Starch-g-poly(benzyl methacrylate) copolymers

Abstract

The physicochemical properties such as swel- ling in polar and non-polar solvents, moisture resistance, chemical resistance, ability for gelatinization and the thermal properties along with the evolution of volatile decomposition products of some starch-g-copolymers obtained through the grafting of benzyl methacrylate monomer onto potato starch have been studied. The chemical structure of copolymers was confirmed using ATR–FTIR analysis. The prepared materials were charac- terized by completely different properties than unmodified potato starch due to the covalent bonding of poly(benzyl methacrylate) chains onto starch backbone. The copoly- mers were not able to gelate; however, they exhibited higher swelling in non-polar solvents, lower swelling in polar solvents and higher resistance toward moisture, acid and base conditions than unmodified potato starch. In addition, DSC analysis showed that Tg of copolymers was shifted to a little higher values as compared to Tg of poly(benzyl methacrylate). The thermal stabilities of copolymers and potato starch were comparable. Their decomposition took place in two main stages connected with the emission of various volatile decomposition prod- ucts (CO2, CO, H2O, CH4, aldehydes, alcohols, furan derivatives, acids, benzyl methacrylate) in inert atmosphere as it was confirmed based on the simultaneous TG/DSC/ FTIR analysis. & Marta Worzakow