POLYBENZIMIDAZOLE
First U.S. Commercial PBI Fiber Production: 1983, Celanese Corporation
Current U.S. PBI Fiber Producers: PBI Performance Products
Federal Trade Commission Definition for PBI Fiber: A manufactured fiber in which the fiber forming substance is a long-chain aromatic polymer having recurring imidazole groups as an integral part of the polymer chain. (Complete FTC Fiber Rules here.)
Basic Principles of PBI Fiber Production — PBI is prepared from tetra-aminobiphenyl and diphenyl isophthalate spun via a dry spinning process using dimethyl acetamide as the solvent.
PBI Fiber Characteristics
- No melting point
- Will not ignite
- Retains fiber integrity and suppleness upon flame exposure
- High char yield
- Dyeable to dark shades with basic dyes following caustic pretreatment
- Mildew and age resistant
- Abrasion resistant
Major PBI Fiber Uses — PBI is suitable for high-performance protective apparel such as firemen’s turnout coats and astronaut space suits and in applications where fire resistance is important.