Printable dielectric elastomers of high electromechanical properties based on SEBS ink incorporated with polyphenols modified dielectric particles

In this work, a recently developed 3D additive processing technology termed electrohydrodynamic (EHD) printing was employed to fabricate dielectric elastomer (DE) films by using styrene-ethylene-butylene-styrene (SEBS) inks with the addition of high dielectric titanium dioxide (TiO₂) nanoparticles. In order to improve the dispersibility of TiO₂ in the SEBS matrix, extracted walnut polyphenols were utilized for surface modification of TiO₂ nanoparticles labelled wp-TiO₂. The effect of the applied voltage on the ink jet morphology of the obtained SEBS based inks during EHD printing was analyzed. The prepared films had precision patterned shapes and their morphology was studied. It revealed that the dispersibility of TiO₂ nanoparticles in the SEBS matrix and their compatibility were greatly improved using this procedure. Furthermore, the printed DE films were found to have excellent mechanical, dielectric and electromechanical properties. For the range of DEs fabricated, the SEBS/10%wp-TiO₂ composite exhibited the maximum actuated area strain of 21.5% at an electric field of about 34.0 V/μm without degradation of other properties.