Production of polybenzimidazole fibers
Abstract
Abstract THE HANDLING DIFFICULTIES PRESENTED BY THE ELONGATION OF A DRY SPUN POLYBENZIMIDAZOLE FIBER ARE OVERCOME THROUGH THE USE OF THE PRESENT PROCESS. MORE SPECIFICALLY, THE ACUTE PROBLEM OF A DRY SPUN POLYBENZIMIDAZOLE FILTER RELAXING AND FALLING FROM A TAKE-UP ROLL OR BOBBIN SOON AFTER SPINNING, AND PARTICULARLY DURING A WASHING STEP, IS OBVIATED BY DRY SPINNING THE FIBER AND IMMEDIATELY THEREAFTER STRETCHING THE FIBER AT A DRAW RATIO OF UP TO 1.5:1 WITH THE STRETCHING STEP BEING CONDUCTED WHILE THE DRY SPUN FIBER IS IN THE PRESENCE OF STEAM OR WATER AT A TEMPERATURE OF AT LEAST 70*C. UP TO ITS BOILING POINT. THE RESULTING POLYBENZIMIDAZOLE FIBER ADDITIONALLY EXHIBITS IMPROVED PHYSICAL PROPERTIES.
Inventors
- 👤 Thomas C Bohrer
- 👤 Arnold J Rosenthal
Bibliographic Details
Claims Analysis
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