| 摘要 |
The use of methylene chloride as a blowing agent for resinous foams, particularly urethane foams is improved by incorporating a low molecular weight polyhydroxy aliphatic compound having more than two hydroxyl groups. Simultaneously with the addition the amount of gelling catalyst (e.g., stannous octoate) required to obtain good foam, particularly the very soft foams, is reduced over that required using the methylene chloride without the addition of the polyhydroxy compound. Similarly, when the polyhydroxy compound of this invention is used, smaller amounts of the gelling catalyst are employed for equal foam properties when the fluorinated halocarbons are employed either alone or in combination with the methylene chloride.
|
