thermosetting compositions containing polymers with carboxylic functional groups prepared by radical polymerization atom transfer.

A thermosetting composition comprising a solid particulate mixture reactable of: (a) crosslinking agent beta-hydroxyalkylamide and (b) functional polymer polycarboxylic acid, prepared by polymerization of atom transfer radical initiated in the presence of a first initiator having at least one radically transferable group, and wherein said polymer contains at least one of the following polymer chain structures: - [(M) p - (G) q] x and - [(G) q - (M) p] x where M is a residue, that is free of carboxylic acid functionality, of at least one ethylenically unsaturated polymerizable monomer radical; G is a residue, that has carboxylic acid functionality, of at least one ethylenically unsaturated polymerizable monomer radical; p and q represent average numbers of residues occurring in a block of residues in each polymer chain structure, and p, q and x are each individually selected for each structure such that said polycarboxylic acid functional polymer has a number average molecular weight at least 250.