عنوان مقاله [English]
In this work, composites of general-purpose polystyrene and corn starch with glycerol as a plasticizer were prepared in different ratios of starch and glycerol by melt mixing in the twinscrew extruder. The structure of prepared composites was studied using scanning electron microscopy analysis. Also, to evaluate the impact strength and thermal properties of composites, we used Izod impact strength test, melt flow index and Vicat softening temperature tests. Besides, to examine the interaction between composite elements, thermal stability, and degradation process, the samples were subjected to analysis using thermogravimetric analysis. Finally, to study the biodegradation properties, composite samples were buried in soil for 12 weeks and their weight changes were measured during two week periods. Biodegradation results and scanning electron microscopy analysis showed that the rate of biodegradation not only starch present in composites but also depends on the quality of starch particle dispersion. Notched Izod test showed the independence of samples impact strength to starch present. Due to the reduction of stress accumulation points, homogeneous dispersion of starch in the matrix leads to increase impact strength in unnotched Izod test. Melt flow index test showed that addition of starch and glycerol leads to respectively increase and decrease in composites’ viscosity.