Polybenzimidazole fiber

Polybenzimidazole or PBI fiber (1983) is a synthetic fiber with an extremely high melting point that also does not ignite. Because of its exceptional thermal and chemical stability, it is often used by fire departments and space agencies.

PBI's Inventor - “Speed”

PBI fiber was invented by [http://www.chemheritage.org/exhibits/ex-aaap-detail.asp?ID=205&Numb=8 Carl Shipp “Speed” Marvel, (1894.Sept.11-1988.Jan.04)] .

During World War II, Marvel worked for the National Defense Research Committee to create synthetic rubber, and the efforts of the group that he spear-headed were crowned by success within one year’s time.

In the latter portion of his career, Marvel became interested in the problem of creating high-temperature stable polymers and his investigations carried out under the sponsorship of the U.S.D.A., the U.S.Army, and finally, the U.S.Air Force bore fruit with the synthesis of Polybenzimidazole that was found to have significant applications to national defense as well as to everyday living.

Production

The Federal Trade Commission definition for PBI fiber is "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."

PBI is prepared by step-growth polymerization from tetra-aminobiphenyl and diphenyl isophthalate spun via a dry spinning process using dimethyl acetamide as the solvent.

First U.S. Commercial PBI Fiber Production: 1983, Celanese Corporation

PBI fiber characteristics

The chemical formula of Poly [2,2’-(m-phenylen)-5,5’ bibenzimidazol] (PBI) is believed to be:( [NH-C=CH-C=CH-CH=C-N=C-] ₂- [C=CH-C=CH-CH=CH-] )_n OR (C₂₀N₄H₁₂)_n of Molar mass 308.33608 ± 0.01764 g/mol.

Chemical Resistance

* abrasion resistant

Physical Properties

* will not ignite or smolder (burn slowly without flame)
* mildew and age resistant
* resistant to sparks and welding spatter

Thermal Properties

* continuous temperature: 540 °C (1,000 °F)
* melting temperature: 760 °C (1,400 °F) under pyrolysis
* retains fiber integrity and suppleness up to 540 °C (1,000 °F)

Major industrial PBI fiber uses

* high-performance protective apparel such as:
** firefighter turnout coats and suits
** astronaut space suits
** high temperature protective gloves
** welders' apparel
** race driver suits
* braided packings
* aircraft wall fabrics

Future Industrial PBI Fiber Uses

ee also

* Textile
* Imidazole

References

[http://www.goodfellow.com/E/Polybenzimidazole.HTML Polybenzimidazole (PBI) - Material Information]
[http://www.hos-tec.com/cms/index.php?option=com_content&task=view&id=13&Itemid=16 Summary of Polybenzimidazole]

External links