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摘要

Polyisocyanate-modified dicarboxylic acid (poly)anhydrides (I), which are solid at below 40 degrees C but liq. at above 120 degrees C, are prods. obtd. by reacting org. polyisocyanates with an excess (relative to the NCO/COOH reaction) of free COOH gp.-contg. dicarboxylic acid (poly)anhydrides and opt. also modifying the prods. thus obtd. by reaction with a sub-equiv. amt. (relative to the anhydride gps.) of cpds. contg. anhydride-reactive amino and/or OH gps. Pref. (I) have a COOH gp. content of 0.5-30 wt.%, an anhydride gp. content (as C2O3) of 5-35 wt.% and a N2 content of 0.2-8 wt.%, being obtd. by CO2 splitting-off with NCO/COOH equiv. ratio 0.01-0.6:1 and with the anhydride component being of formula (II) opt. together up to 50 wt.% of the corresp. dicarboxylic acid. In (II), m=1-100; and n=4-16.