Patent ID: 8540912

Claim:
A process comprising extruding a polymer melt comprising 0.1 to 3% by weight, based on the total weight of polymer, of polystyrene dispersed in poly(trimethylene arylate), through an orifice forming a continuous filamentary extrudate, quenching the extrudate to solidify it into a continuous filament, wrapping the continuous filament around a first driven roll heated to a temperature in the range of 70 to 100° C. and rotating at a first rotational speed, followed by wrapping the filament around a second driven roll heated to a temperature in the range of 100 to 130° C. and rotating at a second rotational speed wherein the ratio of the second rotational speed to the first rotational speed lies in the range of 1.75 to 3; and, thereby forming a spun drawn filament having a denier of ≦3, a denier coefficient of variation of ≦3%, and a birefringence of ≧0.055.