| 摘要 |
PROBLEM TO BE SOLVED: To provide a polyurethane foam having homogeneous fine closed cells. SOLUTION: The polyurethane foam having the closed cells with 10-100μm average cell diameter is produced by reacting a polyol with a polyisocyanate in the presence of a catalyst, a foaming agent and a foam stabilizer. The foam stabilizer is a polydimethylsiloxane-polyalkylene oxide-based graft copolymer having a polyalkylene oxide structure on a side chain, and a polydimethylsiloxane as the main chain. The polyalkylene oxide structure comprises an oxyethylene part (E) and an oxypropylene part (P) regulated so that the molar ratio (E/P) may be >(70/30) and≤(90/10), the average molecular weight of the polyalkylene oxide structure may be 400-1,500, and the average number of the repeating units of the dimethylsiloxane in the polydimethylsiloxane may be 10-150. COPYRIGHT: (C)2007,JPO&INPIT |
