JPH0192253A - rubber composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a rubber composition, and more particularly to a composition comprising butyl rubber and/or halogenated butyl rubber and epichlorohydrin rubber having improved mechanical properties.

(Prior art) Butyl rubber and halogenated butyl rubber have been known as rubbers with extremely high gas permeability and excellent vibration damping properties, but because of their poor oil resistance, they usually do not come into contact with various oils. It has never been used in oil-resistant rubber parts. In addition, epichlorohydrin rubber has excellent oil resistance and gas permeability.
Its performance was insufficient for parts that required a high degree of gas permeability, and it was never used.

Incidentally, as various industrial fields have become more sophisticated in recent years, there has been a demand for base materials such as oil-resistant rubber with excellent gas permeability and oil-resistant rubber with excellent anti-vibration properties.

To achieve this purpose, there are methods of developing new rubbers, methods of blending rubbers, and methods of improving them by compounding. However, there is a problem in that it usually takes a long time to develop a new rubber, and there is a natural limit to the development of properties when improving the rubber by compounding.

Up to now, butyl rubber or halogenated butyl rubber and epichlorohydrin rubber have not been used as a blend. The reason for this is that butyl rubber or halogenated butyl rubber and epichlorohydrin rubber have poor compatibility, poor miscibility and dispersibility, and difficulty in co-vulcanization.

Therefore, depending on the co-vulcanization method commonly used in the rubber industry, the mechanical properties of a blended rubber vulcanizate of butyl rubber or halogenated butyl rubber and epichlorohydrin rubber decrease as the blend ratio approaches equal volumes. However, there is a drawback that the method is slow, and improvements in this area are desired.

(Problems to be Solved by the Invention) The present inventors have conducted intensive research to improve the physical properties of vulcanizates of blend rubber compositions of butyl rubber or halogenated butyl rubber and epichlorohydrin rubber. It was discovered that excellent mechanical properties can be developed by modifying either or both of dibutyl rubber and epichlorohydrin rubber with maleic anhydride or its derivatives, and based on this knowledge, the present invention was completed. I ended up doing it.

(Means for Solving the Problems) Thus, according to the present invention, based on the rubber before modification, (1) at least one of butyl rubber and halogenated butyl rubber in an amount of 10 to 90 weight percent as the first rubber component; (2) Epichlorohydrin rubber 90 as the second rubber component
-10% by weight, and contains at least 1% by weight of at least one of the above-mentioned rubber components modified with maleic anhydride or a derivative thereof in the total rubber components.

The butyl rubber and isobutylene-isoprene copolymer rubber (IIR) used as the first rubber component in the present invention usually have an unsaturation degree of 0.5 to 2.5 mol%, and the above-mentioned butyl rubber is used as the halogenated butyl rubber. Examples include chlorinated or brominated chlorinated butyl rubber (CIIR) and brominated butyl rubber (BrllR).

Epichlorohydrin rubber as the second rubber component in the present invention is a homopolymer rubber of shrimp chlorohydrin (CO
), shrimp chlorohydrin-ethylene oxide copolymer rubber (ECO), shrimp chlorohydrin-allyl glycidyl ether copolymer rubber, shrimp chlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer rubber (ETCO), and shrimp chlorohydrin-propylene oxide-allyl glycidyl ether terpolymer rubber, etc., and further, these rubbers and a number average molecular weight of 10.0.
Blends of liquid polymer rubbers with the above compositions below 0.00 are also included in the present invention.

Butyl rubber, halogenated butyl rubber, or epichlorohydrin rubber modified with maleic anhydride or its derivatives used in the present invention can be obtained by directly thermally modifying the unmodified rubber with maleic anhydride or its derivatives at high temperature, or by radical treatment. A method of radical modification in the presence of a generator is used. The direct heat modification method and the radical modification method are performed by heating butyl rubber, halogenated pulti rubber, or epichlorohydrin rubber and maleic anhydride or a derivative thereof in an inert solvent that dissolves them, or by heating the polymer rubber and maleic anhydride. This is a method of denaturing a mixture of acids or their derivatives by heating them. For example, when the modification reaction is carried out in a solution, it can be carried out in a chemical reaction vessel such as an autoclave, and when the reaction is carried out in a solid phase, it can be carried out using a mixing processing machine such as an internal kneader, a kneading extruder, or a roll.

Maleic anhydride and its derivatives used in the present invention include maleic anhydride, maleic acid, monoalkyl maleate such as maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid monobutyl ester, maleic acid mono-2-ethylhexyl ester, etc. These include esters, maleimides, maleimides such as N-hydroxyethylmaleimide, and the like.

