The present invention relates to a silica-containing rubber mixture produced from at least one rubber, one sulphur-containing alkoxysilane, one crosslinking agent, one filler, and optionally further rubber auxiliary products and from 0.1 to 15 phr of a polysulphide additive of the formula (I)
A-S—(S).sub.x—S—Y—S—(S).sub.x—S-A  (I)
where x is 0, 1 or 2, Y is an aliphatic, cycloaliphatic or aromatic group that is optionally substituted or else comprises heteroatoms and A is an optionally substituted hydroxyethyl, carboxyaryl, hydroxyaryl, carboxyalkyl or thionamide moiety,
and comprises from 0.1 to 15 parts by weight, based on 100 parts by weight of rubber used, of 1,6-bis(N,N-dibenzylthiocarbamoyldithio)hexane (CAS No.: 151900-44-6).

A polymerization method including radically polymerizing a monomer in a polymerization medium comprising a chain transfer agent, and a free radical initiator prepared by oxidizing a reaction product of a ligand-reactive decomplexation agent and an alkyl-borane complex of the formula: ##STR00001##
wherein R.sub.1, R.sub.2, and R.sub.3 are independently selected from hydrogen, an alkyl group containing from 1 to 12 carbon atoms, a cycloalkyl group containing from 3-12 carbon atoms, and an aryl group containing from 6 to 12 carbon atoms, wherein the aryl group may be optionally substituted with an alkyl group having from 1 to 10 carbon atoms, and at least one of R.sub.1, R.sub.2, and R.sub.3 is an alkyl group, a cycloalkyl group or an aryl group, and L is a complexing agent selected from one or more amine groups, amidine groups, hydroxide groups, alkoxyl groups, alkyl ether groups, alkoxide groups and mixtures thereof.

A polymerization method including radically polymerizing a monomer in a polymerization medium comprising a chain transfer agent, and a free radical initiator prepared by oxidizing a reaction product of a ligand-reactive decomplexation agent and an alkyl-borane complex of the formula: ##STR00001##
wherein R.sub.1, R.sub.2, and R.sub.3 are independently selected from hydrogen, an alkyl group containing from 1 to 12 carbon atoms, a cycloalkyl group containing from 3-12 carbon atoms, and an aryl group containing from 6 to 12 carbon atoms, wherein the aryl group may be optionally substituted with an alkyl group having from 1 to 10 carbon atoms, and at least one of R.sub.1, R.sub.2, and R.sub.3 is an alkyl group, a cycloalkyl group or an aryl group, and L is a complexing agent selected from one or more amine groups, amidine groups, hydroxide groups, alkoxyl groups, alkyl ether groups, alkoxide groups and mixtures thereof.

A reinforced product, which can be used especially for reinforcing a finished rubber article, comprises one or more textile or metallic reinforcing thread(s), said thread(s) being covered with a sheath comprising a thermoplastic polymer composition, the sheathed thread(s) being themselves embedded in a rubber composition referred to as coating rubber, characterized in that this coating rubber is a composition based on at least one diene elastomer, silica as predominant reinforcing filler, and a sulfur-based vulcanization system, in which the ratio of the amounts, in phr (parts by weight per hundred parts by weight of elastomer), of sulfur and of reinforcing filler, is less than 0.08.

A reinforced product, which can be used especially for reinforcing a finished rubber article, comprises one or more textile or metallic reinforcing thread(s), said thread(s) being covered with a sheath comprising a thermoplastic polymer composition, the sheathed thread(s) being themselves embedded in a rubber composition referred to as coating rubber, characterized in that this coating rubber is a composition based on at least one diene elastomer, silica as predominant reinforcing filler, and a sulfur-based vulcanization system, in which the ratio of the amounts, in phr (parts by weight per hundred parts by weight of elastomer), of sulfur and of reinforcing filler, is less than 0.08.

The present invention relates to a thermally curable composition comprising: (a1) a solid rubber in an amount of 2.5% by mass or more, (a2) an olefinic double bond-containing polymer which is liquid or pasty at 22° C. in an amount of less than 5% by mass, (a3) a hydrocarbon resin in an amount of, in total with said component (a2), 5% by mass or more and 20% by mass or less, and (a4) a liquid polydiene in an amount of 15% by mass or more based on the total mass of the composition as a component (a); and at least one selected from the group consisting of the following (b1) to (b3): (b1) sulfur and one or more accelerator(s), (b2) peroxidic vulcanization system or disulfidic vulcanization system, and (b3) quinones, quinone dioximes or dinitrosobenzene, as a vulcanization system (b).

