Waterborne epoxy anticorrosive coating and preparation method thereof

Abstract

The invention discloses a waterborne epoxy anticorrosive coating and a preparation method thereof. The aqueous epoxy anticorrosive coating contains a component A and a component B according to a massratio of the component A to the component B of (3 to 5): 1. The component A comprises, by mass, 35-40 parts of a waterborne epoxy emulsion, 1-2 parts of carbon black, 10-15 parts of mica powder, 10-15parts of precipitated barium sulfate, 5-10 parts of graphene oxide / alkylbenzene sulfonate, 1-2 parts of a wetting dispersant, 0.3-0.5 parts of an antifoaming agent, 0.3-0.5 parts of a leveling agent,1-2 parts of a thixotropic agent and 20-30 parts of deionized water. The component B comprises, by mass, 7-10 parts of an aqueous epoxy curing agent, 3-5 parts of a cosolvent, 10-15 parts of deionized water and 1-3 parts of an amino group-containing silicone monomer. The waterborne epoxy anticorrosive coating has excellent anti-corrosion performance, good adhesion and resistance to cathodic disbonding, and is suitable for application in a marine environment.

Description

technical field [0001] The invention belongs to the technical field of water-based paint anticorrosion, and in particular relates to a water-based epoxy anticorrosion paint mainly used for heavy anticorrosion in marine environments and a preparation method thereof. Background technique [0002] Solvent-based epoxy coating has good physical and chemical properties, it has excellent bonding strength to the surface of metal materials, and has excellent anti-corrosion performance. Therefore, the epoxy coating anti-corrosion system is currently recognized as the best anti-corrosion performance and the most widely used coating system. No matter in marine anti-corrosion or industrial anti-corrosion, the demand for epoxy coatings is very large. However, the content of volatile organic compounds in coatings is limited at home and abroad, and water-based anti-corrosion coatings have received widespread attention and application. [0003] The anticorrosion of water-based epoxy systems...

AI Technical Summary

Problems solved by technology

[0003] The anticorrosion of water-based epoxy systems mostly relies on anticorrosion fillers, but the anticorrosion fillers used are mostly zinc phosphate, aluminum tripolyphosphate, etc., the marine heavy-duty anticorrosion effect is poor, and the enrichment of phosphate ions will pollute the environment to a certain extent

With the development of graphene technology, graphene is gradually applied in anti-corrosion, but the conjugation effect between graphene makes graphene easy to agglomerate, poor dispersion in water-based system, and there are gaps in the microstructure of the coating after curing. Water molecules and ions are easily permeable, and there are no active groups on the surface of graphene, so it is difficult to modify it. However, oxidized graphene contains more hydrophilic groups, which cannot be chemically modified and can be used alone Unsatisfactory anti-corrosion effect

[0004] It is recorded in the existing literature that graphene oxide is coupled with polyaniline, and then prepared with nano-scale silicon dioxide to form a composite anti-corrosion powder. This method can improve the anti-corrosion effect to a certain extent, but polyaniline itself has a high oxidation resistance. Reduction, used in marine heavy-duty anti-corrosion environment, there are more oxygen atoms and salt ions, which are easy to cause oxidation aging of the coating and electrochemical corrosion of the substrate

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