Polyimides having pendant hydroxy and acetoxy groups. II. Polyimides derived from bisaminoalcohols

Polyamic acids were prepared from bisaminoalcohols and pyromellitic dianhydride. They were converted to polyimides having pendant hydroxy groups by heating them in toluene or xylene (η inh = 0.22–0.34 dl/g). Treatment of these polyamic acids with a mixture of pyridine and acetic anhydride gave polyimides having pendant acetoxy groups (η inh = 0.22–1.04 dl/g). These acetoxypolyimides were converted to hydroxypolyimides (η inh = 0.20–0.81 dl/g) by an ester‐exchange reaction. Furthermore, the hydroxypolyimides were easily acetylated to give acetoxypolyimides.