Pet yarns with improved loop tensile properties

摘要

Poly(ethylene terephthalate) monofilaments having improved loop strength and toughness as well as improved tensile strength and tensile toughness. The yarns can have a loop toughness of at least 2 gf/den, a loop tenacity of at least 7 gf/den, a tensile toughness of at least 0.9 gf/den, a tensile tenacity of at least 4 gf/den, and a DSC crystallinity of at least 35%. A process for the production of poly(ethylene terephthalate) monofilaments includes melt extrusion, orientation of the extrudates by stretching, and further stretching as well as heat treating the stretched monofilaments. Industrial fabrics, especially fabrics for paper machine clothing, can be made of such monofilaments as load bearing yarns that resist loop failure and that resist fabric creep at high temperature and high load.