Nanocellulose-mediated bilayer hydrogel actuators with thermo-responsive, shape memory and self-sensing performances

Yuanyuan Ma; Ya Lu; Yiying Yue; Shuijian He; Shaohua Jiang; Changtong Mei; Xinwu Xu; Qinglin Wu; Huining Xiao; Jingquan Han

doi:10.1016/j.carbpol.2024.122067

Nanocellulose-mediated bilayer hydrogel actuators with thermo-responsive, shape memory and self-sensing performances

Carbohydr Polym. 2024 Jul 1:335:122067. doi: 10.1016/j.carbpol.2024.122067. Epub 2024 Mar 21.

Authors

Yuanyuan Ma¹, Ya Lu¹, Yiying Yue², Shuijian He¹, Shaohua Jiang¹, Changtong Mei³, Xinwu Xu³, Qinglin Wu⁴, Huining Xiao⁵, Jingquan Han⁶

Affiliations

¹ Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, Joint International Research Lab of Lignocellulosic Functional Materials, College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China.
² College of Biology and Environment, Nanjing Forestry University, Nanjing 210037, China. Electronic address: yue@njfu.edu.cn.
³ College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China.
⁴ School of Renewable Natural Resources, Louisiana State University, Baton Rouge, LA 70803, United States.
⁵ Department of Chemical Engineering, University of New Brunswick, 15 Dineen Drive, Fredericton, NB E3B 5A3, Canada.
⁶ Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, Joint International Research Lab of Lignocellulosic Functional Materials, College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China. Electronic address: hjq@njfu.edu.cn.

PMID: 38616090
DOI: 10.1016/j.carbpol.2024.122067

Abstract

Inspired by creatures, abundant stimulus-responsive hydrogel actuators with diverse functionalities have been manufactured for applications in soft robotics. However, constructing a shape memory and self-sensing bilayer hydrogel actuator with high mechanical strength and strong interfacial bonding still remains a challenge. Herein, a novel bilayer hydrogel with a stimulus-responsive TEMPO-oxidized cellulose nanofibers/poly(N-isopropylacrylamide) (TOCN/PNIPAM) layer and a non-responsive TOCN/polyacrylamide (TOCN/PAM) layer is proposed as a thermosensitive actuator. TOCNs as a nano-reinforced phase provide a high mechanical strength and endow the hydrogel actuator with a strong interfacial bonding. Due to the incorporation of TOCNs, the TOCN/PNIPAM hydrogel exhibits a high compressive strength (~89.2 kPa), elongation at break (~170.7 %) and tensile strength (~24.0 kPa). The prepared PNIPAM/TOCN/PAM hydrogel actuator performs the roles of an encapsulation, jack, temperature-controlled fluid valve and temperature-control manipulator. The incorporation of Fe³⁺ further endows the bilayer hydrogel actuator with a synergistic performance of shape memory and temperature-driven, which can be used as a temperature-responsive switch to detect ambient temperature. The PNIPAM/TOCN/PAM-Fe³⁺ conductive hydrogel can be assembled into a flexible sensor and generate sensing signals when driven by temperature changes to achieve real-time feedback. This research may lead to new insights into the design and manufacturing of intelligent flexible soft robots.

Keywords: Hydrogels; Nanocellulose; Poly(N-isopropylacrylamide); Polyacrylamide; Temperature-responsive actuators.