OXAZOLIDONE- AND URETHANE GROUPS CONTAINING, ISOCYANATE-TERMINATED PREPOLYMERS, BEING UNDER PRESSURE, FOR ONE-COMPONENT FOAMS.

摘要

A propellent-containing pre-polymer (P) with isocyanate end groups, which also contains oxazolidone and urethane groups and is placed under pressure, is prepared by reacting an isocyanate component (A) with a polyol component (B). (A) comprises a reaction product with isocyanate end groups, prepared by reacting isocyanate(s) (A1) containing two or more isocyanate groups per molecule with a mixture (M) comprising compound(s) (A2) containing groups which are reactive towards isocyanate groups and also containing epoxy group(s) and a polyester polyol (A3). A polyether with a functionality of at least two 2 and containing prim. hydroxyl end groups is used as (B). Also claimed are: (i) the preparation of (P) by reacting (A) and (B) together, (ii) the preparation of a single-component polyurethane foam by frothing decompressed (P) and then leaving it to be cured by atmospheric moisture and (iii) single-component polyurethane foams prepared by this method.