Latent self-repair microcapsule and preparation method thereof

Abstract

The invention belongs to the technical field of preparation of a microcapsule, and relates to a latent self-repair microcapsule for an organic coating and a preparation method of the latent self-repair microcapsule. The method comprises the steps of feeding urea and formaldehyde mixed solution into a four-mouth flask, adjusting the pH value to 7.5-11.8 with triethanolamine, and ensuring that the temperature is slowly increased for reaction for 3 hours, so as to produce viscous transparent water-soluble urea-formaldehyde prepolymer solution; sufficiently mixing a capsule-core epoxy resin, a capsule-core diluting agent, and a capsule-core latent curing modifier proportionally, adding distilled water, stirring, adding an emulsifying agent, emulsifying for 10-20min in a high-speed emulsifyingmachine, so as to form O / W type emulsion, mixing the urea-formaldehyde prepolymer solution and the emulsified liquid and sufficiently stirring to disperse in an aqueous medium, adjusting the pH valueto 1.0 to 5.0, centrifugating the particle suspension after curing at a controlled temperature for 3 hours, performing flushing for a plurality of times, and then performing vacuum drying to obtain the microcapsule. The method has the advantages that the technology is simple, the condition is easy to control, the preparation cost is low, the product quality is good, the repair effect is good, themanpower and cost are saved, and the method is environment-friendly.

Description

Technical field

[0001] The invention belongs to the technical field of microcapsule preparation, and relates to a latent self-repairing microcapsule used for organic coating and a preparation method thereof, in particular to a latent repairing agent type composite microcapsule and a preparation method thereof. Background technique:

[0002] At present, traditional crack repair techniques mainly include welding, repair, and in-situ curing of new resins. Most of these traditional methods use intermolecular interactions to repair some thermoplastic resins. The repair mechanism is non-covalent bond interactions between interface molecules. There is no new covalent bond formation, and a lot of manual labor is required; the self-repairing microcapsule technology used for coating crack repair has the characteristics of self-diagnosis and self-repair, which makes up for the loopholes in manual detection of coating defects and reduces labor workload . At present, dicyclopentadiene is use...