| 摘要 |
High-temperature resistant cellular polymers are prepared in a one-shot procedure by reacting a polycarboxylic acid or polycarboxylic anhydride with an organic polyisocyanate in the presence of a catalytic amount of a monomeric homocyclic polyepoxide and a tertiary amine. The use of the latter catalyst system permits foam formation to proceed without the need to supply external heat to the reaction mixture after the reactants are brought together. This permits pouring in place of the foam-forming system, for example, in the insulation of cavity walls for construction purposes, in trailer walls, and in cold storage frameworks and the like.
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