Morphology of fibers formed via thermally induced phase separation of polypropylene and liquid paraffin blend in stress-field

Phase diagram obtained from small angle light scattering (SALS) and differe ntial scanning calorimetry (DSC) of polypropylene/liquid paraffin blend sys tem indicates that the melts undergo solid-liquid phase separation upon coo ling and liquid paraffin is expelled out of crystalline region of polypropy lene. Fibers spun under high take-up draw ratio are found to be hard-elasti c. Long periods in the meridional direction are observed on the curves of s mall angle X-ray scattering (SAXS), and the yield point of fibers decreases with the increase in liquid paraffin content, which indicates such fibers have row-nucleated lamellar structure perpendicular to the fiber direction. The feasibility of preparing microporous membranes by stretching such fibe rs is investigated.