PAN纤维致密性与油剂渗透的相关性研究

通过调整成纤条件改变PAN纤维的致密程度,经后续的上油工序制得含有油剂的PAN纤维。采用体密度表征纤维的致密程度;借助直流电弧原子发射光谱(DC-Arc-AES)和电子探针(EPMA)分别表征Si原子含量及其微区分布;借助孔分析和粒度分析分别表征PAN纤维中的孔径分布和油剂分子的粒径。结果表明,油剂分子的平均粒径小于纤维的平均孔径,通过范德华力作用吸附于纤维表面,并从纤维表面的开孔渗透进入纤维内部,到达纤维的芯部。凝固浴温度升高,纤维的致密性下降,渗透进入纤维内部的油剂分子数量增加。凝固浴浓度上升、预牵伸倍数提高,纤维的致密性增加,渗透进入纤维内部的油剂分子数量减少。

The relationship between the compactness of PAN fibers and the permeation of silicone oil

The compactness of PAN fibers has been varied by employing different conditions for fiber formation before applying silicone oils.Compactness was studied by bulk density measurements;the content of Si and its microdistribution were characterized by direct current-arc-atomic emission spectroscopy(DC-Arc-AES)and electron probe microanalysis(EPMA),respectively.The pore size distribution of PAN fibers and size distribution of silicone oil molecules were measured.The results showed that the average size of the silicone oil molecules was smaller than the average pore size,and silicone oil molecules were adsorbed by van der Waals forces onto the fiber surface and then permeated inwards through open pores and became impregnated into the core.With increasing coagulation temperatures,the compactness decreased and the number of silicone oil molecules inside the fibers increased.When the coagulation concentration or pre-draft multiple were increased,the compactness increased and the number of silicone oil molecules decreased.The compactness of PAN fibers can be enhanced by reducing the coagulation temperature,raising the coagulation concentration or increasing the pre-draft multiple,so as to prevent silicone oil molecules from permeating inwards.