纤维素纳米晶体提高箱纸板强度性能的研究

Improving the Strength Properties of Liner Board by Cellulose Nanocrystal

关键词:  废纸浆  纤维素纳米晶体  阳离子淀粉  阳离子聚丙烯酰胺  增强剂  强度性能

Key Words:recycled pulp  cellulose nanocrystal  cationic starch  cationic polyacrylamide  strengthening agent  strength properties

摘要:本研究以废纸浆为原料，采用硫酸水解法制备纤维素纳米晶体（CNC），并将其用于箱纸板的增强。结果表明，所制备的CNC呈典型的棒状结构，其直径和长度范围分别为11~23 nm和115~240 nm，长径比为5∶1~22∶1，Zeta电位为-56.37 mV，CNC聚集态呈纤维素I型结构，结晶度为71.1%，热稳定性较废纸浆略有降低；在CNC用量为3%的一元增强实验中，箱纸板的抗张指数、撕裂指数、耐破指数、环压指数和耐折度分别为30.5 N·m/g、6.22 mN·m²/g、1.55 kPa·m²/g、9.18 N·m/g和3次；将2%阳离子淀粉（CS）和阳离子聚丙烯酰胺（CPAM）分别与3%CNC复合形成二元增强体系时，箱纸板的抗张指数、撕裂指数、耐破指数、环压指数和耐折度较CNC一元增强时分别提高了30.5%、4.1%、12.7%、11.6%、33.3%和21.9%、3.5%、12.3%、10.6%、33.3%。

Abstract:In this study， cellulose nanocrystal （CNC） was prepared by sulfuric acid hydrolysis from recycled pulp and applied to enhance the liner board. The results showed that the prepared CNC displayed a typical rod-like structure with a diameter and length of about 11~23 nm and 115~240 nm， respectively， the aspect ratio was 5∶1 to 22∶1 and Zeta potential was -56.37 mV. The aggregation state of CNC presented cellulose I structure with the crystallinity of 71.1%， and its thermal stability was slightly lower than that of recycled pulp. In the reinforcement experiment with 3% CNC dosage， tensile index， tearing index， burst index， ring crush index and folding endurance of liner board were 30.5 N·m/g， 6.22 mN·m²/g， 1.55 kPa·m²/g， 9.18 N·m/g and 3 times， respectively. Then， 2% cationic starch （CS） and 2% cationic polyacrylamide （CPAM） were combined with 3% CNC respectively to form the binary reinforcement systems， tensile index， tearing index， burst index， ring crush index and folding endurance of liner board were further increased by 30.5%， 4.1%， 12.7%， 11.6%， 33.3% and 21.9%， 3.5%， 12.3%， 10.6%， 33.3% compared to those of 3% CNC dosage respectively.