Abstract: An objective of the invention is to provide a conjugated diene-based rubber having a specific composition and a method of producing the same, an oil extended rubber using the same, as well as a rubber composition capable of being converted into a vulcanized rubber which has a low rolling resistance, an excellent wearing resistance and the like, and is useful, for example, as a tire or the like. A conjugated diene-based rubber in the invention has a glass transition point of −60 to 0° C., an olefinically unsaturated nitrile monomer unit randomly contains in its molecular chain, its repeating units consists of 9 to 30% by mass of an olefinically unsaturated nitrile monomer unit such as acrylonitrile, 10 to 50% by mass of an aromatic vinyl monomer unit such as styrene and 20 to 81% by mass of a conjugated diene monomer unit such as 1,3-butadiene, and its Mooney viscosity [ML1+4(100° C.)] is 20 to 200.

Abstract: An objective of the invention is to provide a conjugated diene-based rubber having a specific composition and an oil extended rubber using the same, as well as a rubber composition capable of being converted into a vulcanized rubber which has a low rolling resistance, an excellent wearing resistance and the like, and is useful for a tire or the like. A conjugated diene-based rubber in the invention has repeating units consisting of 1 to 30% by mass of an olefinically unsaturated nitrile monomer unit such as acrylonitrile, 10 to 50% by mass of an aromatic vinyl monomer unit such as styrene, 19.9 to 88.9% by mass of a conjugated diene monomer unit such as 1,3-butadiene and 0.1 to 10% by mass of a monomer unit having one polymerizable unsaturated group and at least one functional group selected from the group consisting of an amino group, a hydroxyl group, an epoxy group, a carboxyl group and an alkoxysilyl group, and has a specific glass transition point and a Mooney viscosity [ML1+4(100° C.

Abstract: An objective of the invention is to provide a rubber composition which has satisfactory processability and dimension stability, and the like, gives a vulcanized rubber exhibiting excellent wearing resistance and tensile strength, and the like, and thus is useful in a belt, a hose and a tire and the like, as well as a crosslinked rubber particle for obtaining such rubber composition. A rubber composition of the invention comprises [1] a crosslinked rubber particle comprising as repeating units (a) 30 to 94.89% by weight of a conjugated diene unit, (b) 5 to 69.89% by weight of an aromatic vinyl unit, (c) 0.01 to 10% by weight of a monomer unit having at least two polymerizable unsaturated group, (d) one polymerizable unsaturated group and an amino group, a hydroxyl group and an epoxy group and (e) 0.

Abstract: The present invention provides a rubber composition which has satisfactory processability and dimension stability, exhibits excellent tensile strength and wearing resistance, and the like when vulcanized and is useful as a material for an industrial product such as a rubber roll, a grinding roll, a belt, a hose and a rubber-coated fabric, a shoe part for example of a transparent shoe, a tire of a large-sized or small sized car such as a tread and a side wall and a sanitary material such as a contraceptive rubber or the like. A rubber composition of the invention comprises (1) a crosslinked rubber particle containing as repeating units (a) 39.89 to 79.89% by weight of a conjugated diene unit such as 1,3-butadiene or the like, (b) 20 to 60% by weight of an aromatic vinyl unit such as styrene, (c) 0.01 to 10% by weight of a monomer unit having at least two polymerizable unsaturated group such as divinylbenzene, and the like, and (d) 0.

Abstract: A multi-component copolymer rubber consisting essentially of (A) 20 to 69.5% by weight of a cyano-substituted alkyl (meth)acrylate, (B) 30 to 79.5% by weight of an alkyl acrylate, (C) 0.5 to 10% by weight of a crosslinkable monomer and (D) 0 to 10% by weight of other ethylenically unsaturated monomer copolymerizable with (A), (B) and (C), excels in heat resistance, ozone resistance, sour gasoline resistance and sour gasohol resistance. There properties of said multi-component copolymer rubber can further be improved by incorporating into the copolymer rubber a crosslinking agent, a metal salt, a vinylidene fluoride polymer, a vinyl chloride resin or other multi-component copolymer rubber.

Abstract: A multi-component copolymer rubber consisting essentially of (A) 20 to 69.5% by weight of a cyano-substituted alkyl (meth)acrylate, (B) 30 to 79.5% by weight of an alkyl acrylate, (C) 0.5 to 10% by weight of a crosslinkable monomer and (D) 0 to 10% by weight of other ethylenically unsaturated monomer copolymerizable with (A), (B) and (C), excels in heat resistance, ozone resistance, sour gasoline resistance and sour gasohol resistance. These properties of said multi-component copolymer rubber can further be improved by incorporating into the copolymer rubber a crosslinking agent, a metal salt, a vinylidene fluoride polymer, a vinyl chloride resin or other multi-component copolymer rubber.