JPH0611942B2 - Adhesion method between polyester fiber and rubber - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for adhering polyester fiber and rubber.

(Prior Art) Conventionally, in order to bond a polyester fiber and a rubber, the fiber is immersed in an aqueous dispersion mainly composed of a resorcinol-formaldehyde resin and a latex and used. The latex is butadiene-vinyl pyridine-
A styrene copolymer latex or a mixed latex of the styrene copolymer latex and a styrene-butadiene copolymer latex or a natural rubber latex is generally used.

Polyester fiber is widely used as a fiber for rubber reinforcement in automobile tires, belts, hoses, etc. due to its low elongation, but its use is restricted because the fiber deteriorates significantly depending on the conditions of use. Is receiving. That is, when the rubber of the molded product contains a vulcanization accelerator such as thiuram-based, sulfenamide-based, or guanidine-based vulcanization accelerator, an amine-based antiaging agent, or natural rubber, it is added for a long period of time, for example, when manufacturing an automobile tire. This is because the polyester fiber is deteriorated during the vulcanization step or during the high-speed running of the automobile tire, and the performance as the reinforcing fiber is significantly deteriorated.

In order to ameliorate this drawback, improvement by a rubber compounding method by selecting a preferable vulcanization accelerator, antioxidant, etc.,
Improvement of the polyester fiber itself by reducing the amount of terminal carboxyl groups contained in the polyester fiber, or a method of treating the polyester fiber with a compound containing a carboxyl group in advance (for example, JP-A-55-166235) has been devised. However, with the method, the compounding of rubber is restricted and the desired vulcanized rubber physical properties cannot be obtained, and at the same time, the adhesive strength between rubber and fiber after long-term vulcanization (hereinafter referred to as heat resistant adhesive strength) is not sufficiently improved. By the method of and, the thermal deterioration of the fiber itself is improved, but the heat resistant adhesive strength is not improved. The inventors of the present invention have conducted extensive studies to develop an improved polymer latex used for bonding fibers and rubber based on the finding that, when a latex having a pyridyl group and a carboxyl group is used in the copolymer, Amazingly,
It was found that the heat-resistant adhesive strength of the polyester fiber, which cannot be obtained by the combined use of the conventional adhesives of the above method, can be improved.

As a result of further studies, by treating the polyester fiber with the above latex first and then treating with the vinylpyridine-containing polymer latex conventionally used, it is possible to suppress the decrease in the strength of the fiber due to heat and also the heat resistant adhesive strength with rubber. The inventors have found that they are significantly improved and have completed the present invention.

(Problems to be Solved by the Invention) An object of the present invention is to provide a heat-resistant adhesive force between a fiber and rubber when polyester fiber is used as a reinforcing material for a rubber product such as a tire, a belt and a rubber hose, and a heat-resistant strength of the fiber. It is an object of the present invention to provide a method for adhering a polyester fiber and rubber, which improves

(Means for Solving the Problems) The object of the present invention is to first bond (1) the resorcinol-formaldehyde resin (a) and the conjugated diene monomer 35 to 35 when vulcanizing and adhering the polyester fiber and the rubber. 75 wt%, ethylenically unsaturated acid monomer 0.5 to 25 wt%,
Treated with a composition consisting of 15 to 45% by weight of vinyl pyridine and 0 to 40% by weight of another monomer and 0 to 40% by weight of another monomer copolymerizable therewith, and then (2). Resorcinol-formaldehyde resin (a), conjugated diene monomer 45 to 95% by weight, vinyl pyridine 5
To 35% by weight and 0 to 30% by weight of other monomers excluding the ethylenically unsaturated acid monomer copolymerizable with these monomers, and a copolymer rubber latex (c). This is accomplished by using treated polyester fibers.

As described above, the characteristic feature of the present invention resides in the use of the polyester fiber which is first treated with the composition containing the copolymer rubber latex (b) and then treated with the composition containing the copolymer latex (c).

The copolymer latex (b) used in the present invention is used for improving the heat resistance strength of the polyester fiber. The copolymer latex (b) is obtained by emulsion copolymerizing the following monomers.

Examples of the conjugated diene monomer include aliphatic conjugated diene-based monomers such as 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, and halogen-substituted butadiene. 1 type (s) or 2 or more types are used.

The content of the conjugated diene monomer in the copolymer rubber composing the copolymer rubber latex (b) is usually 35 to 75% by weight.
However, if it deviates from this range, the polyester fiber treated with the adhesive will be too hard. It is preferably 45 to 75% by weight.

