Papers by Keyword: Nonaffine Model

Abstract: The water channels inside the Nafion membrane are considered as the elastic particles and the effect of the elastic modulus of the particles on the deformation behavior of the membrane is discussed with a particle-contained composite model, which is constituted based on the homogenization method. The results show that the deformation resistance of the membrane is quite dependent on the elastic modulus of the particles, whereas the strain softening behavior after the yielding of the membrane is almost derived from the onset and the propagation of the localized shear band in the matrix, which also leads to the dramatic disappearance of the entanglement points in the molecular chain network of the matrix.

Abstract: To clarify the essential deformation characteristics of silica-filled rubber, we construct the finite element homogenization models of silica-filled rubber with newly proposed nonaffine molecular chain network model of rubber. These models can reflect the generation of complicated inter-fillers connecting phases where the characteristics of rubber are intricately changed depending on the volume fraction of silica coupling agent and relative size of particles and their location. The results obtained clarified the essential physical enhancement mechanisms of deformation resistance and hysteresis loss for rubber filled with silica with different distribution patterns under diffrent rate of deformation. The volume fraction of coupling agent essentially affects the deformation behavior of silica filled rubber which suggests the high controlability of the material characteristics of silica filled rubber as compared with carbon black filled rubber.

Abstract: The constitutive equation of rubber is derived by employing a nonaffine molecular chain network model for an elastic deformation behavior and the reptation theory for a viscoelastic deformation behavior. The results reveal the roles of the individual springs and dashpot, and the strain rate dependence of materials and disentanglement of molecular chains in the monotonic and cyclic deformation behaviors, particularly softening and hysteresis loss, that is, the Mullins effect, occurring in stress-stretch curves under cyclic deformation processes.