Abstract: Provided is a pneumatic tire which comprises a pair of left and right bead portions, sidewall portions continuous from the bead portions, and a tread portion that couples the sidewall portions. The pneumatic tire has a carcass layer mounted between the left and right bead portions. The sidewall portions each have a foamed rubber layer disposed outside the carcass layer and a side rubber layer disposed outside the foamed rubber layer. The density of the foamed rubber layer is from 0.5 to 0.9 g/cm3 and a tan ? of the foamed rubber layer at 20° C. is not greater than 0.17. A rubber composition for sidewalls that forms the side rubber layer is obtained by blending from 1 to 20 parts by weight of a thermoplastic resin and from 10 to 65 parts by weight of a carbon black in 100 parts by weight of a diene rubber.

Abstract: The present invention provides a rubber composition and a tire, which provides superior wear resistance and processability while maintaining the wet performance. The present invention provides a rubber composition for a tire including a rubber component including a modified diene rubber with carboxy group modification, silica and a predetermined polysiloxane; wherein the content of the silica is from 60 to 200 parts by mass per 100 parts by mass of the rubber component, the content of the polysiloxane is from 1 to 20 mass % based on the content of the silica, and the content of the modified diene rubber is from 10 to 100 parts by mass per 100 parts by mass of the rubber component. The present invention also provides a tire using the rubber composition.

Abstract: A process for producing a modified polymer having, in the molecule thereof, an organic group(s) introduced thereinto and derived from a compound(s) having a free radical comprising reacting a polymer such as an elastomer with a compound having the free radical stable at an ordinary temperature in the presence of oxygen, after or while a carbon radical(s) is generated in the polymer, whereby the modified polymer having an improved bondability and processability is formed.

Abstract: A process for producing a modified polymer having, in the molecule thereof, an organic group(s) introduced thereinto and derived from a compound(s) having a free radical comprising reacting a polymer such as an elastomer with a compound having the free radical stable at an ordinary temperature in the presence of oxygen, after or while a carbon radical(s) is generated in the polymer, whereby the modified polymer having an improved bondability and processability is formed.

Abstract: A process for producing a modified polymer having, in the molecule thereof, an organic group(s) introduced thereinto and derived from a compound(s) having a free radical comprising reacting a polymer such as an elastomer with a compound having the free radical stable at an ordinary temperature in the presence of oxygen, after or while a carbon radical(s) is generated in the polymer, whereby the modified polymer having an improved bondability and processability is formed.

Abstract: A pneumatic tire is disclosed, which comprises a bubble-containing adhesive composition layer as a puncture prevention layer or a puncture prevention layer formed by covering at least one surface of a sheet-like foamed body with a nonporous adhesive composition layer, disposed in the inner surface of a tire main body. This pneumatic tire having the puncture prevention layer in the tire inner surface is adapted to reduce the weight of the tire.

Abstract: A silica-polymer composite, featuring a low viscosity and excellent processability when being kneaded with a rubber and superior in dispersibility and tensile strength, comprising a polymer having a polar group containing a hetero atom and a benzene ring or a polymer having a carboxylic acid reacted with silica in a solution.

Abstract: A rubber composition containing 50 to 90 parts by weight of a diene rubber and 50 to 10 parts by weight of a gelled rubber having a toluene swelling index of 16 to 150, based upon the total amount of 100 parts by weight of the diene rubber and the gelled rubber.

Abstract: A modified polybutene(polyisobutylene) containing isobutylene repeating units and having, in the main chain, at the ends, and/or at the side chains of the polymer chain thereof, free radicals stable at a room temperature and in the presence of oxygen, or having a half-ester structure, amide structure, onium salt structure, or imide structure or acid anhydride residual group, as well as a rubber composition containing the same.

Abstract: A pneumatic tire is disclosed, which comprises a bubble-containing adhesive composition layer as a puncture prevention layer or a puncture prevention layer formed by covering at least one surface of a sheet-like foamed body with a nonporous adhesive composition layer, disposed in the inner surface of a tire main body. This pneumatic tire having the puncture prevention layer in the tire inner surface is adapted to reduce the weight of the tire.

Abstract: To provide a rubber vulcanizing agent able to prevent a reduction in the various physical properties of a vulcanized rubber after aging and possible to suppress scorching due to premature vulcanization or reversion and a rubber composition containing the same. A rubber vulcanizing agent having at least two thiirane groups in the molecule thereof and a rubber composition containing this rubber vulcanizing agent and a thiirane ring-opening agent.

Abstract: Rubber compositions for footwear, conveyor belt covers, rolls, hoses, cables, rubberized fabrics, and grips containing (A) an elastomer, (B) 5 to 150 parts by weight of a filler, and (C) a polysiloxane represented by the formula (I): wherein R1, R2, R3, m, and n are as defined in the specification, having an average degree of polymerization of 3 to 1000 in a specific ratio with respect to the filler (B) and footwear, conveyor belt covers, rolls, hoses, cables, rubberized fabrics, and grips comprising these rubber compositions.