2-Vinylpyridine is preferable as vinylpyridine, but one or more of 3-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, 5-ethyl-2-vinylpyridine, etc. should be substituted. You can

The content of the vinyl pyridine monomer in the copolymer rubber is usually 15 to 45% by weight, and if the content is out of this range, the heat-resistant adhesive strength is lowered. It is preferably 20 to 40% by weight, and more preferably 20 to 35% by weight.

Ethylenically unsaturated acid monomers include acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, itaconic acid, fumaric acid, maleic acid, butenetricarboxylic acid and other unsaturated carboxylic acids; itaconic acid monoethyl ester, fumaric acid Monoalkyl ester of unsaturated dicarboxylic acid such as monobutyl ester and maleic acid monobutyl ester; 1 such as unsaturated sulfonic acid such as sulfoethyl Na salt of acrylic acid, sulfopropyl Na salt of methacrylic acid and acrylamidopropanesulfonic acid or its alkali salt Seed or 2
More than one seed is used. The carboxyl group may be introduced into the latex by copolymerizing an ethylenically unsaturated acid ester monomer or an ethylenically unsaturated acid anhydride monomer and then hydrolyzing it. Examples of ethylenically unsaturated acid ester monomers and ethylenically unsaturated acid anhydride monomers include acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, itaconic acid, fumaric acid, maleic acid and butenetricarboxylic acid. Examples thereof include saturated carboxylic acid mono-, di-, and triesters and maleic anhydride, and one or more of these are used.

The content of the ethylenically unsaturated acid monomer in the copolymer rubber is usually 0.5 to 25% by weight. Below this, the heat-resistant adhesive strength becomes low, and above this, the initial adhesive strength becomes low.
It is preferably 1 to 8% by weight, more preferably 1 to
6% by weight. Further, if desired, another monomer copolymerizable with each of the above monomers can be copolymerized. Examples of such a monomer include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene and 4-methylstyrene.
Methyl styrene, 2,4-diisopropyl styrene,
2,4-dimethylstyrene, 4-t-butylstyrene,
Aromatic vinyl compounds such as 5-t-butyl-2-methylstyrene, monochlorostyrene, dichlorocytylene, monofluorostyrene and hydroxymethylstyrene, and esters of unsaturated monocarboxylic acids such as methyl acrylate, ethyl acrylate, and metimemethacrylate. And aliphatic vinyl compounds such as ethylene, propylene, acrylonitrile and vinyl chloride are exemplified.
One kind or two or more kinds can be copolymerized. The content of the copolymer rubber is 40% by weight or less.

The method for producing the latex of the present invention is not particularly limited, and all the monomers to be used may be batch-charged into a polymerization vessel to be produced by one-step polymerization, or after the polymerization of a part of the monomers, the remaining It may be produced by a two-step polymerization method or the like in which the above monomer is added to continue the polymerization.

The copolymer rubber latex (c) used in the present invention is used together with the copolymer rubber latex (b) to improve the heat-resistant adhesive strength between the polyester fiber and the rubber, but in the case of the copolymer rubber latex (b) The same conjugated diene monomer,
It can be obtained by copolymerizing vinyl pyridine and, if necessary, other monomers other than the ethylenically unsaturated acid monomer copolymerizable therewith by ordinary emulsion polymerization.

The conjugated diene monomer is 45 to 95% by weight in the copolymer rubber constituting the copolymer rubber latex (C), the vinyl pyridine is 5 to 35% by weight, and the other monomer copolymerizable with these is 0 to 50% by weight. ~ 30% by weight.

As the other copolymerizable monomer, the same aromatic vinyl compound, aliphatic vinyl compound, methyl acrylate as described above,
Examples thereof include esters of unsaturated monocarboxylic acids such as ethyl acrylate and methyl methacrylate, and one or more of these are copolymerized as necessary.

As the copolymer rubber latex (c), a conventionally used butadiene / styrene / 2-vinylpyridine copolymer rubber latex is preferably used.

The resorcinol-formaldehyde resin used in the present invention is the resin used conventionally (for example, JP-A-55-14263).
No. 5, etc.) can be used without any particular limitation.
In addition, 2,6 which has been conventionally used to increase the adhesive strength
-Bis (2,4-dihydroxyphenylmethyl) -4-
It may be used in combination with a compound such as a chlorophenol composition.

The adhesive composition used to treat the polyester fibers of the present invention typically comprises the copolymer rubber latex of the present invention.
10 to 180 parts by weight (dry weight) of resorcinol-formaldehyde resin is mixed with 100 parts by weight of the solid content of (b) or (c).

