高得率浆的特性及其对造纸过程湿部化学的影响

Characteristics of High Yield Pulp and Their Effects on the Wet-end Chemistry of the Papermaking Process

与漂白硫酸盐浆(BKP)相比,高得率浆(HYP)含有较多的细小纤维、木素和阴离子垃圾,同时含有较多的羧基和磺酸基等阴离子基团而使其纤维上的负电荷密度显著高于BKP纤维。由于HYP浆与BKP浆在物理和化学性质上的差异,用HYP浆代替部分阔叶木BKP浆对造纸过程的湿部化学将有一定的影响。HYP浆在AKD和松香酯的内施胶过程中的效果优于BKP浆,这得益于HYP纤维的自施胶特性及其较高的阴离子基团含量。添加PEI等阴离子垃圾捕捉剂可以消除HYP浆中的阴离子垃圾对内施胶操作以及助留系统的影响。在优化的湿部条件下,适当添加HYP浆可提高留着率。

Some of the recent results are summarized on the characteristics of HYP and its effect on the wet-end operations of the papermaking process in the production of printing and writing paper, including internal sizing and filler retention. Compared with bleached kraft pulp （BKP）, HYP pulp contains more fines, lignin and anionic trash, as well as more carboxylic and sulfonic groups that impart HYP fibers higher charge density. Due to theses differences in physical and chemical properties between HYP and BKP, substituting HYP for BKP may have some impacts on the wet-end chemistry of the papermaking process. Generally, HYP has higher response to both AKD and rosin ester sizing than BKP due to the higher anionic group content and self-sizing capability of HYP, although HYP fines and anionic trash can affect the sizing adversely. Addition cationic polymers such as PEI can eliminate the negative effect of HYP anionic trash on internal sizing and filler retention. Under the optimized conditions, a partial substitution of BKP with HYP can lead to improved filler retention .