【摘要】 本文用电镜扫描,X—射线衍射、透气法和压汞法研究通过熔融纺丝研制的聚丙烯微孔中空纤维的微孔结构。结果表明,要取得满意的微孔结构,关键是在特殊条件下进行低温纺丝成型,使原纤维在准晶态等混晶态存在下进行热处理,使得纤维的准晶态转变为α—晶态,因此使分子链段得到松驰,提高了弹性回复率。最后采取轴向拉伸,使纤维管壁形成一种互相联通的微孔结构。更多还原

【Abstract】 The micro’porous structure of the porous polypropylene hollow filaments which were prepared by melt spinning polypropylene has been studied by scanning electron microscopy,X-ray diffraction,gas permeability and mercury porosymmetr y. The results of the experiments demonstrate that the key to obtain the satisfactory microporous structure is to form the filaments by spinning under a special condition at low temperature.In the presence of mixed crystals,the resultant filaments are subjected to heat treatment and the subcrystals of the filaments are changed into α-crystalline state. Therefore,the chains of the molecules of the filaments relax and the rate of elastic rocovery increase.After axial stretching,the wall of the hollow filaments form the microprous structure which communicates with each other.更多还原