JPH0356579A - Adhesive composition for rubber to fiber - Google Patents

Abstract

PURPOSE:To obtain the subject composition, containing a resorcin-formalin resin and a specific copolymer latex and suitable for bonding fiber contained in a rubber product, such as tire, to rubber with hardly any deterioration in tenacity of fiber cords after heat treatment. CONSTITUTION:The objective composition containing (A) a resorcin-formalin resin and (B) a copolymer latex, composed of 35-75 wt.% conjugated diene-based monomer (preferably 1,3-butadiene), 5-35 wt.% vinyl pyridine-based monomer (preferably 2-vinylpyridine) and 2-60 wt.% monomers (preferably styrene, etc.) copolymerizable therewith and having 50-350 nm, preferably 110-250 nm weight- average particle diameter and 105-180, preferably 110-160 Mooney viscosity.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an adhesive composition of rubber and fiber. More specifically, the present invention relates to an improved adhesive composition suitable for bonding rubber to fibers contained in rubber products such as tires and belt hoses.

BACKGROUND OF THE INVENTION Fibers such as nylon, polyester, and aramid have been widely used as fibers for reinforcing rubber in rubber products such as tires, belts, and hoses. However, both fibers
Adhesive compositions (hereinafter referred to as RF resins), which have poor adhesion to rubber by themselves, are composed of butadiene-styrene-vinylpyridine copolymer latex alone or a mixture of it and other rubber latexes, and resorcinol-formalin resin (hereinafter referred to as RF resin). It is common that adhesive processing is performed using RFL (hereinafter referred to as RFL) for practical use.

For any type of fiber, if you want to obtain good adhesion with rubber without causing any problems in practice, immerse the fiber in RFL.
After drying, it is necessary to heat-treat at a high temperature of 170°C or higher for nylon LM fibers, or 220°C or higher for polyester fibers and aramid fibers, but in this process, the strength of the fibers themselves before treatment decreases. There is a problem.

For any type of fiber, heat treatment at a higher temperature to obtain higher adhesion with rubber will reduce the strength of the lm fibers, and conversely, in order to minimize the decrease in strength of the fibers, heat treatment at a relatively low temperature will reduce the strength of the lm fibers. When heat-treated, the adhesive strength with rubber, especially the peel adhesion strength and the rate of rubber adhesion to the fibers after peeling, decreases, so the strength of the fibers after heat treatment is less likely to decrease, and the adhesive composition can provide high adhesive strength. development was strongly desired.

Means for Solving the Problems> The inventors of the present invention have made extensive studies to solve the above problems, and as a result, have completed the present invention.

That is, the present invention comprises (A) resorcinol-formalin resin (B) 35 to 75% by weight of a conjugated diene monomer, 5 to 35% by weight of a vinylpyridine monomer, and a monomer copolymerizable with these. Consisting of 2-60% by weight, weight average particle size 50-850
The present invention provides a rubber-fiber adhesive composition comprising a copolymer latex having a Mooney viscosity of 105 to 180 nm%.

The present invention will be explained in detail below.

Examples of the conjugated diene monomers used in the copolymer latex of the present invention include 1,3-butadiene, 2-methyl-1,8-butadiene, and 2,3-dimethyl-1,8-
Examples include butadiene, and one or more of these can be used. Among these, 1,3-butadiene is preferred.

If the conjugated diene monomer content is less than 35% by weight, the adhesive strength during vulcanization (hereinafter referred to as initial adhesive strength) will decrease, and if it exceeds 75% by weight, high temperature and long-term vulcanization will occur, especially in polyester fibers. The adhesive strength (hereinafter referred to as heat-resistant adhesive strength) decreases. Preferably 6 for nylon fibers.
0 to 70% by weight, 40 to 65% by weight for polyester and aramid fibers.

Examples of the vinylpyridine monomer used in the copolymer latex of the present invention include 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, etc. One type or two or more types can be used. Among these, 2-vinylpyridine is preferred. If the vinylpyridine content is less than 5% by weight, both initial and heat-resistant adhesive strength will decrease, and if it exceeds 35% by weight, the initial adhesive strength will decrease. Desirably 10-25% by weight
It is.

Other copolymerizable monomers that can be used in the copolymer latex of the present invention include aromatic vinyl monomers such as styrene, α-methylstyrene, and monochlorostyrene, acrylonitrile, methacrylonitrile, etc. Vinyl cyanide monomers, ethylenically unsaturated carboxylic acid monomers such as acrylic acid, methacrylic acid, itaconic acid, fumaric acid, and methyl (meth)acrylate, ethyl (meth)acrylate, 2-ethylhexyl acrylate Examples include ethylenically unsaturated carboxylic acid alkyl ester monomers such as ethylenically unsaturated carboxylic acid alkyl ester monomers, and one type or two or more types of each can be used.

