Solvent effects in N‐carboxyanhydride (NCA) polymerization initiated by strong base type initiators

Abstract
The γ‐benzyl‐L‐glutamate N‐carboxyanhydride (NCA) polymerization initialed by diisopropylamine was studied in dimethylformamide (DMF)‐dioxane mixtures of different compositions. It was found that the shape of the conversion versus time plots and the molecular weights of the polymers depend on the solvent composition. Auto‐catalysis is present only when dioxane predominates in the solvent mixtures. Moreover, the molecular weight of the final polymer depends strongly on the precipitation conditions when the polymerization is carried out in DMF.