Process for preparing crosslinkable compositions of organosilicon compounds

摘要

Crosslinkable materials are prepared by mixing organopolysiloxane having at least two hydroxyl groups, silane, an organosilicon compound having a radical(s) comprising basic nitrogen, tin catalyst, optionally fillers, and optionally stabilizers, the organopolysiloxanes and silanes forming a reaction product with elimination of alkanol. Preparation of materials crosslinkable with elimination of alcohols to give elastomers comprises mixing: (a) organopolysiloxane having at least two hydroxyl groups; (b) silane of formula RSi(OR 1>) 3(I); (c) an organosilicon compound having a radical(s) bonded to silicon via carbon, the radical further comprising basic nitrogen; (d) a tin catalyst; (e) optionally fillers; and (f) optionally stabilizers, the organopolysiloxanes and silanes forming a reaction product with elimination of alkanol. R : Me, or vinyl radical; R 1>Me, Et radical, and/or their partial hydrolysis products. Silanes (I) and/or their partial hydrolysis products are used in amounts of >= 0.7 parts by weight (pbw), based on 100 pbw organopolysiloxanes. The tin catalyst is added to the organopolysiloxanes or the mixture containing the reaction product only when 1-60 % of the SiOH groups originally present remain present.