Augmentation of physico-mechanical, thermal and biodegradability performances of bio-precipitated material reinforced in Eucheuma cottonii biopolymer films

Abstract

Green reinforcement in biopolymer for enhanced industrial application is on the increase. Bio-precipitated CaCO3 was synthesised via the process of microbially-induced calcium carbonate precipitation using Bacillus sp. strain. The bio-precipitated CaCO3 (B-PCC) and conventional CaCO3 precipitates (C-PCC) reinforcement effect on the properties of Eucheuma cottonii film was analysed and compared. The biocomposite films were fabricated using a solvent casting technique. The physicomechanical, thermal and biodegradability performances of B-PCC and C-PCC incorporated E. cottonii film with increasing fillers' contents [0.05, 0.10, 0.50, 1.00, 2.00 (wt.%)] were determined and compared through a range of testing include water vapour permeability (WVP), contact angle using sessile drop method, scanning electron microscopy (SEM), tensile, elongation, Young's modulus, thermogravimetric analysis (TGA), and soil burial test. A further comparison was made between the E. cottonii biocomposite film with the existing biodegradable mulch films to evaluate its potential application using wet cup method. Results revealed that biocomposite films embedded with 0.1% B-PCC appeared to exhibit higher water barriers and hydrophobicity behaviours than those embedded with C-PCC. However, the mechanical strength and thermal stability were slightly lower than those embedded with C-PCC. E. cottonii biocomposite films, especially those embedded with 0.1 wt. % B-PCC has shown the potential in agricultural mulch film as it promoted better biodegradation and tensile strength by 34.24% and 20% respectively compared to the existing biodegradable PLA/PBAT mulch film, making it a promising alternative to the conventional plastic to mitigate plastic pollution.