Supplier Data - Polybenzimidazole ( PBI ) ( Goodfellow )

An infusible, Polybenzimidazole (PBI) is a black high performance polymer with a wholly aromatic molecule of high thermal stability. Semi-fabricated items are made, normally by the polymer manufacturer, by powder sintering processes.

Polybenzimidazole (PBI) has excellent high temperature properties - probably on balance the best of any commercially available polymer - and is very expensive. It is strong, stiff, very hard, has a particularly high strength in and recovery from compression and a CTE similar to that of aluminium.

Polybenzimidazole (PBI)has good chemical resistance resisting many harsh chemical environments better than many other high performance polymers, but is attacked by polar aprotic solvents and, at elevated temperatures, by strong aqueous acids and (to a lesser extent) alkalis.

Despite absorbing (slowly) a high percentage of water at saturation, Polybenzimidazole (PBI)is stable to hydrolysis and resists high pressure steam.

Key Properties

The key properties of Polybenzimidazole ( PBI ) are tabulated below.

Table 1. Key properties

Chemical Resistance
Acids - concentrated Fair
Acids – dilute Good
Alcohols Very Good
Alkalis Good/Fair
Aromatic hydrocarbons Very Good
Greases and Oils Very Good
Ketones Very Good
Electrical Properties
Dielectric constant @ 1 MHz 3.2
Dielectric strength ( ) 21
Volume resistivity ( ) 8x1014
Mechanical Properties
Coefficient of friction 0.19 - 0.27
Compressive modulus ( GPa ) 6.2
Compressive strength ( MPa ) 400
Elongation at break ( % ) 3
Hardness – Rockwell K115
Izod impact strength ( J.m-1 ) 590 unnotched
Poisson’s ratio 0.34
Tensile modulus ( GPa ) 5.9
Tensile strength ( MPa ) 160
Physical Properties
Density ( ) 1.3
Flammability Does not burn
Limiting oxygen index ( % ) 58
Radiation resistance – Alpha Good
Water absorption - over 24 hours ( % ) 0.4
Thermal Properties
Coefficient of thermal expansion ( x10-6 K-1 ) 23
Heat-deflection temperature - 0.45 MPa ( °C ) 435
Thermal conductivity @ 23 °C ( W.m-1.K-1 ) 0.41
Upper working temperature (°C ) 260 - 400

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Source: Goodfellow.

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  1. Ratikanta Nayak Ratikanta Nayak India says:

    I need to Purchase PBI polymer for my R&D purpose. To whom should I contact

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