Multiaxial Deformations of End-linked Poly(dimethylsiloxane) Networks 5. Revisit to Mooney-Rivlin Approach to Strain Energy Density Function

Abstract

We strictly assess the validity of the familiar Mooney-Rivlin approach to the strain energy density function (W) on the basis of the quasi-equilibrium uniaxial and biaxial deformation data of end-linked poly (dimethylsiloxane) networks prepared from the solutions with various precursor concentrations. The constants C1 and C2 in the Mooney equation (W = C 1 (I1 - 3) + C2 (I2 - 3)) are obtained from the intercept and slope of the linear correlation in the Mooney-Rivlin plots for the uniaxial data, respectively. The biaxial stress-strain relations estimated by the Mooney equation are far from the real behavior for all samples. It is clearly demonstrated that-the Mooney-Rivlin approach, which has still been employed due to the simplicity in many studies, is unsuccessful to deduce the form of W.