Effect of Epoxidized Natural Rubber on Properties of Poly (butylene Succinate)/Rice Flour Composites

Abstract

Composites made from poly (butylene succinate) (PBS) and rice flour (RF) were successfully prepared in this work. In order to study the effect of rice flour content and epoxidized natural rubber (ENR-50) on properties of composites, PBS/rice flour composites were prepared by varying rice flour contents as follows: 0, 1, 5, 10, 20 and 25 percent by weight with using ENR-50 as a compatibilizer (5 phr). The utilization of epoxidized natural rubber (ENR-50) as a compatibilizer of PBS/rice flour composites was also determined in this study. All materials were mixed by using a two-roll-mill at 165 °C and then processed into specimens using an injection molding machine. Test specimens were characterized phase morphology, rheological and mechanical properties, including tensile properties and impact strength by using scanning electron microscope (SEM), capillary rheometer, tensile testing machine and impact testing machine, respectively. Results indicated that tensile strength, elongation at break, and impact strength of composites were continuously decreased with increasing rice flour content while tensile modulus was increased. The maximum improvement of tensile modulus was achieved at 20 percent by weight of rice flour. This may be attributed to the stiffening effect of rice flour itself. Additionally, using ENR-50 at 5 phr as a compatibilizer of PBS/rice flour composites results in enhancement of shear viscosity, elongation at break and impact strength of the PBS/rice flour composites remarkably, due to the better interfacial adhesion between PBS and rice flour and elastomeric behavior of ENR-50.