碱脲体系对高得率浆淀粉增强性能的影响

The effect of starch on strength of BCTMP with NaOH-thiourea-urea aqueous solution

使用氢氧化钠-硫脲-尿素-水溶液预处理漂白阔叶木化学热磨机械浆,促进纤维之间的结合及纤维表面淀粉的留着以提高纸张强度。通过单因素实验,评估淀粉用量、纸浆浓度、用碱量、冷冻时间对纸张强度的影响情况并探究最佳工艺条件。当淀粉用量为15%、纸浆浓度为15%、用碱量为7%、冷冻时间为45m i n时,该化机浆的增强效果最明显,在打浆度相当的前提下,成纸抗张指数、耐破指数都均较大提升,但耐折度没有明显变化。

In this paper, the bleached chemical thermomechanical pulp of Pinus massoniana was pretreated with NaOH/thiourea/ urea aqueous solution to increase paper strength by improving the combination between fibers and starch. The effects of gelatinized starch dosage, pulp concentration, alkali dosage, and freezing time were evaluated through single factor experiments. The optimumconditions were found to be starch dosage 15%, pulp concentration 15%, alkali dosage 7%, and freezing time 60 rain. Under these conditions, the tensile and burst indices of treated BCTMP could be increased significantly; however, there were no significant effects on the folding strength.