Abstract:
With the development of society, the demand for non-toxic and environmentally friendly food packaging materials has been increasing. At this stage, there are few studies on fluorine-free food packaging paper that take into account both water and oil resistance. In this study, a compound oil-proof agent was prepared by cross-linking chitosan solution and sodium alginate solution with ferulic acid, and coated on the food packaging base paper to prepare oil-resistant paper. Then a compound water-proof agent was prepared by using carnauba wax and silica nanoparticles as raw materials, water and oil-resistant paper was prepared by dipping method, and investigated the effects of different mass ratios and coating amounts on the water and oil resistant effect of paper and paper performance. The results show that when the compound mass ratio of chitosan and sodium alginate solution is 8∶2 and the coating amount is 4 g/m
2, the oil-resistant paper can reach the highest oil-proof grade (grade 12). When the compound mass ratio of carnauba wax and silica nanoparticles is 4∶3 and the dipping amount is 3 g/m
2, the water absorption of paper surface (Cobb) value of the paper is 5.93 g/m
2 and the water contact angle is 158.40°, which significantly improves the water and oil-resistant performance of the base paper. In addition, compared with the base paper, the tensile strength of the water and oil-resistant paper shows a raise of 30% and the air permeability shows a reduction of 60%. In short, the preparation process of this study is simple, the raw materials are fluorine-free and environmentally friendly and the coated paper shows better water and oil resistance, which is expected to be applied in food packaging.