JPH11172041A - Resin-vulcanized rubber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin-vulcanized rubber composition which is not corrosive to a metallic part with which it is in contact even where the metallic parts is not coated with a rust preventive and has a high vulcanization rate by adding an alkyl-containing a aromatic sulfonic acid to a composition comprising a natural or synthetic rubber and an alkylphenolic resin. SOLUTION: 100 pts.wt. natural or synthetic rubber is mixed with 1-25 pts.wt. vulcanizing agent being an alkylphenolic resin obtained by condensing a 1-18C alkyl-containing phenol with formaldehyde, and 0.01-50 pts.wt. vulcanization accelerator being a 2-30C alkyl-containing aromatic sulfonic acid to obtain a resin-vulcanized rubber composition. This composition may contain, if necessary, a filler such as carbon black, calcium carbonate, clay, silica, zinc oxide, magnesium oxide, or titanium white or a softener such as a fatty acid, a paraffinic process oil, an aromatic process oil, or a wax.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an improvement in a resin vulcanized rubber composition comprising a natural rubber or a synthetic rubber and an alkylphenol resin.

[0002]

2. Description of the Related Art When vulcanizing natural rubber or synthetic rubber with an alkylphenol resin, a metal halide such as stannous chloride, ferric chloride or zinc chloride has conventionally been used as a vulcanization accelerator. , Chloroprene rubber (CR),
Organic halides such as chlorosulfonated polyethylene and chlorinated paraffin, and aromatic sulfonic acids such as p-toluenesulfonic acid are used.

[0003] However, the rubber product vulcanized with the alkylphenol resin in such a manner, when used for hoses, vibration-proof materials, various packing materials, sealing materials, etc., is used in a portion in contact with various metals and metal parts. In some cases, the corrosion of metal is accelerated, causing problems such as deterioration of surface appearance, reduction of strength, and increase of electric resistance. Also, when kneading a resin vulcanized rubber composition, corrosion of rolls, dies, and the like is a problem.

[0004] Although the cause is not always clear, it is considered that it is probably due to a halogen compound contained in the vulcanization accelerator. As a countermeasure, a method of preventing corrosion of a metal by applying a rust inhibitor to a metal portion, or performing vulcanization without using a vulcanization accelerator is employed. However, depending on the type of kneading machine and the part of the rubber product used, it may not be possible to use a rust preventive agent. Condition.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a resin vulcanized rubber composition using an alkylphenol resin, in which it is not necessary to apply a rust inhibitor to a metal part in contact with the resin and the vulcanization rate is high. It is to provide a rubber composition. The present inventors have conducted intensive studies and found that, when vulcanizing rubber with an alkylphenol resin, an aromatic sulfonic acid having a specific substituent is used instead of a conventional vulcanization accelerator or vulcanization catalyst. The present inventors have found that a resin vulcanized rubber composition which does not exhibit a metal corrosion action while maintaining a high sulfuric acid rate can be obtained, thereby completing the present invention.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a resin vulcanized rubber composition comprising a natural rubber or a synthetic rubber and an alkylphenol resin, which has 2 to 30 carbon atoms as a vulcanization accelerator.
A vulcanized resin composition comprising an aromatic sulfonic acid having an alkyl group as described below.

[0007] In a preferred embodiment of the present invention, 1 to 25 parts by weight of an alkylphenol resin as a vulcanizing agent and 2 to 30 carbon atoms of an alkyl group having 2 to 30 carbon atoms as a vulcanization accelerator, based on 100 parts by weight of natural rubber or synthetic rubber. And v. 0.01 to 50 parts by weight of aromatic sulfonic acids having the formula (1).

[0008] The resin vulcanized rubber composition of the present invention can be directly used as a rubber product, but a general-purpose rubber is added to an alkylphenol resin in advance, and if necessary, a filler,
A softener and other additives may be added, kneaded and used as a so-called master batch.

