| 摘要 |
<p>The invention pertains to a method for obtaining a composition comprising an aromatic polyamide containing para-phenylene terephthalamide and 2-(p-phenylene)-benzimidazole terephthalamide units by copolymerizing: i) a mole % of para-phenylenediamine; ii) b mole % of 5(6)-amino-2-(p-aminophenyl)benzimidazole; and iii) 90-110 mole % of terephthaloyl dichloride in a mixture of N-methyl pyrrolidone and containing c wt.% of calcium chloride, wherein c is within the range from 1 to 20, and wherein the ratio a: b ranges from 1:20 to 20:1, a+b is 100 mole %, and i), ii), and iii) together comprise 1-20 wt.% of the mixture, characterized in that the product b.c. is less than 215 and that the composition is a crumb with a relative viscosity etarel of at least 4, wherein the crumb is defined as non-sticky particles at least 95% of which having an average diameter of 0.7-15 mm.</p> |
