Abstract: Provided is a rubber composition that can achieve excellent breaking resistance while having high operability. A rubber composition comprises: a rubber component containing a multicomponent copolymer that contains a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit; and at least one selected from an ethylene-? olefin copolymer and an ethylene-aromatic vinyl copolymer each having a number-average molecular weight of 500 to 30,000.

Abstract: Provided is a rubber composition that can achieve excellent breaking resistance while having high operability. A rubber composition comprises: a rubber component containing a multicomponent copolymer that contains a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit; and an ?-olefin having a number-average molecular weight (Mn) of 50 to 1,000.

Abstract: Provided is a rubber composition being excellent in cut resistance while maintaining good elongation fatigue resistance. The rubber composition of the present disclosure contains a rubber component containing 70% by mass or more of natural rubber, a filler containing at least silica, and a cyclic polyol compound having a hydrocarbyl group of 0.1 parts by mass to 2 parts by mass with respect to 100 parts by mass of the natural rubber in the rubber component.

Abstract: The present invention provides: a rubber composition having a good low heat generation property and is excellent in high elastic modulus and fracture resistance, and a tire using the rubber composition. The rubber composition contains a rubber component that contains a diene rubber, and the diene rubber contains a polymer (A) of a copolymer that has, in one molecule, a block moiety containing a urethane backbone segment and a block moiety containing a diene backbone segment.

Abstract: Provided is rubber composition that can improve wear resistance and cutting resistance while having good fuel efficiency when applied to a tire. The rubber composition contains a rubber component containing natural rubber and/or synthetic isoprene rubber, and syndiotactic 1,2-polybutadiene, where the syndiotactic 1,2-polybutadiene has a crystal content of 7 J/g to 40 J/g and a number-average molecular weight of 6.5×104 or more.

Abstract: An object of the present disclosure is to provide a polymer exhibiting reduced heat generation in a low strain region. To achieve the object, the present disclosure provides a multi-component copolymer, comprising a non-conjugated olefin unit, a conjugated diene unit, and an aromatic vinyl unit, characterized in that: a ratio [(C100-120/C0-1000)×100] of crystallinity (C100-120) derived from the non-conjugated olefin unit at 100-120° C. with respect to crystallinity (C0-100) derived from the non-conjugated olefin unit at 0-100° C., as measured by a differential scanning calorimeter (DSC), is 23% or less.

Abstract: Provided is a rubber composition that can achieve excellent breaking resistance while having high operability. A rubber composition comprises: a rubber component containing a multicomponent copolymer that contains a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit; and at least one selected from an ethylene-? olefin copolymer and an ethylene-aromatic vinyl copolymer each having a number-average molecular weight of 500 to 30,000.

Abstract: Provided is a rubber composition that can achieve excellent breaking resistance while having high operability. A rubber composition comprises: a rubber component containing a multicomponent copolymer that contains a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit; and an ?-olefin having a number-average molecular weight (Mn) of 50 to 1,000.

Abstract: The rubber composition of the present invention contains: a rubber component (A) containing a butadiene-based rubber and 30% by mass or more of a natural rubber; a filler (B); 30 to 55 parts by mass of a softening agent (C) relative to 100 parts by mass of the rubber component (A); and 1 to 6 parts by mass of a linear polyhydric alcohol (D) relative to 100 parts by mass of the rubber component (A), wherein the softening agent (C) contains a softening agent (C1) which has a high affinity to the natural rubber in an amount of 0 parts by mass or more and less than 15 parts by mass relative to 100 parts by mass of the rubber component (A) and contains a softening agent (C2) which has a high affinity to the butadiene-based rubber in an amount of 10 parts by mass or more relative to 100 parts by mass of the rubber component (A). From the rubber composition, a crosslinked rubber composition having a good balance between low heat generation property and crack resistance can be obtained.

Abstract: An object of the present invention is to provide a rubber composition from which a crosslinked rubber composition having excellent crack resistance and high breaking elongation and breaking stress can be obtained. Further, another object thereof is to provide a rubber product and a tire using the rubber composition. A rubber composition of the present invention comprises a rubber component (A) comprising 30% by mass or more of a natural rubber and a synthetic isoprene rubber in total, at least one (B) selected from the group consisting of a reclaimed rubber and a powdered rubber, and a polyhydric alcohol (C) having 3 or more hydroxyl groups per molecule.

Abstract: An object of the present invention is to provide a rubber composition from which a vulcanized rubber having excellent wear resistance and a high breaking elongation and a high breaking stress can be obtained. Further, another object of the present invention is to provide a vulcanized rubber obtained by vulcanizing the rubber composition, and a rubber product and a tire comprising the rubber composition or the vulcanized rubber. The rubber composition of the present invention includes a rubber component (A), a foaming agent (B), and a polyhydric alcohol (C) having 3 or more hydroxyl groups per molecule, wherein the rubber component (A) comprises 30% by mass or more of natural rubber based on the entire rubber component, and a content of the polyhydric alcohol (C) is 1 to 6 parts by mass per 100 parts by mass of the rubber component (A).

Abstract: Disclosed is a rubber composition which comprise: a rubber component containing 30% by mass or more of a natural rubber; and 0.1 parts by mass or more and less than 5.0 parts by mass of a polyol per 100 parts by mass of the rubber component, wherein the rubber composition has a 300% modulus (M300) of less than 7 MPa.

Abstract: Disclosed is a rubber composition which comprises: a rubber component containing 30% by mass or more of a natural rubber and/or a synthetic polyisoprene; and a total of less than 10 parts by mass of a linear polyol and a cyclic polyol per 100 parts by mass of the rubber component.

Abstract: An object of the present invention is to provide a rubber composition from which a tire having high elasticity and excellent elongation fatigue resistance can be obtained. A rubber composition of the present invention comprises a rubber component (A), a linear polyhydric alcohol (B), and a silica (C), in which the total content of a natural rubber and a synthetic polyisoprene rubber in the rubber component (A) is 30% by mass or more, and the content of the silica (C) is more than 0 parts by mass and less than 10 parts by mass per 100 parts by mass of the rubber component (A).

Abstract: The present invention is concerned with a rubber composition containing a cyclic polyol compound having a hydrocarbyl group and a hydroxy group and having two or more and ten or less cyclic structures; carbon black; and a rubber component. A crosslinked rubber obtained from such a rubber composition is excellent in crack resistance and elongation at break at a high temperature.