n, and (B) from 99 to 10% by weight of at least one member selected from the group consisting of(1) an ester having the structure ##STR6## wherein R1 is hydrogen, an alkyl group having from 1 to 4 carbon atoms, or a halogen, and R2 is an alkyl group having from 1 to 6 carbon atoms, (2) a vinyl ether selected from the group consisting of methyl vinyl ether, ethyl vinyl ether, the propyl vinyl ether