| 摘要 |
PURPOSE:To obtain a polyurethane resin foam improved in heat-insulation properties and mechanical strengths by reducing the amount of a fluorocarbon causing an environmental pollution as a blowing agent. CONSTITUTION:A polyurethane foam prepared by the normal temperature froth process, wherein the blowing agent used comprises 1,1,1,2-tetrafluoroethane and 1,1-dichloro-2,2,2-trifluoroethane, the total amount of the blowing agents added is 12-30wt.% based on the total weight of the polyurethane resin foam, and the ratio of the 1,1,1,2-tetrafluoroethane to the 1,1-dichloro-2,2,2- trifluoroethane is in the range of 2:8-5:5. |
