COPOLYMER OF SULFUR DIOXIDE AND NUCLEAR-SUBSTITUTED STYRENE DERIV ATIVE

PURPOSE:To provide a linear copolymer which is a two-component copolymer prepared from a nuclear-substituted styrene derivative and sulfur dioxide, having a specific molecular weight, to be used for e.g. resist materials with high sensitivity and high resolution and also high dry itching resistance and high adhesive force to substrates. CONSTITUTION:A distilled nuclear-substituted styrene derivative (e.g. p-t- butoxycarbonyloxyethylstyrene) and t-butylhydroperoxide, etc., are put into e.g. a pressure glass reaction tube followed by mixing and then vacuum deaeration. A dried sulfur dioxide is then put, under cooling, into the reaction system via a vacuum line followed by thoroughly mixing, and the resulting mixture is allowed to react for 20hr in a low-temperature thermostat at -50 deg.C. The resulting reaction mixture is then put into methanol and a precipitate formed is separated, thus obtaining the objective copolymer 2000-2000000 in number-average molecular weight, of structural formula II (p is 1-99; n is 10-10000), made up of (A) l-50mol% of-SO2-structural unit and (B) 50-99mol% of nuclear-substituted styrene derivative structural unit of formula I (R and R are each H, 1-4C alkyl, etc.; R is alkylene; X is OH, t-butoxycarbonyl, etc.).