摘要:
A method for preparing a polyurethane flexible molded or rigid foam by reacting an organic polyisocyanate with a polyol in the presence of urethane catalyst, water as a blowing agent, optionally a silicone surfactant cell stabilizer, and a cell opener characterized in that the cell opener comprises the reaction product of 1,1,1,3,5,5,5-hepta(hydrocarbyl)-trisiloxane coupled with polyalkyleneoxide mono allyl ether and capped with a C1-C20 hydrocarbyl group-containing succinic anhydride.
摘要:
A method for making a rigid polyurethane foam by reacting a polyisocyanate and a polyol in the presence of a urethane catalyst, a blowing agent and a silicone surfactant characterized by employing as a blowing agent a C1-C4 HFC or HCFC, preferably HFC-245fa, and as the silicone surfactant a polyether-polysiloxane coploymer having a total surfactant molecular weight of 12,000 to 100,000 g/mole, a wt % siloxane in the surfactant of 10 to 40 wt %, a molecular weight of the polyether portion of 1200 to 6,000 g/mole, and a wt % of ethylene oxide in the polyether portion of 30-100 wt %.