Abstract: The present invention relates to a process for producing polymers comprising repeating units derived from at least one isoolefin monomer, at least one multiolefin monomer and optionally further copolymerizable monomers in the presence of at least one organic nitro compound and AlCl3/water wherein the process is conducted in the absence of compounds selected from the group consisting of vanadium compounds, zirconium halogenid, hafnium halogenides. Preferably the polymers have a multiolefin content of greater than 2.5 mol %, and a molecular weight Mw of greater than 240 kg/mol.

Abstract: The present invention relates to a process for producing polymers comprising repeating units derived from at least one isoolefin monomer, at least one multiolefin monomer and optionally further copolymerization monomers in the presence of at least one organic nitro compound and AlCl3/water wherein the process is conducted in the absence of compounds selected from the group consisting of vanadium compounds, zirconium halogenid, and hafnium hallogenides.

Abstract: Hydrogenated copolymers of an unsaturated nitrile, butadiene and isoprene, wherein the molar ratio of butadiene to isoprene is less than 3:1, display valuable low temperature properties.

Abstract: The present invention relates to a process for producing polymers comprising repeating units derived from at least one isoolefin monomer, at least one multiolefin monomer and optionally further copolymerizable monomers in the presence of at least one organic nitro compound and AlCl3/water wherein the process is conducted in the absence of compounds selected from the group consisting of vanadium compounds, zirconium halogenid, hafnium halogenides.

Abstract: Hydrogenated copolymers of an unsaturated nitrile, butadiene and isoprene, wherein the molar ratio of butadiene to isoprene is less than 3:1, display valuable low temperature properties.

Abstract: A solution polymerisation process carried out continuously in a cascade produces high molecular weight gel-free ethylene terpolymers having on the one hand high resistance to fuels, oils and organic solvents and on the other hand high flexibility even at low temperatures when narrow ranges are adhered to in respect of solvent content, pressure, temperature control and degree of conversion.

Abstract: High molecular weight, gel-free ethylene/vinyl acetate copolymers may be prepared by the process of solution polymerization if a particular relationship of temperature/pressure is observed.

Abstract: The invention relates to a polychloroprene rubber which shows advantages over the prior art in the sum total of its performance properties, namely vulcanization rate, tensile strength, elongation at break, modulus, tear propagation resistance and thermal stability of the vulcanizate.

Abstract: Thermoplastic moulding compositions consisting ofI. 75 to 99.5% by weight of a polymer ofA. 0 to 95% by weight, 95% or less by weight; of a graft copolymer prepared by grafting polymerization ofA.1 5 to 95% by weight of a mixture ofA.1.1 50 to 95% by weight of styrene, .alpha.-methylstyrene, nuclear-substituted styrene, methyl methacrylate or mixtures thereof andA.1.2 50 to 5% by weight of (meth)acrylonitrile, methyl methacrylate, maleic anhydride, N-substituted maleimide or mixtures thereof onA.2 95 to 5% by weight of a rubber with a glass transition temperature Tg or <0.degree.C., andB. 100 to 5% by weight of a thermoplastic polymer ofB.1 95 to 50% by weight of styrene, .alpha.-methylstyrene, nuclear-substituted styrene or methyl methacrylate or mixtures thereof andB.2 5 to 50% by weight of (meth)acrylonitrile, methyl methacrylate, maleic anhydride, N-substituted maleimide or mixtures thereof andII. 25 to 0.5% by weight of a hydrogenated nitrile rubber.

Abstract: An advantageous process for the heterogeneous catalytic hydrogenation of nitrile group-containing unsaturated polymers retaining nitrile groups, is characterised in that palladium supported on alkaline earth metal carbonates is used as hydrogenation catalyst.

Abstract: Storage-stable polychloroprene is obtained, using a polymerization initiator comprising a mixture of(1) a redox system comprising(a) a reducing agent selected from the group consisting of(i) sodium dithionite,(ii) formamidine sulphinic acid, and(iii) a mixture from (i) and (ii),(b) potassium peroxodisulphate as an oxidizing agent and, optionally,(2) sodium anthraquinone-.beta.-sulphonate as a co-activatorin the presence of oxygen, wherein from 10 to 90 by weight of the initiator are present at the commencement of polymerization and the remainder is added during the polymerization, and after a certain degree of conversion the reducing agent is the only component of redox system (1) which remains to be added.

Abstract: A: Thermoplastic moulding materials made from a vinyl chloride homopolymer or copolymer containing at least 50% by weight of vinyl choloride units,B: a graft polymer, prepared by graft polymerization ofB1: 50 to 85 parts by weight of a mixture of at least two of the monomers styrene, acrylonitrile, methyl methacrylate and .alpha.-methyl styrene onB2: 50 to 15 parts by weight of an at least partially crosslinked butadiene or acrylate rubber having average particle diameters of 0.08 to 1 .mu.

Abstract: 2,3-Dichlorobutadiene-(1,3) is obtained from 2,3,4-trichlorobutene-1 by dehydrohalogenation in the presence of a phase transfer catalyst, an inhibitor and oxygen according to an improved process in which the aqueous solution of an alkali metal hydroxide is added to the mixture of trichlorobutene, catalyst, inhibitor and optionally water, and the reaction is carried out at a temperature of from -10.degree. to +60.degree. C. under an inert gas which contains from 0.1 to 8% by weight of oxygen.

Abstract: An improved process of polymerizing an aqueous emulsion of chloroprene monomer stabilized with phenothiazine wherein polymerization is initiated in the presence of phenothiazine stabilizer and molecular oxygen with a polymerization initiator comprising sodium dithionite.

Abstract: A process for the production of polychloroprene mixtures of sol and gel polymers in a ratio, by weight, of rom 1:4 to 9:1, the gel polymer being produced by radical emulsion polymerization from chloroprene in the presence of 4 to 10% by weight of water soluble disproportionated abietic acid, and the sol polymer being produced by radical emulsion polymerization of chloroprene in the presence of not more than 3.5% by weight of a water soluble disproportionated abietic acid with the polychloroprene mixture containing at most 3.8% of said acid.

Abstract: In order to control noxious substances in the air, the air to be monitored is continuously drawn through an absorber. An absorber with a suction pump connected downstream is used for this purpose. A particularly small and compact device composed of an absorber and suction pump may be obtained by forming the inlet valve and outlet valve of the suction pump as O-ring disc valves and by providing the pump drive with a light barrier.

Abstract: Thermoplastic moulding compositions of 20 to 90% by weight of polyvinyl chloride and, accordingly, 10 to 80% by weight of a mixture of(1) 20 to 100% by weight of a thermoplastic resin which is a copolymer of 30 to 40 parts by weight of .alpha.-methyl styrene, 52 to 62 parts by weight of methyl methacrylate and 4 to 14 parts by weight of acrylonitrile, and(2) 0 to 80% by weight of a graft polymer of 40 to 60 parts by weight of a monomer mixture of styrene (40 to 60 parts by weight), acrylonitrile (0 to 10 parts by weight) and methyl methacrylate (40 to 50 parts by weight), on 40 to 60 parts by weight of polybutadiene or butadiene/styrene copolymer containing up to 30% by weight of copolymerized styrene.