Electrically charged cellular polymers are known to display pseudo-piezoelectric effects that endow them with interesting mechano-electrical characteristics. When a film of such a polymer is compressed, charge is generated across its thickness, and conversely, applying an oscillatory or static potential elicits mechanical motions. This dual sensor-actuator behaviour can be embedded in one material and presents distinct advantages of functional integration. A novel electroactive foam is presented here that embeds such a sensor-actuator function. The foam has a sensitivity constant (d33) of 330 pC N−1. Interestingly, the resonant behaviour of the cellular film can be altered by variation in the DC offset across the material. Such adaptive capacity could be of great advantage for tuning polymer-based mechanical devices to be either efficient sound radiators and mechanical actuators, or sensitive and coherent sensors. Possible applications in microfluidics are also discussed.
- soft matter
- condensed matter
- nanoscale science
- low-D systems
Windmill, J. F. C., Zorab, A., Bedwell, D., & Robert, D. (2008). Nanomechanical and electrical characterization of a new cellular electret sensor–actuator. Nanotechnology, 19(3), . https://doi.org/10.1088/0957-4484/19/03/035506