Microporous polypropylene hollow fibers with double layers

Abstract

SYNOPSISMicroporous polypropylene hollow fibers with double layers were prepared by stretching double-layered polypropylene microtubes containing polymethylsilsesquioxane fillers: the relatively smaller filler in the inner layer and relatively larger filler in the outer layer. The resultant hollow fibers have a finely interconnected fibrous structure parallel to fiber axis. Their N2 gas permeabilities were measured to estimate the fibrous structure: tortuosity factor, effective porosity, and pore size. 0 1995 John Wiley & Sons, Inc.

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