  We propose a model to analyze the insurgence of pull-in and wrinkling
failures in electroactive thin films. We take in consideration both cases of
voltage and charge control, and study the role of prestretch and size of
activated regions, which are essential in the analysis of realistic
applications of EAPs. Based on simple geometrical and material assumptions we
deduce an explicit analytical description of these phenomena, allowing a clear
physical interpretation. Despite our simplifying assumptions, the comparison
with experiments shows a satisfying qualitative and, interestingly,
quantitative agreement. In particular our model shows, in accordance with
experiments, the existence of different optimal prestretch values, depending on
the choice of the actuating parameter of the EAP.
