Preferred functional monomers have the general formula wherein R1 is hydrogen, a C1 to C4 alkyl group, or a phenyl group, preferably hydrogen or a methyl group; R2 is a single bond or a divalent linking group that joins an ethylenically unsaturated group to polymerizable or reactive functional group A and preferably contains up to 34, preferably up to 18, more preferably up to 10, carbon and, opti