The present technology provides a rubber composition wherein from 1 to 100 parts by mass of carbon black and/or from 10 to 150 parts by mass of inorganic filler, from 1 to 30 parts by mass of sulfur-containing compounding agent, and from 0.1 to 20 parts by mass of tin oxide compound, are blended per 100 parts by mass of sulfur-crosslinkable diene rubber; and a pneumatic tire that uses this rubber composition in a cap tread.

The present technology provides a rubber composition wherein from 1 to 100 parts by mass of carbon black and/or from 10 to 150 parts by mass of inorganic filler, from 1 to 30 parts by mass of sulfur-containing compounding agent, and from 0.1 to 20 parts by mass of tin oxide compound, are blended per 100 parts by mass of sulfur-crosslinkable diene rubber; and a pneumatic tire that uses this rubber composition in a cap tread.

A methacrylic resin composition comprises a methacrylic resin, the methacrylic resin comprising: 50 mass % to 97 mass % of a methacrylic acid ester monomer unit (A); 3 mass % to 30 mass % of a structural unit (B) having a cyclic structure-containing main chain; and 0 mass % to 20 mass % of another vinyl monomer unit (C) that is copolymerizable with a methacrylic acid ester monomer, wherein the methacrylic resin satisfies a specific condition; and the composition has a weight average molecular weight residual ratio of 80% or more upon heating under a nitrogen atmosphere at 280° C. for 1 hour, and has a weight average molecular weight residual ratio of 80% or more upon heating in air at 280° C. for 0.5 hours.

A methacrylic resin composition comprises a methacrylic resin, the methacrylic resin comprising: 50 mass % to 97 mass % of a methacrylic acid ester monomer unit (A); 3 mass % to 30 mass % of a structural unit (B) having a cyclic structure-containing main chain; and 0 mass % to 20 mass % of another vinyl monomer unit (C) that is copolymerizable with a methacrylic acid ester monomer, wherein the methacrylic resin satisfies a specific condition; and the composition has a weight average molecular weight residual ratio of 80% or more upon heating under a nitrogen atmosphere at 280° C. for 1 hour, and has a weight average molecular weight residual ratio of 80% or more upon heating in air at 280° C. for 0.5 hours.

Copolymers having General Formula (I):

##STR00001##

in which R.sup.1 is chosen from divalent C.sub.4-C.sub.7 aliphatic groups and divalent C.sub.4-C.sub.7 heteroaliphatic groups, optionally substituted with one or more C.sub.1-C.sub.6 aliphatic groups, heteroatoms independently chosen from O, N, and S, or combinations thereof, where: the divalent C.sub.4-C.sub.7 heteroaliphatic groups include one or two heteroatoms independently chosen from O, N, and S, and the maximum number of heteroatoms in R.sup.1 is two; x is a molar fraction range chosen from 0.05 to 0.95; and y is a molar fraction range chosen from 0.05 to 0.95, where the summation of x and y equals 1. Methods for inhibiting formation of clathrate hydrates in a fluid capable of forming the clathrate hydrates. The methods include contacting the fluid with at least one copolymer of General Formula (I) under conditions suitable for forming the clathrate hydrates.

Copolymers having General Formula (I):

##STR00001##

in which R.sup.1 is chosen from divalent C.sub.4-C.sub.7 aliphatic groups and divalent C.sub.4-C.sub.7 heteroaliphatic groups, optionally substituted with one or more C.sub.1-C.sub.6 aliphatic groups, heteroatoms independently chosen from O, N, and S, or combinations thereof, where: the divalent C.sub.4-C.sub.7 heteroaliphatic groups include one or two heteroatoms independently chosen from O, N, and S, and the maximum number of heteroatoms in R.sup.1 is two; x is a molar fraction range chosen from 0.05 to 0.95; and y is a molar fraction range chosen from 0.05 to 0.95, where the summation of x and y equals 1. Methods for inhibiting formation of clathrate hydrates in a fluid capable of forming the clathrate hydrates. The methods include contacting the fluid with at least one copolymer of General Formula (I) under conditions suitable for forming the clathrate hydrates.

Processes for forming a vulcanizable elastomeric formulation are disclosed. The processes include the steps of mixing an elastomer with a vulcanizing agent to form a vulcanizable elastomeric formulation that includes the vulcanizing agent dispersed in the elastomeric compound, wherein the vulcanizing agent includes a cyclododecasulfur compound. A process for forming a vulcanized elastomeric article is also described.

Processes for forming a vulcanizable elastomeric formulation are disclosed. The processes include the steps of mixing an elastomer with a vulcanizing agent to form a vulcanizable elastomeric formulation that includes the vulcanizing agent dispersed in the elastomeric compound, wherein the vulcanizing agent includes a cyclododecasulfur compound. A process for forming a vulcanized elastomeric article is also described.

Provided are a rubber composition having a good balance of improved fuel efficiency, abrasion resistance, and wet grip performance while providing good processability, and a pneumatic tire having a tread manufactured from the rubber composition. A rubber composition comprising: a copolymer synthesized by copolymerization of a conjugated diene monomer and an unsaturated acyclic monoester represented by the formula (1) below; and carbon black and/or silica, ##STR00001##
wherein R.sup.1 represents hydrogen or a C1-C30 hydrocarbon group, and R.sup.2 represents hydrogen or a C1-C30 hydrocarbon group.

Embodiments of organic peroxide formulations provide significant improvements in surface tackiness (often including tack-free surfaces) when curing elastomers in the presence of oxygen. The peroxide formulations may include, for example, one or more compounds selected from sulfur-containing compounds, organophosphite compounds, HALS (Hindered Amine Light Stabilizer) compounds, aliphatic allyl urethane compounds, and blends comprising nitroxides (e.g., 4-hydroxy-TEMPO) and quinones (e.g., mono-tert-butylhydroquinone).