The present disclosure relates to a modified conjugated diene-based polymer, a method for preparing the same and a rubber composition comprising the same, and the modified conjugated diene-based polymer has narrow molecular weight distribution, and includes S atoms in the specific content in the polymer, a derived unit from an N-containing aromatic hydrocarbon compound, a derived unit from an S-containing aromatic hydrocarbon compound or an S-containing heterocyclic compound.

A tire having excellent wet grip performance and low rolling resistance is provided. This tire is a tire obtained by using a rubber composition that includes a rubber component containing a rubber having an isoprene structure and an aminoalkoxysilane-modified styrene-butadiene rubber having an amount of bonded styrene of 15% or less; a filler containing a silica having a nitrogen adsorption specific surface area (BET method) of 130 m.sup.2/g or more and less than 330 m.sup.2/g, the amount of the filler being 40 to 125 parts by mass with respect to 100 parts by mass of the rubber component; and a hydrogenated resin having a softening point of higher than 110° C. and having a weight average molecular weight as converted to polystyrene of 200 to 1200 g/mol, the amount of the hydrogenated resin being 5 to 50 parts by mass per 100 parts by mass of the rubber component.

The present invention relates to a modified conjugated diene-based polymer having excellent wet skid resistance and abrasion resistance in a balanced way, and a rubber composition comprising the same, and the modified conjugated diene-based polymer is characterized in including: a repeating unit derived from a conjugated diene-based monomer; and a functional group derived from a modifier, wherein, if measured by differential scanning calorimetry (DSC) through controlling the microstructure of the polymer, a difference between a glass transition onset temperature (T.sub.g-on) and a glass transition offset temperature (T.sub.g-off), which arise glass transition, is 10° C. to 30° C., thereby having excellent wet skid resistance and running resistance in a balanced way and improved effects of abrasion resistance, simultaneously.

This disclosure provides a rubber composition that can realize excellent low heat generating properties without deteriorating other performance. The rubber composition contains a rubber component and a filler, where the rubber component contains a conjugated diene-based polymer modified with a modifier containing a compound represented by the formula (1).

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The present disclosure provides a tire which makes it possible to reduce the increase in hardness and the decrease in wet grip performance from before to after heat aging. The present disclosure relates to a tire including a tread, the tread including an elastomer composition containing a styrene elastomer and urethane particles, the tread satisfying the following relationship (1): (M100a−M100f)/M100f×100≤38 wherein M100f represents the stress at 100% elongation (23° C.) before heat aging, and M100a represents the stress at 100% elongation (23° C.) after heat aging.

A modified conjugated diene-based polymer and a rubber composition including the same are disclosed herein. In some embodiments, the modified conjugated diene-based polymer includes a modified monomer-derived functional group represented by Formula 1, and an aminoalkoxysilane-based modifier-derived functional group at least one end thereof, wherein the polymer having a unimodal molecular weight distribution, and a polydispersity index (PDI) of 1.0 or more to less than 1.7. The polymer has a narrow and unimodal molecular weight distribution, and has excellent tensile properties and viscoelastic properties while having excellent processability.

A modified conjugated diene-based polymer and a rubber composition including the same are disclosed herein. In some embodiments, the modified conjugated diene-based polymer includes a modified monomer-derived functional group represented by Formula 1, and an aminoalkoxysilane-based modifier-derived functional group at least one end thereof, wherein the polymer having a unimodal molecular weight distribution, and a polydispersity index (PDI) of 1.0 or more to less than 1.7. The polymer has a narrow and unimodal molecular weight distribution, and has excellent tensile properties and viscoelastic properties while having excellent processability.

A modified conjugated diene-based polymer represented by Formula 1, wherein a terminal of a polymer chain is modified, and a method for preparing same are provided. By including a modifier derived unit having a specific structure, a beta value affecting cold flow may be reduced through controlling the degree of branch, and accordingly, the cold flow of a polymer may be efficiently controlled and a mooney viscosity increasing ratio may be improved.

The present invention relates to a method for the preparation of a synthetic rubber blend, wherein the blend comprises a high molecular weight polydiene (A) and a low molecular weight polydiene (B). The present invention further relates to a synthetic rubber blend obtainable according to the method described herein; as well as to rubber compositions comprising the blend; and articles, such as tires.

The invention relates to a copolymer of ethylene and of a 1,3-diene of formula CH.sub.2═CR—CH═CH.sub.2, which copolymer bears a silanol or alkoxysilane function, the symbol R representing a hydrocarbon chain having from 3 to 20 carbon atoms. Such a copolymer improves the compromise between the content of ethylene in the polymer, its crystallinity and the stiffness of a rubber composition containing it.