Synthesis of a compatibilizer and the effects of monomer concentrations

The aim of this research was to modify Poly (lactic acid) (PLA) and Natural Rubber (NR) using maleic anhydride (MA). The preparation was carried out using internal mixer by free radical melt grafting reaction to produce PLA-g-MA and NR-g-MA as a compatibilizer. The effects of concentrations of MA (3-12 phr) were studied in details. The samples structure of copolymers were then characterized using 1H nuclear magnetic resonance (1H-NMR) and Fourier transforms infrared spectrometer (FTIR). Quantities of grafted MA (% grafting) were characterized by titration analysis and when increasing the monomer used, the quantities of the grafted MA on PLA and NR molecules also increased. The optimum grafting degree for PLA-g-MA and NR-g-MA was at 9 phr of MA with value of 1.63% and 5.02%, respectively