Among these, aromatic vinyl monomers alone or combinations thereof with one or more monomers selected from other monomers are preferable, and styrene alone or styrene and 4-methylstyrene, acrylonitrile, Particularly preferred are combinations with monomers selected from acrylic acid, itaconic acid, and methyl methacrylate.

If the physical strength of these copolymerizable monomers is less than 2% by weight or more than 60% by weight, the initial adhesive strength will decrease.

Preferably 2 to 35% by weight for nylon fibers.
, 5-5 for polyester and aramid fibers
It is 5% by weight.

The Mooney viscosity of the copolymer latex of the present invention is 105~
It is 180.

If the Mooney viscosity is less than 105, the strength of the fiber cord after heat treatment will decrease significantly, and if it exceeds 180, the initial adhesive strength will decrease. Desirably it is 110-160.

The weight average particle diameter of the copolymer latex of the present invention is 50 to
It is 350 nm. When the weight average particle diameter is less than 59 nm, the heat-resistant adhesive strength particularly in polyester fibers decreases,
Moreover, if it exceeds 350 nm, stable polymerization of the copolymer latex becomes difficult.

Desirably 711-280 nm. More preferably 1
10 11 to 250 nm.

The copolymer latex of the present invention can be produced by a known emulsion polymerization method,
For example, it is produced by a general polymerization method, a two-stage polymerization method, a power feed polymerization method, etc. Further, there is no particular restriction on the method of adding the monomer, and any method such as a batch addition method, a divided addition method, a continuous addition method, etc. can be adopted.

In addition, a part of the copolymer latex of the present invention may be used as styrene-butadiene copolymer latex, carboxy-modified styrene-butadiene copolymer latex, acrylonitrile-butadiene copolymer latex, or carboxy-modified acrylonitrile-butadiene copolymer latex. It is desirable that the amount is less than 50 parts by weight in 100 parts by weight of the butadiene copolymer latex.

As the resorcinol-formalin resin in the present invention, conventionally known ones can be used.

Further, the amount of the resorcinol-formalin resin (solid content) used is preferably 5 to 50 M parts per 100 parts by weight of the copolymer latex (solid content). More preferably, it is 8 to aoiit parts.

The adhesive composition of the present invention contains 2,6-bis(2,4-dihydroxyphenylmethyl)-4-chlorophenol i
Ganrin*bianig, blocked isocyanate, ethylene urea, polyepoxide, modified polyvinyl chloride, and the like can be appropriately blended.

〔Example〕

The present invention will be specifically explained below with reference to Examples.
The present invention is not limited in any way by these Examples. Note that all parts and % in the examples mean parts by weight and % by weight unless otherwise specified.

Production of copolymer latex A, C, K, M> In an autoclave with a stirrer, 130 parts of water, 3.5 parts of potassium rosinate, sodium naphthalene sulfonate, 1 part of formalin condensate, 0.5 parts of sodium hydroxide. Add and dissolve. To this, 100% of the monomer mixture shown in Table 1 is added.
tert-dodecylmercabutane shown in Table 1 was further added and emulsified. Next, 0.5 part of potassium persulfate is added, and the entire mixture is maintained at 50° C. for polymerization. When the polymerization conversion rate reaches 92%, hydroquinone 0,
Add 1 part to stop the polymerization. The resulting copolymer latex was distilled under reduced pressure to remove unreacted monomers, and its viscosity is shown in Table 1.

Production of copolymer latex B, G, H, L> In an autoclave equipped with a stirrer, add 110 parts of water, 2.5 parts of potassium rosinate, 1 part of sodium naphthalene sulfonate/formalin condensate, and 0.0 parts of sodium hydroxide. Add 5 parts and dissolve. To this, the monomer mixture 10 shown in Table 1 was added.
0 part was added, and further tert-dodecylmercabutane shown in Table 1 was added and emulsified. Then potassium persulfate 0. 5 parts were added and the whole was maintained at 50°C to carry out polymerization. When the polymerization conversion rate reaches 92%, 0.1 part of hydroquinone is added to stop the polymerization. The obtained copolymer latex was subjected to vacuum distillation to remove unreacted monomers, and copolymer latexes B, G, H, and L were obtained.

Table 1 shows the weight average particle diameter and Mooney viscosity of these copolymer latexes.

