The invention provides a heavy-duty tire rubber composition excellent in wet grip performance and steering stability, and a tire tread, a bead filler, a tire belt and a heavy-duty tire which each partially include the composition. The heavy-duty tire rubber composition includes 100 parts by mass of a solid rubber (A), 0.1 to 50 parts by mass of a modified liquid diene rubber (B) having a functional group derived from a silane compound with a specific structure, and 20 to 200 parts by mass of a filler (C), the modified liquid diene rubber (B) satisfying the following (i) and (ii): (i) the weight average molecular weight (Mw) is not less than 1,000 and not more than 120,000, and (ii) the vinyl content is not less than 30 mol % and less than 70 mol %.

A resin composition, comprising a thermoplastic elastomer and an epoxy resin as resins, and zinc cyanurate.

In a pneumatic tire in which a reinforcing layer including a cord is embedded, a coating rubber covering the cord included in the reinforcing layer uses a rubber composition in which 30 parts by mass to 60 parts by mass of carbon black having a nitrogen adsorption specific surface area N.sub.2SA of 100 m.sup.2/g or more and 0 parts by mass or more and 10 parts by mass or less of aroma oil is optionally blended, per 100 parts by mass of a rubber component containing 70 mass % to 100 mass % of a natural rubber and in which a strength at break TB (unit: MPa) at 100° C. and a stress M100 (unit: MPa) at 100% elongation at 100° C. satisfy a relationship TB.sup.2/M100≥50.0.

The invention relates to a sulfur-crosslinkable rubber mixture and to a pneumatic vehicle tire comprising at least one rubber component made of the sulfur-vulcanized rubber mixture.

The rubber mixture contains 10-60 phr (parts by weight, based on 100 parts by weight of the total rubbers in the mixture) of at least one functionalized polybutadiene A,
wherein the functionalized polybutadiene A is functionalized at one chain end with an organosilyl group containing amino groups and/or ammonium groups,
and wherein the functionalized polybutadiene A is functionalized at the other chain end with an amino group, up to 90 phr of at least one further diene rubber and 30-350 phr of at least one filler.

The conjugated diene-based polymer has a Mooney viscosity measured at 100° C. of 40 or more and 170 or less, has Mooney stress relaxation measured at 100° C. of 0.35 or less, and has a branch number (Bn) measured by viscosity detector-equipped GPC-light scattering measurement of 8 or more.

The invention relates to a plasticizer system for use in a tread rubber composition. The plasticizer system is partially derived from or devoid of petroleum-based oils and resins. The pneumatic tire has a tread of a rubber composition comprising, based on 100 parts by weight of elastomer (phr): from about 10 to about 60 phr of a solution polymerized styrene-butadiene rubber (SSBR) extended with an oil not derived from petroleum; and a plasticizer system comprised of (1) from about 4 to about 8 phr of a plasticizing oil not derived from petroleum, and (2) from about 10 to about 20 phr of a hydrocarbon plasticizing resin selected from styrene/α-methyl styrene resin and polyterpene plasticizing resin.

The present invention is directed to a pneumatic tire having a tread comprising a vulcanizable rubber composition comprising, based on 100 parts by weight of elastomer (phr), up to 100 phr of a solution polymerized styrene-butadiene rubber; from 5 to 50 phr of a fatty acid monoester of formula 1 ##STR00001##
where R.sup.1 is selected from C1 to C8 linear or branched alkyl, C1 to C8 linear or branched alkenyl, and C2 to C6 linear or branched alkyl substituted with from one to five hydroxyl groups; R.sup.2 is C11 to C21 alkyl or C11 to C21 alkenyl; from 5 to 50 phr of a hydrocarbon resin having a Tg ranging from −40° C. to 20° C.; less than 10 phr of a petroleum-derived oil; and from 50 to 130 phr of silica. optionally, from about 1 to 50 phr carbon black.

A pneumatic tire includes: a bead core; a bead filler; a carcass ply; a side wall rubber that is arranged on the tire-outer-surface-side of the carcass ply and constitutes a tire outer surface; a chafer layer that is turned from the tire-inner-surface-side to the tire-outer-surface-side around the bead core and the bead filler and rolled up on an outer surface of the carcass ply; a pair of a tape rubber and a rear pad rubber that are located between the side wall rubber and the carcass ply and arranged so as to hold a rolled-up end of the chafer layer from both sides in a tire width direction; and a tread rubber, in which modulus values of the pair of the tape rubber and the rear pad rubber are higher than a modulus value of the side wall rubber, and the tread rubber contains silica.

A rubber composition exhibiting an improved processability/stiffness compromise is based on at least a diene elastomer, a reinforcing filler, a crosslinking system, between 1 and 30 parts by weight per hundred parts by weight of elastomer, phr, of an epoxy resin and between 1 and 15 phr of a specific amine-comprising hardener comprising in particular at least two primary amine functional groups located on at least one six-membered aromatic ring and at least two Ri radicals, which are identical or different, selected from the group consisting of linear or branched C.sub.1-C.sub.6 alkyl radicals, halogens, and ethers, tertiary amines, thioethers, ketones, esters and amides, substituted by linear or branched C.sub.1-C.sub.6 alkyl radicals, the said ring not comprising a hydrogen atom located in the ortho position with respect to the primary amine functional groups.

The present invention is directed to a benzoxazine-functionalized diene-based elastomer comprising polymer chains including repeat units which include conjugated diolefin monomers, such as 1,3-butadiene and isoprene. Additionally, said elastomer comprises at least one benzoxazine connected to a polymer chain via a spacer, wherein the spacer has a length ranging from 3 to 8 atoms. A further aspect of the present invention is directed to a rubber composition comprising such an elastomer, an article of manufacture comprising this rubber composition, and a method of making said benzoxazine-functionalized diene-based elastomer.