Specific examples of the natural or synthetic rubber used in the present invention include natural rubber (NR), styrene butadiene rubber (SBR), butadiene rubber (BR), nitrile rubber (NBR), and butyl rubber. (II
R), ethylene-propylene-terpolymer (EPD)
M) etc. can be raised. Among these, butyl rubber (IIR) is particularly preferably used.

The alkylphenol resin referred to in the present invention is specifically an alkylphenol obtained by condensation of a phenol having an alkyl group having 1 to 18 carbon atoms (substituted with a meta- and / or para-alkyl group) with formaldehyde. Resins are preferred.

The phenol having an alkyl group having 1 to 18 carbon atoms, which is a raw material of the alkylphenol resin, is specifically, for example, p-cresol, i-
Examples include propylphenol, pt-butylphenol, amylphenol, pt-octylphenol, nonylphenol, dodecylphenol, allylphenol, cyclohexylphenol, 4,6-dioctylresorcinol, and the like. Of these, p
-T-butylphenol, amylphenol, pt-
Octylphenol is preferably used. As such an alkylphenol resin, for example, a resin commercially available as Tackirole (trade name, manufactured by Taoka Chemical Industry Co., Ltd.) 201 or the like is used.

The aromatic sulfonic acid having an alkyl group having 2 to 30 carbon atoms as the vulcanization accelerator used in the present invention is preferably an aromatic sulfonic acid having an alkyl group having 5 to 20 carbon atoms, Specifically, p-ethylbenzenesulfonic acid, pn-propylbenzenesulfonic acid, p-isopropylbenzenesulfonic acid, pt-butylbenzenesulfonic acid, p-amylbenzenesulfonic acid, pt-octylbenzenesulfonic acid , P-dodecylbenzenesulfonic acid and the like, which are used alone or in combination. These aromatic sulfonic acids include, for example, Neoperex FS (trade name of Kao Corporation)
Alkyl benzene sulfonic acid commercially available as is preferably used.

In the resin vulcanized rubber composition of the present invention, an alkylphenol resin for natural rubber or synthetic rubber,
The amount of the vulcanization accelerator to be added is appropriately determined depending on the desired degree of vulcanization and the purpose of use.When the resin vulcanized rubber composition is vulcanized as it is and used as a rubber product,
Based on 100 parts by weight of natural rubber or synthetic rubber, 1 to 25 parts by weight, preferably 5 to 20 parts by weight, of an alkylphenol resin as a vulcanizing agent and 2 to 2 carbon atoms as a vulcanization accelerator.
Aromatic sulfonic acids having 30 alkyl groups 0.01
To 50 parts by weight, preferably 0.1 to 20 parts by weight.

The resin vulcanized rubber composition of the present invention further comprises a filler or a softening agent, if necessary. Usually, in order to facilitate compounding, it is preferable to use a filler or a softener in combination for other purposes.

Examples of the filler used in the present invention include carbon black, calcium carbonate, clay, silica, calcium silicate, magnesium silicate, talc, zinc oxide, magnesium oxide, titanium white and the like. The mixing ratio of these fillers is 1 to 200 parts by weight, preferably 10 to 150 parts by weight, based on 100 parts by weight of natural rubber or synthetic rubber, and these may be used alone or as a mixture.

Examples of the softener used in the present invention include fatty acids, naphthenic process oils, paraffinic process oils, aromatic process oils, waxes and the like. Here, as the fatty acids, for example, stearic acid and oleic acid are used, and as the naphthenic process oil, for example, Comolex No. 2, PW-
90, etc., and further as a paraffinic process oil,
For example, paraffin wax etc. can be mentioned as sumpers 107, -115, -150 and waxes. The mixing ratio of these softeners is 0 to 150 parts by weight, preferably 1 to 100 parts by weight of natural rubber or synthetic rubber.
８０80 parts by weight.

