SOFT POLYURETHANE RESIN, AND SOFT POLYURETHANE RESIN MEMBER HAVING EXCELLENT VIBRATION RESISTANCE, DAMPING PROPERTY AND IMPACT ABSORPTION PROPERTY USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a soft polyurethane resin having excellent vibration insulation properties, compressive permanent set and compressive creep properties.SOLUTION: Disclosed is a soft polyurethane resin having excellent compressive permanent set and compressive creep properties with a rubber hardness of 50 or less produced from a composition obtained by reacting the following (A) polyol component and (B) polyisocyanate component. The (A) polyol component is composed of a mixture of polyol having an active hydroxyl group at the terminal with an (A-1) functional group number of 2.5 to 3.5 and a molecular weight of 4,000 to 7,000 and a hyper-branch-polymer having an active hydroxyl group at the (A-2) terminal, and the (B) polyisocyanate component is made of a prepolymer having an active isocyanate group at the terminal obtained by the reaction of polyoxy polypropylene polyol having a functional group number of 2.3 to 3.5 with a polyisocyanate compound.