writer：Chuansong Yu, Xinkai Li, Xin Yang, Xiaoyan Qiu, Xinxing Zhang,* Zhenming Chen,* and Yanglin Luo
keywords：dynamic covalent bonding, ?exible actuators, gradient structure, MXene, self-healing
source：期刊
Issue time：2024年

Flexible actuators with excellent adaptability and interaction safety have a

wide range of application prospects in many ?elds. However, current ?exible

actuators have problems such as fragility and poor actuating ability. Here,

inspired by the features of nacre structure, a gradient structured ?exible

actuator is proposed with mechanical robustness and self-healing ability. By

introducing dynamic boronic ester bonds at the interface between MXene

nanosheets and epoxy natural rubber matrix, the resulting nanocomposites

with ordered micro-nano structures exhibit excellent tensile strength

(25.03 MPa) and satisfactory repair e?ciency (81.2%). In addition, the

gradient distribution structure of MXene nanosheets endows the actuator

with stable photothermal conversion capability, which can quickly respond to

near-infrared light stimulation. The interlayer dynamic covalent bond

crosslinking enables good response speed after multiple bending and is

capable of functional self-healing after damage. This work introduces gradient

structure and dynamic covalent bonding into ?exible actuators, which

provides a reference for the fabrication of self-healing soft robots, wearable,

and other healable functional materials.