Chitin Hydrogel Fiber With Superior Strength, Biocompatibility, and Electrical Conductivity Fabrication by Blending Multi‐Walled Carbon Nanotube in Alkali/Urea Aqueous Solution

ABSTRACT The inherent low conductivity of chitin cannot meet the increasing demand for materials, which greatly hinders its practical utility. In this study, chitin solution was prepared by using an alkali/urea water system as a green solvent, and then a small amount of modified multi‐walled carbon nanotubes (CNTs) and epichlorohydrin (ECH) were added to the solution as functional fillers and crosslinking agents. Chitin/CNTs hydrogel fibers were prepared by a PVC hose mold. Hydrogel fiber has a uniform structure, excellent mechanical properties (tensile strength is 2.75 MPa, elongation at break is 127.9%, and toughness is 1.37 MJ/m 3 ), good biocompatibility (cell survival rate > 96%) and a certain conductivity (conductivity is 67.7 S/cm), which is 40 times the conductivity of chitin hydrogel fiber. It has a good application prospect in sensors, especially in monitoring human health and activities. This study provides guidance for expanding the application field of chitin.