(Electro)mechanical behavior of selectively solvated diblock/triblock copolymer blends

Thermoplastic elastomeric triblock copolymers swollen with a midblock-selective solvent form a highly elastic physical network that can exhibit remarkable electromechanical properties (high actuation strains and electromechanical efficiency with low hysteresis upon cycling) as dielectric elastomers. One unexplored means of controllably altering the midblock network and the corresponding (electro)mechanical properties at constant copolymer concentration is to substitute non-network-forming diblock for triblock copolymer molecules. In this study, we demonstrate that the incorporation of composition-matched diblock molecules into selectively solvated triblock systems results in softer materials that are less physically crosslinked and thus capable of undergoing electroactuation at reduced electric fields.