Low-voltage-driven sustainable weightlifting actuator based on polymer-nanotube composite

A low-voltage-induced sustainable composite actuator is fabricated by repeated grinding of multiwalled carbon nanotubes into a polydimethylsiloxane matrix. The composite exhibits a reversible elongation motion with the applied dc voltage, and a visible strain of nearly 7.5% can be obtained under the 30 V voltage. An electrothermal effect introduced by the carbon nanotube networks in the composite and the induced thermal expansion of the composite is responsible for the electrical actuation behavior. Moreover, the actuated displacement can be controlled by tuning the input electrical power and sustained for a long time period under electrical stimulus without performance degradation. This is due to the dynamic thermal equilibrium of the thermal generation and loss reached in the composite. A coin that is 40 times heavier than the weight of the actuator can be easily lifted upward under the electrical actuation, which demonstrates the excellent weightlifting property. KGaA, Weinheim.