Degradable collagen/sodium alginate/polyvinyl butyral high barrier coating with water/oil-resistant in a facile and effective approach

Degradable bio-based materials have been widely considered as functional coatings, however, it is a great challenge to fabricate biodegradable coatings with high barrier, water- and oil- resistance. In this work, such coatings were fabricated by using collagen fibers (CF), sodium alginate (SA), and polyvinyl butyral (PVB). CF and SA were mixed evenly and coated on Ca2+ pretreated filter paper. It was mainly due to the electrostatic adsorption between collagen fibers and sodium alginate, and the crosslinking between the adsorption products and Ca2+. By coating PVB solution, the barrier performance was further improved. Notably, the composite exhibited excellent water vapor resistance (48 g/m2·24 h), water resistance (31 g/m2), oil resistance (kit rating: 12/12) and good mechanical properties. This degradable, environmentally friendly, and simple composite paper method has excellent barrier properties, mechanical properties and fluorine-free properties, and will have many applications in the food and packaging fields.