Direct Current Electric Field Induced Gradient Hydrogel Actuators with Rapid Thermo-Responsive Performance as Soft Manipulators
Abstruct: Polymeric hydrogels as biomimetic soft actuators have attracted great attentions, but the design of rapid responsive hydrogel actuators via a facile and sustainable pathway still faces great challenges. Herein, rapid thermo-responsive hydrogel actuators with high performances were fabricated by utilizing direct current (DC) electric field to induce the gradient distribution of renewable tunicate cellulose nanocrystals (TCNCs) in the poly(N-isopropylacrylamide) (PNIPAM) matrix. The spatial distribution of TCNCs that acted as both nanofillers and multifunctional cross-linkers in PNIPAM was adequately demonstrated by 3D Raman technology, which played a dominant role in the fast bending (4.8 °/s) and recovery velocity (1.4 °/s) of the corresponding hydrogel actuators. Moreover, the PNIPAM/TCNC hydrogels with excellent durability and stability could be used as potential temperature-controlled manipulators for long-term capture and transportation of targeted objects, even in harsh environment.