It has been found that carboxylic acid functionalized high cis-1,4-polybutadiene rubber which is comprised of polybutadiene rubber chains having a cis-1,4-microstructure content of at least 90 percent has much better interaction with metal salts of α,β-ethylenically unsaturated carboxylic acids, such as zinc diacrylate or zinc dimethacrylate. This results in such rubber compositions being stiff while still exhibiting a lower level of hysteresis. These characteristics are beneficial when used in manufacturing tire apex compositions, in manufacturing golf ball cores, and in a wide variety of other applications. Such rubber compositions can be used as substitutes for thermoplastic elastomers in many applications.

To provide a method for producing a multicomponent copolymer with which a multicomponent copolymer having excellent rupture strength can be obtained, and a multicomponent copolymer, a rubber composition and a tire having excellent rupture strength. The method is a method for producing a multicomponent copolymer having a conjugated diene unit, a non-conjugated olefin unit and an aromatic vinyl unit, comprising adding a conjugated diene compound in divided portions into a reactor containing a catalyst and at least one selected from the group consisting of a non-conjugated olefin compound and an aromatic vinyl compound. The multicomponent copolymer is obtained with the production method. The rubber composition comprises the multicomponent copolymer as a rubber component. The tire uses the rubber composition.

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.

The present invention provides a run-flat tire excellent in run-flat durability. In the run-flat tire, a vulcanized rubber of a rubber composition containing a rubber component and a vulcanization accelerator that contains tetrabenzylthiuramdisulfide is used for at least one member selected from the group consisting of a side-reinforcing rubber layer and a bead filler. In the vulcanized rubber of the run-flat tire, a proportion of monosulfide bonds and disulfide bonds in all sulfide bonds is 65% or more.

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.

The present invention provides a run-flat tire excellent in high-temperature softening inhibition, and a rubber composition from which the tire can be produced. The rubber composition contains a rubber component, a filler, a vulcanizing agent, and a vulcanization accelerator that contains a sulfenamide-based vulcanization accelerator and 1.0 to 2.0 parts by mass of tetrabenzylthiuramdisulfide based on 100 parts by mass of the rubber component, in which a mass ratio (a/b) of a content (a) of the tetrabenzylthiuramdisulfide to a content (b) of the sulfenamide-based vulcanization accelerator is 0.60 to 1.25.

To provide a catalyst composition having high polymerization activity. To provide a polymer manufacturing method. To provide a polymer manufactured by the polymer manufacturing method. To provide a rubber composition including the polymer. To provide a tire using the rubber composition. A catalyst composition including a compound represented by Structural Formula I below, wherein the compound has an OH group at at least one position of the bipyridyl ring; M is a transition metal, a lanthanoid, scandium, or yttrium; R.sup.1 and R.sup.2 are a hydrocarbon group having one or more carbon atoms or a halogen atom; and R.sup.1 and R.sup.2 may be the same or different from each other. A polymer manufacturing method including a step of polymerizing one or more selected from the group consisting of a conjugated diene compound and a compound having an ethylenically unsaturated double bond in the presence of the catalyst composition. A polymer manufactured by the manufacturing method. A rubber composition including the polymer. A tire using the rubber composition. ##STR00001##

Disclosed is a method for manufacturing a pneumatic tire including a tread, sidewalls and a first bead and a second bead, which beads are spaced apart, the first bead and the second bead including: a drop shaped bead core , the drop shaped bead core having a cross sectional area including or consisting of a circular portion and a tapering portion, and an apex positioned adjacent and/or against the bead core, the method including: connecting the apex to the drop shaped bead core, thereby obtaining an assembly including the drop shaped bead core and the apex, pre-forming a tire including the assembly, and vulcanizing the pre-formed tire, thereby obtaining the pneumatic tire. Also disclosed is a pneumatic tire.

A coated wire includes a steel alloy coated with a coating comprising one or more amino alkoxy-modified silsesquioxane compounds selected from the group consisting of an amino alkoxy-modified silsesquioxane, an amino/mercaptan co-alkoxy-modified silsesquioxane, an amino/blocked mercaptan co-alkoxy-modified silsesquioxane, or a salt of one or more thereof. A rubber composition and a process for coating wire is also disclosed.

A pneumatic tire having a bead filler molded over a bead bundle to form an over-molded bead. The bead bundle may include at least one bead wire. The bead bundle may be over-molded with the bead filler, forming an over-molded bead. The over-molded bead may be formed into a variety of shapes and may be constructed from a variety of materials.