The present invention relates to a thermally curable composition comprising: (a1) a solid rubber in an amount of 2.5% by mass or more, (a2) an olefinic double bond-containing polymer which is liquid or pasty at 22° C. in an amount of less than 5% by mass, (a3) a hydrocarbon resin in an amount of, in total with said component (a2), 5% by mass or more and 20% by mass or less, and (a4) a liquid polydiene in an amount of 15% by mass or more based on the total mass of the composition as a component (a); and at least one selected from the group consisting of the following (b1) to (b3): (b1) sulfur and one or more accelerator(s), (b2) peroxidic vulcanization system or disulfidic vulcanization system, and (b3) quinones, quinone dioximes or dinitrosobenzene, as a vulcanization system (b).

A self-inflating tire assembly includes an air tube mounted within a tire sidewall groove. The air tube is in contacting engagement with opposite angled groove surfaces surrounding the air tube. A segment of the air tube is flattened from an expanded diameter to a flat diameter by bending and compression of the groove in a rolling tire footprint to force air evacuated from the flattened segment along a tube air passageway. The sidewall groove extends into an annular, axially extending, sidewall surface such as an axially oriented surface of a tire chafer protrusion located in non-contacting relationship with the rim. The opposite groove surfaces comprise a rubber composition, the rubber composition comprising: a diene based rubber; from 0.25 to 5 parts by weight, per 100 parts by weight of rubber (phr), of a self-lubrication agent capable of migrating from the rubber composition to the groove surface and disposing on the groove surface as a liquid; and from 1 to 15 parts by weight, per 100 parts by weight of rubber (phr), of a vulcanization modifier for use in the second rubber composition include α,ω-bis(N,N′-dihydrocarbylthiocarbamamoyldithio)alkanes, bismaleimides, and biscitraconimides.

A self-inflating tire assembly includes an air tube mounted within a tire sidewall groove. The air tube is in contacting engagement with opposite angled groove surfaces surrounding the air tube. A segment of the air tube is flattened from an expanded diameter to a flat diameter by bending and compression of the groove in a rolling tire footprint to force air evacuated from the flattened segment along a tube air passageway. The sidewall groove extends into an annular, axially extending, sidewall surface such as an axially oriented surface of a tire chafer protrusion located in non-contacting relationship with the rim. The opposite groove surfaces comprise a rubber composition, the rubber composition comprising: a diene based rubber; from 0.25 to 5 parts by weight, per 100 parts by weight of rubber (phr), of a self-lubrication agent capable of migrating from the rubber composition to the groove surface and disposing on the groove surface as a liquid; and from 1 to 15 parts by weight, per 100 parts by weight of rubber (phr), of a vulcanization modifier for use in the second rubber composition include α,ω-bis(N,N′-dihydrocarbylthiocarbamamoyldithio)alkanes, bismaleimides, and biscitraconimides.

A self-inflating tire assembly includes an air tube mounted within a tire sidewall groove. The air tube is in contacting engagement with opposite angled groove surfaces surrounding the air tube. A segment of the air tube is flattened from an expanded diameter to a flat diameter by bending and compression of the groove in a rolling tire footprint to force air evacuated from the flattened segment along a tube air passageway. The sidewall groove extends into an annular, axially extending, sidewall surface such as an axially oriented surface of a tire chafer protrusion located in non-contacting relationship with the rim. The opposite groove surfaces comprise a rubber composition, the rubber composition comprising: a diene based rubber; from 0.25 to 5 parts by weight, per 100 parts by weight of rubber (phr), of a self-lubrication agent capable of migrating from the rubber composition to the groove surface and disposing on the groove surface as a liquid; and from 1 to 15 parts by weight, per 100 parts by weight of rubber (phr), of a vulcanization modifier for use in the second rubber composition include α,ω-bis(N,N′-dihydrocarbylthiocarbamamoyldithio)alkanes, bismaleimides, and biscitraconimides.