Study on the Effects of Cationic Starch/Nanocellulose Composite System Sizing on the Properties of Paper
Cationic starch(CS)and nanocellulose(NC)were used to construct an CS/NC composite system to explore its application value in food soft packaging materials.In this study,softwood pulp and hardwood pulp with beating degrees of 24 and 36 °SR,respectively,were selected as base paper raw materials.A systematic study was conducted on the effects of intra-slurry/surface sizing the CS/NC composite sys-tem on the properties of paper.When the CS/NC composite system was applied in intra-slurry sizing,CS was added at a mass fraction of 1.0%(relative to the oven dry fiber weight,hereafter)with cellulose nanofibers(J-CNF)of 0.6%,the tensile index and tearing index of the handmade sheet reached 68.6 N·m/g and 7.79 mN·m2/g,respectively,representing increases of 14.1%and 18.8%compared to the base paper.When the CS/NC composite system was applied in surface sizing,the air permeability of sized paper decreased by 99.4%at ce-ment solid content 6.5%,with a mass ratio cellulose nanocrystal(J-CNC)to CS of 1∶9.Additionally,when the amount of single-sided siz-ing was 6 g/m2,the oil-proof grade of sized paper achieved grade 12.