COPOLYMER FIBERS AND PROCESSES FOR MAKING SAME

摘要

The present invention concerns yarns comprising copolymer derived from the copolymerization of para-phenylenediamine, 5(6)-amino-2-(p-aminophenyl)benzimidazole; and terephthaloyl dichloride wherein the ratio of moles of 5(6)-amino-2-(p-aminophenyl)benzimidazole to the moles of para-phenylenediamine is 30/70 to 85/15; the yarn having a sulfur content greater than 0.1%; and the hydrolytic strength retention of the yarn is greater than 60%. The invention also concerns processes for making such yarns.