JPH02164746A - Glass fiber for reinforcing rubber - Google Patents

Abstract

PURPOSE:To improve the adhesive property of glass fiber to various rubbers by treating the glass fiber with a soln. contg. a resorcin-formaldehyde precondensate, vinylpyridine-styrene-butadiene latex and chlorosulfonated polyethylene as essential components. CONSTITUTION:This glass fiber for reinforcing rubber is glass fiber surface- treated with a soln. contg. a resorcin-formaldehyde precondensate, vinylpyridine- styrene-butadiene latex and chlorosulfonated polyethylene as essential components. The treated glass fiber may further be treated with a secondary soln. contg. nitrile rubber or hydrogenated nitrile rubber, isocyanate and chlorinated rubber. This glass fiber has superior adhesive strength to various rubbers and especially high adhesive property to heat resistant rubber such as hydrogenated nitrile rubber or chlorosulfonated polyethylene.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to rubber reinforcing glass fibers used for reinforcing various rubber products, more specifically, to a unique method for better adhesion between glass fibers and rubber. This relates to surface-treated glass fibers.

[Prior Art] Rubber products such as rubber belts and tires are widely reinforced with glass fibers in order to improve their strength, toughness, dimensional stability, etc. However, in these applications, they are subjected to repeated bending stress, resulting in bending fatigue, resulting in decreased performance, and peeling between the glass fiber and the rubber matrix is likely to occur.

In order to prevent this peeling and the deterioration of performance, it is necessary to increase the compatibility and adhesive strength between the glass fiber and the rubber matrix, and various treatment agents have been proposed to be applied to the surface of the glass fiber. The most common method is to use a dispersion of resorcinol/formaldehyde resin and various latexes. However, even with glass fiber-reinforced rubber bodies that have undergone this treatment, the adhesive strength is not necessarily sufficient, and products with high adhesive strength have the problem that it is difficult to obtain satisfactory water resistance. be. In addition, in recent years, rubber materials with higher physical properties have been used in various applications, and in this case, depending on the rubber material, adhesive strength may not be fully demonstrated only by treatment with these chemicals. Various methods have been proposed in which, after treatment with a chemical, treatment is performed with a different chemical. However, even in this case, the adhesive strength is not necessarily sufficient, and this tendency is particularly strong when hydrogenated nitrile rubber or the like is used as the rubber matrix.

[Means for Solving the Problems] In view of the problems of the prior art, the present inventors have arrived at the present invention as a result of intensive studies. That is, the first aspect of the present invention is a resorcinol-formaldehyde initial condensate, vinylpyridine-styrene-butadiene (hereinafter abbreviated as VP) and chlorosulfonated polyethylene (hereinafter referred to as CS).
This glass fiber for rubber reinforcement is characterized by being treated with a liquid containing M) as its main component.

The Vp used in the present invention has a vinylpyridine:styrene:butadiene ratio of 10 to 2010 to 2026 by weight.
A value of 0 to 80 is suitable, and Viratex (product name,
(manufactured by Sumitomo Nogatta Co., Ltd.), 0650 (trade name, manufactured by Japan Synthetic Rubber Co., Ltd.), Nirapol 1218FS (trade name, manufactured by Nippon Zeon Co., Ltd.), etc. can be suitably used.

Moreover, there are no particular restrictions on the C3M, and various types of C3M commercially available for boat fishing can be used as appropriate.

The resorcinol/formaldehyde initial condensate is a water-soluble initial addition condensation product of resorcinol and formaldehyde enriched in oxymethyl groups obtained by reacting resorcinol and formaldehyde in the presence of an alkaline catalyst such as alkali hydroxide, ammonia, or amine. can be used suitably.

The weight of pure resorcinol/formaldehyde is preferably 15% by weight or less based on the solid weight of Vp and C3M, and the ratio of resorcinol and formaldehyde is t:O,S~2.5. In the present invention, the ratio of Vp to CSM is preferably 9:1 by weight.
The range of VpO to 525 is preferable; if the amount of VpO is less than this, the adhesion will not be sufficient, and if it is more than this, the fatigue resistance will be poor.

In the present invention, it is also effective to add a small amount of nitrile rubber (hereinafter referred to as NBR) to further improve adhesiveness.

The amount of solid content deposited by this treatment is 1% per glass fiber.
It is preferably in the range of 5 to 25% by weight; if it is less than this range, the fatigue performance will not be sufficient, and if it exceeds this range, the adhesiveness will become unstable, which is not preferred.

After this treatment, the glass fibers are usually dried at a temperature in the range of 200 to 350°C. When applying the glass fibers as they are to various rubber materials, the glass fiber bundles are first twisted as is generally done. Afterwards, multiple cords are tied together and further twisted to form a glass cord. The glass fibers treated in this way can be applied as they are to various rubber materials and exhibit good physical properties as glass fiber-reinforced rubber bodies.

