POLYISOCYANATE-MODIFIED POLYCARBOXYLIC ACIDS

摘要

A process for preparing polyisocyanate-modified polycarboxylic acids by conversion of anhydride-group-free polycarboxylic acids with isocyanate- functional compounds. The process includes reacting A) an anhydride-group-free polycarboxylic-acid component with B) an isocyanate-functional component having an (average) isocyanate functionality of at least 1.8, at an equivale nt ratio of carboxylic acid groups to isocyanate groups of from 1.2:1 to 120:1. The polyisocyanate-modified polycarboxylic acids are solid below 40 .degree.C an d liquid above 130 .degree.C, and have an average carboxylic acid functionality of at least 1.8, a content of free carboxylic acid groups of from 4.0 wt.% to 80.0 wt.% and a content of amide groups of from 0.4 wt.% to 32.5 wt.%.