A pneumatic tire having a tread, a sidewall, a bead portion having a bead core, a bead reinforcing layer reinforcing the bead portion, and a carcass ply moored on a bead core of the bead portion, wherein the bead reinforcing layer and adjacent members adjacent to the bead reinforcing layer are each composed of a rubber composition containing an amine type antioxidant, 0.3 to 8 parts by mass of the amine type antioxidant is contained in the bead reinforcing layer based on 100 parts by mass of the rubber component, and the adjacent member adjacent to the bead reinforcing layer and the bead reinforcing layer satisfy the following formula:
2≤B/A≤8
A: Content (wt %) of amine type antioxidant in bead reinforcing layer.
B: Content (wt %) of amine type antioxidant in the adjacent member.

An object of the present disclosure is to provide a copolymer containing at least an acyclic non-conjugated olefin unit and a conjugated diene unit and capable of improving an elastic modulus of a rubber composition. Specifically, the present disclosure provides a copolymer containing at least an acyclic non-conjugated olefin unit and a conjugated diene unit, wherein the difference (T.sub.em−T.sub.im) between an extrapolated melting end temperature (T.sub.em) as measured in accordance with JIS K7121 and an extrapolated melting initiation temperature (T.sub.im) as measured in accordance with JIS K7121 is not higher than 60° C.

In a pneumatic tire, at least one carcass layer mounted between a pair of bead portions is formed from a carcass cord formed of an organic fiber cord having filament bundles of organic fibers intertwined together, a fineness based on corrected mass of the carcass cord is from 4000 dtex to 8000 dtex, an intermediate elongation of the carcass cord at a sidewall portion under 1.0 cN/dtex load is from 3.3% to 4.2%, and a ratio G/R of an interlayer rubber gauge G between a body portion and a folded back portion to a cord diameter R of the carcass cord, at a contact region where the body portion and the folded back portion are in contact in the carcass layer, is from 0.50 to 0.60.

A rubber composition based at least on a functional elastomer and a reinforcing filler which comprises a carbon black is provided. The functional elastomer is a diene elastomer which comprises diene units in the cis-1,4 configuration and pendant groups of formula (I). The Y.sub.1, Y.sub.2, Y.sub.3 and Y.sub.4 symbols, which are identical or different, represent an atom or a group of atoms, and at least one of the symbols denotes an attachment to a diene unit of the elastomer. The diene units in the cis-1,4 configuration represent at least 90 mol % of the diene units of the functional elastomer, and the carbon black represents more than 50% by weight of the reinforcing filler. ##STR00001##

A process for the manufacture of a reinforced product comprising a matrix based on a composition and at least one reinforcing element, the reinforcing elements being embedded in the matrix, comprises: mixing of the composition based on: a compound A1 with a melting point T1, and a compound A2 with a melting point T2, at a temperature Tm such that: T1≤Tm<T2, so as to dissolve A2 in A1 and to obtain the composition in the liquid state; submerging of the reinforcing element(s) (36) in the composition; and crosslinking by heating of the composition at a temperature Tn such that: T1≤Tm<Tn.

The present invention provides a molded bale of a rubber composition that is difficult to cold flow, and is difficult to be thermally deteriorated during production, and in which rigidity at 50° C. of a rubber composition for crosslinking obtained therefrom is difficult to be low, and change of tensile strength of the rubber composition for crosslinking after thermal history is small. The rubber composition contains: a rubber-like polymer (A) having an iodine value of 10 to 250, 3% by mass or more of an ethylene structure, and less than 10% by mass of a vinyl aromatic monomer block; aluminum (B); and nickel and/or cobalt (C), in which a content of the aluminum (B) is 2 ppm or more and 200 ppm or less, and a content of the nickel and/or cobalt (C) is 3 ppm or more and 100 ppm or less.

A modified conjugated diene-based polymer containing: having a weight average molecular weight of 20×10.sup.4 or more and 300×10.sup.4 or less, having a star-branched structure with a conjugated diene-based polymer chain bonded to a modifier residue, wherein the modifier residue has at least 4 silicon atoms, and alkoxy groups and/or hydroxyl groups and the conjugated diene-based polymer chain is bonded to the silicon atom, wherein the number of alkoxy groups and/or hydroxyl groups in the modifier residue is larger than the number of the silicon atoms on average.

[Problem to be Solved] Provided is a method for producing a non-petrochemical-derived conjugated diene polymer using an alcohol derived from a non-petrochemical raw material.

[Means to Solve the Problem] In the present invention, the method is characterized in that a non-petrochemical-derived conjugated diene polymer is produced using an alcohol derived from a non-petrochemical raw material having an iron content of 0.0001 mg/L to 2 mg/L.

A rubber-steel cord composite in which a rubber composition and a steel cord are vulcanized and adhere to each other, wherein the rubber composition contains 1 to 10 parts by mass of a vulcanizing agent, 0.1 to 5 parts by mass of N,N-dibenzylbenzothiazole-2-sulfenamide, and 0.1 to 5 parts by mass of a bismaleimide compound, with respect to 100 parts by mass of diene rubber containing natural rubber.

A rubber-steel cord composite according to an embodiment is formed by vulcanizing and bonding a rubber composition containing 1 to 10 parts by mass of sulfur, 0.1 to 5 parts by mass of N,N-dibenzylbenzothiazole-2-sulfenamide, and 0.1 to 5 parts by mass of either one or both of hexamethylene bis-thiosulfate disodium salt dihydrate and 1,6-bis(N,N-dibenzylthiocarbamoyldithio)hexane, with respect to 100 parts by mass of diene rubber containing natural rubber, and a steel cord. A pneumatic tire according to an embodiment includes the rubber-steel cord composite.