Single-stage melt polymerization process for the production of high molecular weight polybenzimidazole
US4312976A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 15, 1980 |
| Grant date | Jan 26, 1982 |
| Priority date | — |
| Expiry date | Jul 15, 2000 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G73/18
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A single-stage melt polymerization process for the production of high molecular weight polybenzimidazole is provided. The process comprises reacting a monomeric reactant or reactants, which are capable of reacting to form a polybenzimidazole, at a temperature above the melting temperature of the monomeric reactant or reactants in the presence of a catalyst selected from the group consisting of organic sulfonic acids, halogenated acetic acids, and non-oxidizing inorganic acids. The polybenzimidazole is preferably produced by the reaction of 3,3',4,4'-tetraaminobiphenyl with isophthalic acid at a temperature within the range of approximately 360.degree. C. to 425.degree. C. for a period of time within the range of approximately 3 to 5 hours in the presence of approximately 0.25 to 0.5 percent by weight, based upon the weight of the isophthalic acid, of p-toluenesulfonic acid. The process of the present invention is conducted in the absence of a solvent, generates only a small amount of foam, and forms water as the sole, readily removable by-product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.