Preparation And Properties Of Carboxymethyl Cellulose Based Conductive Hydrogel

Due to the high tunability,conductive hydrogels could provide the high ionic?electronic?conductivity,electrochemical activity,flexibility and electrolyte permeability,etc.,attracting much attentions as the next generation of electronic devices.Currently,the mechanical strength and conductivity of conducting hydrogels are genernally low to meet real applications.Herein,the carboxymethyl cellulose was introduced into the chemically cross-linked polyacrylamide network to perpare the ionically and electronically conductive hydrogels with high mechanical property and condutivity,respectively.Moreover,the sensing and electrochemical properties were evaluated.The specific work is mainly divided into the following two parts:In the first part,in order to improve the mechanical strength of the conducting hydrogel,the physical cross-linked network of Fe³⁺complexed with carboxyl groups was fabricated on the basis of chemically cross-linked polyacrylamide networks through solvent replacement.The fracture stress and toughness could attain 900 kPa and 5238 kJ/m³,respectively.Under the existence of the interconnectedly porous structure and water molecular channels,the ionic transmission was realized imparting the hydrogel with the strain responsive property acted as sensors.In addition,the sensing performance,sensitivity,responsiveness and stability were discussed laying a foundation for the application of conducting hydrogels in the field of human-machine interaction.The introduction of ethylene glycol limits the crystallization and volatilization inside the gel,which endows the hydrogel with anti-freezing and anti-drying performance widening the operating temperature.In the second part,in order to further improve the conductivity,the carboxymethyl cellulose/polypyrrole conductive particles were in situ formed in the chemically cross-linked polyacrylamide hydrogel.As a result,combined with the three-dimensional network,a stable interconnected electron conductive path is formed,and the conductivity attaines as high as11.07 S/m,which is used as the flexible supercapacitor electrode.At the current density of0.2 A/g,the specific capacitance of the hydrogel is 126.38 F/g.At the same time,the hydrogel also has the unique visible light transmission and UV-shielding performances.In addition,there are a large number of hydroxyl,amino and carboxyl groups inside the hydrogel showing excellent interfacial adhesion.