纳米纤维素复合物对再生纸性能的影响.

In this study, we examined the effects of cationic starch（CS） as a reinforcing agent and a binary reinforcement system with nanocellulose（NC） on the reinforcement of recycled paper produced from old corrugated cartons（OCC）. To determine an appropriate dosage of CS, we examined the effects of CS dosage on the performance of OCC recycled paper. Further, using the optimal dosage identified, the effects of its addition on the performance of OCC recycled paper were investigated by adding NC to form a binary reinforcement system. The strengthening mechanism of the CS-NC binary composite system was examined based on a combination of Fourier transform infrared spectroscopy（FTIR）, field emission scanning electron microscopy（SEM）, and thermogravimetric（TG） analyses. The results revealed that CS（1.5%） had the best enhancement effect on OCC recycled paper, with burst, tensile, and tear strengths of hand sheets being increased by 17.62%, 18.18%, and 22.93%, respectively, and air permeability being decreased by 28.55%, compared with the control group. Furthermore, we found that combined treatments with 1.5% CS and NC all enhanced the performance of OCC, with optimal effects being observed when NC was added at a 1% concentration. Compared with the improvements obtained with the sole addition of 1.5% CS, the combined treatment was found to increase the burst, tensile, and tear strengths of OCC recycled paper by a further 5.11%, 11.54%, and 13.46%, respectively, and reduced air permeability by 12.58%. The findings of FTIR analysis revealed that CS can bind to pulp fibers, and that the addition of NC increases the number of hydrogen bonds, thereby facilitating a tighter bonding between fibers. Moreover, SEM observations of the microscopic morphology of the surface of recycled paper indicated that the CS-NC binary system can contribute to a more compact and tighter inter-fiber bonding. In addition, the TG analysis results revealed that by enhancing fiber cross-linking, the CS-NC treatment could increase thermal degradation of the remaining residue of OCC recycled paper to up to 600°C. Our findings in this study indicate that treatment with a combination of CS and NC can significantly enhance the performance of OCC recycled paper. We believe that our results would provide a valuable reference for the repeated recycling of OCC. [ABSTRACT FROM AUTHOR]