Abstract: The compound (Cp*.sub.2 YCl).sub.2 wherein Cp* is pentamethylcyclopentadienyl and its preparation and use for the polymerization of olefins is disclosed.

Abstract: Articles made from amorphous dipolymers of perfluoro-2,2-dimethyl-1,3-dioxole with tetrafluoroethylene having high glass transition temperatures of 140.degree. C. or higher, low indices of refraction, and good physical properties, and low dielectric constants, include, among others, substrates for circuit boards, composites, sheets and films, optical lenses, and electronic current carrying devices.

Abstract: The invention relates to solutions of fluoropolymers which preferably contain carbonate groups, in solvents of the general formula (I) ##STR1## These solutions are suitable, in particular, for the production of membranes for liquid permeation processes, such as electrolysis.

Abstract: Chlorinated polyethylene resins which are semicrystalline yet of sufficiently low viscosity to be processible on conventional extrusion equipment are provided. The resins may be used in a variety of applications such as membranes, either theromplastic or thermoset, wire and cable jackets and the like. Plasticizers and other viscosity-reducing aids need not be used in conjunction with these resins.

Abstract: Process for inhibiting crust formation in reactors used for polymerising alpha-olefines, such as ethylene and propylene, in the presence of particles of catalytic solids containing titanium and chlorine in the combined state.The polymerisation is carried out in the presence of an amount of a silicone oil which is less than 1% by weight, relative to the weight of catalytic solid.

Abstract: A flexible brazing alloy tape with a binder having less than 3% by weight total organic content and no more than about 1% by weight residual ash after melting is provided by use of a polyacrylic acid polymer, glycerol and water as a vehicle in which the powdered alloy is dissolved to form a slurry prior to casting. The polyacrylic acid polymer has a relatively low viscosity defined by a molecular weight of about 450,000. The slurry is deposited on a substrate and is dried and the resulting flexible low organic self-supporting tape is removed from the substrate to be formed into desired shapes as preforms for brazing. Alternatively a brazing alloy tape comprising a binder having a similarly low total organic content is produced by mixing the powdered alloy with polyvinyl alcohol, glycerol and water and thereafter casting the tape as described above.

Abstract: In a process for dyeing synthetic polyamide fibre materials with metal-free acid dyestuffs a dye liquor is used which contains compounds of the formula ##STR1## wherein R.sub.1 represents an alkyl and/or alkenyl radical with 12-22 carbon atoms,R.sub.2 represents hydrogen and/or methyl,m represents 0 or 1,n represents 2 or 3 andThe sum of x + y + z represents a number from 10-30, and compounds of the formulaR.sub.3 -- B -- XwhereinR.sub.3 represents an alkyl radical with 12-22 carbon atoms and/or a phenyl or/and naphthyl radical which contains a total of 12-22 carbon atoms and is substituted by one or more alkyl radicals,B represents --O--SO.sub.2 -- and/or --SO.sub.3 andX represents hydrogen or an ammonium, alkali metal, alkaline earth metal, mono-, di- or tri-alkyl-ammonium or hydroxyalkylammonium ion with, in each case, 1-4 carbon atoms in the alkyl radical, or represents a cyclohexyl-ammonium ion.

Abstract: First polymerization of a mixture of styrene-type monomers and conjugated diene monomers containing 30 to 70% by weight of styrene-type monomers is carried out, and when 40 or more of the diene monomers have been converted to a copolymer, there are then added styrene-type monomers in such an amount that the content of styrene units accounts for a proportion of 70 to 85% by weight of the finally obtained block copolymers, followed by completion of the polymerization. Alternatively, when all the diene monomers added have been converted to the copolymer, the second polymerization of styrene type monomers is carried out in the presence of a small amount of conjugated dienes as a polymerization retardant. Block copolymers obtained thus are useful for sheet or film molding having good low-temperature impact strength.