POLYPROPYLENE FIBERS AND FABRICS

摘要

This invention relates to polypropylene fibers and fabrics containing polypropylene fibers, the fibers comprising propylene polymers comprising at least 50 mol% propylene, said polymeis having: a) a melt flow rate (MFR, ASTM 1238, 230°C, 2.16kg) of about 10 dg/min to about 25 dg/min; b) a dimensionless Stress Ratio / Loss Tangent Index R2 [defined by Eq. (8)] at 190 °C from about 1.5 to about 30; c) an onset temperature of crystallization under flow, Tc rheoi (as determined by SAOS rheology, 190 °C, 1 °C/min, where said polymer has 0 wt% nucleating agent present), of at least about 123 °C; d) an average meso run length determined by 13C NMR of at least about 55 or higher; and e) optionally, a loss tangent, tan6, [defined by Eq. (2)] at an angular frequency of 0.1 rad/s at 190 °C from about 14 to about 70.