Polyamines and processes for the production of such polyamines and of polyurethane plastics therefrom

Abstract

A compound having a terminal isocyanate group is hydrolyzed to produce a polyamine having a urethane and/or a urea and/or a biuret group. More particularly, a carbamate is made by mixing an isocyanate prepolymer having urethane and/or urea and/or biuret groups present with aqueous base solutions at a temperature of from 0.degree. to 0.degree. C. and in quantities such that the equivalent ratio of hydroxyl to isocyanate groups is between from 0.3:1 to .gtoreq.1.01 to 1. The carbamate is then treated with an acid ion exchanger to form an amine. The amine is then removed from any other material which may be present. A preferred polyamine thus-produced corresponds to the general formula: ##STR1## in which each R radical may represent a divalent straight or branched-chain aliphatic radical; a divalent cycloaliphatic radical; a 4,4'- and/or a 2,4'-dicyclohexylmethane radical; or a 2,4- and/or 2,6-methyl cyclohexane radical. Such an amine may be reacted with a polyisocyanate and optionally with other known additives to form a polyurethane plastic or foam.

Dependencies are inferred from the claim text.