Abstract: .alpha.,.omega.-polymethacrylate dicarboxylic acids of the general formula ##STR1## wherein R.sup.1 is an optionally halogenated alkyl group with 1 to 22 carbon atoms, wherein the R1 group can assume different meanings in the polymer molecule,R.sup.2 is the group of a known chain transfer agent, which has a terminal --COOH croup anda has a value not less than 4. The invention furthermore relates to the synthesis of these compounds and their use as sole or partial components for the synthesis or modification of polyepoxides, polyesters, polyamides, alkyd resins or polyurethanes.