Enhanced electromechanical actuation in acrylic elastomer foam using barium titanate and Ketjenblack dispersed interpenetrated polymer network

VHB 4910/05 polymeric foam tape manufactured by 3M conglomerate is widely acknowledged as a dielectric elastomer with exceptional electromechanical actuation performance than its counterparts. However, actuation in VHB elastomers is well-known to be enhanced by cross-linkers and plasticizers, the impacts of particulate fillers on their structure, properties, and performance are yet to be recognized. This work addresses the influences of barium titanate (BT) and Ketjenblack (KB) dispersed trimethylolpropane trimethacrylate (TMPTMA) as fillers on the behavior of VHB 4910 elastomer for the planar actuators. The elastomer composites are prepared by swelling and then thermochemical curing of the samples in BT and KB dispersed TMPTMA. The incorporation of fillers in the elastomer matrix is confirmed by comparing optical micrographs, swelling degree, cross-link density, molecular bonds, optical bandgap, and opto-dielectric characteristics. Thus, the dielectric and mechanical behavior and electromechanical actuation performance of the filler-reinforced elastomer are discussed. Improved dielectric constant and specifically reduced elastic modulus are witnessed due to the gelation of TMPTMA leading to a new range of actuation in VHB 4910 elastomer. The areal actuation in elastomer comprising BT, KB and BT-KB particle dispersed TMPTMA is estimated at about 180%, 150% and 165%, respectively. The low electric field requirement is noticed for BT-containing elastomer composite. This work scopes the use of swelling techniques to modify microporous elastomers with particulate fillers towards soft actuators, sensors, and energy generators.

Graphical abstract