聚丙烯腈湿法纺丝中纤维结构的形成研究

The Formation of Structure of PAN Fibers in Wet-spinning Process of DMSO and Water System

借助于扫描电镜、透射电镜和小角 X 射线衍射方法,研究了聚丙烯腈湿法纺丝中形成的纤维的结构,结果发现:初生纤维是一种高度溶胀立体网络状的冻胶体,立体网络骨架由大分子链束集组成,大分子链间的缠结是骨架的物理交联点,原丝聚集态结构由里向外由3层组成:外表层是极薄的、密实的皮膜,从皮膜向里是柱状皮层,再向里是芯层。纤维沿径向分布的各层具有不同的取向度,随着凝固率和拉伸率的增加,结晶度增加。同时提高凝固液浓度,增加拉伸倍数,增大拉伸速度,可使晶粒增长。

The study on the effect of the structure of PAN fiber on its performance are carried out with the aid of several analysis methods such as scanning electron microscope(SEM),electron probe microscope(EPM),transmis- sion electron microscope(TEM)and X-ray.Results show the protofiber is a high space network and well swollen gel, the space network bone is made up of macromolecule chain structure,the chilled joint is physical conjoint of base.The aggregated structure in precursor is made from three layers:the compact and thin layer outside,the loose layer inside. the column crystallization layer lying in between.The fiber is of different orientation along the diameter distribution. the crystallinty increases as the coagulation and stretch ratio increase,at the same time,enhancing the concentration of spinning dope,increasing the stretch ratio and improving the stretch speed can make the crystal size grow.