摘要 |
A method for producing high-tenacity polypropylene fibers with a tenacity greater than 6 cN/dtex and an elongation of less than 40%. To produce as much as possible fibers of a very fine denier, the fiber strands are spun in a first step at a low melting point of less than 250° C., and are withdrawn at a relatively low withdrawal speed of less than 100 m/min., while being simultaneously cooled by a gaseous cooling medium. Subsequently, the fiber strands undergo drawing in at least three draw zones with a total draw ratio greater than 4:1. In this process, the fiber strands are partially drawn in the first draw zone to at least 70% of the total draw. After having been drawn, the fiber strands are cut to a predetermined fiber length.
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