Session: Research Posters

Paper Number: 112584

112584 - On the Electromechanical Instability of Polar Elastomers 

Based on a continuum theory that accounts for the underlying molecular physics of polar elastomers (PEs), a typical boundary value problem (BVP) is developed to analyze the electro-mechanical instability (EMI) of PEs with randomly distributed dielectric particles.

Polar elastomers (PEs) are recently developed as new electro-active materials with enhanced dielectric constants and high deformability. These materials are synthesized by chemically bonding polar groups into polymer chains. The synthesized material could be used in the design of various engineering components such as, soft actuators, compliant sensors, energy harvesters, flexible robots, and Braille displays.

However, the applications of electro-active elastomers are significantly limited by the electro-mechanical instability (EMI) when subjected to a critical voltage, beyond which, elastomers collapse and result in undesirable response. PEs are composite materials with spatially varying dielectric properties. The PE material with spatially varying dielectric properties from the based material are also known as dielectric imperfections (DIs).

To prevent the uncertainty brought by DIs in the applications of PEs, DIs are usually controlled in practice by well-distributing polar groups with small sizes in the based material to the extent that PEs can be considered homogeneous. To safely apply PEs in a design, it is desirable to find the critical voltage at which EMI occurs. In this paper, a statistics inspired multi-scale computational approach is proposed, to quantitatively determine the critical voltage, using well-established physics-based boundary value problem (BVP). In addition, through numerous numerical simulations, the effects of various parameters that influence the critical voltage are identified and discussed. The results are concisely organized and presented in 3D phase diagrams.

The remainder of this work is organized as follows. Section 2 introduces the mathematical modeling and numerical aspects within a continuum framework. In Section 3, the typical BVP for EMI analysis is introduced and analytical solution is provided. In Section 4, extensive numerical simulation results are presented and discussed about the EMI of PEs with DIs. This is followed by concluding remarks in Section 5.

A mathematical model to analyze elastic deformation of PEs when subjected to a mechanical or an electrical stimulus is developed and through extensive numerical simulations, the effects of various parameters such as particle volume fraction, particle size and enhancement factor related to polar groups on the critical voltage leading to EMI of PEs are investigated. The results are presented in 3D phase diagrams, which may better help researchers to understand EMI of PEs and guide them in synthesis, design, and application of PEs in the fields of chemistry, physics, bioengineering, etc.

 

Presenting Author: Hamid Nayeb-Hashemi Northeastern University

Presenting Author Biography: Professor Nayeb-Hashemi is an an expert in the area of Biomechanics and mechanics. He is a
Fellow, of American Society of Mechanical Engineers.

Authors:

masoud olia Wentworth Institute of Technology
Hamid Nayeb-Hashemi Northeastern University
Yanhui Jiang Nanjing University of Science and Technology,
Yan Su Nanjing University of Science and Technology