| abstract |
A copolymer includes (i) a plurality of ethylenic moieties A having a structure according to the formula: n n n n n n n n n n n n wherein R 2 and R 3 independently represent hydrogen, a halogen, an optionally substituted linear, branched, or cyclic alk(en)yl group, or an optionally substituted aromatic or heteroaromatic; (ii) a plurality of acetal moieties B having a structure according to the formula: n n n n n n n n n n n n n n n n wherein L 1 represents a divalent linking group, x=0 or 1, and R 1 represents an optionally substituted aromatic or heteroaromatic group including at least one hydroxyl group; and (iii) a plurality of acetal moieties C and/or moieties D which include a structural moiety including a chromophoric group having its main absorption in the infrared region. |