电纺PAN纳米纤维的AFM形貌及晶区分布研究∗

摘要

There have been a lot of deep researches about the electrospinning of PAN so far.But the works show different viewpoint about the PAN electrospinning and there is few researches about the ordered structure distri-bution of electrospun PAN fibers.The effects of electrospinning parameters in a wider range on the morphology and diameters of polyacrylonitrile (PAN)fibers are studied in detail.The result shows that the solution concen-tration has the greatest effect on the fibers diameter.The fibers’diameter increases swiftly from 288 to 3 469 nm with the PAN concentration increasing from 6% to 18wt%.Ultrasonic etching method,atomic force microscope (AFM),scanning electron microscope (SEM)and X-ray diffraction (XRD)technology have been u-tilized to verify the nature structure of electrospun PAN fibers.The optimal ultrasonic etching conditions were explored.Combining all the results,it is deduced that there are many grooves arranging nearly perpendicular to the fiber axis on the surface of electrospun PAN fibers.The grooves are the amorphous regions (thickness:20-35 nm)and the bulges are the relative ordered regions (thickness:40-190 nm).%目前已有很多学者对聚丙烯腈(PAN)静电纺丝进行了研究,但对其工艺的研究存在不同看法,同时关于电纺PAN纤维有序结构分布的研究较少.针对以上,系统研究了较宽范围内静电纺丝参数对PAN 纤维形貌和直径的影响.经过对比,喷丝液浓度对所制备 PAN 纤维直径影响最大,随着喷丝液浓度从6％(质量分数)升高至18％(质量分数),纤维平均直径由288 nm增大至3469 nm.将超声刻蚀法、原子力显微镜(AFM)、扫描电子显微镜(SEM)结合X射线衍射技术(XRD)对电纺PAN纤维内部结构进行研究.结果表明,电纺 PAN 纤维表面存在相互平行的横向沟槽,其中凸起部分为相对有序区域,宽度约为40~190 nm,凹陷部分为无序区域,宽度约为20~35 nm.