In the case of the present invention, there is no particular restriction on the amount of modification of maleic anhydride or its derivatives into butyl rubber, halogenated butyl rubber, or epichlorohydrin rubber (the amount of bonding reaction to the rubber), but preferably with respect to the polymer rubber. Maleic anhydride or a derivative thereof has a molecular weight of I x 10-'' mole ffi/100g rubber or more.In the present invention, there is no restriction on the molecular weight of the modified rubber.It is preferably a weight average molecular weight of 3,000 or more. .

Further, in the present invention, the object can be achieved by containing at least one of the first rubber component and the second rubber component modified with maleic anhydride or a derivative thereof in an amount of 1% by weight or more in the total rubber component. Preferably it is 2% by weight or more.

The rubber composition in the present invention contains 10 to 90% by weight of the first rubber component and the second rubber component, based on the rubber before modification.
It consists of a rubber component of 90 to 10% by weight. If the first rubber component is less than 10% by weight and the second rubber component is 90% by weight or more, or if the first rubber component is 90% by weight or more and the second rubber component is less than 10% by weight, the first rubber component and the second rubber component are The excellent properties of each rubber, such as the balance between gas permeability and oil resistance, are not improved, and the characteristics of a blended rubber cannot be obtained. Preferred composition ratios are 30 to 70% by weight of the first rubber component and 70 to 30% by weight of the second rubber component.

In the present invention, the rubber standard before modification refers to the modified first rubber standard.
The rubber component (the number of parts used is A' by weight) or the second rubber component (the number of parts by weight is B') is regarded as the unmodified component rubber, and the unmodified first rubber component (the number of parts by weight is also B') is considered as the unmodified component rubber. A
(parts by weight) or added to the unmodified second rubber component (also 8 parts by weight), and 10 to 90% by weight of the first rubber component is the value determined by be.

The rubber composition of the present invention is characterized by containing the rubber component modified with maleic anhydride or a derivative thereof in the first rubber component and/or the second rubber component, thereby providing excellent mechanical properties for vulcanizates. It is the ability to express one's own characteristics.

There are no particular restrictions on the type and amount of the vulcanizing agent, vulcanization accelerator, and activator used in the present invention in order to express such properties, and the types and amounts normally used in the rubber industry can be used. . Preferably, metal oxides such as zinc oxide and magnesium oxide, sulfur-based vulcanizing agents, quinoid-based vulcanizing agents, methylolphenol-based vulcanizing agents, alkylphenol disulfide-based vulcanizing agents, thiourea-based vulcanizing agents, and triazinethiol-based vulcanizing agents. Vulcanizing agents, amine vulcanizing agents, polyfunctional epoxide compounds,
A polyfunctional isocyanate compound and a polyfunctional hydroxy compound may be used alone or in combination. Specific examples of these compounds include, for example, Rubber Digest Co., Ltd. Rubber/Plastic Compounded Chemicals (published in 1970, revised edition), Shinzo Yamashita, Tosuke Kaneko Crosslinking Agent Handbook (published in 1980, Taiseisha)
However, it goes without saying that the present invention is not limited to these described examples.

The rubber composition of the present invention is mixed with the above-mentioned vulcanization system and compounding agents using an ordinary mixer, and then formed into a predetermined shape using an ordinary rubber molding machine such as a roll, press molding machine, extrusion molding machine, or injection molding machine. Can be molded.

Compounding agents other than those mentioned above used in the present invention include reinforcing agents, fillers, plasticizers, softeners, processing aids, and
Anti-aging agents and the like can be used, and the type and amount are appropriately determined depending on the intended use of the rubber composition.

(Effects of the Invention) Thus, according to the present invention, the processability is significantly improved in mechanical properties compared to rubber compositions obtained by blending conventional butyl rubber and/or halogenated butyl rubber with epichlorohydrin rubber. A rubber composition with good properties is provided.

The rubber composition of the present invention can be molded and vulcanized to improve the permeation resistance of tire tubes, hoses, seals and gaskets, healds, boots, rolls, vibration-proof parts, and various gaseous components. Suitable for manufacturing various rubber parts, etc. that are required.

(Example) The present invention will be described in more detail with reference to Examples below. Note that parts and percentages in Examples and Comparative Examples are based on weight unless otherwise specified.

Examples 1 to 3, Comparative Examples 1 to 3 According to the formulations of the Examples and Comparative Examples shown in Table 1, Examples 1 to 3 and Comparative Examples 1 to 3 were prepared using a total of 100 parts of butyl rubber and modified butyl rubber, SRF carbon black 60
1 part, 3 parts of zinc oxide, 2 parts of tetramethylthiuram disulfide, and 2 parts of sulfur mixed on a low temperature roll, and 100 parts of shrimp chlorohydrin homopolymer rubber, S
60 parts of RF carbon black, 3 parts of magnesium oxide,
2.4.6- 1 part of trimercapto-8-triazine,
A rubber compound prepared by mixing 0.5 parts of diphenylguanidine and 4 parts of polyoxybucopylene diamine in the same manner,
The rubbers were mixed using a low-temperature roll to achieve the mixing ratio shown in Table 1. The obtained rubber compound composition was press-vulcanized at 160° C. for 30 minutes to obtain a vulcanized product.

