Special low-temperature curing powder coating for electrostatic spraying and preparation method thereof

Abstract

The invention relates to a special low-temperature curing powder coating for electrostatic spraying and a preparation method thereof. The powder coating is prepared from the following raw materials in parts by weight: 55-75 parts of polyester resin, 15-25 parts of epoxy resin, 5-10 parts of organic silicon resin, 2-8 parts of modified carbon nano tubes, 1-3 parts of graphite powder, 2-6 parts of white carbon black, 5-15 parts of titanium dioxide, 5-40 parts of filler, 1-10 parts of a pigment, 2-5 parts of a curing agent, 0.05-0.5 part of a curing catalyst, 1-3 parts of a flatting agent, 1-3 parts of a dispersing agent, 0.1-0.5 part of a coupling agent and 1-5 parts of a styrene-acrylic emulsion. The powder coating has the advantages of being simple in formula, low in curing temperature, good in mechanical property, smooth in film, high in adhesive force and stable to store, electrostatic spraying can be achieved, the construction difficulty is reduced and the work efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of powder coatings, in particular to a special low-temperature curing powder coating for electrostatic spraying and a preparation method thereof. Background technique [0002] Powder coating is a coating that contains 100% solid content and is applied in powder form. The biggest difference between it and general solvent-based and water-based coatings is that it does not use solvent or water as a dispersion medium. Because of the recyclable and reused spraying material in the coating process, no solvent volatilization, safe production and construction, easy automation of coating, and improved productivity, it has become a new coating product with rapid development. At present, powder coating has been proved to be a major technical achievement, and has entered a relatively mature stage of development. [0003] Powder coatings have their own production process characteristics and are not cured at low temperatu...

AI Technical Summary

Problems solved by technology

Powder coatings have their own production process characteristics, and the curing conditions are relatively harsh. The standard curing temperature is generally between 180-200 ° C, resulting in high energy consumption, and limiting the application of powder coatings on heat-sensitive substrates, hindering the application of powder coatings Therefore, low-temperature curing of powder coatings has become the development goal of the powder coating industry

[0004] Powder coating is a low-temperature latent curing system. If the system has high low-temperature reactivity, it will inevitably affect the powder milling extrusion process and storage stability. If the resin and curing agent used in the powder coating are relatively high softening Solids with a low softening point have high melt viscosity at low temperatures, and are difficult to level when solidified at low temperatures, which affects the surface effect. Using resins and curing agents with low softening points can reduce the melt viscosity of the system, but the storage stability of the powder will deteriorate. , need to be stored in low temperature refrigeration, which brings a lot of inconvenience to use; it can be seen that the key problem of powder coating ultra-low temperature curing technology is to find a system with a good balance between storage stability, melting, fluidity and curing

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