Preparation And Properties Of Conductive Composite Hydrogel Based On Nanocellulose/Graphite Oxide/Polyaniline Composite

Flexible sensors are widely used in fields such as human physiological health detection,human-machine interaction,and electronic skin due to their good plasticity,small size,and ease of wear.As one of the active materials for flexible sensors,hydrogels have shown great advantages in good extensibility,adhesion and chemical stability.Hydrogel is a three-dimensional network structure composed of cross-linked and entangled polymer particles,which is suitable for conducting conductive polymers,carbon based materials,ions and other conductive particles.However,the biological incompatibility and low sensitivity of conductive fillers greatly affect its application.Therefore,the preparation of conductive composite hydrogels with tensile,antifreeze,conductive,adhesive,sensing and other functions has become a research hotspot.This project combines nano cellulose(CNC)as an adhesive and toughening agent,polyaniline(PANI)and graphene oxide(GO)as conductive fillers into different polymer network hydrogels to prepare two different functional composite conductive hydrogels based on nano cellulose/graphene oxide/polyaniline.(1)Preparation and properties of high tensile self-adhesive composite conductive hydrogelUsing polyacrylamide(PAM)hydrogel as the substrate for conductive hydrogels,different components of nanocellulose,graphene oxide,and polyaniline were added to monomer acrylamide(AM)for in situ polymerization in one pot method.The PAM/CNC/GO/PANI composite conductive hydrogel was prepared by pouring it into a model and solidifying under ultraviolet lamp radiation(UV).After freeze-drying the composite hydrogel,scanning electron microscopy(SEM)and Fourier transform infrared spectroscopy(FT-IR)were used to characterize and analyze the effects of adding CNC,GO,and PANI components on the microstructure and chemical structure of the conductive hydrogel.Conduct tensile fracture testing on the hydrogel to investigate the effects of each component on its mechanical properties.When the CNC is 0.65 wt%,PANI is 1 wt%,and GO is 1 wt%,the conductive hydrogel has the best mechanical properties,with a tensile strength of approximately 3.7 times that of pure PAM gel,a tensile fracture elongation of about 6 times that of pure PAM gel,and a toughness of 20 times that of pure PAM hydrogel.In addition,composite conductive hydrogels have good chemical stability,adhesion,high strain sensitivity,cyclic stability,and instantaneous response to strain energy in the range of 0% to 300%.They have potential application prospects in detecting human physiological health,human-machine interaction,and wearable devices.(2)Preparation and properties of antifreeze self-healing ability conductive composite hydrogelUsing polyvinyl alcohol(PVA)gel as the substrate for composite conductive hydrogels,two organic solvents,ethylene glycol(EG)and dimethyl sulfoxide(DMSO),were used to replace traditional solvents.PVA was dissolved at high temperature,and then nano cellulose,graphene oxide,and polyaniline were introduced to prepare PVA/CNC/GO/PANI composite conductive hydrogels through cyclic freeze-thaw.Study the effects of factors such as CNC content,GO content,PANI content,and different organic solvents on the mechanical properties of conductive hydrogels.The self-healing ability and water retention performance of the composite conductive hydrogel prepared with two solvents ensure normal use in special environments.In addition,composite conductive hydrogels have excellent durability,wide sensing range,and higher sensitivity,which can monitor human motion in real-time(such as finger bending and wrist rotation),providing more possibilities for practical applications of hydrogels.