Abstract: Rubber composition usable for the manufacture of metallic rubberised fabrics and capable of adhering to a metallic reinforcing member, comprising a diene elastomer, a reinforcing filler, a cross-linking system and an adhesion promoter, said adhesion promoter comprising at least one lanthanide compound, preferably an organolanthanide. Metal/rubber composite comprising such a composition and its use for the manufacture or the reinforcement of ground contact systems of motor vehicles such as tires. Ground contact systems and semi-finished rubber products, in particular tires, comprising such a composite. The lanthanide compound imparts to the composition and to the composite improved adhesive properties after thermal ageing, in particular in humid conditions. It may be used alone or in combination with a cobalt compound, in particular in carcass or crown reinforcements of passenger-vehicle or heavy-vehicle tires.

Abstract: The present invention relates to a vulcanizable rubber composition which can be used for the manufacture of tires, a process for the preparation of this composition and a tire, the tread of which comprises such a composition, the latter having improved hysteresis and physical properties in the vulcanized state, while retaining satisfactory processing properties. A rubber composition according to the invention comprises a reinforcing white filler, and is such that it comprises at least one diene block polymer which is intended to interact with said reinforcing white filler and which comprises on at least one of its chain ends a polysiloxane block which ends in a trialkylsilyl group, said polysiloxane block corresponding to the formula: [—SiR1R2O—]x-SiR3R4R5, in which R1, R2, R3, R4 and R5 represent alkyl groups having from 1 to 20 carbon atoms, and in which x is a natural integer other than zero.

Abstract: A crosslinkable or crosslinked rubber composition is described which includes a diene elastomer having a mass content of cyclic vinyl units of greater than 15%, and which may be used to form a tire tread. Also described is a tire tread and a tire incorporating the tread. The composition contains a linear or branched diene elastomer derived from at least one conjugated diene, and a reinforcing filler. The elastomer has cyclic vinyl units according to a mass content of greater than or equal to 15% and a number-average molecular weight of from 30,000 to 350,000 g/mol. The elastomer may be obtained by anionic polymerization of one or more monomers including a conjugated diene in an inert hydrocarbon solvent with a catalytic system including an organolithium initiator and a polar agent with several heteroatoms. The reaction may be performed batchwise where the polar agent:initiator molar ratio is greater than 8, or continuously where the polar agent:initiator molar ratio is greater than or equal to 3.

Abstract: The present invention relates to a linear or branched diene elastomer having cyclic vinyl units. A linear diene elastomer according to the invention results from at least one conjugated diene and it comprises cyclic vinyl units in a mass content of greater than or equal to 15% while having a number-average molecular weight falling within a range of from 10,000 to 300,000 g/mol.

Abstract: The present invention relates to a vulcanizable rubber composition which can be used for the manufacture of tires, a process for the preparation of this composition and a tire, the tread of which comprises such a composition, the latter having improved hysteresis and physical properties in the vulcanized state, while retaining satisfactory processing properties.

Abstract: The present invention relates to block copolymers intended to constitute an elastomeric matrix of a cross-linkable rubber composition with reduced hysteresis, to such a rubber composition which is usable in the cross-linked state in a tire tread, to such a tire tread and to a tire comprising said tire tread which exhibits reduced rolling resistance.

Abstract: The present invention relates to a vulcanizable rubber composition which can be used for the manufacture of tires, a process for the preparation of this composition and a tire, the tread of which comprises such a composition, the latter having improved hysteresis and physical properties in the vulcanized state, while retaining satisfactory processing properties. A rubber composition according to the invention comprises a reinforcing white filler, and is such that it comprises at least one diene block polymer which is intended to interact with said reinforcing white filler and which comprises on at least one of its chain ends a polysiloxane block which ends in a trialkylsilyl group, said polysiloxane block corresponding to the formula: [—SiR1R2O—]x-SiR3R4R5, in which R1, R2, R3, R4 and R5 represent alkyl groups having from 1 to 20 carbon atoms, and in which x is a natural integer other than zero.

Abstract: The present invention provides a process for the preparation of a diene elastomer having a reduced amount of vinyl linkages, by anionic polymerization of one or more monomers comprising at least one conjugated diene monomer. The process for preparing the diene elastomer having a reduced amount of vinyl linkages comprises anionically polymerizing one or more monomers comprising at least one conjugated diene monomer in a polymerization medium comprising a hydrocarbon solvent, a polar agent comprising one or more heteroatoms and a monolitiated or polylithiated organolithiated initiator, wherein an organometallic complex of the formula LiAl(R)3(R′), in which Li is a lithium atom, Al is an aluminum atom, and R and R′ are each an alkyl, cycloalkyl or aryl group, is added to the polymerization medium to produce the diene elastomer having a reduced amount of vinyl linkages.

