Formulation and Application of Whey-Protein Based Coatings for Improved Paperboard Properties

Abstract

This approach is based on preparation and application of biodegradable-based polymeric coatings onto paperboard surfaces composed of a combination of commercial whey protein and polyvinyl alcohol. Blending of PVA solution with whey protein solution led to improvement in the viscosity of the resultant formula. Low molecular weight polyol (glycerol) was also used as a plasticizer in the formula. Films containing different ratios of whey protein and PVA were prepared and characterized by FTIR. SEM was used to investigate the surface morphology of the prepared films as well as the coated paperboard. It was noticed that film surfaces containing large percent whey protein were rough. Mechanical tests of films and coated paperboard show positive results. Water permeability of coated paperboard by biopolymer blend was improved by approximately 60% compared to uncoated substrate. This work has also explored the recycling potential of barrier-coated boards as an alternative option to disposal in a landfill.