Tunable Electroelastic Waves in Soft Dielectric Elastomer Phononic Crystals: Exploring the Effect of Polymer Chain Network Architecture

The polymer chain network within the dielectric elastomers (DEs) contains numerous entanglements, crosslinks and finite extensibility, all of which play a substantial role in the nonlinear finite deformation behavior of the DE-based phononic crystals. In this study, a theoretical model is proposed to investigate the intricate interplay between internal polymer chain entanglements, crosslinks and finite extensibility, and their influence on the tunable band gap properties of soft dielectric elastomer phononic crystals. To capture the inherent characteristics of the polymer chain network, a physics-based nonaffine material model is employed. By incorporating nonlinear electro-elasticity theory and the linearized incremental theory, the equations governing the voltage-induced finite deformation and superimposed incremental anti-plane shear waves are formulated. Employing the finite element method and Bloch’s theorem, the band structure of an infinite periodic DE phononic crystal is extracted. The numerical results reveal that under higher electric fields, the intrinsic properties of the polymer network significantly impact the band gap characteristics of DE phononic crystals. The outcomes of the numerical simulations and the insights derived from this study offer valuable guidance for the design and manufacturing of soft electro-statically tunable phononic structures.