Bei gewoehnlicher Temperatur haertbare Organopolysiloxan-Polykarbonat-Copolymere und Verfahren zu deren Herstellung

摘要

1,175,265. Polysiloxane - polycarbonate copolymers. GENERAL ELECTRIC CO. 22 Dec., 1966 [3 Jan., 1966], No. 57588/66. Heading C3T. Copolymers convertible to the cured, solid, elastic state at room temperature on exposure to moisture, and having attached by C-Si linkages monovalent silyl radicals of the formula Y 3-a -Si-Ra, consist essentially of (A) 1 to 95% (by wt.) of organopolysiloxane blocks composed of R1 2 SiO units, chemically combined with (B) 5 to 99% of the reaction products of HO-ZOH and a carbonyl halide or a diaryl carbonate, wherein Y is a hydrolysable radical, each R is a monovalent hydrocarbon (h.c.) or halo-h.c. radical free of aliphatic unsaturation, each R1 is a monovalent h.c., halo-h.c. or cyanoalkyl radical, Z is R11 or R11WR11, R11 is a divalent h.c. or halo-h.c. radical, W is or a divalent cycloaliphatic, oxy-aryleneoxy, sulphonyl, sulphinyl, oxy or thio radical, R111 is H or R and a is 0, 1 or 2. The copolymers can be made by (1) phosgenating a mixture of (A) HO-Z-OH, and (B) a siloxane of the formula G-(R1 2 SiO) n -R1 2 Si-G, and (C) an unsaturated compound of the formula (2) recovering from (1) a block copolymer containing terminal unsaturated radicals, (3) contacting the resulting copolymer with in the presence of a Pt catalyst, and (4) recovering from (3) the silyl-terminated polysiloxanepolycarbonate copolymer, where G is -OZOH, d is 0 or 1, b is 1 or 2, is part of an aliphatic or cycloaliphatic radical, and n is 1 to 500. Solvents, fillers, e.g. C black, diatomaceous earth, fume SiO 2 , TiO 2 and FeO 3 , and curing accelerators, e.g. Pb and Su octoates and dibutyltridilaurate, can be added to the copolymers prior to curing by exposure to atmospheric moisture. Examples describe the above preparation of the copolymers. Uses-as roof coatings, coatings for Al sidings, flexible windows for vehicles, transparent rubber gaskets for windows, insulating material, rigid or rubbery finish for architectural uses on wood and Cu.