Wet-spinning process for {37 dog-bone{38 {0 shaped acrylonitrile polymer fibers
Abstract
Abstract In a wet-spinning process for spinning acrylonitrile polymer fibers from a spinning solution of said polymer in a concentrated aqueous sodium thiocyanate solvent, said process comprising extruding said spinning solution through orifices directly into a cold aqueous coagulating bath to form filaments, pulling the freshly-coagulated filaments away from the orifices, followed by washing, stretching, drying, and relaxing said filaments; the improvement comprising forming such fibers having dog-bone or dumbbell cross-sectional configuration by use of the following conditions; said spinning solution contains 9 percent to 13 percent by weight of acrylonitrile polymer dissolved therein; said aqueous coagulating bath contains 22 percent to 28 percent by weight of sodium thiocyanate dissolved therein; said rectangular orifices each have a long dimension between about 450 and about 700 microns and a short dimension such that the resulting filament spun therefrom has an aspect ratio between 3.0 and 4.0; and said pulling, washing, and stretching steps are operated at a denier-speed product per filament of between 75 and 850 denier-meters per minute.
Inventors
- 👤 A Maranci
Bibliographic Details
Claims Analysis
Total Claims: 1References Cited (Backward Citations)
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