Polypropylene fiber, abbreviated as polypropylene fiber in China. It is a synthetic fiber spun from isotactic polypropylene obtained from propylene polymerization. At present, its production is second only to polyacrylonitrile fiber, and its products mainly include ordinary filament, short fiber, membrane cracked fiber, expanded filament, industrial filament, spinning bonded melt blown nonwoven fabrics, etc.

1. Morphological structure and aggregation structure of polypropylene fiber

Polypropylene fiber is obtained by melt spinning method.  In general, the fiber cross-section is circular and the longitudinal direction is smooth without stripes.

From the molecular structure of isotactic polypropylene, although not as symmetrical as polyethylene, it has high stereoregularity and is therefore more prone to crystallization. The crystallization of isotactic polypropylene is a regular spiral chain, which is a three-dimensional crystal that not only has a regular structure of individual chains, but also has regular chain stacking in the right angle direction of the chain axis.