Cellular polyurethane and/or polyurea moulding prodn. - involves air injection moulding reactive mixt. in presence of surfactant organo:polysiloxane

摘要

Prodn. of cellular polyurethane and/or polyurea mouldings comprises air-injection moulding a reactive mixt. of a liq. polyisocyanate component with one or more polyols and/or polyamines in the presence of the usual additives and also one or more surfactant organopolysiloxanes of formula R-SiMe2-O-(SiRR'-O)n-SiMe2-R (I). Typical additives are chain lengtheners, crosslinking agents and/or water; and distending agents, fillers, pigments, etc. In (I), each R is an opt. halogen-substd. alkyl, aryl, alkylaryl or a polyether of formula -(CH2)3-O-(C2H4O)x-(C3H6O)y-R" where x is 0-15, y is 1-15 and R" is H or 1-4 C alkyl; R' is Me or -OSiMe3; and n is 3-8 when R' is Me, or 1-4 when R' is -OSiMe3; such that at least (n-1) R gps. denote Me. -