Silicone surfactants for the production of open cell polyurethane flexible foams

摘要

A method for preparing a polyurethane flexible foam which comprises reacting an organic polyisocyanate with a polyol in the presence of urethane catalyst, water as a blowing agent, optionally a cell opener, and a polydimethylsiloxane cell stabilizer composition which comprises at least 90 wt% of polydimethylsiloxane molecules having the formula:        Me₃Si(OSiMe₂)_nOSiMe₃where n is 5 to 7, provided at least 15 wt% of each of the three molecules in which n is 5, 6 and 7 is present.