| 摘要 |
PURPOSE:To obtain the subject foam, having a low thermal conductivity, excellent in low-temperature dimensional stability and strength and useful as a heat insulating material, etc., by reacting a specific polyol with a specified foaming agent, a specific organic polyisocyanate, a specified catalyst and a specific foam stabilizer, etc. CONSTITUTION:The objective foam is obtained by reacting (A) an organic polyisocyanate such as diphenylmethane diisocyanate with (B) a polyol partially prepared by reacting an alkylene glycol having >=2 hydroxyl groups and 800-2000 hydroxyl value such as monoethylene glycol with an organic polyisocyanate containing >=2 isocyanate groups such as 2,4-tolylene diisocyanate in an amount of 1/2 equiv. and/or below based on the alkylene glycol used in an amount of 1-70 pts.wt. based on 100 pts.wt. polyol, (C) a foaming agent such as 1,1- dichloro-l-fluoroethane in an amount of preferably 10-70 pts.wt. [based on 100 pts.wt. component (B)], (D) a catalyst, (E) a foam stabilizer and (F) other assistants. |
