Abstract: An ethylene/butadiene copolymer comprising statistically distributed ethylene units butadiene units, and trans-1,2-cyclohexane units is provided. The molar fraction of ethylene units in the copolymer is greater than or equal to 50%, relative to the total number of moles of ethylene, butadiene and trans-1,2-cyclohexane units. The microstructure of the copolymer is homogeneous. A process for preparing such a copolymer and also to the uses of this copolymer, in particular in rubber compositions for tires, is also provided.

Abstract: An ethylene/butadiene copolymer comprising statistically distributed ethylene units and butadiene units is provided. The molar fraction of the ethylene units in the copolymer is greater than or equal to 50%, relative to the total number of moles of ethylene and butadiene units. The microstructure of the copolymer is homogeneous. A process for preparing such a copolymer and also the uses of this copolymer, in particular in rubber compositions for tires is also provided.

Abstract: A copolymer comprising a copolymer chain A bearing a function B selected from the group consisting of the functions B1 and B2, the copolymer chain A being a copolymer chain comprising monomer units M1 and monomer units M2, M1 being a conjugated diene and M2 being a monomer selected from the group consisting of ?-monoolefins, ethylene and mixtures thereof, B1 being selected from the group consisting of N(SiMe3)2; N(SiMe2CH2CH2SiMe2); para-C6H4(NMe2); para-C6H4(OMe); para-C6H4(N(SiMe3)2); ortho-CH2-C6H4NMe2; ortho-CH2-C6H4OMe; C6F5; C3F7; C6F13; CH(OCH2CH2O); B2 being a function that is derived from B1, is provided. Such a copolymer is synthesized by using a transfer agent bearing the function B1 and a carbon-metal bond, the metal being an alkaline-earth metal, zinc or aluminium.

Abstract: A catalytic system based at least on a preformation conjugated diene monomer, on an organometallic compound as cocatalyst and on a metallocene of formula {P(Cp1)(Cp2)Y} is provided. In the formula, Y denotes a group comprising a metal atom which is a rare earth metal, Cp1 and Cp2, which are identical or different, are selected from the group consisting of fluorenyl groups, cyclopentadienyl groups and indenyl groups, the groups being substituted or unsubstituted, and P is a group bridging the two Cp1 and Cp2 groups and comprising a silicon or carbon atom. Such a catalytic system exhibits an improved stability of the catalytic activity over time, in particular on storage.

Abstract: A copolymer of a 1,3-diene and of an olefin selected from the group consisting of ?-monoolefins, ethylene and mixtures thereof is provided. The copolymer bears, at one of its chain ends, an alkoxysilyl or silanol function, functional group F1, and the copolymer is different from a copolymer of a 1,3-diene and a vinylaromatic monomer.

Abstract: An ethylene/1,3-butadiene copolymer containing ethylene units, butadiene units and UD units of cyclic, 1,2-cyclohexanediyl structure, and bearing, at one of its chain ends, an alkoxysilyl or silanol function, functional group F1 is provided.

Abstract: A process for the synthesis of an ethylene/butadiene copolymer is provided. The process is continuous and comprises: a. feeding at least one stirred polymerization reactor with a mixture of ethylene, butadiene, hydrocarbon-based solvent and catalytic system allowing the formation of cyclic trans-1,2-cyclohexane units in the polymer chain with a mole ratio of ethylene to the sum of the ethylene and butadiene monomers ranging from 0.5 to 0.99; the concentration of ethylene and butadiene monomers in the polymerization reaction medium being at least 10% by weight relative to the total weight; the operating pressure of the reactor is greater than or equal to the saturated vapour pressure of the polymerization reaction medium; b. recovering the ethylene/butadiene copolymer, this copolymer comprising, statistically distributed, ethylene units, butadiene units and trans-1,2-cyclohexane units, the molar fraction of ethylene units in the copolymer being greater than or equal to 50%.

