Eco-Friendly Food Packaging Barrier Coatings Comprised of Ball-Milled Polysaccharide Polyelectrolyte Complexes

Increasing demand for packaging has motivated research into sustainable materials to prevent continued plastic pollution. Materials based on polysaccharide polyelectrolyte complexes (PPCs) are emerging as a viable solution for packaging applications. We employed ball milling, a well-established technology, for the preparation of PPC materials to create an innovative one-step process capable of producing highly concentrated and homogeneous PPC particle precursor dispersions. We fabricated carboxymethyl cellulose (CMC) and chitosan (CS)-based PPC solutions exhibiting high-solid loading and investigated the potential of PPC solutions made from ball milling as alternative barriers for packaging. PPC-coated paperboard exhibited improved Cobb test performance and outstanding grease resistance as compared to pristine paper. The results certified that a single-step process via ball milling can produce high-solid content PPC solutions useful for creating bio-based coatings with excellent barrier performance. Chitosan (CS) and carboxymethyl cellulose (CMC) powder were mixed in an acidic aqueous solution using a ball mill, enabling one-step fabrication of a homogeneous CMC/CS complex. This biodegradable complex exhibits promising barrier performance as a coating material for food packaging, particularly in terms of grease resistance.image