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Effect of ball milling on electrochemical properties of PVdF-HFP porous membranes applied for DMFCs / G. Gnana kumar in Industrial & engineering chemistry research, Vol. 49 N° 3 (Fevrier 2010)

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 3 (Fevrier 2010) . - pp. 1281–1288 Titre : Effect of ball milling on electrochemical properties of PVdF-HFP porous membranes applied for DMFCs Type de document : texte imprimé Auteurs : G. Gnana kumar, Auteur ; Chang Su So, Auteur ; A. R. Kim, Auteur Année de publication : 2010 Article en page(s) : pp. 1281–1288 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Effect--Ball  Milling--Electrochemical--PVdF-HFP--Porous--Membranes--Applied--DMFCs Résumé : Poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) porous polymer electrolyte membranes were prepared by the solvent−nonsolvent evaporation technique. The particle size and molecular weight of the polymer were greatly varied with the ball-milling technique, and the electrochemical properties of the polymer electrolyte membranes were examined as functions of these variations. The high hydrophobic nature of the host polymer is responsible for the high-temperature application and low methanol permeation. A hydrophilic nature was imparted to the fabricated porous membranes through activation with silica sulfuric acid liquid electrolyte. A decrease in the molecular weight effectively reduces the viscosity and is responsible for high ion migration. In addition, a decrease in the particle size lead to an effective acidification, so that the acidified polymer could effectively promote the ionic conductivity further. A much lower fuel permeation associated with the high ionic conductivity of the ball-milled membranes facilitates the performance of direct methanol fuel cells and supports their potential application therein. ISSN : 0888-5885 [article] Effect of ball milling on electrochemical properties of PVdF-HFP porous membranes applied for DMFCs [texte imprimé] / G. Gnana kumar, Auteur ; Chang Su So, Auteur ; A. R. Kim, Auteur . - 2010 . - pp. 1281–1288. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 3 (Fevrier 2010) . - pp. 1281–1288 Mots-clés : Effect--Ball  Milling--Electrochemical--PVdF-HFP--Porous--Membranes--Applied--DMFCs Résumé : Poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) porous polymer electrolyte membranes were prepared by the solvent−nonsolvent evaporation technique. The particle size and molecular weight of the polymer were greatly varied with the ball-milling technique, and the electrochemical properties of the polymer electrolyte membranes were examined as functions of these variations. The high hydrophobic nature of the host polymer is responsible for the high-temperature application and low methanol permeation. A hydrophilic nature was imparted to the fabricated porous membranes through activation with silica sulfuric acid liquid electrolyte. A decrease in the molecular weight effectively reduces the viscosity and is responsible for high ion migration. In addition, a decrease in the particle size lead to an effective acidification, so that the acidified polymer could effectively promote the ionic conductivity further. A much lower fuel permeation associated with the high ionic conductivity of the ball-milled membranes facilitates the performance of direct methanol fuel cells and supports their potential application therein. ISSN : 0888-5885