GB744256A - Improvements in or relating to telomerization process - Google Patents

Abstract

Distillable telomers of the formula W-(X)n-W or W-(X,Y)n-W, where W is chlorine, bromine or fluorine, X and Y are halo-olefinic monomers and n is greater than 1, are made by telomerizing the monomer or monomers under anhydrous conditions with a sulphuryl halide in the presence of a polymerization catalyst. Suitable monomers are vinyl chloride, bromide and fluoride, vinylidene chloride and fluoride, 2-chloropropene, a -chloro- and -bromo-styrenes, trifluoroethylene, tetrafluoroethylene, tetrachloropropene, chlorotrifluoroethylene, bromotrifluoroethylene, unsym.-dibromodifluoro- and dichlorodifluoro-ethylenes, chlorobutadiene, perfluorobutadiene, perfluorocyclobutene, perfluorocyclobutadiene, phenyl perfluoroethylene, a -methyl-phenyl difluoroethylene and perfluoroacrylonitrile; tetrafluoroethylene with chlorotrifluoroethylene and trichloroethylene or sym.-dichlorodifluoroethylene with chlorotrifluoroethylene or tetrafluoroethylene. The preferred catalyst is benzoyl peroxide activated with sulphur dioxide, but dichlorobenzoyl, di-t-butyl and trichloracetyl peroxides, tetraethyl lead, oxygen and sunlight may be used. The sulphuryl halide may be sulphuryl chloride, bromide or fluoride, fluorosulphuryl chloride or bromosulphuryl chloride. The process may be carried out batchwise, using an inert solvent such as carbon tetrachloride, tetrachlorethylene, tetrachlorethane and 1,2,2-trifluorotrichlorethane if desired, under autogenous pressure, or continuously. The products may be purified by heating to remove excess sulphuryl chloride, solvent and monomer, treating with silica gel, alumina or activated carbon and washed with aqueous ammonia or alkali to remove acids and then fractionally distilled. The liquid, greasy or waxy products may be used as lubricants, hydraulic fluids, heat-transfer media, dielectric fluids, potting compounds, rubber softeners and plasticizers, e.g. for polytetrafluorethylene and polychlorotrifluorethylene. The properties of polychlorotrifluorethylene plasticized with various fractional distillates of its telomer are tabulated.ALSO:Distillable telomers of the formula W-(X)n -W or W-(X, Y)n-W, where W is chlorine, bromine or fluorine, X and Y are halo-olefinic monomers and n is greater than 1, are made by telomerizing the monomer or monomers under anhydrous conditions with a sulphuryl halide in the presence of a polymerization catalyst. Suitable monomers are vinyl chloride, bromide and fluoride, vinylidene chloride and fluoride, 2-chloropropene, a -chloro- and bromo-styrenes, trifluoroethylene, tetrafluoroethylene, tetrachloropropene, chlorotrifluoroethylene, bromotrifluoroethylene, unsym.-dibromodifluoro- and dichlorodifluoro-ethylenes, chlorobutadiene, perfluorobutadiene, perfluorocyclobutene, perfluorocyclobutadiene, phenyl perfluoroethylene, a -methyl-phenyl difluoroethylene and perfluoroacrylonitrile; tetrafluoroethylene with chlorotrifluoro-ethylene and trichloroethylene or sym.-dichlorodifluoroethylene with chlorotrifluoroethylene or tetrafluoroethylene. The preferred catalyst is benzoyl peroxide activated with sulphur dioxide, but dichlorobenzoyl, di-t-butyl and trichloracetyl peroxides, tetraethyl lead, oxygen and sunlight may be used. The sulphuryl halide may be sulphuryl chloride, bromide or fluoride, fluorosulphuryl chloride or bromosulphuryl chloride. The process may be carried out batchwise, using an inert solvent such as carbon tetrachloride, tetrachlorethylene, tetrachlorethane and 1,2,2 - trifluorotrichlorethane if desired, under autogenous pressure or continuously. The products may be purified by heating to remove excess sulphuryl chloride, solvent and monomer, treating with silica gel, alumina or activated carbon and washed with aqueous ammonia or alkali to remove acids and then fractionally distilled. The liquid, greasy or waxy products may be used as lubricants, hydraulic fluids, heat-transfer media, dielectric fluids, potting compounds, rubber softeners and plasticizers. The physical properties of the four-carbon (C4Cl4F6) or six-carbon (C6Cl5F9) chlorotrifluoroethylene telomers are given.