Electrically responsive materials based on dibutyl phathalate plasticized poly(lactic acid) and spherical fullerene

Carbon-based electromechanical actuators, capable of reversible shape changes in response to electrical stimuli, have found many potential utilizations such as robotic artificial muscles, micro-pumps, and sensitive switches. In this work, electroactive materials based on the dibutyl phathalate (DBP) plasticized poly(lactic acid) (PLA) and fullerene (C₆₀) were produced by a simple solvent casting method. The PLA composites exhibited fast and reversible responses under electrical stimulus. The highest storage modulus response was obtained from the 1.0%v/v C₆₀/PLA/DBP at 23.51 × 10⁵ Pa under the 1.5 kV mm⁻¹ electric field. In the bending experiment, the PLA composites bended towards the anode from the attractive force between the negative charges of the induced dipole moments namely the carbonyl groups in PLA and DBP and the π-conjugated electrons of C₆₀ and the positive electrode. The C₆₀/PLA/DBP composite with a small C₆₀ content (0.1%v/v) yielded the maximum bending distance of about 6.0 mm within 10 s and the highest dielectrophoresis force of 1.01 mN at 550 V mm⁻¹. Thus, the electrically responsive PLA composites fabricated here with the short response time and high bending deformation are demonstrated here to be promising biobased materials towards actuator applications.