Process for the vulcanization of polymers

摘要

1,143,956. Vulcanizing unsaturated polyethers or polythioethers. DUNLOP CO. Ltd. (R. T. Woodhams). 17 June, 1966 [10 July, 1965], No. 29337/65. Heading C3R. An unsaturated polymer containing ether or thioether linkages is vulcanized by heating the polymer in the presence of a salt of an N- substituted dithiocarbamic acid of general formula RHN.CSS-. +NH 3 R1 wherein R and R1 are the same or different and are alkyl, aralkyl or aryl groups or of general formula (-R2HN CSS-.+NH 3 R3-) n wherein n is an integer of more than 1 and R2 and R3 are the same or different and are selected from alkylene, aralkylene and arylene groups. In addition sulphur may be present during the vulcanization process. Suitable vulcanizing agents include methyl ammonium methyldithiocarbamate, isopropyl ammonium isopropyl dithiocarbamate, methyl ammonium isopropyl dithiocarbamate and n-butyl ammonium n-butyl dithiocarbamate and are usually used in amounts of from 1 to 10 parts by weight per 100 parts of the polymer. Examples of unsaturated polymers are copolymers of one or more saturated episulphides or epoxides, such as the alkylene sulphides or oxides ethylene sulphide, propylene sulphide, propylene oxide or butylene sulphide, with unsaturated episulphides or epoxides, e.g. alkyl thioglycidyl ether, vinyl thiirane, 1,5- hexadiene monoepisulphide, dimethyl butadiene monoepisulphide, piperylene monoepisulphide, allyl glycidyl ether, 1,4-pentadiene monoepisulphide cyclopentadiene monoepisulphide, limo - nene monoepisulphide, 1,3-cyclohexadiene monoepisulphide, para-methylene-cyclo-hexyl thiirane, thioglycidyl methacrylate and thioglycidyl acrylate. The amount of unsaturated monomer present in the copolymer may be from 0À1 to 20 mole per cent of the total polymer. Preferred polymers include unsaturated copolymers of propylene oxide or propylene sulphide. The polymer composition may contain inert fillers such as carbon black, silica and whiting. Other compounding ingredients may include zinc oxide, zinc sulphide, stearic acid and diethylene glycol.