USE OF LOW MOLECULAR WEIGHT POLYHYDROXY COMPOUNDS IN METHYLENE CHLORIDE BLOWN POLYURETHANE FOAMS

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 very soft foams, is reduced over that required using the methylene chloride without the polyhydroxy compound. When the polyhydroxy compound 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.