Research On Regulation Of Surface Lubrication And Wetting Of Electric-responsive Supramolecular Lubricating Hydrogel

Supramolecular intelligent response hydrogel can undergo phase transformation under the action of external stimulation such as force,light,electric field,pH,temperature and so on,which makes its physical and chemical properties changed.It has a great application in soft robot,artificial skin,drug delivery and the like.By synergizing supramolecular non-covalent and polymer covalent network,a responsive supramolecular lubricating hydrogel with partial gel-sol transformation capability has been prepared and used in the development of lubrication devices.Due to its easy of application,rapid response,low cost and huge application potential,electric field has gradually become one of the main stimulation methods of intelligent responsive devices.In this thesis,an electric-responsive supramolecular lubricating hydrogel with partial gel-sol transformation ability have been designed and developed based on the synergistic effect of the electric response silk fibroin supramolecular non-covalent section and the covalent network(polyacrylamide/polyvinyl alcohol).Among them,the silk fibroin supramolecular section is disassembled in the vicinity of the cathode under the action of electric field,and along with gel-sol transformation,a lubricating layer is formed on the surface of the hydrogel so as to control the lubrication of the hydrogel surface.At the same time,the covalent network(polyacrylamide/polyvinyl alcohol)provides sufficient mechanical support for the gel,so that the material has partial gel-sol transformation capability while maintaining good mechanical strength.At the same time,the surface of the hydrogel produced a lubricating layer under the action of electric field,and its hydrophilicity was further improved.Its wettability in oil has intelligent response too.In the oil environment,the water contact angle will change from 139.4±4° to 62.7±6.6°,and the wettability of the gel will change from the underwater hydrophobic to the hydrophilic state.This research provides a possible idea for the design and fabrication of electric-responsive water separation devices.In summary,the electric-responsive semi-convertible hydrogel prepared by introducing an electric-responsive non-covalent supramolecular section into a covalent network,producing a lubricating layer on the surface of the hydrogel under the action of the electric field,thus regulating the lubricity of the hydrogel surface.At the same time,the wettability of the material changes from hydrophobic to hydrophilic in oil under the action of electric field.The electric-responsive supramolecular lubricating hydrogel,which provides a new idea for the design and manufacture of soft robots,smart devices and wearable devices.