Paper-reinforced sodium alginate/carboxyl methyl cellulose-based bio-composite films

Waste paper-reinforced sodium alginate/carboxymethyl cellulose (NaCMC)-based bio-composite films were prepared by solution casting method by optimum combination of 1.5% sodium alginate and 1.5% NaCMC. The optimum combination was selected on the basis of good tensile strength and low moisture sensitivity. This film was further subjected to aqueous solution of potassium aluminium sulphate (potassium alum) to reduce water vapour permeability and moisture content. This potassium alum solution treatment further enhanced the mechanical and thermal properties, and the film biodegradability was not affected either due to the cross linking or colour addition, which has potential as a substitute for the currently used polyethylene-based films. Molecular interactions between polymers and potassium alum affected mechanical, thermal, and other properties and was confirmed by Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray, and thermo gravimetric analysis of the films. This bio-composite film may be suitable to replace non-biodegradable and costly biodegradable packaging materials.