MELT-SPINNING POLYESTER THROUGH AIR GAP INTO WATER BATH

摘要

Polyester monofilaments of 1000 to 10,000 denier per filament are provided with both good straight tenacity and good transverse properties (high loop tenacity) by extruding molten polyethylene terephthalate of at least 0.6 intrinsic viscosity through an air gap into a water bath to form a monofil and then drawing the monofil in two stages under controlled heating conditions to provide at least 0.190 average birefringence, measured along monofil diameters, and a substantially lower birefringence value adjacent to the surface of the monofil. The monofilaments are suitable for use as reinforcement in tires, V-belts and other industrial applications.