The glass cord according to the present invention also has excellent heat resistance, and in order to fully demonstrate its characteristics, it is necessary to use a heat-resistant rubber material as the target rubber material, specifically hydrogenated nitrile rubber (hereinafter referred to as H-
It is preferable to select NBR) or C3M; in this case, since the glass cord has poor adhesion as it is, it is preferable to further treat it with a second chemical solution, and the second invention was made from this point of view. be. That is, resorcinol formaldehyde initial condensate and Vp and C
This glass fiber for rubber reinforcement is treated with a first liquid containing 3M as a main component and then treated with a second liquid containing NBR or H-NBR, isocyanate, and chlorinated rubber.

Isocyanates used in the present invention include methylene diphenyl diisocyanate, toluene diisocyanate, triphenylmethane triisocyanate, naphthalene diisocyanate, etc. Among these, methylene diphenyl diisocyanate, which has appropriate film hardness and good adhesiveness, is most preferred.

As NBR, commonly available commercially available NBRs having a nitrile bond content in the range of 20 to 40% can be used. Also, H-NBR can be used instead of NBR,
By using this H-NBR, it has excellent adhesion and extremely good heat resistance, and is particularly suitable for applications requiring high heat resistance. The H-NBR preferably has an unsaturation degree in the range of 14 to 28. If the unsaturation degree is lower than this, the heat resistance will be further improved, but the adhesiveness will be poor, which is not preferable.

The chlorinated rubber preferably has a chlorination degree of 40 to 80.

The ratio of isocyanate to NBR or H-NBR is preferably in the range of 0.5 to 3 to 1 isocyanate.
If it is less than this range, the film will become too hard, and if it exceeds this range, the adhesion and adhesion will become unstable, which is undesirable.
Alternatively, the amount of H-NBR is preferably in the range of 5 to 15% by weight on a solid basis, and if it is less than this range, sufficient adhesive strength cannot be obtained.

In addition, if it exceeds this range, the adhesion becomes unstable, which is not preferable.Also, it goes without saying that NBR and H-NBR can be used in combination, and there is no restriction on the quantitative range. In addition, the second liquid uses chlorinated rubber, which has excellent film-forming ability.
A rubber reinforcing material with higher adhesive strength can be obtained.

The amount of chlorinated rubber is 10% for NBR or H-NBR.
The range of 100% by weight is preferred, and various commonly used vulcanizing agents such as zinc white, magnesium oxide, sulfur and litharge can also be used.

After treatment with the second liquid, drying is performed, but the drying conditions are not particularly limited.
The glass fiber used in the present invention is not particularly limited, but it is usually a glass fiber with a thickness of 5 to 13 μm that is coated with an anchoring agent, an adhesive, a surfactant, etc. Apply a sizing agent consisting of 20
About 0 glass fibers are used.

The glass fibers treated according to the present invention are applied to various rubbers, and the types of target rubbers are not particularly limited, but when applied to rubbers with excellent heat resistance such as H-NBR and C3M rubbers, The glass fiber of the present invention significantly exhibits its characteristics.

Hereinafter, the present invention will be explained in detail with reference to Examples.

Example: VP containing vinylpyridine, styrene and butadiene in a ratio of 15:15 to 320 parts by weight of an addition condensate of lusorcin and formaldehyde (manufactured by Jubilee Nogatta Co., Ltd., trade name: Viratex, solid content: 41% by weight) )5
11 parts by weight, 131 parts by weight of chlorosulfonated polyethylene (C5M450 manufactured by Steel Chemical Co., Ltd., solid content 40% by weight),
22 parts by weight of aqueous ammonia (25%) was added with stirring, and water was added to make a total of 1000 parts by weight to prepare a first liquid.

Three glass fiber bundles, each consisting of 200 glass fibers of 9 μm, were aligned and treated with the first solution according to a conventional method. The solid content adhesion rate at this time was 19% by weight. 280
After drying at °C for 22 seconds, this glass fiber bundle was first twisted 16 times per 10 cm, then 13 fiber bundles were pulled together and final twisted 8 times per 10 cm to form a reinforcing glass cord. Various physical properties were evaluated using this glass cord. The results are shown in Table 1.

"L Engineering J Echloroprene Rubber (manufactured by Showa Denki Dupont Co., Ltd., Mura) 0 Len GRT60. Neo-Olen-RT40) 10
Carbon black HAF 45 based on 0 parts by weight
parts by weight, 5 parts by weight of zinc white, 5 parts by weight of antioxidant, 5 parts by weight of process oil, 4 parts by weight of magnesium oxide, 1 part by weight of stearic acid, 0.5 parts by weight of sulfur, 0.5 parts by weight of paraffin wax, Contains 1 part by weight of NA-22.

In addition, each measurement method is as follows.

LUL supporting speed; 300mm/min, clamp interval i 25(lt
l, Clamp: Measuring the tensile strength of the glass cord using the winding method.

The random 11-branch test piece was made by placing 19 to 20 treated reinforced glass cords/25 cm on a rubber sheet (3 mm thick), covering it with a cloth, and applying a pressure of 20 Kg/cd at 150°C for 30 minutes. It was prepared by vulcanization molding. Peel this thing at a rate of 50
Measured at 1 m 1 minute.

