Crumb rubber obtained from recycled tires is subjected to an interlinked substitution process. The process utilizes a reactive component that interferes with sulfur bonds. The resulting treated rubber exhibits properties similar to those of the virgin composite rubber structure prior to being granulated, and is suitable for use in fabricating new tires, engineered rubber articles, and asphalt rubber for use in waterproofing and paving applications.

Disclosed are a water-expandable rubber composition and a water-expandable rubber pad including the same. The water-expandable rubber pad manufactured using the water-expandable rubber composition is rigid enough to be directly inserted into a cylinder jacket even without a metal plate, etc. Moreover, the water-expandable rubber pad may increase in volume upon contact with engine coolant, thereby being optimized for an assembly process and facilitating design. Thus, since no separate assembly parts are used compared to conventional cases, the number of parts can be reduced, and costs can be reduced, and adhesiveness of the rubber pad is superior to that of conventional foam rubber and thus heat retention performance is excellent, resulting in improved engine fuel efficiency.

Disclosed are a water-expandable rubber composition and a water-expandable rubber pad including the same. The water-expandable rubber pad manufactured using the water-expandable rubber composition is rigid enough to be directly inserted into a cylinder jacket even without a metal plate, etc. Moreover, the water-expandable rubber pad may increase in volume upon contact with engine coolant, thereby being optimized for an assembly process and facilitating design. Thus, since no separate assembly parts are used compared to conventional cases, the number of parts can be reduced, and costs can be reduced, and adhesiveness of the rubber pad is superior to that of conventional foam rubber and thus heat retention performance is excellent, resulting in improved engine fuel efficiency.

Disclosed are a liquid hydrogenated nitrile-butadiene rubber, a preparation method therefor and the use thereof. In the liquid hydrogenated nitrile-butadiene rubber: the content of acrylonitrile is 15-50%; the hydrogenation saturation is 75-99.5%; the weight-average molecular weight (Mw) is 3,000-60,000; the molecular weight polydispersity index (PDI) is 2.0-8.0; and the glass transition temperature (Tg) is lower than −28° C. The liquid hydrogenated nitrile-butadiene rubber is low in molecular weight and wide in molecular weight polydispersity, simultaneously has an excellent fluidity during processing and excellent mechanical properties after curing and has a unique application value in the field of special rubbers; and the preparation method therefor is simple and feasible in terms of the process.

This invention relates to novel hydrogenation catalyst compositions obtainable from reacting metal-based complex hydrogenation catalysts with specific co-catalysts and to a process for selectively hydrogenating nitrile rubbers in the presence of such novel hydrogenation catalyst compositions.

Provided is a composition for a gas seal member that can form a gas seal member for a high-pressure hydrogen device that is capable of sufficiently inhibiting both swelling destruction and blister destruction. The composition for a gas seal member is a composition for a gas seal member used in a high-pressure hydrogen environment and contains an elastomer and fibrous carbon nanostructures. The fibrous carbon nanostructures are contained in a proportion of not less than 1 part by mass and not more than 10 parts by mass per 100 parts by mass of the elastomer. An area fraction S (%) of aggregates of the fibrous carbon nanostructures in a cross-section of the composition for a gas seal member and a volume percentage V (volume %) of the fibrous carbon nanostructures in the composition for a gas seal member satisfy a relationship 0≤S/V≤2.0.

The residual hydrogenation catalyst from the hydrogenated nitrile rubber solution is recovered by using two steps such as (1) the catalyst extraction step with an ammonium salt and water (optionally including an oxidation step) to extract catalyst from the HNBR polymer chain to the solvent and then (2) the separation/column recovery step with the column packed with functional ion exchange resins for the separation of ammonia-catalyst complex from hydrogenated nitrile rubber solution and the column recovery for the high catalyst recovery with functional groups of resins. The ammonium salt for the catalyst extraction step is selected from ammonium chloride, ammonium bromide, ammonium iodide, and ammonium acetate. The functional groups in the functional ion exchange resins for packing the column is selected from thiourea, thiouronium, thiol, amine, diamine, triamine, TMT, dithiocarbamate, and carbodithioate.

Lubricity of a lip seal material using hydrogenated nitrile rubber is improved. A rubber-like elastic lip seal which is fixed to a housing and slides with a shaft that rotates relatively with the housing, wherein the lip seal includes a rubber-like elastic body containing hydrogenated nitrile rubber, EPDM or fluoro rubber, a reinforcing filler material, and a non-reinforcing filler material having an aspect ratio in a range of 1 or more and 30 or less, and the lip seal contains 1 part by weight or more and 150 parts by weight or less of the reinforcing filler material and 5 parts by weight or more and 90 parts by weight or less the non-reinforcing filler material per 100 parts by weight of the rubber-like elastic body.

Lubricity of a lip seal material using hydrogenated nitrile rubber is improved. A rubber-like elastic lip seal which is fixed to a housing and slides with a shaft that rotates relatively with the housing, wherein the lip seal includes a rubber-like elastic body containing hydrogenated nitrile rubber, EPDM or fluoro rubber, a reinforcing filler material, and a non-reinforcing filler material having an aspect ratio in a range of 1 or more and 30 or less, and the lip seal contains 1 part by weight or more and 150 parts by weight or less of the reinforcing filler material and 5 parts by weight or more and 90 parts by weight or less the non-reinforcing filler material per 100 parts by weight of the rubber-like elastic body.

The present invention is to provide a rubber composition for a hose and the like, the rubber composition having excellent oil resistance and low-temperature performance. A rubber composition for a hose, the rubber composition comprising: a hydrogenated acrylonitrile butadiene rubber having an acrylonitrile amount of 24 mass % or less, a carbon black, a peroxide, and a triallyl isocyanurate; a content of the peroxide being 2.4 parts by mass or more per 100 parts by mass of the hydrogenated acrylonitrile butadiene rubber; and a content of the triallyl isocyanurate being 1.9 parts by mass or more per 100 parts by mass of the hydrogenated acrylonitrile butadiene rubber, and a hose formed by using the rubber composition for a hose.