| 摘要 |
<p>PURPOSE: To provide a multifilament yarn of thermoplastic polymer based on tetrafluoroethylene having a very high mechanical strength, particularly a high tensile strength and a low shrinkage at high temperatures, and to provide a fiber obtained from the yarn. CONSTITUTION: This multifilament yarn, 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 10-150 holes/cm<2> and provided with a cooling system of the emerging yarn of high efficiency and uniformity. The multifilament yarn is subsequently drawn to obtain a drawn multifilament yarn with even further improved tensile strength and modulus.</p> |
