Mechanical Strength of Polystyrene-Starch Polyblend Using Jatropha Oil Epoxide Plasticizers

Abstract

Polyblend is a physical mix between two or more polymers resulting in different properties to get degradable polymer and better mechanical properties. Starch is degradable polymer, but polystyrene is synthetic polymer which is difficult to degrade. Polyblend polystyrene-starch will make the polymer easily to degrade but low mechanical properties. To increase the mechanical properties of polyblend, the plasticizers is needed. The plasticizers in this experiment was epoxide of jathropha oil. The polyblend of polystyrene-starch was prepared with various compositions, i.e. 0; 2.5; 5.0; 7.5; and 10.0%. The density of the polyblend decreased with the addition of the plasticizers. The reduction of density shown that jathropha oil epoxides can be used as plasticizers. The mechanical properties showed that the additions of plasticizer could increase the elongation and reduce the tensile strength. Thermal analysis using differential scanning calorymetry showed that glass transition temperature decreased from 95.37 ºC to 91.79 ºC.