Novel Polyols for All-Water-Blown Open-Cell Rigid Polyurethane Foam

摘要

HCFC-141b and Cyclopentane have been widely used as blowing agents for rigid polyurethane foam market in Japan. In the Japanese rigid polyurethane industry , HCFC-141b is very useful but considered to be the transitional blowing agent which will phase out by 2003 because of its Ozone Depletion Potential(ODP). Therefore, Hydrocarbons (HCs), Hydrofluorocarbons (HFCs) and Water are considered to be the alternatives and the new technologies for replacement have been investigated. These alternatives are all ODP free but have some serious problems respectively in the applications. Hydrocarbons, e.g. cyclo-pentane, is restricted to use only in inflammable place because of its flammability and is now used only in the appliance market. HFC-245fa, typical alternative in HFCs, is nonflammable and reported the foams blown with it have equivalent thermal conductivity to HCFC-141b blown foams, but has higher vapor pressure than that of HCFC-141b.