Deformation-controlled and ultrasensitive polyimide/paraffin wax/carbon nanotube composite NIR-responsive photoactuators

Light-responsive actuators have become increasingly popular in various fields such as soft robotics, biomedical devices, and photosensitive electronic devices due to their remote wireless operation and high deformation efficiency. However, controlling actuator deformation efficiency and modes remains a significant challenge. Herein, a new 3D printed polyimide (PI)/paraffin wax (PW)/carbon nanotube (CNT) NIR-responsive photoactuators with controlled deformation mode and ultrasensitive light response has been proposed. The process involves printing a CNT slurry according to a predetermined path, followed by lamination with PW and PI film to create PI/PW/CNT (PPC) NIR responsive photoactuators. Then, the effects of the CNTs pattern (line width and line spacing) on the deformation efficiency were studied and optimized. Upon optimization, the deformation time can be reduced to 3 s and the deformation angle can be raised to 70 °. Moreover, the PPC actuator is highly sensitive to temperature and can be deformed within a temperature difference of about 2-3 °C. Finally, various PPC photoactuators including Flower-shape and soft mechanical hand have been prepared to present the different deformation forms. Overall, this work presents a new approach to researching multifunctional NIR-responsive photoactuators with adjustable deformation structures.