PBI fibre (polybenzimidazole)
Also known as: polybenzimidazole, PBI, PBI Gold
High-performance synthetic fibre that will not melt below 500 °C — the core of every professional firefighter turnout shell.
Description
Polybenzimidazole (PBI) is a high-performance fibre developed in 1961 by Carl Marvel with exceptional thermal and chemical stability. It does not melt or drip, does not self-ignite in normal air (limiting oxygen index around 41 %) and retains its integrity well above 500 °C.
Commercially available since the 1980s, PBI is used mainly as a blend with para-aramid (“PBI Gold” with Kevlar) for the outer shell of firefighter turnout gear, racing suits, military protective clothing and aircraft seat covers. Its heat protection is intrinsic to the molecular structure and does not degrade with laundering or ageing.
- LOI ~41 % — self-extinguishing, non-dripping
- Dimensionally stable above 500 °C, chemically almost inert
- Most often blended with para-aramid (Kevlar/Twaron)
- Primary markets: turnout gear, motorsport, military, aviation
Properties
| Fibre type | Aromatic high-performance synthetic fibre |
|---|---|
| LOI | ~41 % — non-flammable in air |
| Temperature | Stable above 500 °C, no melting |
| Blend partner | Usually para-aramid (Kevlar, Twaron) |
| Application | Firefighter turnout gear, motorsport, military, aviation |
Related product categories
Sources & references
2- Wikipedia: Polybenzimidazole fiber Wikipedia — Freie Enzyklopädie https://en.wikipedia.org/wiki/Polybenzimidazole_fiber
- NASA Spinoff: PBI Polymer Fabric spinoff.nasa.gov https://spinoff.nasa.gov/Spinoff2008/ps_3.html
