formaldehyde such as formaldehyde or paraformaldehyde with a phenolic compound such as dihydroxybenzenes such as zorcin by an appropriate known method. do. For 1 mole of phenolic compound, 0.5 mole of formaldehyde was added under various pH conditions such as basic conditions of pH 8 to 9 in the presence of alkali metal hydroxide and acidic conditions such as pH 3 to 4.
The reaction is carried out under the following conditions at room temperature or under heating, and neutralization is carried out at the end of the reaction if necessary. Further, if necessary, the concentration is adjusted to an appropriate concentration such as 5% by weight or 40% by weight. The polyvinyl alcohol used in the present invention is a polymer whose main structural unit is a homopolymer of vinyl acetate or a completely saponified product or a partially saponified product of a copolymer of vinyl acetate with other monomers. It is a combination of completely saponified polyvinyl acetate or partially saponified polyvinyl acetate.

Polyvinyl alcohol is usually mixed in advance with the SHPE aqueous dispersion before use.

In this case, there are many advantages such as increasing the stability of the SHPE water extract. Of course, it is also possible to use it by mixing it with RF liquid or RFL liquid. Polyvinyl alcohol is usually water-repellent and dissolves at least in hot water, so it must be dissolved or dispersed in water in advance and used in SHPE.
Although it is often mixed in a predetermined amount with an aqueous dispersion or the like, it may be advantageous in some cases to directly dissolve or disperse solid polyvinyl alcohol in an aqueous SHPE dispersion or the like.

The composition of the RF liquid, SHPE aqueous dispersion and polyvinyl alcohol used in the present invention is usually prepared by mixing the RF liquid with a SHPE aqueous dispersion mixed with polyvinyl alcohol, or by mixing the RF liquid and the SHPE aqueous dispersion, and then This system is prepared by mixing an aqueous solution or an aqueous dispersion of polyvinyl alcohol, particularly polypynyl alcohol, and adjusting the concentration to 5 to 6% solids by weight, if necessary.

Of course, after reacting formaldehyde etc. with a phenolic compound in the SHPE water dispersion, polypynyl alcohol or polyvinyl alcohol is added.
In many cases, it is possible to produce the adhesive by reacting formaldehyde or the like with a phenolic compound in an HPE aqueous dispersion, but this usually tends to cause problems such as the reproducibility of adhesive strength. In the present invention, the amount of SHPEIO is 500% by weight, preferably 500% by weight, based on the solid content in the RF liquid.
Often 0-200% by weight is used.

In addition, polyvinyl alcohol is 0.1 to SHPE
3% by weight, preferably 0.3 to 1% by weight is often used. Note that various auxiliary agents such as viscosity modifiers and antioxidants may be added to the RF liquid, SHPE aqueous dispersion, and compositions consisting of the RF liquid, SHPE aqueous dispersion, and polyvinyl alcohol used in the present invention. In the method of the present invention, which can naturally be used, after impregnating fibers with an RF liquid,
If necessary, S is dried and heat-treated at an appropriate temperature such as room temperature to 20 psi, and further polyvinyl alcohol is added.
After impregnating with HPE water dispersion and drying and heat-treating at an appropriate temperature such as room temperature to 200 qo, or after adding RF liquid and polyvinyl alcohol to fibers.
After mixing the HPE aqueous dispersion sequentially or in advance, impregnating it, drying and heat-treating it at an appropriate temperature such as room temperature to 200°C, and then mixing a vulcanizing agent, a vulcanization accelerator, an anti-aging agent, a reinforcing agent, etc. For example, by laminating rubber with a suitable vulcanization compound, etc., or vulcanizing it under normal vulcanization conditions, such as under pressure of 130 to 160 qo for several minutes to 2 hours, etc. The bond is completed by adding a rubber finishing treatment.

Note that any amount of adhesive can be used, but for example, RF
The total amount of liquid-solid content and SHPE is usually 3 to 3% by weight based on the fiber. The method of the present invention includes NR, isoprene rubber, SBR, butadiene rubber, acrylonitrile butadiene rubber, 11R, EPDM, ethylene propylene copolymer rubber, sulfochlorinated polyethylene rubber (
(hereinafter abbreviated as CSM) ethylene propylene diene copolymer rubber, imbutylene isof. Various rubbers such as ethylene copolymer rubber, ethylene propylene butene copolymer rubber, ethylene butene copolymer rubber, ethylene propylene butene copolymer rubber, ethylene butene copolymer rubber, cotton, rayon, acetate, nylon, aromatic polyamide , various fibers such as polyester, vinylon, acrylic, polypropylene, especially EPDM, ethylene propylene rubber,
It is effective for bonding rubbers such as 11R, chlorosulfonated polyethylene rubber and fibers such as cotton, rayon, nylon, aromatic polyamide, polyester, and vinylon.
Of course, the above-mentioned fibrous material includes not only fibrous materials in the narrow sense but also woven materials such as cloth. The method of the present invention is also effective for bonding sheets or molded products made of the above-mentioned fiber materials to the above-mentioned rubber. Also, CSM
C, such as using a mixture of and various rubbers as rubbers.
Good results are often obtained by using SM together, and the effect is particularly remarkable in the case of EPDM and 11R. Furthermore, in the method of the present invention, NR latex, S
It is of course possible to use latices such as BR latex or styrene-butadiene-vinylpyridine terpolymer latex and conventional RFL adhesives in combination in any desired manner, often with good results.

The present invention will be explained in more detail with reference to Examples below.

Example 1 .

Sulhok. Preparation of sulfochlorinated polyethylene latex (CSM latex) 40 days of sulfochlorinated polyethylene (chlorine content 25%, sulfur content 1%) produced from high-density polyethylene (density 0.96 days/lump) was dissolved in 370 days of toluene. .

