Electrical powerless, thermal and optical responsive polymer-based actuator

This study demonstrates thermal and optical responsive actuator operated by skin temperature and sunlight without using electrical power supply. Different types of thermal and optical responsive actuators have been reported to date. However, actuator stimulated by both skin temperature and sunlight has yet to be demonstrated, although these are a high potential as the next class of power sources for devices. To realize an actuation using these stimuli, we propose to use a mixture of poly(N-isopropylacrylamide) (pNIPAM) as a thermal actuation material and carbon nanotubes (CNTs) as a light absorber to convert into heat on a polyethylene terephthalate (PET) substrate. By considering a packaging technique of the pNIPAM film, a human body temperature-and the sunlight-stimulated actuator is successfully demonstrated in air ambient.