A novel family of functionalized styrenic copolymers that are susceptible to a base-catalyzed beta-elimination reaction is reported. The reactive copolymers, poly{(2-phenyl-2-cyanoethoxycarbonyloxystyrene)-co-(4-hydroxystyrene)}, are prepared by chemical modification of poly(4-hydroxystyrene) using 2-phenyl-2-cyanoethyl chloroformate. A photoresist material consisting of the copolymer and bis[[(2-nitrobenzyl)oxy]carbonyl]-4,4’-trimethylenedipiperidine used as an amine photogenerator affords positive tone images by UV irradiation. The effect of copolymer structure and composition on imaging, thermal stability, and the ease of beta-elimination reaction is discussed.