Synthesis and characterization of statistical copolymers of styrene and 4-(1-hydroxyalkyl)styrene

A family of new polymers based on poly(4-(1-hydroxyalkyl)styrene) and its copolymers with styrene were synthesized and thoroughly characterized by 1H-NMR, 13C-NMR, FTIR, and UV spectroscopies. The chemical modification reactions of polystyrene (PS) was used as a novel method of performing the synthesis of poly(4-(1-hydroxyethyl-co-styrene)), poly(4-(1-hydroxypropyl-co-styrene)), poly(4-(1-hydroxybutyl-co-styrene)), and poly(4-(1-hydroxyphenylmethyl-co-styrene)). The novelty of this method lies in the incorporation of the desired mol % of the functional groups in polystyrene chain, to obtain random copolymers of desired composition. In preliminary testing/evaluation studies the utility and versatility of the new copolymers, which have the potential to be negative-tone photoresist materials, were studied. Thus a few photoresist formulations based on poly(styrene-co-4-(1-hydroxyalkylstyrene)) were developed with 5 wt % of a photoacid generator. These studies suggested that the new copolymers synthesized by a simple and alternate method could have the same potential as a photoresist material when compared with the polymers synthesized by the polymerization of the corresponding functional monomer. © 2004 Wiley Periodicals, Inc.