SILICONE SURFACTANTS FOR THE MANUFACTURE OF FLEXIBLE POLYURETHANE FOAMS.

摘要

A siloxane-oxyalkylene copolymer surfactant having the generalized average formula MDxD0yM wherein M represents (CH3)3SiO1/2 or R(CH3)2SiO1/2; D represents (CH3)2SiO2/2; D' represents (CH3)RsiO2/2; and x + y is between 48 and 220, and the ratio x/y is from 5 to 15 inclusive. In the above formulae for M and D', is a polyether containing substituent derived from a CnH2n -initiated polyether and is selected from the group consisting of: (1) -CnH2nO(C2H4O)a(C3H6O)bR' moieties having weight average molecular weights in the range 2300 - 3400 and wherein n is 3-4; the ratio a/b us from 0.5 to 1.3 inclusive; R' represents hydrogen, an alkyl group 1-4 carbon atoms or -C(O)CH3; and (2) -Cn'H2n'O(C2H4O)a'(C3H6O)b'R' moieties having weight average molecular weights in the range750 - 1400 and wherein n' is 3-4; a' is a number such that the ethylene oxide residues constitute 30-100 percent by weight of the alkylene oxide residues of the polyether; b' is a number suchtaht the propylene oxide residues constitute 0-70 percent by weight of the alkylene oxide residues of the polyether; R' represents hydrogen, an alkyl group of 1-4 carbon atoms or-C(O)CH3; and the blend average molecular weight of the overall CnH2n - initiated polyethers is in the range from 1600 to 2400 and the overall EO/P ratio ranges from 0.8 to 1.2. Such siloxane-oxyalkylene copolymer surfactants are useful in the manufacture if flexible polyurethane slabstock foams.