Discharge L1 The test piece is 5 kg of treated glass cord at 1 mm intervals.
Apply a tension of It was made into one belt.

A belt was applied to two pulleys of 100mmφ and 25111φ, with part of the 25mmφ pulley immersed in water, and after rotating at 1000r and 9m for 24 hours, the test piece was taken out and its tensile strength was measured. was measured.

LL! The IJL well-treated glass cord was attached to a lamination testing machine from both sides with adhesive tape and paper adhesive tape (7210.11aJi), a load of 3 kg was applied, and the cord was bent at 120 times/min (1202 angle) until cutting. I read the number of times. (Normal temperature) On the other hand, the glass fibers left at 120°C for 7 days were similarly measured. (Heat resistance) Examples 2 to 5 Glass cords were obtained in the same manner as in Example 1, except that the composition of the first liquid was as shown in Table 1, and the total amount was 1000 parts by weight, and various physical properties were determined in the same manner. was evaluated. The results are shown in Table 1. The nitrile rubber added in Example 5 was Nilapol 1562 manufactured by Nippon Zeon Co., Ltd., solid content 4.
It is 1% by weight.

Comparative Example 1.2 As shown in Table 1, C3M-free (Comparative Example 1) 1st
Liquid, Contains No Vp (Comparative Example 2) Glass cords were fabricated and evaluated in the same manner as in Examples 1 to 5, except that the first liquid was used. The results are shown in Table 1.

Comparative Examples 3 to 5 Carboxylated SBR (
Asahi Kasei Kogyo Co., Ltd., L-5702, solid content 48% by weight) (
Comparative Example 3), butadiene rubber (manufactured by Japan Synthetic Rubber Co., Ltd., 07
00, solid content 57% by weight) (Comparative Example 4), carboxylated NBR (manufactured by Nippon Zeon Co., Ltd., Nilapol 1571, solid content 40% by weight) (Comparative Example 5) except that the composition was as shown in Table 1. Create the glass cord in the same way as Examples 1 to 5! J
and evaluated it. The results are shown in Table 1.

Table 1 (blank below) Example 6 Using the glass cord treated in Example 1, 36 parts by weight of polyisocyanate (manufactured by Mitsui Toatsu Co., Ltd., MDI-PH, metaphenylene diisocyanate type), H-NBR compound (Zeon Co., Ltd., 2020) 60 parts by weight, 12 parts by weight of chlorinated rubber (manufactured by Jiryuka Co., Ltd., CR-15), 1 part by weight of Zinc White No. 3 as a vulcanization agent, and 891 parts by weight of a solvent consisting of methyl ethyl ketone and toluene. It was treated with two liquids and dried at 155° C. for 48 seconds. The solid content adhesion rate by this second liquid treatment was 2.3% by weight. Various physical properties were evaluated using this reinforcing glass cord. The results are shown in Table 2 along with the treatment liquid composition and the rubber used.

For 100 parts by weight of 2S J Engineering H-NBR (Nippon Zeon Co., Ltd., 2020), 50 parts by weight of carbon black HA F, 5 parts by weight of zinc white, 3 parts by weight of plasticizer, 2 parts by weight of anti-aging agent. , containing 3 parts by weight of a vulcanization accelerator.

■CSM (manufactured by Showa Denko/Dupont, C5M40)
50 parts by weight of carbon black 5RF, 5 parts by weight of magnesium oxide, 3 parts by weight of pentaerythritol, 4 parts by weight of a plasticizer, 3 parts by weight of an anti-aging agent, and 2 parts by weight of a vulcanization accelerator were blended with 100 parts by weight.

Examples 7 to 15 The glass cords of Examples 1 to 5 were treated in the same manner as in Example 6, except that the composition of the second liquid was as shown in Table 2, to obtain reinforcing glass fiber cords. Physical properties were evaluated.

In addition, the same treatment was performed using an NBR compound (manufactured by Nippon Zeon Co., Ltd., 1042) instead of the H-NBR compound as the second liquid, and the physical properties were evaluated. The results are shown in Table 2.

Comparative Examples 6 to 10 The glass cords obtained in Comparative Examples 1 to 5 were treated with the second liquid in the same manner as in Example 6.

The physical properties of this product were evaluated and the results are shown in Table 2.

[Effect of the invention] The glass fiber of the present invention has excellent adhesion to various rubbers,
In particular, it has excellent adhesion to heat-resistant rubbers such as H-NBR, C3M, etc., and can be used in a wide range of applications.

Claims (2)

[Claims] (1) A glass fiber for rubber reinforcement, characterized in that it has been treated with a liquid whose main components are a resorcinol-formaldehyde initial condensate, vinylpyridine-styrene-butadiene, and chlorosulfonated polyethylene. (2) After treatment with a first liquid containing a resorcinol-formaldehyde initial condensate, vinylpyridine-styrene-butadiene, and chlorosulfonated polyethylene as main components, a first liquid containing nitrile rubber or hydrogenated nitrile rubber, isocyanate, and chlorinated rubber is treated. Glass fiber for rubber reinforcement characterized by being treated with two liquids.