Glycopolymers resultant from ethylene–vinyl alcohol copolymers: Degradation and rheological behavior in bulk

Abstract

The physical properties of glycopolymers based on d-(+)-glucosamine, d-(+)-galactosamine and d-(+)-mannosamine derivatives and obtained from two ethylene–vinyl alcohol, EVOH, copolymers with different vinyl alcohol compositions have been analyzed. The thermal degradation of these glycopolymers is almost independent of the type and amount of saccharide incorporated but slightly dependent on the initial EVOH copolymer composition. The glycopolymers derivate from the EVOH copolymer with lower ethylene content present two relaxation processes, while those derivatives from the EVOH copolymer with lower vinyl alcohol composition essentially show three relaxations processes. In both sets of glycopolymers, the relaxation process associated with the cooperative motions that take place at the glass transition is located at analogous temperatures to those previously determined by differential scanning calorimetry, both results being rather consistent.