Design of Polyol for Rigid Polyurethane Foam （spray）

Abstract

Rigid polyurethane foams are used in various fields such as building applications, freezing and refrigerationequipment applications, civil engineering applications, marine vessel applications and the like, due to theirself-adhesive properties and high insulation performance. Energy saving for reducing carbon dioxide emissionsis now an important issue even in the industrial world. And rigid polyurethane foams with high thermalinsulation performance are increasingly required to reduce energy consumption. Since the rigid polyurethanefoam for spraying has self-adhesiveness and can form seamless high insulation layer, it is often used in anapartment or a public building. Though hydrofluorocarbons （HFCs） have high global warming potential, theyhave been used as blowing agents until the present time. But, in recent years, the substitution of HFCs forhydrofluoroolefins （HFOs） which have low thermal conductivity of gas and low global warming potential isprogressing as alternative blowing agent. However, polyol system using HFOs has some problems with storagestability and physical properties of foams. We focused on the solubility of HFOs to polyols, and have developednew polyols with high reaction activity, whose polyol system shows excellent storage stability and improvedphysical properties of foams. In addition, due to aromatic structure of Mannich condensate of these polyols,improvement in flame retardancy of foams can be also expected.Key words : Rigid polyurethane foam, Self-adhesiveness, HFCs, HFOs