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Creasing to cratering instability in polymers under ultrahigh electric fields
Qiming Wang1, Lin Zhang, Xuanhe Zhao
1Soft Active Materials Laboratory, Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, USA.
Physical Review Letters
|April 8, 2011
Summary
A new electrocreasing instability in polymers forms creases and craters under high electric fields. This phenomenon
Area of Science:
- Materials Science
- Polymer Physics
- Electromechanics
Background:
- Elastic polymers are susceptible to various instabilities when subjected to external stimuli.
- Understanding electromechanical instabilities is crucial for designing advanced polymer-based devices.
Purpose of the Study:
- To investigate and characterize a novel instability in substrate-bonded elastic polymers under ultrahigh electric fields.
- To develop a theoretical model for predicting the critical electric field of this instability.
Main Methods:
- Experimental application of ultrahigh electric fields to substrate-bonded elastic polymers.
- Observation and analysis of surface morphological changes (creasing and crater formation).
- Development of a theoretical model based on potential energy comparison.
- Linear stability analysis for comparison.
Main Results:
- A critical electric field triggers local folding, forming creases on the polymer surface.
- Increased electric fields lead to larger creases and crater formation.
- The critical field scales with the square root of the polymer's modulus.
- Linear stability analysis overestimates the critical field.
Conclusions:
- A new electrocreasing instability in elastic polymers has been identified and characterized.
- A theoretical model accurately predicts the critical electric field, outperforming linear stability analysis.
- The findings provide insights into electromechanical behavior of polymers and potential applications.
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