Polyhydantoins from unsaturated carboxylic acids and polyiso(thio)cyanates

A process for the preparation of polyhydantoins and polythiohydantoins, comprising reacting organic polyisocyanates or polyisothiocyanates at temperatures of from -20.degree. to +500.degree. C. with compounds consisting essentially of unsaturated carboxylic acid derivatives of the formula:

• ##STR11## wherein R.sup.1 and R.sup.2 are the same or different and each represents hydrogen, halogen, a C.sub.1 -C.sub.20 aliphatic group, a C.sub.7 -C.sub.20 aliphatic-aromatic group, a C.sub.6 -C.sub.20 aromatic group or a hetercyclic group having from 4 to 16 ring members and at least one N, O or S atom;
• A represents CN, COR, substituted or unsubstituted C.sub.1 -C.sub.20 aliphatic group, C.sub.7 -C.sub.20 aliphatic-aromatic group, C.sub.6 -C.sub.20 aromatic group or a heterocyclic group having from 4 to 16 ring members and at least one N, O or S atom wherein the substituents are NO.sub.2, COOR.sub.4, CN, CO or OH;
• R and R.sup.4 are selected from the definition of R.sup.1 and R.sup.2 with the exclusion of halogen;
• M represents OH or ##STR12## and R.sup.6 represents hydrogen, unsubstituted or substituted C.sub.2 -C.sub.20 aliphatic, C.sub.5 -C.sub.12 cycloaliphatic, C.sub.6 -C.sub.20 aliphatic aromatic, or a C.sub.5 -C.sub.12 aromatic or C.sub.5 -C.sub.12 cycloaliphatic containing a heteroatom N, O or S in the ring, wherein the substituents are at least one halogen, C.sub.1 -C.sub.10 alkyl or C.sub.6 -C.sub.12 aryl.