Process of forming aramid copolymer

Abstract

The invention concerns processes for forming a polymer comprising residues of 2-(4-amino phenyl)-5 (6) amino phenyl benzimidazole (DAPBI), paraphenylene diamine (PPD), and terephthaloyl dichloride, comprising the steps of: (a) forming a slurry of DAPBI in a solvent system comprising an organic solvent and an inorganic salt; (b) adding less than a stoichiometric amount, relative to the amount of DAPBI, of terephthaloyl dichloride to the slurry; (c) agitating the slurry to react the DAPBI and terephthaloyl dichloride to form an oligomeric solution; (d) adding PPD to the oligomeric solution and agitating until essentially all of the PPD is dissolved, followed by the addition of terephthaloyl dichloride to form a prepolymer solution; and (e) allowing the prepolymer solution to form a polymer.

Description

technical field [0001] This patent application relates to a process for the preparation of aromatic polyamide polymers derived from 5(6)-amino-2-(p-aminophenyl)benzimidazole (DAPBI), p-phenylenediamine (PPD) and terephthaloyl dichloride (TCl), capable of forming fibers with excellent physical properties. Background technique [0002] Derived from 5(6)-amino-2-(p-aminophenyl)benzimidazole (DAPBI), p-phenylenediamine (PPD) and terephthaloyl dichloride (TCl or T, also commonly known as p-phenylene Diformyl chloride) fibers are known in the art. Such copolymers are high-strength fibers made in Russia (for example, under the trade name with )Foundation. See Russian Patent Application 2,045,586. The two amines on DAPBI differ greatly in terms of reactivity and positional factors. The amine shown on the right side of the structure below (azole amine) is an order of magnitude more reactive than the amine on the left side of the structure (benzylamine). Therefore, by t...

AI Technical Summary

Problems solved by technology

Therefore, by the conventional polymerization method, in NMP / CaCl 2 DAPBI / PPD copolymers prepared in solvent systems tend not to have control over the position of the monomer components

Images