Study Of Self-lubricating And Self-healing Coating Based On Epoxy Resin

Epoxy resin is a thermosetting material with excellent performance and is commonly used as a matrix in composite coating materials.The coating material is prone to micro-cracks that are difficult to repair during long-term use,which greatly reduces its mechanical properties and life.Microcapsule technology is a kind of protection technology that uses functional solid,liquid or gas as the core material,encapsulates it with shell material to form microcapsules,and releases the core material if necessary.In this paper,two microcapsules,self-lubricating and self-repairing,were prepared by in-situ polymerization.The morphology and structure of the microcapsules were studied using Fourier infrared spectrometer,optical microscope,scanning electron microscope,ultraviolet lamp and friction and wear machine.The microcapsules were embedded in an epoxy resin matrix,and their lubrication and self-healing effects were tested by scratch experiments.The main study are summarized as follows:(1)The self-lubricating system selects polyurea formaldehyde as the wall of the self-lubricating microcapsules and soybean oil as the core of the microcapsules.The self-lubricating microcapsules were synthesized by in-situ polymerization,and a color-developing agent was added for warning.Its surface morphology,chemical structure and tribological properties.(2)The self-healing system uses melamine-urea-formaldehyde polymer resin as the wall material of the self-healing microcapsules,and epoxy resin as the core material of the microcapsules.The MUF-coated KH-560 modified epoxy was prepared by in-situ polymerization The microcapsules and emulsified epoxy microcapsules were tested for their morphology,structure and performance.(3)Apply the prepared self-lubricating and self-repairing microcapsules to the epoxy resin coating to prepare the epoxy resin self-lubricating and self-repairing coating,and the tribological properties,self-lubrication and self-repairing of the coating The performance was studied and the self-lubricating and self-repairing mechanism of the coating was discussed.(4)Developed better synthetic process conditions,successfully prepared two functional microcapsules with self-lubrication and self-repair.It proves that the formation mechanism of microcapsules made with lubricating oil and repair agent as core materials is the same.During the formation of microcapsules,the pH and reaction temperature of the solution determine the rate of polycondensation and the degree of crosslinking of the prepolymer molecules.The coating treatment of the wall material obviously improves the stability of the lubricant and the repair agent,and effectively plays the role of isolating and protecting the core material.(5)The formation of microcapsules divided into three stages of emulsification,polycondensation and crosslinking,curing.The core material is uniformly dispersed in the emulsion to form micron-sized particles;then under acidic and heated conditions,the wall material prepolymer is electrostatically adsorbed and precipitated.The deposit forms an initial wall material with low strength on the surface of the core material;and the wall material continuously accumulates,crosslinks and solidifies.Finally microcapsules were formed with excellent performance.