PAN/DMSO溶液的挤出对初生纤维结构的影响

Effect of PAN/DMSO solution extrusion on structure of as-spun fiber

应用扫描电子显微镜（SEM）和x射线衍射仪（XRD）研究了在一定的凝固条件下，挤出剪切速率（γ）对聚丙烯腈（PAN）初生纤维聚集态及形态结构的影响规律。结果表明：随着γ的增加，初生纤维的结晶度增大，晶粒尺寸减小；初生纤维的表面上产生了沿着轴向分布的沟槽，γ越高，沟槽越深，初生纤维的截面结构变得不均匀，出现了一些大孔和皮芯结构；随着γ的增加；初生纤维中的二甲基亚砜（DMSO）残留量增加。控制γ在11721—14651s-1，PAN／DMSO溶液流动性能好，可获得表面沟槽均匀、缺陷少、晶粒尺寸小且结晶度高的结构致密的PAN初生纤维。

The influence irregularity of shearing rate （ γ ） on the aggregate structure and morphology of polyacrylonitrile （PAN） as-spun fiber was studied under a specific coagulation condition by scanning electron microscopy （SEM） and X-ray dif- fraction （XRD）. The results showed that the crystallinity of as-spun fiber was increased and the crystal size was decreased while increasing γ. The grooves formed on the fiber surface along with the axis. The higher γ was, the deeper the grooves were. The cross section structure of the as-spun fiber became uneven and some big holes and the sheath-core structure appeared. The dime- thyl sulfoxide （DMSO） residual content in the as-spun fiber was increased while increasing γ. The PAN/DMSO solution had ex- cellent flowability as γ was controlled as 11 721 -14 651 s-1, from which the PAN as-spun fiber can be obtained with even sur- face grooves, less defects, low crystal size, high crystallinity and compact structure.