Document Type: Research Paper

Authors

1 University of South Africa Department of Mechanical and Industrial Engineering

2 University of South Africa

Abstract

This paper presents the results of mechanical strength of wet and dry zirconia/ Nafion® nano-composite membrane. The tensile tests were conducted to determine elastic modulus and stiffness of dry and wet pristine Nafion® membrane and modified Nafion® membrane. The composite membranes were prepared by recast method of different synthesized zirconium oxide with the zirconia content of 10% by weight. The uniaxial mechanical properties of nano-composite membranes and recast Nafion® membrane were captured using a CellScale UStretch uniaxial testing system. The length, width, and thickness of samples were measured using a Vernier caliper and recorded prior to testing. It was found that elastic modulus of the wet Nafion recast is 62.06 %, 35.26 %, 30.79 % and 35.26 % higher than that of Nafion®/ Zr-100, Nafion/® Zr-80, Nafion®/Zr-50, and Nafion®/Zr-0, respectively. The elastic modulus of dry Nafion recast, Nafion®/Zr-100, Nafion®/Zr-80, Nafion®/Zr-50, and Nafion/Zr-0 membranes are 46.29 %, 83.31 %, 64.81 %, 59.84 %, and 78.36 % higher than those of wet Nafion® recast, Nafion®/Zr-100, Nafion®/Zr-80, Nafion®/Zr-50, and Nafion®/Zr-0 membranes, respectively. Furthermore, the results showed that when the water content increases in the nano-composite membranes the mechanical strength also decreases.

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