Zwitterionic polymers with carbobetaine moieties

A series of new monomeric and polymeric carbobetaines based on acrylamides has been synthesized and characterized. Due to long hydrocarbon substituents, the compounds have chemical structures of surfactants and polysoaps, respectively. Results are compared with those of analogous poly(sulfobetaine)s. The poly(carbobetaine)s are more hygroscopic and show improved solubility. Viscometric studies in ethanol show no, or only weak, polyelectrolyte behaviour. Thermal stability is decreased, and glass transitions occur at lower temperatures. X-ray diffractograms indicate the presence of superstructures whose detailed forms depend on the polymers' geometry.