Sulfur vulcanization of unsaturated reaction products of diisocyanate with linear polyesters and linear polyester-amides and products resulting therefrom

摘要

Vulcanized polymeric products are obtained by heating, with sulphur and a vulcanization accelerator, an organic diisocyanate-modified unsaturated polyester or polyester-amide, i.e. derived from reactants, at least one of which contains an ethylenic or acetylenic linkage. The ingredients are mixed and compounded on a rubber mill. Additional ingredients include: fillers, e.g. carbon black, iron oxide, clay, asbestos, blanc fixe, whiting, lithopone, mica; plastic materials, e.g. natural or synthetic rubber, vulcanized vegetable oils, dark substitute, white substitute, cumar, wood rosin, pitch; detackifying agents, e.g. stearic acid, paraffin wax, oleic acid, lauric acid, dibutyl ammonium oleate; plasticizers, e.g. tricresyl phosphate, dibutyl phthalate, butyl phthalyl butyl glycollate, N-alkyl-toluene sulphonamides; stabilizers or antioxidants, e.g. hydroquinone, N.N1-hexa-methylene - bis - ortho - hydroxy - benzamide, N-phenyl-a -naphthylamine, N-phenyl-b -naphthylamine, a .a .bis - (2-hydroxy-3,5-dimethylphenyl) butane, and small quantities of pigments. Lists of reactants for the initial polyester or polyester amide are given; unsaturated reactants include unsaturated dibasic carboxylic acids and ester-forming derivatives, e.g. maleic, fumaric and hydromuconic acids, maleic anhydride, diethyl fumarate and monomethyl fumarate; specified di-isocyanates are ethylene-, trimethylene-, tetramethylene-, hexamethylene-, decamethylene-, m-phenylene-, p : p1-diphenyl-and naphthalene di-isocyanates. Examples describe the preparation of polyesters or polyesteramides by reacting (1) adipic and maleic acids with glycol; (3) adipic and fumaric acids with glycol; and (4) adipic and maleic acids with glycol and ethanolamine; the polyesters are further reacted with hexamethylene diisocyanate and the products compounded with sulphur, stearic acid, carbon black and zinc diethyl dithiocarbonate and milled at 50-60 DEG C. After milling, the mixture is subjected to pressure in heated moulds. Specification 553,733 is referred to.