PRODUCTION OF AND DRYING OF COPOLYMER FIBERS

摘要

The present invention concerns processes for reducing water in never- dried fiber comprising copolymer derived from the copolymerization of para-phenylenediamine, 5 (6) -amino- 2 - (p-aminophenyl) benzimidazole, and terephthaloyl dichloride; the process having the following steps in a continuous process, (a) a step of drying a never-dried fiber having at least 0.1% sulfur at less than 150 °C until the moisture content of the fiber is less than 60 weight percent; and (b) a step of further drying the fiber above 150 °C while the moisture content of the fiber is no more than 60 weight percent; and the fiber being further heated to at least 350 °C in either an additional continuous or separate step.