X-ray studies on the morphology of zwitterionic polymers

Abstract

Wide Angle X-ray Scattering (WAXS) and Small Angle X-ray Scattering (SAXS) were applied to elucidate the microstructure and morphology of two zwitterionic copolymers. The first system is a sulfobetaine derivative of poly(4-vinyl pyridine) with an ionic content of 10% (10% of the degree of quaternization). The copolymer is almost amorphous, with a small degree of crystallinity (10%). The second copolymer is a N-oxide derivative of the poly(N,N dimethyl aminoethyl methacrylate) highly crystalline (90%). The latter forms superstructures of globular shape with crystalline domains of coordinated polymer-salt systems. X-ray data are in accordance with those published by Castaño et al. [J. Mater. Res. 5, 654 (1990)]. These authors reported TEM micrographs of zwittcrionic systems, where clusters with grainy appearance were observed within the length of scale range found in this work. Models for the morphology of these copolymers are proposed for each use.