Abstract: The present invention relates to a vulcanizable rubber composition which can be used for the manufacture of tires. The invention also provides for a tire, the tread of which comprises such a composition. The rubber composition posses improved hysteresis and physical properties in the vulcanized state, while retaining satisfactory processing properties in the non-vulcanized state. The rubber composition comprises a reinforcing white filler and a diene block copolymer which is intended to interact with the white filler, the block copolymer comprising a diene block polymer having on at least one chain end thereof a polyether block having a molecular weight of between 1000 g/mol and 3000 g/mol, the polyether block corresponding to the formula: O—CH2—CH2—O)n—R,  (I) in which n is an integer other than zero and R is a saturated or unsaturated hydrocarbon.

Abstract: The present invention relates to block copolymers intended to constitute an elastomeric matrix of a cross-linkable rubber composition with reduced hysteresis, to such a rubber composition which is usable in the cross-linked state in a tire tread, to such a tire tread and to a tire comprising said tire tread which exhibits reduced rolling resistance.

Abstract: The present invention provides a process for the preparation of a diene elastomer having a reduced amount of vinyl linkages, by anionic polymerization of one or more monomers comprising at least one conjugated diene monomer. The process for preparing the diene elastomer having a reduced amount of vinyl linkages comprises anionically polymerizing one or more monomers comprising at least one conjugated diene monomer in a polymerization medium comprising a hydrocarbon solvent, a polar agent comprising one or more heteroatoms and a monolitiated or polylithiated organolithiated initiator, wherein an organometallic complex of the formula LiAl(R)3 (R′), in which Li is a lithium atom, Al is an aluminum atom, and R and R′ are each an alkyl, cycloalkyl or aryl group, is added to the polymerization medium to produce the diene elastomer having a reduced amount of vinyl linkages.

Abstract: The present invention provides a process for preparing a branched diene elastomer having a high proporation of starred chains comprising anionically polymerizing at least one conjugated diene monomer having 4 to 12 carbons in a polymerization medium comprising a hydrocarbon solvent, such as cyclohexane, and an organometallic initiator, such as n-butyllithium, wherein tris-(2,4-di-tert-butylphenyl)phosphite is added to the polymerization medium as a starring agent during or at the end of polymerization in an amount such that the molar ratio of the starring agent to the initiator is between 0.1 and 1.5, preferably between 0.2 and 0.5. The process produces a branched diene elastomer having a high proportion of starred chains. The elastomer can be a homopolymer, such as polybutadiene or polyisoprene or a copolymer, such as polystyrene/polybutadiene.

Abstract: The present invention provides a process for preparing a branched diene elastomer having a high proporation of starred chains comprising anionically polymerizing at least one conjugated diene monomer having 4 to 12 carbons in a polymerization medium comprising a hydrocarbon solvent, such as cyclohexane, and an organometallic initiator, such as n-butyllithium, wherein tris-(2,4-di-tert-butylphenyl)phosphite is added to the polymerization medium as a starring agent during or at the end of polymerization in an amount such that the molar ratio of the starring agent to the initiator is between 0.1 and 1.5, preferably between 0.2 and 0.5. The process produces a branched diene elastomer having a high proportion of starred chains. The elastomer can be a homopolymer, such as polybutadiene or polyisoprene or a copolymer, such as polystyrene/polybutadiene.

Abstract: The present invention relates to a vulcanizable rubber composition which can be used for the manufacture of tires. The invention also provides for a tire, the tread of which comprises such a composition. The rubber composition posses improved hysteresis and physical properties in the vulcanized state, while retaining satisfactory processing properties in the non-vulcanized state.

Abstract: The present invention relates to a vulcanizable rubber composition which can be used for the manufacture of tires, a process for the preparation of this composition and a tire, the tread of which comprises such a composition, the latter having improved hysteresis and physical properties in the vulcanized state, while retaining satisfactory processing properties.

Abstract: A rubber composition which has a reduced hysteresis making it particularly suitable for use as a tread of a tire having reduced rolling resistance, including silica as predominant reinforcing filler and at least one diene polymer bearing, as a chain end, a silanol functional group or a polysiloxane block which has a silanol end.