Production of copolymer latex I> In an autoclave equipped with a stirrer, 170 parts of water, 6 parts of potassium rosinate, sodium naphthalene sulfonate, 1 part of formalin condensate, and 0.0 parts of sodium hydroxide. Add 5 parts and dissolve. To this, 100% of the monomer mixture shown in Table 1 was added.
and 0.0 parts of tert-dodecylmercabutane.
Add 25 parts and emulsify. Then potassium persulfate 0
．． 5 parts were added and the whole was maintained at 50°C to carry out polymerization. When the polymerization conversion rate reaches 92%, 0.1 part of hydroquinone is added to stop the polymerization. The obtained copolymer latex was distilled under reduced pressure to remove unreacted monomers to obtain a copolymer latex.

Table 1 shows the weight average particle diameter and Mooney viscosity of this copolymer latex.

Production of copolymer latex D, H> In an autoclave equipped with a stirrer, 140 parts of water, 3 parts of polyoxyethylene lauryl egotel, 0.05 part of sodium ethylenediaminetetraacetate, and the tert-dodes shown in Table 1 were added. Silmerkabutan and potassium persulfate 0.3 parts,
In addition, 100 parts of the monomer mixture shown in Table 1 were charged, and the entire mixture was maintained at 46°C to carry out polymerization. Polymerization conversion rate is 95%
When it reaches, add 0.05 part of hydroquinone,
Stop polymerization. Next, unreacted monomers were removed by vacuum distillation to obtain copolymer latexes D and E.

Table 1 shows the weight average particle diameter and Mooney viscosity of these copolymer latexes.

Production of copolymer latex F, J> In an autoclave equipped with a stirrer, add 150 parts of water, 7 parts of polyoxyethylene lauryl ether, 0.05 parts of sodium ethylenediaminetetraacetate, and the tert shown in Table 1.
0.8 parts of dodecyl mercabutane and potassium persulfate,
In addition, 100 parts of the monomer mixture shown in Table 1 were charged, and the entire mixture was maintained at 50°C to carry out polymerization. Polymerization conversion rate is 95%
When it reaches, add 0.05 part of hydroquinone,
Stop polymerization. Next, unreacted monomers were removed by vacuum distillation to obtain copolymer latexes F and J.

The weight average particle diameter and Mooney viscosity of these copolymer latexes are shown in Table 1.

Production of copolymer latex N> In an autoclave equipped with a stirrer, 100 parts of water, 1.5 parts of polyoxyethylene lauryl ether, 0.05 parts of sodium ethylenediaminetetraacetate, and 0.0 parts of tert-dodecylmercabutane were added. 2 parts and 0.3 parts of potassium persulfate, and 100 parts of the monomer mixture shown in Table 1,
Polymerization is carried out by keeping the whole at 50°C. When the polymerization conversion rate reaches 50%, tert-dodecylmercabutane 0.15
Add parts. Further, when the polymerization and conversion rate reaches 95%, 0.05 part of hydroquinone is added to stop the polymerization.

Next, unreacted monomers were removed by vacuum distillation, but a large amount of aggregate was generated, so this was removed using a 300 meSh wire gauze to obtain copolymer latex N.

This copolymer latte weight average particle diameter of Table 1 of Moony's degree Shown in 1.

O Example-1 (RFL, [Preparation of
Aging is performed at 5° C. for 6 hours to create an RF resin.

Next, 80% of each of the copolymer latex shown in Table 3 was added.
(solid content) and 20 parts (solid content) of styrene-ptadiene copolymer latex (manufactured by Sumitomo Naugatac Co., Ltd.; J9049), and the solid content was reduced to 20% with water. The mixture was aged at 25° C. for 18 hours to obtain RFL liquids 1 to 9.

Tire Cord Dipping Treatment, Cord Strength and Adhesive Strength Measurement Using a test single cord dipping machine, nylon tire cords (1890D/2) were dipped in each of the obtained RFL liquids 1 to 9. The strength of each of the treated tire cords was measured in accordance with JIS-L1017. The results are shown in Table-3.

In addition, each of the treated tire cords was sandwiched between rubber compounds based on the formulation shown in Table 2, and vulcanization-pressed at 140° C. for 45 minutes.

ASTM D2188-67 (H Pull Te
The adhesive strength was measured according to st). The results are shown in Table-3.

0 Example-2 (Preparation of RFL liquid) 1.3 parts of sodium hydroxide, 16.6 parts of resorcinol, and 14.6 parts of 87% formalin were added to 88.5 parts of water, and aged at 25°C for 2 hours. By doing so, RF resin is created.

