# US 5,332,800 A · Cyclic aromatic amide oligomers

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- Number: US 5,332,800 A
- Document ID: US5332800A
- Status: Granted
- Kind: A
- Application number: 08/134,141
- Filed: 1993-10-12
- Granted: 1994-07-26
- Earliest claimed: 1991-04-24
- Assignees: E. I. Du Pont de Nemours and Company
- Inventors: Anthony J. Arduengo, III; Wesley Memeger, Jr.
- Web page: https://patentgrep.com/patent/US5332800A

## CPC

- C07D 255/04: condensed with carbocyclic rings or ring systems
- C07D 257/10: condensed with carbocyclic rings or ring systems
- C07D 259/00: Heterocyclic compounds containing rings having more than four nitrogen atoms as the only ring hetero atoms
- C08G 69/00: Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule (products obtained from isocyanates or isothiocyanates C08G18/00; polyamide-imides C08G73/14)
- C08G 69/32: from aromatic diamines and aromatic dicarboxylic acids with both amino and carboxylic groups aromatically bound
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS

## Abstract

This invention concerns cyclic aromatic amide oligomer compositions and a process for preparing such cyclic oligomers.

## Claims

### Claim 1

A process for the preparation of high molecular weight aramid polymers which method comprises polymerizing cyclic compounds of the formula: ##STR7## wherein: A, B, D and E are independently selected from the group consisting of benzene or benzene derivatives where the substituents on the benzene are alkyl of 1 to about 8 carbon atoms, halide, or alkoxy of 1 to about 8 carbon atoms 3,3'-biphenylene, 4,4'-biphenylene, 1,4-naphthalenediyl, 2,6-naphthalenediyl, oxy-3,4'-diphenyldiyl, oxy-4,4'-diphenyldiyl, methylene-3,4'-diphenyldiyl, methylene-4,4'-diphenyldiyl, sulfonyl-3,4'-diphenyldiyl, and sulfonyl-4,4'-diphenyldiyl;
R is alkyl of 1 to about 8 carbon atoms or cycloalkyl of 3 to about 8 carbon atoms or aralkyl with ar- being phenylene or naphthylene and the alkyl portion of 1 to about 8 carbon atoms; and
n is an integer from 0 to about 12, in the presence of a highly nucleophilic catalyst selected from the group consisting of thiourea, aromatic amines, methyl-3-butylimidazole-2-thione and N-benzoyl-p-phenylene diamine.

### Claim 2 (depends on 1)

The process of claim 1 wherein the nucleophilic catalyst is methyl-3-butylimidazole-2-thione.

### Claim 3 (depends on 1)

The process of claim 1 wherein the nucleophilic catalyst is N-benzoyl-p-phenylene diamine.

### Claim 4 (depends on 1)

The process of claim 1 comprising polymerizing in the presence of a proton source selected from the group consisting of phenyl sulfonic acid, phenylphosphonic acid, phenylphosphinic acid and 2-(2'-pyridyl)ethylphosphonic acid.

### Claim 5 (depends on 4)

The process of claim 4 wherein the proton source is phenylphosphinic acid.