MECHANICAL TEST AND THERMAL STABILITY ON THERMOPLASTIC SAGO (Metroxylon sagu Rottb.) COMBINATION OF POLYETHYLENE AND POLYPROPYLENE

Abstract

Polyethylene is a polymer that has good elasticity properties, while polypropylene is a polymer with a high tensile strength value. Thus, the combination of these two polymers is expected to increase the value of tensile strength and elasticity. A biocomposite consisting of a mixture of Polyethylene-Polypropylene and thermoplastic sago starch (TPSS) was successfully prepared using the mixing method in an internal mixer. TPSS is made by reacting starch and glycerol with a composition of 65:35 wt.%. Compatibility was made by reacting Polyethylene-Polypropylene: Maleic anhydrate: Benzoyl peroxide with a composition of 88:9:3 wt. %. The match concentration used was 10wt.% based on the TPSS weight. The concentration of the Polyethylene-Polypropylene mixture starts from 0.10,15,20,25,30 and 100wt.%. The characterizations carried out are mechanical properties analysis are tensile strength, elongation at break and elasticity, FTIR analysis, and thermal properties are TGA and DTA. According to the test results, the addition of a mixture of polyethylene and polypropylene can increase the tensile strength from 1.7292MPa (without a mixture of polyethylene and polypropylene) to 4.8334MPa and the elongation at break also increases from 0.23% to 1.72% at a concentration of 30wt.%. Meanwhile, Young’s Modulus decreased from 740 to 281MPa at a concentration of 30 wt. %