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The double‐network (DN) concept, initially applied to hydrogels, has been adapted to elastomers, resulting in materials that combine exceptional toughness with tunable elasticity. This article delves into the constitutive and fracture behaviors of DN elastomers, elucidating the pivotal role of prestretch and composition in tailoring their properties. An incompressible hyperelastic model is employed to predict the stress–strain behavior and energy release rate of a DN elastomer, focusing on how the interactions between the two networks influence its overall material properties. The influence of prestretch and composition on increasing the stiffness and energy release rate of a DN elastomer is analytically determined. The analytical predictions are validated experimentally through comprehensive mechanical and fracture testing using a DN elastomer fabricated by a two‐step crosslinking process to decouple the prestretch and composition. The results show that manipulating these processing parameters can finely tune the mechanical responses of DN elastomers, optimizing them for specific applications. The findings provide new insights into the mechanics of DN elastomers.
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On the two-potential constitutive modeling of dielectric elastomers
This work lays out the two-potential framework for the constitutive modeling of dielectric elastomers. After its general presentation, where the constraints imposed by even electromechanical coupling, material frame indifference, material symmetry, and entropy imbalance are all spelled out, the framework is utilized to put forth a specific constitutive model for the prominent class of isotropic incompressible dielectric elastomers. The model accounts for the non-Gaussian elasticity and electrostriction typical of such materials, as well as for their deformation-enhanced shear thinning due to viscous dissipation and their time-dependent polarization due to electric dissipation. The key theoretical and practical features of the model are discussed, with special emphasis on its specialization in the limit of small deformations and moderate electric fields. The last part of this paper is devoted to the deployment of the model to fully describe the electromechanical behavior of a commercially significant dielectric elastomer, namely, the acrylate elastomer VHB 4910 from 3M.
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- PAR ID:
- 10191047
- Date Published:
- Journal Name:
- Meccanica
- ISSN:
- 0025-6455
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s11012-020-01179-1
