Lingrui Lin,Jie Yang,Shuzhen Ni,Xiu Wang,Huiyang Bian,Hongqi Dai
Generally, the mechanical strength and stiffness of old corrugated cardboard (OCC) waste paper are decreased after multiple recycling procedures. Surface sizing starch , which is extensively used in the surface sizing of paper making, accumulates after dissolving from the fibers and is transformed into pollutant during the OCC re-pulping process. To overcome the pollution and reutilization problem of the waste starch during the recycling process of OCC paper, waste starch was ionized using hydrogen peroxide (H 2 O 2 ) to improve the mechanical properties of OCC paper during the reutilization. The results showed that the carboxyl group of waste starch increased with an increasing degree of ionization, resulting in enhanced copper ion adsorption capacity . Furthermore, the retention rate of the modified starch in the wet-end increased from 18.0% to 48.2%. The OCC paper presented the highest burst index and tensile strength of 8.94 kPa m 2 /g and 112.5 N m/g, respectively, when MS-2 was added. This work has great significance for implementation of the cleaning production of OCC waste papers and the reutilization of the waste starch.
The high-performance retention and drainage systems for papermaking is critical for achieving sustainability in papermaking. This study was aimed at examining the potential of 2,2,6,6-tetramethylpiperidine-1-oxyl oxidized cellulose nanofibrils (TOCNs), characterized by high carboxyl content, strong negative charge, and large specific surface area, as a replacement for colloidal silica (SiO 2 ) in the classic cationic polyacrylamide (CPAM)/SiO 2 /anionic polyacrylamide (APAM) system (CPAM/SiO 2 /APAM) in papermaking. The replacement objective was to improve the retention and drainage performance during papermaking and enhance paper sheet strength. The retention and drainage behavior of the CPAM/TOCNs/APAM system in papermaking and its impact on sheet strength were investigated. The results show that compared with the CPAM/SiO 2 /APAM system, the CPAM/TOCNs/APAM system exhibits superior retention and drainage ability, along with greater sheet strength enhancement. Although the incorporation of hydrophobic cellulose polyglycidyl methacrylate grafted fibers (CPGMAs) slightly reduce sheet strength, it significantly improves the drainage. Moreover, a synergistic effect between CPAM/TOCNs/APAM and CPGMAs on retention and drainage performance is identified. An innovative CPAM/TOCNs/APAM@CPGMAs system was developed to facilitate retention and drainage, achieving 20–30 % higher drainage efficiency, 10–15 % higher filler retention, and enhanced sheet strength than the CPAM/SiO 2 /APAM@CPGMAs system. This system holds prospects for environmentally friendly, efficient, and high-quality papermaking.
危险品化学品经营许可证（带存储）