Next, 85% of each of the copolymer latex shown in Table 4 was added.
(solid content) and carboxy-modified styrene-butadiene copolymer latex (manufactured by Sumitomo Naugatuck; SN-7
55) Add 23.3 parts of the obtained RF resin to 15 parts (solid content) and age at 25°C for 20 hours. Thereafter, 2,6-bis(2,4-dihydroxyphenylmethyl)-4-k007x/-l(I C I
Add 35 parts of Vulkabond E) manufactured by Vulnax, adjust the solid content to 15% with water, and make the R shown in Table 4.
FL solution lO~22 was obtained.

Tire Cord Dipping Treatment, Cord Strength and Adhesive Strength Measurement Using a test single cord dipping machine, polyester tire cords (1500D/2) were dipped in each of the obtained RFL liquids 10 to 22. The strength of each tire cord subjected to the immersion treatment was measured in accordance with JIS-L1017.

The results are shown in Table 4.

Further, this treated tire cord was sandwiched between rubber compounds based on the compounding recipe shown in Table 2, and vulcanization-pressed at 140°C for 45 minutes and at 170°C for 90 minutes.

ASTM D2 1 3 8-67 (H Pull
Adhesive strength was measured according to Test), and the decrease in adhesive strength due to high-temperature coating was measured.

In addition, as shown in Fig. 1, four treated cords 2 were embedded at equal intervals on the surface layer of the rubber compound 1 shown in Table 2, and heated at 170°C.
Vulcanization pressing was performed for 100 minutes to prepare a test piece for measuring heat-resistant peel adhesion.

Using this test piece, the tips of four cords were fixed with adhesive tape 3 as shown in FIG. 2, and the cord was peeled from rubber compound 1 in the direction of the arrow to measure the heat-resistant peel adhesive strength. In addition, the state of rubber adhesion to the cord after peeling was visually determined. 5
(Excellent) -1 (Poor) The results are shown in Table 4.

Example 8 (Preparation of RFL liquid) Add 10.49 parts of 25% ammonia water to 882 parts of pure water, stir and mix, then add 87 parts of 75% resorcinol-formalin resin (manufactured by Sumitomo Chemical Co., Ltd.; Sumikanol 700). Stir and mix. Next, add copolymer latex 1 shown in Table 5.
00 parts (solid content) and stirred for 3 minutes, then added 1 part of pure water
A mixture of 42 parts and 18.6 parts of 87% formalin water was added, stirred for 3 minutes, and then aged at room temperature for 12 hours.
RFL liquids 23 to 32 shown in Table 5 were obtained.

Cord immersion treatment, cord strength and adhesion measurement〉Applicable R
Twaron 1001 (manufactured by Akzo Corporation: aramid fiber cord, adhesive finished product) (16
80DX2) was immersed, dried at 30°C for 60 seconds, and then baked at 235°C for 90 seconds. This treated cord was sandwiched between rubber compounds based on the formulation shown in Table 2, and vulcanization-pressed at 140° C. for 45 minutes.

ASTM D2 1 8 8-6 7 (H Pu
The adhesion force was measured according to 11 Test). Display the results -
5.

Furthermore, the strength of each of the treated cords was measured according to JIS-L1070. The results are shown in Table-5.

Table 2 Compounded rubber prescription Natural rubber SRF carbon REF carbon binder styrenated phenol Zinc stearate Flower vulcanization accelerator Cz* Sulfur 100 parts 20 parts 20 parts 5 parts 2 parts 2.5 parts 5 parts I part 3 parts *: N-cyclohexyl-2-benzothiazyl sulfenamide <Effects of the invention> The adhesive composition of the present invention shows less decrease in the strength of fiber cords after heat treatment than conventional adhesive compositions, and has a strong bond between rubber and fibers. Gives good adhesion between.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a test piece for measuring heat-resistant peel adhesive strength of the present invention, and FIG. 2 is a perspective view showing a test piece used for measuring heat-resistant peel adhesive force. 1...Rubber compound, 2...Processing code, 8...
Adhesive tape special rT. I don't have a friend, I don't have a friend.

Claims (1)

[Scope of Claims] (A) resorcinol-formalin resin; (B) 35 to 75% by weight of a conjugated diene monomer, 5 to 35% by weight of a vinylpyridine monomer, and a monomer copolymerizable with these. Weight average particle size 50, consisting of 2 to 60% by weight
350 nm and a Mooney viscosity of 105 to 180.