A resin composition is provided, wherein polymer particles are dispersed in a matrix of an ethylene-vinyl alcohol copolymer and the polymer particles have a sea-island structure, and one of a sea component and an island component has a glass transition temperature of 30° C. or more and the other has a glass transition temperature of −10° C. or less. The resin composition has high gas barrier properties and is also excellent in impact resistance, particularly impact resistance at low temperatures.

The present invention provides a pneumatic tire achieving a balanced improvement in fuel economy, abrasion resistance, and wet grip performance. The present invention relates to a pneumatic tire, including a tread containing a tread rubber composition, the tread rubber composition containing a rubber component including 30% by mass or more of a styrene-butadiene rubber, the tread rubber composition containing, per 100 parts by mass of the rubber component: 80 to 150 parts by mass of silica; 0.1 to 3.0 parts by mass of a tetrazine compound of formula (1); and 50 parts by mass or less of a hydrocarbon resin having a SP value of 7.5 to 10.5, the styrene-butadiene rubber having a styrene content of 23% by mass or higher.

The present invention provides a pneumatic tire achieving a balanced improvement in fuel economy, abrasion resistance, and wet grip performance. The present invention relates to a pneumatic tire, including a tread containing a tread rubber composition, the tread rubber composition containing a rubber component including 30% by mass or more of a styrene-butadiene rubber, the tread rubber composition containing, per 100 parts by mass of the rubber component: 80 to 150 parts by mass of silica; 0.1 to 3.0 parts by mass of a tetrazine compound of formula (1); and 50 parts by mass or less of a hydrocarbon resin having a SP value of 7.5 to 10.5, the styrene-butadiene rubber having a styrene content of 23% by mass or higher.

The present invention relates to a method for preparing a conjugated diene-based polymer, characterized in using a dimer acid saponified material as an emulsifier in a polymerization initiation step and injecting a monomer and the emulsifier in three or more installments after initiating polymerization, and the conjugated diene-based polymer prepared by the preparation method of the present invention has excellent physical properties such as impact strength and reflection haze.

The present invention relates to a method for preparing a conjugated diene-based polymer, characterized in using a dimer acid saponified material as an emulsifier in a polymerization initiation step and injecting a monomer and the emulsifier in three or more installments after initiating polymerization, and the conjugated diene-based polymer prepared by the preparation method of the present invention has excellent physical properties such as impact strength and reflection haze.

This invention discloses a tire tread comprising: (a) a first tread cap layer comprising a first rubber composition; and (b) a second tread cap layer arranged radially inside of the first tread cap layer comprising a second rubber composition; wherein at 0° C. the rebound resilience of the first rubber composition is within a range of 10% to 25%, the rebound resilience of the second rubber composition is within a range of 15% to 35% and is at least 5% lower than that of the second rubber composition; and wherein at 100° C. the rebound resilience of the first rubber composition is within a range of 45% to 65%, the rebound resilience of the second rubber composition is within a range of 60% to 75% and is at least 3% higher than that of the first rubber composition.

This invention discloses a tire tread comprising: (a) a first tread cap layer comprising a first rubber composition; and (b) a second tread cap layer arranged radially inside of the first tread cap layer comprising a second rubber composition; wherein at 0° C. the rebound resilience of the first rubber composition is within a range of 10% to 25%, the rebound resilience of the second rubber composition is within a range of 15% to 35% and is at least 5% lower than that of the second rubber composition; and wherein at 100° C. the rebound resilience of the first rubber composition is within a range of 45% to 65%, the rebound resilience of the second rubber composition is within a range of 60% to 75% and is at least 3% higher than that of the first rubber composition.

Disclosed herein are processes for preparing a resin-extended rubber by mixing at least one thermoplastic resin with a resin-rubber-solvent cement comprising at least one conjugated diene monomer-containing rubber and the resin-extended rubber resulting from such processes. Also disclosed is a resin-extended rubber-solvent-cement comprising at least one conjugated diene monomer-containing rubber, at least one non-polar solvent, and at least one thermoplastic resin as well as a rubber composition comprising a resin-extended rubber.

Disclosed herein are processes for preparing a resin-extended rubber by mixing at least one thermoplastic resin with a resin-rubber-solvent cement comprising at least one conjugated diene monomer-containing rubber and the resin-extended rubber resulting from such processes. Also disclosed is a resin-extended rubber-solvent-cement comprising at least one conjugated diene monomer-containing rubber, at least one non-polar solvent, and at least one thermoplastic resin as well as a rubber composition comprising a resin-extended rubber.

The purpose is to provide rubber compositions and pneumatic tires which have reduced changes in tan δ peak temperature over time. The present invention relates to rubber compositions containing at least one copolymer obtained by copolymerizing an aromatic vinyl compound and a conjugated diene compound, the rubber compositions having a heat aging resistance index defined by equation (1) of 0.45 or less.