| 摘要 |
A process for the preparation of cellular plastics, preferably rigid structural polyurethane foams, by the polyisocyanate polyaddition process involves reacting a) organic and/or modified organic polyisocyanates with b) at least one relatively high-molecular-weight compound containing at least two reactive hydrogen atoms, and optionally c) low-molecular-weight chain extenders and/or crosslinking agents, in the presence of d) blowing agents from the group comprising tertiary alcohols (di), preferably tertiary butanol, or a mixture of at least one tertiary alcohol (di) and water (dii), e) catalysts and optionally f) assistants and/or additives. a |
