摘要 |
A process for the production of partially oriented polypropylene fibers from syndiotactic polypropylene. Syndiotactic polypropylene is heated to a molten state and extruded to form a fiber preform. The fiber preform is spun at a forward spinning speed within the range of about 700-3500 meters per minute to produce a partially oriented fiber. The partially oriented fiber is wound without further substantial orientation of the fiber at a draw ratio of less than 1.5. By operating at a forward spinning speed of about 700 meters per minute or more, the partially oriented fiber has a greater tenacity than would be observed for a fiber formed from a corresponding spun isotactic polypropylene. The fiber preform is spun at a forward spinning speed of at least 100 meters per minute to provide a tenacity on the order of about 2 grams per denier or more. The fiber preform may be spun at a forward spinning speed of at least 1500 meters per minute to provide a tenacity of about 3 grams per denier.
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