Abstract: The present invention provides a method for the production of a copolymer based on vinyl aromatic compounds and conjugated dienes, in which after polymerization, the copolymers are treated with multi-functional sulfur halides in the presence of a catalyst at temperatures in the range from 20 to 130° C. The copolymers produced according to the present invention demonstrate clearly improved processing characteristics as a result of selective masticating effect and good mechanical properties.

Abstract: This invention relates to a process for the production of polydienes having controlled Mooney viscosity, carried out by means of catalysts based on rare earth compounds, which is characterized in that the conjugated dienes used are polymerized in the presence of from 0.005 to 80 wt. % of 1,2-dienes, based on the sum of conjugated dienes used and of 1,2-dienes used. The polydienes thus produced are used particularly in the manufacture of car tires.

Abstract: The present invention provides a method for the production of a copolymer based on vinyl aromatic compounds and conjugated dienes, in which after polymerization, the copolymers are treated with multi-functional sulfur halides in the presence of a catalyst at temperatures in the range from 20 to 130° C.

Abstract: A catalyst comprising(a) a reaction mixture formed by reacting M(RCO.sub.2).sub.3 with AlR.sub.3.sup.1,(b) AlR.sub.3.sup.2 and/or HAlR.sub.2.sup.2 and(c) a Lewis acidwherein M denotes a trivalent rare earth element with an atomic number of 57 to 71, R denotes a saturated or unsaturated, straight chain or branched chain alkyl group having 1 to 20 C-atoms which may be substituted one or more times with cycloalkyl having 5 to 7-atoms and/or phenyl, the carboxyl group being attached to a primary, secondary or tertiary C-atom; a cycloalkyl group having 5 to 7 ring carbon atoms, which may be substituted one or more times with alkyl groups having from 1 to 5 C-atoms; or an aromatic group having from 6 to 10 ring carbon atoms, which may be substituted one or more times with alkyl groups having 1 to 5 C-atoms, and R.sup.1 and R.sup.2 are identical or different, straight chain or branched chain alkyl groups having from 1 to 10 C-atoms. Said catalyst may be used for polymerizing diene monomers in solution.

Abstract: A catalyst comprising(a) a reaction mixture formed by reacting M(RCO.sub.2).sub.3 with AlR.sub.3'.sup.1(b) AlR.sub.3.sup.2 and / or HAlR.sub.2.sup.2 and(c) a Lewis acidwherein M denotes a trivalent rare earth element with an atomic number of 57 to 71, R denotes a saturated or unsaturated, straight chain or branched chain aliphatic hydrocarbon group having 1 to 20 C-atoms which may be substituted one or more times with cycloalkyl having 5 to 7-atoms and/or phenyl, the carboxyl group being attached to a primary, secondary or tertiary C-atom; a cycloalkyl group having 5 to 7 ring carbon atoms, which may be substituted one or more times with alkyl groups having from 1 to 5 C-atoms; or an aromatic group having from 6 to 10 ring carbon atoms, which may be substituted one or more times with alkyl groups having 1 to 5 C-atoms, and R.sup.1 and R.sup.2 are identical or different, straight chain or branched chain alkyl groups having from 1 to 10 C-atoms.

Abstract: A process for the production of strictly alternating copolymers of trans-1,4-butadiene and propylene units by the solution copolymerization of butadiene and propylene with vanadium-containing organometallic mixed catalysts, wherein vanadyl dialkoxy halides of which the alkoxy groups are branched in the 2-position to the oxygen atom are used as the vanadium compounds.

Abstract: Uranium-containing mixed catalysts containing uranium in the formal oxidation state +4 as uranium salts of carboxylic acids, a Lewis acid, and an organometallic aluminum compound are prepared and can be used for stereospecific polymerization of diolefins or mixtures of diolefins and monoolefins.

Abstract: A mixture of polyolefin resins and partially crosslinked ethylene-propylene sequential polymer and/or ethylene-propylene-diene sequential polymer representing a so-called thermoplastic rubber having improved properties.

Abstract: Polysegment copolymers with thermoelastomeric properties are obtained by a process, wherein block polymers of the idealised form S.sub.x -B.sub.y, in which S represents structural units derived from styrene, B represents structural units derived from a conjugated diene and x and y are integers, are reacted with sulphur chlorides.The products according to the invention are suitable for the production of shoe soles, hoses, industrial rubber articles and particularly hot melt adhesives.

Abstract: A vulcanization system for natural and/or synthetic rubber containing light fillers comprising certain silanes, thiazoles, guanidines, and thiurams. By using this system the extremely unpleasant odor of silanes when used alone can be substantially diminished without affecting the properties of the vulcanizate.

Abstract: Process for the homopolymerisation and copolymerisation of conjugated dienes in inert organic solvents on alkali metal amides as catalysts in the presence of a solvating agent for the amide.