【摘要】 以重均分子量和分子量分布不同的三种聚丙烯树脂为原料,采用熔融挤出-退火-室温拉伸-热拉伸的方法制备了聚丙烯微孔膜。采用凝胶渗透色谱(GPC)、松弛时间谱、差示扫描量热(DSC)、扫描电镜(SEM)等测试手段表征了分子量对最终微孔膜结构的影响。结果表明,重均分子量为587.0 kg/mol、特征松弛时间最长的T30S粒料不易成孔;重均分子量为336.0 kg/mol、特征松弛时间为10-2s~10-1s的T30S粉料微孔膜表面质量差,桥结构少;重均分子量为535.7 kg/mol、特征松弛时间为10-1s~100s的F401适合微孔膜的制备,但需进一步调整工艺。此外,拉伸微孔膜中片晶结构的厚度与微孔分布的区域是成反比的。更多还原

【Abstract】 Three kinds of polypropylene with different weight-average molecular weight and molecular weight distribution were applied to form microporous membranes by melt-extrusion,annealing,cold stretching and hot stretching method in this research.The effect of molecular weight on microporous membranes was characterized by gel permeation in chromatography(GPC),relaxation spectra,differential scanning calorimetry(DSC) and scanning electron microscope(SEM).The results show that T30S particle with weight-average molecular weight(M-w) of 587.0 kg/mol and the longest characteristic relaxation time is difficult to form micropores,the surface quality of the T30S powder(M-w of 336.0 kg/mol,characteristic relaxation time within 10-2～10-1 s) microporous membrane is poor and the bridging structure is less,F401 with M-w of 535.7 kg/mol and characteristic relaxation time within 10-1～100 s is the proper resin to form microporous membranes with a improved method.Moreover,the lamellar thickness of the stretched microporous membranes is in inverse proportion to the micropores distribution region.更多还原