Copolymerization of N‐carboxy‐α‐amino acid anhydride with propylene oxide

Abstract

AbstractThe copolymerization of N‐carboxy‐L(+)‐alanine anhydride (L(+)‐alanine NCA) with DL‐propylene oxide was examined using diethylzinc or triethylaluminum as catalysts. Analytical data, IR and NMR‐spectra indicate that dioxane soluble copolymers contain various kinds of linkage such as amide, ester, ether, and urethane in their polymer chains.Optical rotatory dispersion curves of the copolymers measured in benzene or chloroform were analyzed in terms of the one term DRUDE equation and of the MOFFITT‐YANG equation.The copolymerization of L(‐)‐β‐phenylallanine NCA with DL‐propylene oxide was also examined. The sign of the optical rotation of the copolymer prepared with diethylzinc catalyst was opposite to that of the copolymer prepared with triethylaluminum.