A 25% aqueous solution of potassium rosin acid (4.8%) diluted with water to 370% was mixed with the above toluene solution, and emulsified for 20 minutes using a high-speed rope frame machine. Pour this emulsion into a 2-inch glass flask equipped with a thermometer, a Hakiyo machine, and a condenser.
The contents were concentrated to 1.31 ml by heating in a 70° Hg water bath under reduced pressure to remove the toluene and then remove the water. A white latex with a rubber content of 30.5% was obtained by this method. o Addition of polyvinyl alcohol Polyvinyl alcohol (manufactured by Kuraray Co., Ltd., trade name: Poval PVA-217, average degree of polymerization 1750, degree of saponification 88 mol%) was dissolved in 190 mol% of water and the above latex 131 was added. Added 40 nights of fly dropping.

The amount of polyvinyl alcohol used is 5% by weight of the sulfochlorinated polyethylene. o Preparation of RF liquid A solution prepared by dissolving 0.4 parts of caustic soda in 242 parts of water was mixed with 11 parts of resorcinol and 16.2 parts of a 37% formalin aqueous solution, and left at room temperature for 5 hours to age.

o Preparation of RFL liquid 27.5 hours of the CSM latex containing polyvinyl alcohol and 20 hours of RF liquid were mixed and left to age at room temperature for 2 hours.

The ratio of solids in the RF fluid/SHPE in the CSM latex is 1/5. o Adhesive rubber compound EPDM*E502 7 Anchor part EPDM*E51 Bait 3 Zinc oxide 5 parts Stearic acid 1 part Sail or Bon
1 Sea bream Diana Process NM280 7 Anchor capital N
-Cyclohexyl-2-penzothiazylsulfenamide 1.5 parts Tetramethylthiuram disulfide 0.5 parts Dibentamethylenethiuram tetrasulfide 0.7 parts Zinc dibutyldiocarbamate 1.5 parts Sulfur 1
Department* Sumitomo Chemical ■. Esprene (ethylene propylene ethylidene norponene ternary copolymer rubber) o Measurement of adhesion strength A 1260 denier nylon cord was immersed in the above RFL liquid, and then dried and baked in a constant temperature dryer at 150 q0 for 3 minutes. .

The treated cord thus prepared was embedded in the unvulcanized adhered rubber compound described above and vulcanized at 15,000 for 30 minutes to prepare an H-test specimen.
The adhesive strength was measured by the "H-pull test" described in rld Vol. 114, pages 213-217 (1946), and it was found to be 9.5k9.
/9 ribs was obtained.

Also, almost the same adhesive strength was obtained when Kepler fiber (aromatic polyamide fiber manufactured by DuPont) was used instead of the nylon cord. Comparative Example 1 The same adhesion test as in Example 1 was conducted except that CSM Latex 21.1, which does not contain polyvinyl alcohol, was used in preparing the RFL liquid in Example 1. The results were as follows: 5.2/9 willow with nylon cord. The adhesive strength was .

Comparative Example 2 In the preparation of the RFL liquid in Example 1, animal gelatin, glue, casein, vegetable gum tragacanth, gum arabic, sodium alginate, and starch, which are generally known as thickeners or stabilizers, were used instead of polyvinyl alcohol. We conducted adhesion tests using inorganic silica colloids, bentonite clay, synthetic cellulose derivatives such as methylcellulose and carboxymethylcellulose, polyacrylates, polyacrylamide, and polyethylene oxide, but no significant increase in adhesive strength was found. was not recognized.

Example 2 Adhesion was carried out in the same manner as in Example 1, except that sulfochlorinated polyethylene (chlorine content 35%, sulfur content 1.2%) manufactured from high-density polyethylene (density 0.955 m/g) was used. The results of the test showed that the adhesive strength was almost the same as in Example 1.

Comparative Example 3 High-density polyethylene of Example 1 (density 0.96 m/ground)
Instead of low density polyethylene (density ~.93 y/s)
Sulfochlorinated polyethylene (chlorine content 2
A latex was produced in the same manner as in Example 1, except that a sulfur content of 9% and a sulfur content of 1% was used.

The same adhesion test as in Example 1 was performed and the result was 7.8k9/
The adhesive strength was on the 9th side.

Claims (1)

[Claims] 1 Resoncin formaldehyde resin aqueous liquid, density is 0
．． A method for adhering textile materials and rubber, characterized by using a sulfohalogenated polyethylene aqueous dispersion made from high-density polyethylene exceeding 94 g/cm^3 and polyvinyl alcohol. 2. The method according to claim 1, wherein the fiber material is fibrous or woven. 3 Rubbers are ethylene propylene diene copolymer rubber, ethylene propylene copolymer rubber, isobutylene isoprene copolymer rubber, chlorosulfonated polyethylene rubber, ethylene propylene butene copolymer rubber, ethylene propylene butene diene copolymer rubber, ethylene butene copolymer rubber ,
The method according to claim 1, which is ethylene butenediene copolymer rubber or a mixture thereof. 4. The method according to claim 1, wherein the sulfohalogenated polyethylene made from high-density polyethylene having a density exceeding 0.94 g/cm^3 is sulfochlorinated polyethylene. 5. The method according to claim 1, wherein a carboxylic acid is used as an emulsifier in an aqueous dispersion of sulfohalogenated polyethylene made from high-density polyethylene having a density exceeding 0.94 g/cm^3. 6 The degree of polymerization of polyvinyl alcohol is 400 to 3000
The method according to claim 1, wherein the degree of saponification is 75 to 100 mol%.