Verfahren zur Herstellung von bei Raumtemperatur zu Elastomeren haertenden Organopolysiloxan-Massen

摘要

1,255,587. Organopolysiloxane elastomers; polysiloxanes. WACKER-CHEMIE G.m.b.H. 27 Feb., 1970 [27 Feb., 1969], No. 9659/70. Headings C3S and C3T. A composition which is storage stable in the absence of moisture and which cures to an elastomer on exposure to moisture comprises a hydroxy-terminated diorganopolysiloxane and a compound: R 3 Si(OSiR 2 ) n OSiY 3 (I) in which each R is independently an optionally substituted monovalent hydrocarbon group and each Y which may be the same or different represents a hydrolysable group selected from an acyloxy, hydrocarbonoxy, isothiocyanato, amino, aminoxy, acylamino, aminoalkoxy or oxime group. If n = 0 and Y is aminoxy of formula OY1 where R1 is a monovalent amine or heterocyclic amine radical the composition does not additionally contain 50-99À9% (based on the weight of I) of a difunctional nitrogensilicon material having the structural unit, R1(OY1)Si : where R1 is the same as R or is a triorganosiloxy radical. R is preferably a radical containing not more than 8 carbon atoms and which does not contain a tertiary carbon atom. The organopolysiloxane may have the average general formula: (HO) x (SiR y O (4 _ y)/2 ) m H in which x = 0.99-1.01, y = 1.99-2.01, x + y = 3 and m is at least 3. It may have a viscosity of 100-200,000 cs./25‹ C. I may be used at from 0.5-40% by wt. of the total composition. Conventional fillers pigments and additives may be present. I may be prepared by reacting a compound: R 3 Si(OSiR 2 ) n OSiX 3 (X = halogen) with ammonia, a primary or secondary amine, a carboxylic acid anhydride, an N-substituted hydroxylamine, an acid amide, an aminoalcohol or an oxime in an inert solvent optionally in the presence of a proton acceptor. The Specification describes the preparation of 1,1,1-trimethyl- 3,3,3 - triacetoxydisiloxane and 1,1,1 - trimethyl - 3,3,3 - tricyclohexylaminodisiloxane and (CH 3 ) 3 SiOSi[ONC(CH 3 )Et] 3 by reaction of (CH 3 ) 3 SiOSiCl 3 with acetic anhydride, cyclohexylamine and methylethylketoxime respectively.