The present disclosure relates to a rubber composition for tire tread and a tire manufactured by using the same, and the rubber composition for tire tread improves rolling resistance and abrasion resistant performance and can improve handling and braking performances on a wet road surface and an ice and snow road surface at the same time by comprising 100 parts by weight of raw rubber and 70 to 120 parts by weight of a reinforcing filler, wherein the raw rubber includes 0 to 50 parts by weight of natural rubber, 20 to 100 parts by weight of a melt grafting-functionalized styrene butadiene rubber, and 0 to 30 parts by weight of butadiene rubber.

A functionalized elastomer comprising the reaction product of a living elastomeric polymer and a polymerization terminator of formula I

[R.sup.1].sub.n—B—[X—R.sup.2].sub.m  I

where B is boron; X is oxygen or nitrogen; R.sup.1 is independently vinyl, oxiranyl, phenyl, 1-alkenyl of 2 to 8 carbon atoms, alkyl of 1 to 8 carbon atoms including at least one halogen atom, 1-alkenyl of 2 to 8 carbon atoms including at least one halogen or one hydrogen; R.sup.2 is independently C1 to C8 alkyl, C8 to C14 aryl; or when m>1 R.sup.2 may be taken together to form a substituted or unsubstituted cyclic structure comprising 2 to 16 carbon atoms where the cyclic structure may be heterocyclic or non-heterocyclic; n is 1 or 2, m is 1 or 2, and n+m=3.

Disclosed herein are a terminal-functionalized polymer, rubber compositions containing the polymer, and related processes for preparing the polymer. The functionalizing compound used to prepare the terminal-functionalized polymer has a specified formula which includes a silicon atom and a moiety containing at least two carbon-carbon double bonds in a conjugated configuration.

The present invention aims to provide rubber compositions and tires which provide improved overall performance in terms of wet grip performance and dry grip performance. The present invention relates to a rubber composition having a hardness that reversibly changes with water and satisfying the following relationship (1):

Hardness when dry−Hardness when water-wet≥10   (1)

wherein each hardness represents the JIS-A hardness at 25° C. of the rubber composition.

Reinforcing fibers containing hydrophilic fibers and an adhesive component, wherein at least a part of the surfaces of the hydrophilic fibers have the adhesive component, the adhesive component contains a modified conjugated diene rubber having a hydrogen-bonding functional group in a part of the conjugated diene rubber, and the number of the hydrogen-bonding functional groups in the modified conjugated diene rubber is 2 to 150 per molecule on average; a method for producing the reinforcing fibers; and a molded article using the reinforcing fibers.

A pneumatic tire includes 100 parts by mass of a rubber component including from 25-30 parts by mass of a diene rubber having a glass transition temperature of from −20° C. to −40° C., having a tertiary amine having an epoxy group as a modifying group, and a vinyl content from 35-45 mass %, 20-35 parts by mass of a diene rubber obtained by reacting a polyorganosiloxane to an active terminal of a diene-based polymer chain having the active terminal formed by making a polymer block A continuous with a polymer block B, the polymer block A including 80-95 mass % of isoprene and 5-20 mass % of an aromatic vinyl, having an active terminal, and having a weight average molecular weight from 500-15,000, the polymer block B including 1,3-butadiene and an aromatic vinyl and an active terminal, the vinyl content lower by from 5-25 mass % than that of the first conjugated diene polymer.

Disclosed herein are a terminal-functionalized polymer, rubber compositions containing the polymer, and related processes for preparing the polymer. The functionalizing compound used to prepare the terminal-functionalized polymer has a specified formula which includes a silicon atom and a moiety containing at least two carbon-carbon double bonds in a conjugated configuration.

Disclosed herein are a terminal-functionalized polymer, rubber compositions containing the polymer, and related processes for preparing the polymer. The functionalizing compound used to prepare the terminal-functionalized polymer has a specified formula which includes a silicon atom and a moiety containing at least two carbon-carbon double bonds in a conjugated configuration.

A latex of an acid-modified conjugated diene polymer including the acid-modified conjugated diene polymer obtained by modifying a conjugated diene polymer with an acid group-containing compound, in which a content of a structural unit derived from the acid group-containing compound is 0.2 to 0.7 parts by weight with respect to 100 parts by weight of the acid-modified conjugated diene polymer; a content of a water-soluble polymer in the latex is 2 parts by weight or less with respect to 100 parts by weight of the acid-modified conjugated diene polymer; when a solids content of the latex is adjusted to 60 wt %, a viscosity at 25 C. is 800 mPa.Math.s or less; and when the solids content of the latex is adjusted to 50 wt %, the viscosity at 25 C. is 300 mPa.Math.s or less.

A pneumatic tire includes 100 parts by mass of a rubber component including from 25-30 parts by mass of a diene rubber having a glass transition temperature of from 20 C. to 40 C., having a tertiary amine having an epoxy group as a modifying group, and a vinyl content from 35-45 mass %, 20-35 parts by mass of a diene rubber obtained by reacting a polyorganosiloxane to an active terminal of a diene-based polymer chain having the active terminal formed by making a polymer block A continuous with a polymer block B, the polymer block A including 80-95 mass % of isoprene and 5-20 mass % of an aromatic vinyl, having an active terminal, and having a weight average molecular weight from 500-15,000, the polymer block B including 1,3-butadiene and an aromatic vinyl and an active terminal, the vinyl content lower by from 5-25 mass % than that of the first conjugated diene polymer.