A Dielectric Elastomer Actuator That Can Self-Heal Integrally

Dielectric actuators are prone to be worn or partially damaged when operating at high electric fields. The introduction of self-healing features into dielectric actuators is favorable for extending its life span and security. Although many attempts have been made to produce self-healing dielectric actuators, most of them focus on the healing of either the electrodes or the dielectric layers. A dielectric actuator that exhibits integral self-healing is still unprecedented. Meanwhile, realizing integral self-healing in dielectric actuator is highly challenging because both the electrode and the dielectric layer need to be healed while the interface between the electrode and the dielectric layer should remain unaffected during the healing process. In this paper, we synthesized self-healing polydimethylsiloxane (PDMS) polymers containing different amounts of polyaniline (PANI) (denoted as PDMS–PANIn, where n represents the weight percentage of PANI) as the dielectric layer and electrode, respectively. PDMS–PANI2.5 polymer exhibits good dielectric properties (ε = 11.11 at 50 Hz) and was used as the dielectric layer, while PDMS–PANI20 polymer having a high conductivity of 4.5 × 10–5 S/cm was used as the electrode. As both of them have excellent self-healing ability and are compatible and diffusible to each other, the entire actuator device can still cause actuated strain after cutting and healing at room temperature for 48 h. Our strategy for realizing integral self-healing of actuator is also applicable to other electronic devices.