Effects of Stretching on Nafion Morphology and Properties

Abstract

Abstract:

²H NMR and PFG NMR were performed on uniaxially stretched Nafion membrane to evaluate the deformation effects on its morphology and properties. We
conducted a systematic study on Nafion over draw ratio range from 1 to 7. Uniaxial deformation was found to lead a strong alignment of the hydrophilic channel, and enhance the water mobility along the draw direction before reaching the max orientation (L<5). These effects could be used for improving the PEMs´ properties. The deformation after the max orientation (L≥5) led to a decrease of mobility of the water molecules. This stretching effect also led to anisotropic swelling of the membranes in solvent as the channels align along the draw direction. The absorption and mobility of methanol increased as the draw ratio, hindering its application in DMFC.

Key words: NMR, uniaxial stretch, morphology-property-relationship, water, methanol

CLC Number:

O482.53

JIANG Xiao-feng1,2，WANG Li-ying1，FENG Ji-wen1*.

Effects of Stretching on Nafion Morphology and Properties

[J]. Chinese Journal of Magnetic Resonance.

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