| 摘要 |
PURPOSE:To solve the problem of friability and poor dimensional stability of a rigid polyurethane foam produced using water as a blowing agent without using a chlorofluorocarbon blowing agent which pollutes the environment. CONSTITUTION:A foamable polyurethane compsn. which contains 100 pts.wt. polyol mixture consisting of 40wt.% or higher arom. polyamine polyol having a hydroxyl value of 300-500, 15wt.% or higher ethylenediamine-based polyol having a hydroxyl value of 400-500, 5-35wt.% arom. polyester polyol having a hydroxyl value of 200-500, and 5-35wt.% sorbitol-based polyol having a hydroxyl value of 300-450 and 3-7 pts.wt. water as a blowing agent. |
