Multifilament yarns of thermoplastic polymers based on tetrafluoroethylene, and fibers obtained therefrom

摘要

A multifilament yarn of a thermoplastic polymer based on tetrafluoroethylene, having high mechanical strength and dimensional stability at high temperatures (200-250 DEG C), is prepared by melt extrusion through a die characterized by a hole density comprised between 10 and 150 holes/cm<2> and provided with a cooling system of the emerging yarn of high efficiency and uniformity. The multifilament yarn can be subsequently drawn to obtain a fiber with even further improved tensile strength and modulus.