Preparation and properties of polyacrylamide/cellulose nanocrystal/reduced graphene oxide interpenetrating network composite hydrogels

Abstract

In this paper, acrylamide (AM), cellulose nanocrystals (CNCs), and reduced graphene oxide (rGO) were used as raw materials to prepare PAM/CNC/rGO interpenetrating network composite hydrogels by in situ free radical polymerization. Ions were introduced by soaking the composite hydrogels in an ionic solution. The composite hydrogels were characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) and tested for their mechanical, electrical, sensing, and water-retention properties. When 0.15 g of rGO was added, the composite hydrogel exhibited a large elongation at break (up to 680%) and tensile strength (0.28 MPa). The composite hydrogel has a high sensitivity factor (11.79) in the strain range of 300–400%, showing excellent strain sensitivity. After being immersed in 0.3 mol L⁻¹ calcium chloride solution for 3 h, the conductivity of the composite hydrogel reached 3.39 S m⁻¹, showing good conductivity. Therefore, the PAM/CNC/rGO interpenetrating network composite hydrogel has potential application value in the field of flexible sensors.