Process for the hot drawing of polybenzimidazole fibrous materials wherein a heated draw surface is employed
Abstract
Abstract POLYBENZIMIDAZOLE FIBROUS MATERIALS ARE KNOWN TO POSSESS AN INHERENT TENDENCY TO ABSORB MOISTURE FROM THE ATMOSPHERE. AN IMPROVED PROCESS IS PROVIDED FOR DRAWING A POLYBENZIMIDAZOLE FIBROUS MATERIAL WHILE IN CONTACT WITH A HEATED DRAW SURFACE (E.G., ONE OR MORE HOT SHOES). IMMEDIATELY PRIOR TO CONTACT WITH THE HEATED DRAW SURFACE THE POLYBENZIMIDAZOLE FIBROUS MATERIAL WHILE IN ASSOCIATION WITH A MINOR QUANTITY OF MOISTURE (E.G., ABOUT 0.5 TO 2 PERCENT BY WEIGHT) IS CONTACTED WITH AN AUXILIARY HEATED SURFACE IN THE ABSENCE OF ELONGATION AND BROUGHT TO A TEMPERATURE BELOW THE GLASS TRANSITION TEMPERATURE OF THE POLYBENZIMIDAZOLE WITH THE SIMULTANEOUS REMOVAL OF MOISTURE. A DRAW TECHNIQUE OF SATISFACTORY STABILITY IS PROVIDED AND A SUPERIOR DRAWN FIBROUS PRODUCT IS PRODUCED.
Inventors
- 👤 A Prince
Bibliographic Details
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