超声波处理对纤维素纤维形态结构的影响

用扫描电镜和光学显微镜研究超声波处理对纤维素纤维形态结构及超微结构的影响。探讨了超声波处理时间、超声波功率、浆浓度等因素对处理效果的影响。研究发现在超声波作用下纤维素纤维形态结构和超微结构变化明显,细纤维化作用显著;其变化程度与处理时间、超声波功率有关,随着超声波处理时间的增加,超声波对纤维素纤维的作用程度提高,更多的次生壁 S2 层微纤维暴露,并发生分丝帚化现象;随着超声波功率的增大,超声波强度提高,空化泡崩溃时产生的微射流对纤维素纤维的冲击作用加强,对纤维形态结构和超微结构产生影响的效应随之增大;确定了超声处理时适宜的浆浓度范围为 1%～3%。纤维素纤维在超声波作用下发生细胞壁层的脱除,使高反应性能的 S2 层微纤维暴露,对提高纤维素的可及度和化学反应性能非常有利。

Morphology Structure Changes of Cellulose Fibers Brought About by Ultrasound Wave Treatment

The influences of ultrasound wave treatment on morphology structure changes of cellulose fibers were investigated by scanning electronic microscopy(SEM) and optical microscopy. The effects of the treatment time, the ultrasound power and the consistency of the slurry on the effectiveness of ultrasound wave treatment were researched. The results show that the morphology structure of cellulose fibers have significantly changed, and partial fibrillation are observed in cellulose fibers. The ultrasound treatment efficiency is greatly affected by treatment time and the power of ultrasound. The extent of structure changes increase and more S2 layer are exposed and fibrillated as the treatment time and power increases. The appropriate consistency of the slurry is 1%～3%. The exposure and the fibrillation of S2 layer contribute much to the enhancement of the accessibility and reactivity of cellulose fibers.