POLY LACTIC ACID (PLA) DEVELOPMENT USING LACTIC ACID PRODUCT FROM RICE STRAW FERMENTATION WITH AZEOTROPIC POLYCONDENSATION PROCESS

Abstract

Polylactic acid ( PLA) is the raw material for the manufacture of environmentally friendly plastics since microorganisms more easily destroy it in nature. PLA had made from renewable materials such as wood, such as agricultural waste, such as lignocellulose-containing rice straw. Azeotropic polycondensation method has been using for the processing of PLA. This method is relatively simple and can yield a high molecular weight of PLA. Xylene solvent had used to absorb water, and the SnCl2 catalyst has used to accelerate the reaction. The polymerization process lasts 30 hours. The results of the polymerization process were deposited with excess methanol and then filtered with a vacuum pump and then toasted at 800C within 2 hours, resulting in PLA crystals in the form of yellowish-white powder. The best condition is that the 40-gram mass variation produces PLA with a yield of 49.6 per cent PLA, a molecular weight of 57066.9 g / mol and a temperature melting of 120 ° C. The situation had used in the polymerization of fermented lactic acid after achieving the best conditions for the scientific lactic acid polymerization, namely at a lactic acid mass of 40 gr. PLA polymerized lactic acid fermented with rice straw has the characteristics of dark-grey powder with a molecular weight of 2310.86 g / mole and a temperature melting of 135 ° C.