Development and Characterisation of Cassava Starch–PVA Bioplastic Films as Sustainable Alternatives to Petroleum-based Plastics

Abstract

This study focuses on the development and characterisation of biodegradable films produced from cassava starch blended with polyvinyl alcohol (PVA) and glycerol. Cassava starch, extracted at a yield of 80.06%, served as a sustainable polymer base owing to its abundance and renewability. Produced films were prepared and characterised in triplicate for each formulation to ensure reproducibility. The films exhibited low water absorption (4%), indicating improved hydrophobicity and structural integrity suitable for packaging applications. Biodegradation tests revealed complete decomposition within 20 - 28 days, with faster rates observed at shallower burial depths due to increased microbial and oxygen activity. Fourier Transform Infrared Spectroscopy (FTIR) confirmed intermolecular bonding and crosslinking through functional groups such as O–H, C=O, and C–O–C. Surface morphology was assessed using Scanning Electron Microscopy (SEM), while thermal stability was evaluated through Thermogravimetric Analysis (TGA/DTG), thereby reducing redundancy in listing characterisation techniques. Thermal analysis showed stability up to approximately 150°C, beyond which major decomposition occurred. Film thickness ranged between 0.18 and 0.27 mm, correlating with starch and glycerol concentrations. The results collectively validate cassava starch-PVA films as eco-friendly alternatives to petroleum-based plastics, offering biodegradability, thermal stability, structural integrity, and suitability for low-temperature short-term applications.