Abstract: The present invention relates to comb block copolymers, combining an elastomeric backbone and rigid pendent blocks and thus having thermoplastic elastomer properties. The invention targets in particular comb block copolymers which may be used as a material as is. According to the invention, the comb block copolymer is a diene/polypropylene thermoplastic elastomer copolymer, characterized in that it consists of a backbone, said backbone being derived from a diene elastomer, and in that it comprises from 5% to 50% by weight, relative to the total weight of the copolymer, of pendent semicrystalline polypropylene groups distributed along the backbone. Another subject of the invention is the process for preparing same, and the compositions comprising same. Finally, a subject of the invention is a tire, one of the constituent elements of which comprises such a composition.

Abstract: A catalytic system based at least on a preformation monomer selected from the group consisting of 1,3-dienes, ethylene, ?-monoolefins and their mixtures, on a metallocene of formula {P(Cp)(Flu)LnG} and on an organometallic compound as cocatalyst is provided. In the formula, Ln denotes a metal atom which is a rare earth metal, G denotes a group comprising the borohydride BH4 unit or denotes a halogen atom X selected from the group consisting of chlorine, fluorine, bromine and iodine, Cp denotes a cyclopentadienyl group of formula C5H4, Flu denotes a fluorenyl group of formula C13H8, P being a group bridging the two Cp and Flu groups and comprising a silicon or carbon atom. Such a catalytic system exhibits an improved stability of the catalytic activity over time, in particular on storage.

Abstract: A polymer comprises randomly distributed units UA, UB, UC and UD and at least one unit bearing a subunit F according to the respective molar percentages m, n, o, p and f F pendant along the chain of the polymer and bearing an associative group comprising at least one nitrogen atom, R1 and R2, which are identical or different, denoting a hydrogen atom, a methyl radical or a phenyl radical which is unsubstituted or substituted in the ortho, meta or para position by a methyl radical, m?50, n?0, o?0, f>0, 0<0+p?25, m, n, o, p and f ranging from 0 to 100, the respective molar percentages of m, n, o, p and f calculated based on the sum of m+n+o+p+f, which is equal to 100.

Abstract: A catalytic system based at least on a preformation monomer which is ethylene or a mixture of ethylene and of a conjugated diene, on a metallocene of formula {P(Cp1)(Cp2)Y} or Cp3Cp4Y and on an organometallic compound as cocatalyst, Y denoting a group comprising a metal atom which is a rare earth metal, the Cp1, Cp2, Cp3 and Cp4 groups, which are identical or different, being selected from the group consisting of fluorenyl groups, cyclopentadienyl groups and indenyl groups, the groups being substituted or unsubstituted, and P being a group bridging the two Cp1 and Cp2 groups and comprising a silicon or carbon atom, is provided. Such a catalytic system exhibits an improved stability of the catalytic activity over time, in particular on storage.

Abstract: A one-pot process for preparing a preformed catalytic system based on a rare-earth metallocene in a hydrocarbon solvent in three performed steps.

Abstract: A catalytic system based at least on isoprene as preformation monomer, on a metallocene of formula {P(Cp1)(Cp2)Y} and on an organometallic compound as cocatalyst, Y denoting a group comprising a metal atom which is a rare earth metal, Cp1 and Cp2, which are identical or different, being selected from the group consisting of fluorenyl groups, cyclopentadienyl groups and indenyl groups, the groups being substituted or unsubstituted, and P being a group bridging the two Cp1 and Cp2 groups and comprising a silicon or carbon atom, is provided. Such a catalytic system is soluble and exhibits an increased stability of the catalytic activity over time, in particular on storage.

