Preparation And Study Of Non-fluorine Greaseproof Paper

Greaseproof paper is a kind of paper that prevents grease from penetrating,mainly used for packing food containing grease.At present,there are two main preparation methods of greaseproof paper:one is to reduce the surface pores of the base paper by improving the pulp beating degree or coating on the surface of the base paper;Second,the use of low surface energy materials to modify the surface of the base paper.Considering the impact of greaseproof paper on food safety and environmental protection,researchers are now focusing on the preparation of greaseproof paper from natural polymer materials.But the greaseproof paper made of natural polymer material has poor greaseproof performance.Therefore,we enhanced the greaseproof performance of chitosan coating by montmorillonite,Therefore,we enhanced the greaseproof performance of chitosan coating by montmorillonite,or prepared greaseproof paper by membrane transfer method to prepare high greaseproof paper.Moreover,by self-assembly on the surface of the base paper to construct a rough structure with mushroom-like,the grease-proof paper with excellent amphiphobicity was prepared.The specific contents are as follows:Montmorillonite was added to chitosan to enhance the oil resistance of chitosan coated paper.JMP statistical software(SAS Institute Inc.,Cary,NC,USA)was used to determine the optimal kit rating and coating load of the paper when the chitosan and montmorillonite concentrations were 2%and 0.1%,respectively.The kit rating of the sample(C2M0.1)reached grade 9 and the oil permeability time reached 290.8 s.While the coating load is higher,the kit rating of C2.5 and C3 coated with chitosan reaches 7 and 8 respectively,and the oil permeability time reaches up to 246.6 s.The greaseproof performance of C2M0.1 is better than C2.5 and C3,so montmorillonite enhances the greaseproof performance of chitosan coating.Using chitosan as raw material,cross linking and in situ precipitation were carried out by sodium polyacrylate solution and sodium hydroxide solution to obtain chitosan film with lower coating load,and then transferred to filter paper with different roughness,to prepare greaseproof paper with different coating load.The greaseproof paper prepared by coating has the highest kit rating of 6,and the oil permeability time is 478.3s at most.While the quantity of film transfer greaseproof paper is only 2.25g/m²,the oil proof grade can reach grade 9,and the oil proof penetration time is about 600 s.With the further increase of membrane quantification,the kit rating reach 12,and the oil permeability time increase to 1800⁺s.The greaseproof performance of film transfer greaseproof paper is better than coating paper.Fluorine-free superamphiphobic paper was prepared by self-assembling mushroom-like microstructure on kraft paper surface.When the content of Fe₃O₄ NPs was 75%,the optimal size of mushroom cap radius and microcolumn spacing was 36.8±18.1?m and 236.6±37.6?m,respectively.The oil contact angle and water contact angle of the sample reached 156°and160.4°,respectively.Milk,ethylene glycol and castor oil also had contact angles of more than150°,and methane diiodide had contact angles of 134.2°.At the same time,all the samples have kit rating of 12,oil permeability time of 1800⁺s.When the content of Fe₃O₄ NPs is 75%,the samples show excellent superamphiphobic and oil resistance properties.