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Thermoreversible Gelation of Polybenzimidazole in Phosphoric Acid

โœ Scribed by Arindam Sannigrahi; Dhamodaran Arunbabu; Tushar Jana

Publisher
John Wiley and Sons
Year
2006
Tongue
English
Weight
194 KB
Volume
27
Category
Article
ISSN
1022-1336

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โœฆ Synopsis

Abstract

Summary: We report a study of thermoreversible gelation of polybenzimidazole (PBI) in phosphoric acid (PA). The PBI gel in PA exhibits fibrillar network morphology and reversible first order phase transition. The gelation rate is measured by the tube tilting method and found to depend both upon gelation concentration and gelation temperature. The UVโ€vis study demonstrates that the gelation process is a twoโ€step process: conformational transformation and aggregation which produces crystallites for gel formation. The WAXS study supports the presence of crystallites in the gel. The PA doping level of the membrane increases significantly because of gelation.

Thermoreversible gelation of polybenzimidazole in phosphoric acid and the membrane produced from the gel.

magnified imageThermoreversible gelation of polybenzimidazole in phosphoric acid and the membrane produced from the gel.

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