Example 4 A rubber compounded composition was prepared in the same manner as in Examples 1 to 3, except that liquid shrimp chlorohydrin homopolymer rubber was added to shrimp chlorohydrin homopolymer rubber, and a vulcanizate was obtained.

Example 5 A product was prepared in the same manner as above except that chlorinated butyl rubber and modified chlorinated butyl rubber were added to the butyl rubber. Comparative Example 4 was prepared in the same manner except that chlorinated butyl rubber was added to the butyl rubber.

Examples 6-8, Comparative Examples 5-6 100 parts of chlorinated butyl rubber, SRF carbon black 6
A rubber compound prepared by mixing 0 parts of zinc oxide, 3 parts of methylolated alkylphenol formaldehyde resin, 0.6 parts of tetramethylthiuram disulfide and 0.4 parts of sulfur on a low temperature roll, and shrimp chlorohydrin-ethylene oxide-allyl glycidyl. Total of ether terpolymer rubber and modified shrimp chlorohydrin homopolymer rubber: 100
1 part, 60 parts of SRF carbon black, 3 parts of magnesium oxide, and 1 part of 2.4.6-1-rimerkabuto S-triazine were mixed in the same manner, and a rubber compound was prepared so that the rubber components had the mixing ratio shown in Table 1. After mixing with a low-temperature roll, press vulcanization was performed at 160° C. for 30 minutes to obtain a vulcanized product.

Regarding the vulcanizates of the above examples and comparative examples, JIS
A tensile test was conducted according to 6301. The result is the first
Also listed in the table.

(Note) ($1) Butyl 268° manufactured by Exxon ($2)
Chlorobutyl 1066° (*3) manufactured by Exxon Corporation Butyl 26B manufactured by Exxon Corporation 100 parts, maleic anhydride
Pour 2 parts into a Brabender mixer and mix at 180℃, 80℃.
After kneading for 10 minutes with rpa+, 2.5-dimethyl-2,5
-di(t-butylperoxy)hexyne-3 (Nippon Oil JI
Pour 0.1 part of KEXA 25B-40) into the bar made by M company,
The mixture was kneaded for 10 minutes and then discharged. The bound acid equivalent of the modified butyl rubber obtained was 3.6 x 10'' molar equivalent/100g rubber.

(Book 4) Chlorobutyl 1066100 manufactured by Exxon
1 part and 5 parts of maleic acid were put into a Brabender mixer, and a modified chlorinated butyl rubber was obtained using the same formulation as the modified butyl rubber described above. The binding acid equivalent is 1.5×10-” mole i
t/100g rubber.

(*5) Zekron 1000° manufactured by Nippon Zeon Co., Ltd. (book 6)
) Zekron 3103° manufactured by Nippon Zeon Co., Ltd. (Book 7) Hydrin 10×2, manufactured by Gutdrich Chemical Co., Ltd., number average molecular 113400° (Book 8) Zeklon 1000 manufactured by Nippon Zeon Co. 100 parts, and 3 parts maleic anhydride were mixed in a Brabender mixer. After kneading for 5 minutes at 150°C and 80 rpm+,
30.3 parts of dimethyl-2,5-di(t-butylperoxy)hexyne was added, kneaded for 30 minutes, and then discharged. The bound acid equivalent of the resulting modified epichlorohydrin homopolymer rubber was 1.3×10-'' molar equivalent/100 g rubber.

(Book 9) Jeffamine D- manufactured by Texaco Chemical Company
2000, average degree of polymerization 33, amine value 520゜hlO)
S P 1045 manufactured by Schenectady Company Table 1 Example 1 and Comparative Example 1, Example 2.4 and Comparative Example 2, Example 3 and Comparative Example 3, Example 5 and Comparative Example 4, and Example 6 A comparison of Comparative Example 5 and Example 7.8 with Comparative Example 6 shows that the composition of the present invention has significantly improved tensile strength and elongation over a wide blend composition range. In particular, when the blend ratio of butyl rubber or chlorinated butyl rubber and hydrin rubber is around 1:1, the tensile strength decreases significantly in the comparative examples, but as shown in the examples, the tensile strength decreases in the compositions of the present invention. It can be seen that the deterioration is significantly reduced and the strength is sufficient for practical use.

Sender: Zeon Corporation

Claims (1)

[Scope of Claims] Based on the rubber before modification, (1) 10 to 90% by weight of at least one of butyl rubber and halogenated butyl rubber as a first rubber component, and (2) epichlorohydrin rubber as a second rubber component. 90
-10% by weight, and contains at least 1% by weight of at least one of the above-mentioned rubber components modified with maleic anhydride or a derivative thereof in the total rubber components.