Patent ID: 8921511
Filing Date: 2014-12-30
Classification: C08G

Abstract:
1. A process for forming a polymer crumb comprising residues of 2-(4-amino phenyl)-5(6) amino benzimidazole (DAPBI), paraphenylene diamine (PPD) and terephthaloyl chloride (TCL), comprising the steps of: i) forming a slurry of b mole percent DAPBI in a solvent system comprising organic solvent and c weight percent of an inorganic salt, wherein the inorganic salt is present in an amount of at least 5 weight percent of the organic solvent; ii) contacting the slurry with a less than stoichiometric amount of terephthaloyl chloride, based on the amount of DAPBI in step i), to form an prepolymer solution; and iii) contacting the prepolymer solution with y mole percent of PPD and additional TCL to form a polymer solution; wherein the total amount of TCL added in steps ii) and iii) is a stoichiometric amount based on the total amount of DAPBI added in step i) and PPD added in step iii); wherein the DAPBI and PPD are added in an amount sufficient for providing a polymer solution having a weight percent solids of 12 percent or greater on a polymer basis and a weight percent solids of 14-25% on a monomer basis; and wherein the sum of y+b is 100 and the product of b×c is 225 or greater.