Formation of polyurethane foam in the presence of sulfolanyl-bearing

Abstract

The formation of polyurethane foam including flame-retarded foam is provided employing, as the surfactant component of the foam formulation, a particular class of sulfolanyloxyalkyl-substituted polysiloxane-polyoxyalkylene polymers. The polymers comprise chemically combined monofunctional siloxy units (M.sub.o) and difunctional siloxy units (D.sub.o) and, for every two moles of M.sub.o, an average of from about 2 to about 100 silicon-bonded sulfolanyloxyalkyl groups (Q) and an average of from about 2 to about 30 silicon-bonded polyoxyalkylene blocks (E). The M.sub.o units have at least two alkyls bonded to the respective silicon atoms thereof and the D.sub.o units have at least one alkyl bonded to the respective silicon atoms thereof, the remaining group bonded to silicon of said M.sub.o and D.sub.o units being alkyl, Q or E. When the polyol reactant of the foam formulation is a polyether polyol, the polymers contain from 10 to 200 dialkylsiloxy units and from 2 to 100 Q groups, and the polyoxyalkylene content of E is constituted of from 20 to 75 weight percent oxyethylene. When the polyol reactant is a polyester polyol, the polymers contain zero or up to 20 dialkylsiloxy units and from 2 to 20 Q groups, and the polyoxyalkylene content of E is constituted of at least 75 weight percent oxyethylene.