Stretchable High Response Piezoelectric Elastomers Based on Polable Polynorbornene Fillers in a Polydimethylsiloxane Matrix

摘要

To advance the field of piezoelectrics, it is desirable to find materials thatcombine high piezoelectricity with high elasticity. Applications such as selfsensors,stretchable electronics, soft robots, and energy harvesting wouldbenefit tremendously. However, this is not an easy task neither for materialsbased on ceramics nor for those based on polymers. While ceramics canshow strong piezoelectric effects, their mechanical response tends to beweak. Polymers instead are elastic but only few have sizeable piezoelectriceffects. Additionally, they cannot maintain the polarization permanently asneeded for piezoelectrics. Here, an all-organic piezoelectric elastomer is synthesizedby blending high glass transition temperature (T_g = 104 ℃) polar polynorbornenenanoparticles (NPs) with a high relaxation strength (Δε′ = 22.4)into a chemically cross-linked polydimethylsiloxane matrix. After processingthe blends into thin films by doctor blading, they are poled by corona dischargeat elevated temperatures. Fifteen days after poling, the materials showa stable and reversible piezoelectric response d_(31) = 37 pC N~(?1). This, to thebest of the authors’ knowledge, not only is the highest d_(31) value reported, butthe response is three times that of the well-known polyvinylidene difluoride.