Preparation of bioplastic film from chitosan and mango (Mangifera Indica L. Anacardiaceae) kernel starch by casting method

Abstract

The accumulation of plastics in landfills and oceans has encouraged the development of biodegradable plastic products from renewable sources. Natural polymers are excellent candidates that need further modification of their functional and structural properties comparable to conventional plastics. This study aims to fabricate and optimize the formulation of bioplastic films from chitosan and mango kernel starch with glycerol as a plasticizer using response surface methodology (RSM). The chitosan-to-starch mass ratio (1:0.17 to 1:5.83) and glycerol concentration per gram of dry polymer (15.86% to 44.14%) were assigned as the independent variables to design an empirical model that describes the films’ elastic modulus as the sole response. The results yielded an optimal formulation of 1:0.17 chitosan-to-starch mass ratio (2% weight by volume chitosan solution blend) with 15.86% glycerol (per gram of dry chitosan and starch). Reproduction of the optimized film was carried out to validate the empirical model. Characterization of the films’ mechanical and barrier properties, surface morphology, and biodegradability were also investigated in this work. The results suggest that the functional properties of the bioplastic film surpass other chitosan-based bioplastic film blends and can be developed further to become a more sustainable alternative to conventional plastic packaging products.