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The coupled hyperelastic strain-energy function for this material is given by [36], $$\begin{equation} \Psi\left(I_{1},I_{2},J\right)=\frac{1}{2}c\left(e^{Q}-1\right)\,,\label{eq430} \end{equation}$$ where $I_{1}$ and $I_{2}$ are the first and second invariants of the right Cauchy-Green tensor and $J$ the jacobian of the deformation. Furthermore, $$\begin{equation} \begin{aligned}Q & =\frac{\beta}{\lambda+2\mu}\left[\left(2\mu-\lambda\right)\left(I_{1}-3\right)+\lambda\left(I_{2}-3\right)-\left(\lambda+2\mu\right)\ln J^{2}\right]\,,\\ c & =\frac{\lambda+2\mu}{2\beta}\,, \end{aligned} \label{eq431} \end{equation}$$ and $\lambda$ and $\mu$ are the Lamé parameters. The corresponding Cauchy stress tensor is $$\begin{equation} \boldsymbol{\sigma}=\frac{1}{2J}e^{Q}\left(\left[2\mu+\lambda\left(I_{1}-1\right)\right]\mathbf{b}-\lambda\mathbf{b}^{2}-\left(\lambda+2\mu\right)\mathbf{I}\right)\,,\label{eq432} \end{equation}$$ and the spatial elasticity tensor is $$\begin{equation} \boldsymbol{\mathcal{C}}=\frac{4\beta}{\lambda+2\mu}Je^{-Q}\boldsymbol{\sigma}\otimes\boldsymbol{\sigma}+J^{-1}e^{Q}\left[\lambda\left(\mathbf{b}\otimes\mathbf{b}-\mathbf{b}\,\overline{\underline{\otimes}}\,\mathbf{b}\right)+\left(\lambda+2\mu\right)\mathbf{I}\,\overline{\underline{\otimes}}\,\mathbf{I}\right]\,.\label{eq433} \end{equation}$$