Further, a part of the rubber-like copolymer latex of the present invention in the adhesive composition of the present invention is a styrene-butadiene copolymer rubber latex and its modified latex, acrylonitrile-butadiene copolymer rubber latex and its modified latex, natural rubber latex and the like. One or two or more of them can be substituted.

There is no particular limitation on the method for treating the polyester fiber with this adhesive composition, and it can be treated in the same manner as a known resorcinol-formaldehyde-polymer latex adhesive.

In the present invention, the polyester fiber is first treated with an adhesive composition containing a copolymer rubber latex (b), and then treated with an adhesive composition containing a copolymer rubber latex (c) is used. To be

Copolymer latex attached to polyester fiber (b)
The amount of the adhesive composition containing is usually 1 to the fiber.
6% by weight, preferably 1.5 to 5.5% by weight. 1
When it is less than 6% by weight, the heat-resistant adhesiveness is poor, and when it exceeds 6% by weight, the fiber becomes hard. Also, the copolymer latex (C)
In the case of an adhesive composition containing, it is usually 1% by weight or more, preferably 1.5% by weight or more. When it is less than 1% by weight, the initial adhesive strength is poor, and the effect is not improved even if a large amount is used, which is economically disadvantageous.

The polyester fiber to which the method of the present invention is applied is not particularly limited as long as it is a linear polymer polyester.
The polytestel fiber etc. which are disclosed by 7-50184 gazette etc. are mentioned.

The fibers are usually in the form of threads, cords, continuous filaments, cloths, etc., but may be in other forms.

(Effect of the Invention) The polyester fiber-rubber adhesion method of the present invention gives an initial adhesive force equivalent to that when a conventional adhesive is used, and is extremely remarkably heat resistant as compared with the case where a conventional adhesive is used. Since the strength and the heat resistance and strength of the fiber can be improved, it can be used for manufacturing tires, belts, hoses and the like using polyester fiber.

Hereinafter, the present invention will be described more specifically with reference to examples. The parts and% in the examples and comparative examples are based on dry weight unless otherwise specified.

Reference Example 1 150 parts of water, 0.1 part of tetrasodium salt of ethylenediaminetetraacetic acid, 5 parts of sodium lauryl sulfate, 0.5 part of sodium bicarbonate, 0.5 part of t-dodecyl mercaptan, 0.5 part of potassium persulfate were added to an autoclave equipped with a stirrer. Monomer I shown in Table 1 together with 3 parts was added in an amount 5 times the weight (100
Part) Charged and reacted at 60 ° C. for 15 hours while rotating and mixing. The conversion rate reached 60% or more in all cases. This is the seed latex. Then, into an autoclave equipped with a stirrer, 20 parts of the seed latex and the monomer II shown in Table 1 were charged, and further 4 parts of ethylenediaminetetraacetic acid were added.
0.1 part of sodium salt, 2 parts of sodium lauryl sulfate, t-
Dodecyl mercaptan 0.5 part, potassium persulfate 0.3
Parts and water were charged so that the total amount would be 150 parts, and the reaction was carried out at 60 ° C. with rotary mixing. When the polymerization conversion rate reached 95%, 0.05 part of hydroquinone was added to stop the reaction, and the unreacted monomer was removed by reducing the pressure to obtain copolymerized latex A and B.

Example 1 16.6 parts of resorcinol, formalin aqueous solution (37%
(Concentration) 14.6 parts, sodium hydroxide 1.3 parts water 33
It was dissolved in 3.5 parts and reacted with stirring at 25 ° C. for 2 hours. This is referred to as liquid (a).

Next, into the liquid (a), latex A or latex B 10
0 part was added, and the mixture was reacted at 25 ° C. for 20 hours with stirring.
Next, Vulcabond E (ICI Vulnax product Vulcabond
35 parts of E) were added. This aqueous solution has a solid content of 20
Adjusted to%. These are designated as (I) -A solution and (I) -B solution, respectively.

Polyester tire cords (1500D /
2) was soaked.

After the immersion treatment, heat treatment was performed at 240 ° C. for 1 minute. This treated polyester tire cord was sandwiched between natural rubber compounds produced according to the compounding recipe shown in Table 2 at 170 ° C.
Press vulcanized for 0 minutes. After vulcanization, the cord was taken out from the rubber and the strength was measured. The strength of the cord before vulcanization was 22.5 kg (average of 10 cords), but after vulcanization (I)
The solution treatment using the -A solution showed a 31% decrease in the strength, whereas the treatment with the (I) -B solution showed a 15% decrease in the strength.

