Effect of hydrochloric acid concentration as chitosan solvent on mechanical properties of bioplastics from durian seed starch (durio zibethinus) with filler chitosan and plasticizer sorbitol

Abstract

The production of starch based bioplastic from durian seed as polymer matrix with addition of chitosan as filler and sorbitol as plasticizer were investigated. The aim of this research to obtain the effect of hydrochloric acid concentration as chitosan solvent on the mechanical properties of bioplastics included tensile strength, elongation at break, modulus young, functional group using FT-IR, surface morphology using SEM. Starch is the raw material for bioplastics which extracted by the durian seeds, then characterized to determine its chemical composition. The method of bioplastic production used in this research was casting method. Variation of hydrochloric acid concentration used 0.9%v, 1.0%v, 1.1%v, 1.2%v and 1.3%v. Bioplastic were analyzed physical and chemical properties. From the analysis, best condition of bioplastics obtained at hydrochloric acid concentration 0,9%v with temperature 70 °C for tensile strength 10,629 MPa, elongation at break 8,207%, and modulus young 129,514 MPa. From the results of FT-IR analysis indicated O-H group and N-H group on bioplastics due to the addition of chitosan and sorbitol. The results of mechanical properties were supported by Scanning Electron Microscopy (SEM) showed the bioplastic with chitosan as filler and plasticizer sorbitol have the fracture surfaces were a bit rough and jagged.