This invention relates to sulfur, vulcanization accelerator and carbon black master batch formulations comprising either a semi-crystalline propylene-olefin copolymer or a combination of a semi-crystalline propylene-olefin copolymer and a hydrocarbon resin. The semi-crystalline propylene-olefin copolymer or the combination of semi-crystalline propylene-olefin copolymer and hydrocarbon resin imparts a high hardness property to the carbon black, sulfur and accelerator master batch formulations thereby preventing pellet agglomeration during storage and allowing for ease in material handling.

The invention provides a heavy-duty tire rubber composition excellent in wet grip performance and steering stability, and a tire tread, a bead filler, a tire belt and a heavy-duty tire which each partially include the composition. The heavy-duty tire rubber composition includes 100 parts by mass of a solid rubber (A), 0.1 to 50 parts by mass of a modified liquid diene rubber (B) having a functional group derived from a silane compound with a specific structure, and 20 to 200 parts by mass of a filler (C), the modified liquid diene rubber (B) satisfying the following (i) and (ii): (i) the weight average molecular weight (Mw) is not less than 1,000 and not more than 120,000, and (ii) the vinyl content is not less than 30 mol % and less than 70 mol %.

The invention provides a heavy-duty tire rubber composition excellent in wet grip performance and steering stability, and a tire tread, a bead filler, a tire belt and a heavy-duty tire which each partially include the composition. The heavy-duty tire rubber composition includes 100 parts by mass of a solid rubber (A), 0.1 to 50 parts by mass of a modified liquid diene rubber (B) having a functional group derived from a silane compound with a specific structure, and 20 to 200 parts by mass of a filler (C), the modified liquid diene rubber (B) satisfying the following (i) and (ii): (i) the weight average molecular weight (Mw) is not less than 1,000 and not more than 120,000, and (ii) the vinyl content is not less than 30 mol % and less than 70 mol %.

A rubber composition is based on at least one diene elastomer, a reinforcing filler, a crosslinking system and a hydrocarbon-based resin. The hydrocarbon-based resin has a number-average molecular weight (Mn) of between 700 and 1000 g/mol, an average molecular weight Mz of greater than 6000 g/mol and a polydispersity index (PI) of greater than 2.4.

A rubber composition is based on at least one diene elastomer, a reinforcing filler, a crosslinking system and a hydrocarbon-based resin. The hydrocarbon-based resin has a number-average molecular weight (Mn) of between 700 and 1000 g/mol, an average molecular weight Mz of greater than 6000 g/mol and a polydispersity index (PI) of greater than 2.4.

Recycled elements and/or renewable resources, such as recycled carbon black or recycled carbon black and recycled particulate rubber, are incorporated into a rubber composition. The rubber composition can be used to manufacture tires or various tire components including tire subtreads.

Recycled elements and/or renewable resources, such as recycled carbon black or recycled carbon black and recycled particulate rubber, are incorporated into a rubber composition. The rubber composition can be used to manufacture tires or various tire components including tire subtreads.

Provided is a rubber composition comprising: a rubber component containing diene-based rubber; a filler, and a compound represented by formula (I) below: ##STR00001##
(wherein: A is an aryl group and has at least two polar groups, which may be the same or different from each other; R.sup.1 and R.sup.2 are each independently at least one substituent selected from a group consisting of a hydrogen atom, an acyl group, an amide group, an alkyl group, a cycloalkyl group, and an aryl group; and further, the substituent may include one or more of O, S, and N atoms), so as to provide a rubber composition excellent in low heat generating property and wear resistance.

Provided is a rubber composition comprising: a rubber component containing diene-based rubber; a filler, and a compound represented by formula (I) below: ##STR00001##
(wherein: A is an aryl group and has at least two polar groups, which may be the same or different from each other; R.sup.1 and R.sup.2 are each independently at least one substituent selected from a group consisting of a hydrogen atom, an acyl group, an amide group, an alkyl group, a cycloalkyl group, and an aryl group; and further, the substituent may include one or more of O, S, and N atoms), so as to provide a rubber composition excellent in low heat generating property and wear resistance.

A functionalized graphene oxide nitrile rubber and A tooth-scar-free tooth block is provided. The functionalized graphene oxide nitrile rubber comprises the following components in parts by weight: 100-140 parts of nitrile rubber, 30-90 parts of a functionalized graphene oxide nitrile rubber masterbatch, 1.8-2.52 parts of a vulcanizing agent, 1.2-1.68 parts of a vulcanization accelerator, 5-7 parts of a vulcanization activator, 17-23.8 parts of a plasticizer, 2-2.8 parts of antioxidant, 59-86.6 parts of a filler, 0.1-0.14 parts of a curing agent, and 2-2.8 parts of dichlorophenol. The functionalized graphene oxide nitrile rubber above has excellent mechanical properties, a wide applicable temperature range and strong stability in use, and can be prepared into a tooth-scar-free tooth block.