Novel DEA materials by chemical grafting of silicone networks on molecular level

Dielectric elastomer actuators (DEAs) can be optimized by modifying the dielectric or mechanical properties of the electroactive polymer. In this work both properties were improved simultaneously by a simple process, the one-step film formation. The silicone elastomer network contains polydimethylsiloxane (PDMS) chains, as well as crosslinker and grafted molecular dipoles in varying amounts. This leads to films, which are homogenous down to the molecular level. Films with higher permittivity and reduced stiffness were obtained. As matrix two PDMS-materials with different molar masses, leading to other network chain lengths, were compared. This directly influences the network density and thus the mechanical properties. A higher electrical field response for long chain matrix materials was found. The actuation sensitivities for both materials were enhanced by 6.3 and 4.6 times for the short and long chain matrix material, respectively.