Cellulose nanofibril enhanced ionic conductive hydrogels with high stretchability, high toughness and self-adhesive ability for flexible strain sensors

Mengqian Shi; Ya Liang; Chengyu Zhang; Na Li; Yunfeng Li; Xiaojiao Shi; Zhihui Qin; Tifeng Jiao

doi:10.1016/j.ijbiomac.2024.139297

Cellulose nanofibril enhanced ionic conductive hydrogels with high stretchability, high toughness and self-adhesive ability for flexible strain sensors

Int J Biol Macromol. 2024 Dec 28:293:139297. doi: 10.1016/j.ijbiomac.2024.139297. Online ahead of print.

Authors

Mengqian Shi¹, Ya Liang¹, Chengyu Zhang², Na Li¹, Yunfeng Li¹, Xiaojiao Shi¹, Zhihui Qin³, Tifeng Jiao⁴

Affiliations

¹ State Key Laboratory of Metastable Materials Science and Technology, Hebei Key Laboratory of Applied Chemistry, Hebei Key Laboratory of Nanobiotechnology, Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource Reuse, Yanshan University, Qinhuangdao 066004, China.
² Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore.
³ State Key Laboratory of Metastable Materials Science and Technology, Hebei Key Laboratory of Applied Chemistry, Hebei Key Laboratory of Nanobiotechnology, Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource Reuse, Yanshan University, Qinhuangdao 066004, China; Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore. Electronic address: [email protected].
⁴ State Key Laboratory of Metastable Materials Science and Technology, Hebei Key Laboratory of Applied Chemistry, Hebei Key Laboratory of Nanobiotechnology, Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource Reuse, Yanshan University, Qinhuangdao 066004, China. Electronic address: [email protected].

PMID: 39736292
DOI: 10.1016/j.ijbiomac.2024.139297

Abstract

Preparation of ion-conductive hydrogels with excellent mechanics, good conductivity and adhesiveness is promising for flexible sensors, but remains a challenge. Here, we prepare a self-adhesive and ion-conductive hydrogel by introducing cellulose nanofibers (CNF) and ZnSO₄ into a covalently-crosslinked poly (acrylamide-co-2-acrylamide-2-methyl propane sulfonic acid) (P(AM-co-AMPS)) network. Owing to the hydrogen bonding and metal coordination interactions among P(AM-co-AMPS) chains, CNF, and Zn²⁺, the resulting P(AM-co-AMPS)/CNF/ZnSO₄ hydrogel exhibits high stretchability (1092 %), high toughness (244 kJ m^-3), and skin-like elasticity (3.53 kPa). Moreover, the hydrogel has strong adhesion with different substrates by multiple non-covalent interfacial interactions. The SO₃^- on AMPS and COO^- on CNF largely promptes the ionic migration (Zn²⁺, SO₄^2-) through electrostatic interaction and hydrogen bonding, thus the hydrogel has high ion conductivity (5.85 S m^-1). Finally, this hydrogel has high strain-sensitivity in a wide strain range, exhibiting great potential applications in wearable sensors.

Keywords: Cellulose nanofibril; High stretchability; Ionic conductive hydrogel; Self-adhesion.