The 3D printing of dielectric elastomer films assisted by electrostatic force

Compared with traditional methods for preparing dielectric elastomer (DE) films, electrohydrodynamic (EHD) 3D printing displays many advantages, notably full automation, computer control and flexible design. It also confers high printing resolution, high preparation efficiency with minimal probability of nozzle clogging. In this article, EHD 3D printing was employed to fabricate silicone rubber (SR) based DE films. In order to increase their dielectric constant, high dielectric copper phthalocyanine (CuPc) particles were added into the SR ink. Optimal printing conditions were determined by analyzing the effects of printing voltage and ink properties on the formation of liquid cone and the printed line width. The SR/CuPc composite film with 3 wt% CuPc particles (SR/CuPc-3) exhibits a high dielectric constant of 5.52, with a large actuated area strain of 23.7% under an electric field of 39.4 V μm⁻¹. Furthermore, under 100 cycles of electric field loading, SR/CuPc-3 demonstrate excellent electromechanical stability, indicating that EHD 3D printing holds a considerable potential for fabricating high-performance DE films in an efficacious manner. (paper)