Effects of Two Scaling Exponents on Swelling-Induced Softening of Elastomers under Equibiaxial and Planar Extensions

Abstract:

We study the effects of two scaling exponents on the mechanical properties of swollen elastomers under equibiaxial and planar extensions. Two scaling exponents are introduced to extend the Flory-Rehner free energy function, and are adjusted based on the previous study. Results show that swelling-induced strain softening is apt to occur under equibiaxial extension compared to uniaxial extension. The additional tensile stress in a lateral direction enables it to occur in relatively poor solvents, and accelerates the onset point. Planar extension shows more complicated responses because the stress in the constrained direction changes dramatically depending on the combination of two scaling exponents and the Flory-Huggins interaction parameter.

• Periodical: Key Engineering Materials (Volume 725)
• Pages: 427-432
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.725.427
• Online since: December 2016
• Authors: Dai Okumura*, Masahiro Mizutani
• Keywords: Constitutive Modeling, Elastomers, Mechanical Properties, Strain Softening, Swelling

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