Next, the polyester tire cord treated with the above-mentioned (I) -B solution was subjected to the immersion treatment again using the (I) -A solution. After the treatment, heat treatment was performed at 240 ° C. for 1 minute. The treated polyester tire cord was sandwiched between natural rubber compounds prepared according to the compounding recipe shown in Table 2 and press-vulcanized. The adhesive strength between the tire cord and the rubber was evaluated by the T adhesive strength test method (measurement temperature 20 ° C., relative humidity 65%, pull-out test of 24 wires). The results are shown in Table 3 in comparison with the case where only one treatment with the (I) -A solution or the (I) -B solution was performed. The amounts of the (I) -A liquid and the (I) -B liquid attached are 2% by weight and 5% by weight, respectively, in terms of solid content with respect to the polyester fiber.

Table 2 Rubber compounding formula Natural rubber 100 parts Lead phosphite 5 Stearic acid 2 Sulfur yellow 2.5 FEF Carbon black 45 Process oil 5 N-Oxydiethylene-2-benzothiazyl sulfenamide 1 2,2,4-Trimethyl-1,2 -Dihydroquinoline polymer 0.2 Example 2 Fourth monomer as the monomer used in the first and second stage polymerization
Copolymer latices C to H produced under the same conditions as in Reference Example 1 except that the ones shown in the table were used and mixed with the liquid (a) and VALCABOND E in the same manner as in Example 1 (I) -C to (I)-
Liquid H was prepared, and the polyester tire cord was subjected to immersion treatment using this liquid. After the heat treatment, a dipping treatment was carried out with the liquid (I) -A of Example 1 to carry out the heat treatment. Using this treated tire cord, vulcanization adhesion with natural rubber was performed in the same manner as in Example 1. The cord strength and adhesive strength were measured and the results shown in Table 5 were obtained.

Example 3 (I) -I- (I)-was prepared in the same formulation as in Example 1 by using the latexes I-Y produced in the same manner as in Reference Example 1 except that the monomers shown in Table 6 were used. A polyester tire cord was subjected to a dipping treatment using a liquid Y, and then (I) -A of Example 1
After the immersion treatment using the liquid, a vulcanization adhesion test was performed under the same conditions as in Example 1. The results are shown in Table 7.

Example 4 Using the solution (a) used in Example 1 and the latex B and VALCABOND E, solutions having the ratios and concentrations shown in Table 8 were prepared.

After dipping the polyester tire cord in these treatment liquids, the polyester tire cord was subsequently immersed in the liquid (I) -A of Example 1 to test the adhesive strength. The test method was the same as in Example 1. The results are shown in Table 9.

Example 5 Resorcinol 11 parts, formalin aqueous solution (37% concentration) 16.2 parts, sodium hydroxide 0.3 parts in water 23
It was dissolved in 8.5 parts and reacted with stirring at 25 ° C. for 6 hours. Next, 100 parts of the latex A of Example 1 was added thereto, and the mixture was reacted at 25 ° C. for 20 hours while stirring. This aqueous solution was adjusted to a solid content concentration of 20%. This is designated as (II) -A solution.

First, a polyester tire cord was used in a test single cord dipping machine to prepare liquid (I) -A or (I) -of Example 1.
Immersion treatment in liquid B and heat treatment at 240 ° C. for 1 minute, followed by immersion treatment in liquid (II) -A and heat treatment at 240 ° C. for 1 minute. The treated polyester tire cord was sandwiched with a natural rubber compound produced by the compounding recipe shown in Table 2 and press-vulcanized. The results of the adhesive strength test are shown in Table 9.

Claims (1)

[Claims] 1. When vulcanizing and adhering polyester fiber and rubber, first, (1) resorcinol-formaldehyde resin (a), 35 to 75% by weight of conjugated diene monomer, ethylenically unsaturated acid monomer A composition comprising 0.5 to 25% by weight of vinyl pyridine, 15 to 45% by weight of vinylpyridine, and 0 to 40% by weight of another monomer copolymerizable with the above monomers, and a rubber latex (B). And then (2) resorcinol-formaldehyde resin (a), 45 to 95% by weight of a conjugated diene monomer, 5 to 35% by weight of vinylpyridine, and an ethylene-based copolymerizable with these monomers. A polyester fiber and a rubber, characterized in that a polyester fiber treated with a composition comprising a copolymer rubber latex (c) consisting of 0 to 30% by weight of other monomers excluding saturated acid monomer is used. Adhesion Law.