Poly(meth) acrylimides of improved color

Abstract

A polymer useful for preparing moldings and comprising essentially units of the formula I ##STR1## where R.sup.1 and R.sup.2 are each hydrogen or methyl, and R.sup.3 is hydrogen, C.sub.1 -C.sub.18 -alkyl, C.sub.5 -C.sub.8 -cycloalkyl, C.sub.6 -C.sub.10 -aryl or C.sub.6 -C.sub.10 -aryl-C.sub.1 -C.sub.4 -alkyl, each of which may be monosubstituted, disubstituted or trisubstituted by radicals selected from the group consisting of C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy and halogen, is obtainable by reacting a polymer based on C.sub.1 -C.sub.20 -alkyl esters of (meth)acrylic acid with a primary amine of the general formula II R.sup.3 NH.sub.2 II in the presence of a compound selected from the group consisting of phosphinic acid and phosphonic acid and their alkali metal, alkaline earth metal, aluminum and ammonium salts, wherein the ammonium ion can be monosubstituted, disubstituted, trisubstituted or tetrasubstituted by C.sub.1 -C.sub.4 -alkyl and/or C.sub.5 -C.sub.8 -cycloalkyl, or mixtures thereof.

Dependencies are inferred from the claim text.