The effect of starch-g-copolymers structure on the oxidative behavior studied by the TG/DSC/FTIR-coupled method

Abstract

The effect of starch-g-copolymers structure on the thermal decomposition course under oxidative conditions by using the simultaneous TG/DSC/FTIR technique has been investigated. To those studies, two types of starch-g-copolymers obtained under the graft copolymerization process of aromatic acrylate monomers such as phenyl acrylate and benzyl acrylate onto starch have been chosen. The TG/DSC investigations confirmed that the course of the decomposition process of all studied copolymers under the heating and in the presence of air was similar and run through three large stages. TG/FTIR studies indicated on the same decomposition mechanism under the first decomposition stage, however, on the completely different decomposition mechanism under the second decomposition stage of the copolymers which was directly dependent on the structure of grafted polymer. In addition, it was also proved that the percent grafting of the copolymers has not influenced on its decomposition course and its decomposition mechanism. The grafting percent influenced only on the Δm in each decomposition stage and on the intensity in the emission of the volatile species.