Synthesis and Characterization of Biodegradable Starch-Based Bioplastics

Abstract

This study was carried out to evaluate the potential of plastic synthesized using bio-based starch. The method began with extraction of starch from chosen tubers with high content of starch; potato and yam. The samples were first grated, grinded and strained to obtain crude starch, which then centrifuged and rinsed to get pure starch. The starch was then reacted with hydrochloric acid to breakdown amylopectin to prevent the starch from becoming plastic-like. Finally, propan-1,2,3-triol was added as a plasticizer to increase the elasticity of the product. The chemical, mechanical, and thermal properties of the products were analyzed using Fourier transform infrared (FTIR), tensile strength tester and Thermogravimetric analysis (TGA). The FTIR spectra of the product displayed the presence of O-H, C-H, C=O and C-O absorption peaks, which indicate the formation of bioplastic has already occured. The tensile strength obtained for potato and yam starch-based bioplastic are 0.6 MPa and 1.9 MPa, respectively. The result gained from TGA showed that 50% weight loss occurred at 250°C for potato and 310°C for yam-based plastic. The highly biodegradability of the plastic was proven using soil burial test, which observed the percentage of soil biodegradation for potato and yam-based bioplastic in 1 week duration is 43% and 26%, respectively. These bio-based plastics have exhibited good thermal and mechanical properties with high biodegradability that makes them a suitable alternative for the existing conventional plastics.