In the method for producing the resin vulcanized rubber composition of the present invention, a rubber component, an alkylphenol resin, a vulcanization accelerator and other compounding agents may be kneaded at the same time or mixed or kneaded with a specific component in advance. Then, it may be mixed or kneaded with other components. For example, after preparing a mixture of an alkylphenol resin and a vulcanization accelerator, a rubber component, an alkylphenol resin, a mixture of three components of a vulcanization accelerator, and the like in advance, the composition of the present invention may be obtained as a final composition. . The mixing or kneading temperature of the vulcanization accelerator and other components is preferably in the range of 0 to 150C. If the temperature is too low, uniform mixing may be difficult. On the other hand, if the temperature is too high, the reaction proceeds before vulcanization of the rubber, which tends to cause problems in vulcanization molding of the rubber.

Examples of the master batch containing a so-called vulcanization accelerator include, for example, a hermetic sealant capable of heating and cooling the vulcanization accelerator, the alkylphenol resin, the natural rubber or the synthetic rubber, and, if necessary, a filler and a softening agent. Put into a formula kneader and set the internal temperature to 30-100 ° C, preferably 6
It can be easily obtained by mixing and homogenizing while maintaining the temperature at 0 to 80 ° C., and taking out a sheet or forming a pellet according to the application.

[0019]

According to the present invention, the resin vulcanized rubber composition maintains a preferable vulcanization rate, and the vulcanization accelerating catalyst hardly bleeds to the surface after vulcanization, and remarkable improvement in corrosiveness to metal is recognized. .

[0020]

EXAMPLES Examples 1 to 3 and Comparative Examples 1 and 2 Kneading was carried out using a 6-inch roll to prepare a base rubber according to the following formulation. IIR (Butyl 402: trade name of Policer) 100 parts by weight Stearic acid 1 part by weight HAF carbon (manufactured by Asahi Carbon Co.) 50 parts by weight ───────────────────── ─────────── Total 151 parts by weight

The base rubber is divided and charged into a 6-inch roll.
1, Taoka Chemical Industry Co., Ltd.) (13 parts by weight) and a predetermined amount of a vulcanization accelerator described in Table 1 were added and kneaded to prepare a resin vulcanized rubber composition. The obtained resin vulcanized rubber composition,
ASTM D-2 using an oscillating disc rheometer (ASTM-100 manufactured by Toyo Seiki Seisaku-sho, Ltd.)
The vulcanization characteristics were measured according to No. 084. The results are shown in Table 1.

A bleed test was performed on each sample, and the results are shown in Table 1. The bleed test was performed by the following method. The rubber of each sample was vulcanized (temperature 18
(0 ° C., 45 minutes), and after standing for one week, the rubber surface was visually observed. Next, 20 g of the vulcanized rubber was cut (about 40 pieces) and
The resulting mixture was charged into 00 g, kept at 50 ° C. for 36 hours, cooled to 20 ° C., and then the pH of water was measured.

[0023]

[Table-1]

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 61/06 C08L 61/06 // (C08L 7/00 61:06) (C08L 21/00 61:06) (C08L 23 / 22 61:06)

Claims (3)

[Claims] 1. A resin vulcanized rubber composition comprising a natural rubber or a synthetic rubber and an alkylphenol resin, comprising an aromatic sulfonic acid having an alkyl group having 2 to 30 carbon atoms as a vulcanization accelerator. Characterized resin vulcanized rubber composition. 2. An aromatic sulfonic acid having 1 to 25 parts by weight of an alkylphenol resin and 0.01 to 50 parts by weight of an aromatic sulfonic acid having an alkyl group having 2 to 30 carbon atoms as a vulcanization accelerator, based on 100 parts by weight of natural rubber or synthetic rubber. And a resin vulcanized rubber composition. 3. The natural rubber or the synthetic rubber is composed of butyl rubber.
The resin vulcanized rubber composition according to claim 1, which is a rubber containing 0% by weight or more.