OPTIMASI RASIO KITOSAN-PATI UMBI UWI DAN PELARUT UNTUK PROSES PEMBUATAN PLASTIK BIODEGRADABEL DARI PATI UMBI UWI (Deoscorea Alata)

Abstract

The quality of biodegradable plastic products from greater yam (uwi) is still low. Efforts to improve thequality of biodegradable plastics using chitosan biopolymers. The purpose of this study: 1). Looking for the optimumconditions for the ratio of the uit and solvent tuber chitosan; 2). Test heat resistance; tensile strength; and testingbiodegradability of biodrgradabel plastics.The method of making biodegradable plastics: uwi tuber starch dissolved in 10% acetone solvent, with a starchsolventratio (b / v): 1:12. Then the plasticizer 3 ml sorbitol was added, and chitosan (varied), stir and heated at 90 0C for20 minutes. The mixture is then poured into the mold, then allowed to stand at room temperature and pressure until aplastic film is formed.The highest tensile strength measurement results were 68.70 N / mm2 with a flexural strength of 349.6% in thecondition of 10% acetone mixture, chitosan 2.5%, (dissolved in 1% acetic acid) and 3 ml sorbitol, with a ratio of starch:solvent 1: 12. Heat resistance at a maximum temperature of 160 0C (charred), and biodegradability period of 20 days.