A polymer composition may include an ethylene vinyl acetate (EVA) polymer at an amount ranging from 10 to 90 phr; an elastomeric EVA composition at an amount ranging from 10 to 90 phr; a plasticizer at an amount ranging from 5 to 40 phr; a blowing agent in an amount ranging from 2 to 10 phr; and a peroxide in an amount ranging from 0.3 to 4 phr.

As the sealant material composition forming a sealant layer of a pneumatic tire provided with the sealant layer on a tire inner surface, the sealant material composition prepared by blending from 0.1 parts by mass to 20 parts by mass of a crosslinking agent, from 0.1 parts by mass to 40 parts by mass of an organic peroxide, and from 10 parts by mass to 400 parts by mass of a liquid polymer per 100 parts by mass of a butyl rubber is used.

There are provided a tire that combines a low elastic modulus at low temperatures with a high hysteresis loss at low temperatures and has excellent on-ice brake performance, and a vulcanized rubber and a rubber composition from which the tire is obtained. A rubber composition comprising a rubber component comprising a natural rubber, a polybutadiene rubber, and a styrene-butadiene copolymer rubber, and 50 to 90 parts by mass of a filler comprising silica relative to 100 parts by mass of the rubber component, wherein the mass n of the natural rubber in the rubber component is 40% by mass or more, the mass n, the mass b of the polybutadiene rubber, and the mass s of the styrene-butadiene copolymer rubber satisfy the relation: sbn, provided that when n=b, s<b, and 50% by mass or more of the silica is comprised in a phase comprising the polybutadiene rubber and the styrene-butadiene copolymer rubber.

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.

Provided is a rubber composition that can improve the on-ice performance of a rubber article such as a tire while maintaining the wear resistance of the rubber article at a good level. The rubber composition contains a rubber component and fibrous or flat particles, where the particles form a plurality of aggregates in the rubber composition, and a proportion of aggregate having an aggregation diameter of 10 m or more and 1000 m or less is 70% or more among the plurality of aggregates.

There is disclosed an elastomeric styrenic block copolymer (SBC) composition comprising one or more SBCs and one or more polymers miscible with styrenic end blocks of the one or more SBCs; wherein said block copolymer composition is both physically and chemically crosslinked; wherein said chemical crosslinking comprises covalent bonds between chains of SBC and; wherein said physical crosslinking comprises non-covalent interaction between styrenic end blocks of the one or more SBCs and the one or more polymers miscible with the styrenic end blocks.

Also disclosed is a miscible polymer blend comprising one or more SBCs and one or more polymers miscible with styrenic end blocks of the one or more SBCs; wherein said miscible polymer blend is both physically and chemically crosslinked; wherein said chemical crosslinking comprises covalent bonds between chains of SBC and; wherein said physical crosslinking comprises non-covalent interaction between styrenic end blocks of the one or more SBCs and the one or more polymers miscible with the styrenic end blocks.

The herein disclosed unique compositions or blends comprising physically and chemically cross-linked styrene block copolymers find use in, for example, the manufacture of thin-walled dipped articles such as condoms or gloves. The unique compositions or blends overcome the shortcoming of chemical resistance in presently available SBCs while maintaining a high level of mechanical resistance and flexibility.

Provided in the present invention is a rubber composition for tires which is improved in a dispersibility of silica in a rubber blended with a large amount of silica having so far made it difficult to be kneaded with the rubber and which makes it possible to carry out simultaneously using silica having a large particle diameter and blending a large amount of silica. Used in the present invention is a rubber composition for tires comprising a natural rubber and/or diene base rubber component, a glycerin fatty acid ester composition containing glycerin fatty acid monoester, and silica, wherein a BET specific surface area of the silica is 100 m.sup.2/g or more and 130 m.sup.2/g or less, and the rubber composition for tires contains 80 parts by mass or more of the silica based on 100 parts by mass of the rubber component. A tire produced by using the above rubber composition for tires has made it possible to allow a WET performance and a gripping performance to be consistent with an abrasion resistance and has made it possible as well to secure a processability in production by a reduction in a viscosity.

A vulcanizate prepared by a method including introducing an elastomer, a filler, and a mercapto-functional siloxane to form a masterbatch, where the mercapto-functional siloxane is selected from the group consisting of poly(dimethylsiloxane-co-mercaptopropylmethylsiloxane) and dimethoxy mercapto propyl terminated siloxanes, introducing a curative to the masterbatch to form a vulcanizable composition, and subjecting the vulcanizable composition to curing conditions.

A tire is provided with an external sidewall, said external sidewall comprising at least one elastomeric composition based on: (a) an elastomeric matrix comprising at least one diene elastomer, (b) a crosslinking system, and (c) at least one polymer incompatible with the elastomeric matrix. A process for the preparation of an elastomeric composition for an external sidewall is also disclosed.

Disclosed herein are rubber compositions comprising: (a) natural rubber, polyisoprene, or a combination thereof; (b) at least one conjugated diene monomer containing polymer or polymer; (c) a first silica filler having a BET surface area of at least 220 m.sup.2/g; (d) a second silica filler having a BET surface area lower than that of the first silica filler and greater than 135 m.sup.2/g; and (e) optionally carbon black filler.