楮皮纸复配分散剂体系构建及对纸张性能的影响

Construction of dispersant system for kozo paper compounding and its effect on paper properties

关键词:  楮皮纸  分散剂  纸张性质

Key Words:kozo paper  dispersant  paper propertie

摘要:楮皮纤维细胞腔小，其制备的纸张物理性质优异，是书画纸及修复用纸领域不可替代的纤维原料。但其长径比大，使用过程中较难分散均匀，且现有用于促进楮皮纤维分散的纸药成分存在稳定性差、保存难题，进而可能影响楮皮纸的整体品质稳定性。为改善楮皮纸的质量并维持分散剂的性质稳定性，本研究分析了不同种类分散剂（聚环氧乙烯、阴离子型聚丙烯酰胺、羟丙基瓜尔胶、黄蜀葵胶、复配分散剂体系）的粘度、分子量分布，并验证了上述各分散剂对楮皮纤维的分散效果（滤水性能、纸页匀度）及成纸性能（物理性质、润墨性能）。结果表明聚氧化乙烯-羟丙基瓜尔胶-黄蜀葵胶复配的D1分散剂性质最优，其添加量为10%时滤水时间为32 s，放置48 h后粘度仍保持为387 mPa·s，分子量分布变化不明显；未打浆处理楮皮纤维中添加12%D1后，纸张的匀度指数为137，纸张的抗张指数提高16.1%、撕裂指数提高18.5%、耐折次数从51次增加到352次，纸张中墨迹圆形度为0.72，灰度值偏差小，墨迹内部墨色均匀。

Abstract:The paper produced from Broussonetia papyrifera fibers, due to their small cell lumens, exhibits excellent physical properties, rendering it an indispensable fiber material for art and restoration papers. However, the high aspect ratio of these fibers presents challenges in achieving uniform dispersion during use. The stability and preservation of existing papermaking additives designed to facilitate the dispersion of Broussonetia papyrifera fibers are poor, which can potentially impact the overall quality stability of the paper. To improve the quality of Broussonetia papyrifera paper and maintain the stability of the dispersant properties, this study analyzed the viscosity and molecular weight distribution of various dispersants (polyethylene oxide, anionic polyacrylamide, hydroxypropyl guar gum, Abelmoschus manihot gum, and compounded dispersant systems) and verified the dispersion effects of these dispersants on Broussonetia papyrifera fibers (drainage performance, paper sheet uniformity) and papermaking properties (physical properties, ink absorption performance). The compounded dispersant D1, composed of polyethylene oxide, hydroxypropyl guar gum, and Abelmoschus manihot gum, has been found to possess the most favorable properties. When incorporated at a concentration of 10%, it results in a drainage time of 32 seconds, and the viscosity remains stable at 387 mPa·s after 48 hours, with no significant alteration in molecular weight distribution. When 12% of D1 is added to untreated Broussonetia papyrifera fibers, the uniformity index of the paper reaches 137, the tensile index increases by 16.1%, the tear index by 18.5%, and the folding endurance improves from 51 times to 352 times. The ink roundness in the paper is 0.72, with a minor deviation in gray value, and the ink color within the paper is consistent.