An experimental investigation on the degradation effect of ozone on hyperelastic behavior of an NR/BR blend

Effect of nanoclay content and matrix composition on properties and stress–strain behavior of NR/EPDM nanocomposites

“…This model represents the underlying molecular structure of the rubbers to simulate the non-Gaussian behavior of individual chains in the network. 21,23 The form of the Arruda-Boyce strain energy potential is as follows:…”

“…It should be noted that the full incompressibility is assumed, meaning all hyperelastic equations only contain the deviatoric part and the volumetric part is neglected. [21][22][23] Ogden. Ogden proposed the strain density function can be described directly in terms of principal stretch ratios as follows:…”

“…where l i and a i are material constants. [21][22][23] In this work, it is assumed that N ¼ 3. The initial shear modulus of the rubber in this model is computed by the following:…”

“…(13) in which m ¼ 3. 22,23 W ¼ C 10 ðI 1 À 3Þ þ C 20 ðI 1 À 3Þ 2 þ C 30 ðI 1 À 3Þ 3 (15) Fitting Procedure At the first step, test data were used to characterize the material parameters of the hyperelastic models. As we know, the first deviatoric strain invariant defined as follows:…”

An experimental study of the effect of CNTs on the mechanical properties of CNTs/NR/EPDM nanocomposite

“…NR/EPDM blends are nearly incompressible and thus their mechanical behavior can be described by hyperelastic models whose strain energy density is correlated to the strain invariants. Ghoreishy et al have investigated the ozone degradation effect on hyperelastic behavior of the NR and butadiene rubber (BR) blends. They found that the parameters of nonlinear mechanistic models such as Arruda–Boyce and Van der Waals can be related to chain scission which takes place during ozone attack on the polymer backbone in rubber compounds.…”