Preparation and physical properties of the polyolefin nano-fibers by melt-electrospinning methods

采用熔融静电纺丝法制备了等规聚丙烯（iPP）纳米纤维。研究了不同分子量和分子量分布的iPP样品的纺丝条件（如电场强度和纺丝温度）对热性能和拉伸性能的影响。结果表明：采用熔融静电纺丝法成功地制备了亚微米级的超细纤维，纤维的平均直径随着电场强度的减弱和分子量的降低而减小;所制备的纳米纤维的DSC图显示了中间相结构的存在;纳米纤维中的iPP链沿纺丝方向取向，这导致高机械强度和低断裂应变。

We prepared isotactic polypropylene (iPP) nanofibers by melt-electrospinning methods. The effects of spinning conditions such as electric field strength and temperature for various iPP samples with different molecular weights and molecular weight distribution on the thermal behavior and on tensile behavior were investigated. We found followings.The fine fibers with the diameter in the submicron order were successfully prepared by melt-electrospinning methods.The average of the fiber diameter decreased with weakening the electric field strength and with decreasing the molecular weight.The DSC charts of the prepared nanofibers showed the existence of the mesophase structure.The iPP chains in the nanofibers were oriented to the spinning direction, which causes the high mechanical strength with the low strain at break.