Preparation and Characterization of Sodium Poly(α,l-glutamate)/Poly(ethylene oxide) Macromolecular Complexes

Abstract

Two series of macromolecular complexes of poly(ethylene oxide) (PEO) [100K and 600K]/sodium poly(α,l-glutamate) (PGNA) [MW 1K and 45K] and poly(ethylene glycol) [MW 350−2000]/PGNA [1K] have been prepared by solution blending using water/methanol mixtures. All the macromolecular complexes were soluble in water. The PGNA/PEO macromolecular complexes were mechanically reliable opaque films and may be stretched a couple of fold to form white opaque fibrils. Formation of the α-helical conformation of PGNA in the complexes was determined by CD studies; e.g., the CD spectrum of a film of PGNA 1K−PEO 600K (1:2.5, w/w) complex showed a positive peak at 200 nm and two negative peaks at 207 and 220 nm, indicating the presence of the α-helical PGNA conformation in the complex. FT-IR spectra of the complexes support the presence of the α-helical PGNA conformation in the macromolecular complexes. Wide-angle X-ray diffraction (WAXD) patterns of the PGNA 1K−PEO 600K (1:2.5 and 1:5, w/w) indicate that some of the PEO crys...