abstract |
A thermosetting composition is provided comprising: (a) a cross-linking agent having at least two functional groups that are reactive with epoxides; and (b) a non-gelled, epoxy functional polymer prepared by atom transfer radical polymerization, in the presence of an initiator having at least one radically transferable group. The polymer contains at least one of the following polymer chain structures: -{(M)p-(G)q}x- or -{(G)q-(M)p}x- wherein M is a residue, that is free of epoxy functionality, of at least one ethylenically unsaturated radically polymerizable monomer; G is a residue, that has epoxy functionality, of at least one ethylenically unsaturated radically polymerizable monomer; 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 independently selected for each structure such that the epoxy functional polymer has a number average molecular weight of at least 250. Also provided by the present invention are methods of coating a substrate using compositions of the present invention and substrates coated by such methods, as well as color-plus-clear composite coatings. |