Abstract: A rubber composition based on a reinforcing filler and on an elastomeric matrix comprising a highly saturated diene elastomer, comprising units of the following categories A, B, C, D and E, or units of these same categories A, B, C, D and E comprising, for at least one of the categories B, C, D and E, a mixture of at least two different units of the same category which differ from one another through the nature of their side groups Ri: and where R1, R2, R3 and R4, which are identical or different, denote a hydrogen atom, a methyl radical or a phenyl radical which is substituted or unsubstituted in the ortho, meta or para position by a methyl radical; R5 denotes a hydrogen atom or a methyl radical; R6 denotes a methyl radical or a phenyl radical which is substituted or unsubstituted in the ortho, meta or para position by a methyl radical; m, n, o, p and q are numbers ranging from 0 to 100.

Abstract: A compound and the use thereof to prepare a functional or telechelic polyolefin is provided. The compound has the following formula (II): Y((CH2)p—B?)m??(II), wherein m=2 or 3; Y being an alkaline earth metal or zinc when m=2, Y being aluminum when m=3; B? being selected from the group comprising N(SiMe3)2; N(SiMe2CH2CH2SiMe2); C6F5; C3F7; C6F13; para-C6H4—NMe2; para-C6H4—O-Me; para-C6H4—N(SiMe3)2; and CH(OCH2CH2O); and p being an integer from 0 to 50.

Abstract: The present invention relates to a rubber composition based on a reinforcing filler and on an elastomer matrix comprising a highly saturated diene elastomer comprising at least five distinct units of A, B, C, D and E distributed randomly within the elastomer at respective molar fractions of m %, n %, o %, p % and q %, where m+n+o+p+q=100; m?50; n+o+p+q?10; and 15?p+q?2. This rubber composition enables a satisfactory degree of stiffness to be reached while maintaining hysteresis properties acceptable for use in the manufacture of tires for running vehicles.

Abstract: An ethylene/butadiene copolymer comprising statistically distributed ethylene units butadiene units, and trans-1,2-cyclohexane units is provided. The molar fraction of ethylene units in the copolymer is greater than or equal to 50%, relative to the total number of moles of ethylene, butadiene and trans-1,2-cyclohexane units. The microstructure of the copolymer is homogeneous. A process for preparing such a copolymer and also to the uses of this copolymer, in particular in rubber compositions for tires, is also provided.

Abstract: An ethylene/butadiene copolymer comprising statistically distributed ethylene units and butadiene units is provided. The molar fraction of the ethylene units in the copolymer is greater than or equal to 50%, relative to the total number of moles of ethylene and butadiene units. The microstructure of the copolymer is homogeneous. A process for preparing such a copolymer and also the uses of this copolymer, in particular in rubber compositions for tires is also provided.

Abstract: A copolymer comprising a copolymer chain A bearing a function B selected from the group consisting of the functions B1 and B2, the copolymer chain A being a copolymer chain comprising monomer units M1 and monomer units M2, M1 being a conjugated diene and M2 being a monomer selected from the group consisting of ?-monoolefins, ethylene and mixtures thereof, B1 being selected from the group consisting of N(SiMe3)2; N(SiMe2CH2CH2SiMe2); para-C6H4(NMe2); para-C6H4(OMe); para-C6H4(N(SiMe3)2); ortho-CH2-C6H4NMe2; ortho-CH2-C6H4OMe; C6F5; C3F7; C6F13; CH(OCH2CH2O); B2 being a function that is derived from B1, is provided. Such a copolymer is synthesized by using a transfer agent bearing the function B1 and a carbon-metal bond, the metal being an alkaline-earth metal, zinc or aluminium.

Abstract: A catalytic system based at least on a preformation conjugated diene monomer, on an organometallic compound as cocatalyst and on a metallocene of formula {P(Cp1)(Cp2)Y} is provided. In the formula, Y denotes a group comprising a metal atom which is a rare earth metal, Cp1 and Cp2, which are identical or different, are selected from the group consisting of fluorenyl groups, cyclopentadienyl groups and indenyl groups, the groups being substituted or unsubstituted, and P is a group bridging the two Cp1 and Cp2 groups and comprising a silicon or carbon atom. Such a catalytic system exhibits an improved stability of the catalytic activity over time, in particular on storage.