Transparent, Antifreezing, Ionic Conductive Cellulose Hydrogel with Stable Sensitivity at Subzero Temperature

ACS Appl Mater Interfaces. 2019 Nov 6;11(44):41710-41716. doi: 10.1021/acsami.9b15849. Epub 2019 Oct 23.

Abstract

Cellulose was dissolved in benzyltrimethyl ammonium hydroxide (BzMe3NOH) aqueous solution, and ionic conductive cellulose hydrogels (CCHs) with antifreezing property were directly fabricated by chemical cross-linking, without further treatment. The concentrated BzMe3NOH solution in the CCH matrix endowed the hydrogel with transparency, ionic conductivity, and freeze tolerance. CCH maintained transparency over 90% and stable mechanical properties in the temperatures from -27.8 to 62.1 °C. Furthermore, the CCH-based sensors exhibited stable sensitivity to tensile strain, compressive pressure, and temperature, in a wide temperature range including the subzero temperature, with a fast responding time and no obvious hysteresis. The present work is expected to provide a simple and sustainable pathway to prepare an antifreezing soft conductor with multifunctions based on cellulose, which enables a broad range of potential applications.

Keywords: antifreezing; aqueous solvent; cellulose; conductive hydrogel; sensor.