Polyurethane coating and preparation method thereof

Abstract

The invention provides a polyurethane coating which is prepared from the following components in parts by weight: 55 to 65 parts of self-emulsifying double-acid modified polyurethane emulsion, 10 to 20 parts of water, 0.5 to 1.5 parts of dispersing agent, 0.5 to 2 parts of rheological additive, 25 to 35 parts of pigment filler, 0.1 to 0.5 part of coalescing agent and 0.1 to 0.2 part of base material wetting agent. The invention also provides a preparation method of the polyurethane coating. The preparation method comprises the following steps: S1, adding 80% of water into a reaction kettle; S2, starting the stirrer, adding the dispersing agent and the rheological additive according to the formula ratio, and uniformly stirring; S3, adding a formula amount of pigment and filler, and uniformly stirring at a high speed; S4, reducing the rotating speed of the stirrer, adding water accounting for 10% of the formula amount, brushing the tank, and grinding through a grinding machine; S5, aftergrinding until the fineness is less than 20 microns, putting into a batching tank, supplementing a formula amount of self-emulsifying double-acid modified polyurethane emulsion, and uniformly stirring; S6, supplementing the balance of water; and adding the coalescing agent and the base material wetting agent according to the formula ratio to obtain the coating. The polyurethane coating is excellent in film formation and environment-friendly.

Description

technical field [0001] The invention relates to the field of polyurethane coatings, in particular to a polyurethane coating and a preparation method thereof. Background technique [0002] With the development of modern industry and the continuous enhancement of people's awareness of environmental protection, the production and development of coatings are developing towards environmentally friendly coatings, that is, improving the quality of coating films, optimizing economic efficiency, being friendly to ecology, and saving energy. High-performance water-based coatings emerged as the times require. At present, the development of water-based coatings in my country has been widely developed and promoted in architectural coatings and wood coatings. However, due to technical defects and deficiencies, the application rate of water-based industrial coatings is less than 15% of the share. . In the past, coating companies basically dominated the world with paint and coatings, and th...

AI Technical Summary

Problems solved by technology

[0004] 1. The water-based acrylic polyurethane topcoats currently on the market are often shoddy, with a solid content ranging from 30 to 45%, and a slightly better solid content is only about 50%. The solid content is seriously insufficient, and the film thickness at one time is very high. Thin, for industrial anti-corrosion indicators with thickness requirements, it needs to be painted several times, not to mention wasting energy consumption, but also causing a lot of paint mist and dust

[0005] 2. The commercially available products with high solid content, the storage stability of the coating is not good, and there is a large amount of settlement and hardening in the packaging barrel in a short period of time; the construction is easy to sag, and the ideal coating that is uniform and beautiful cannot be obtained

[0006] 3. Commercially available water-based acrylic polyurethane topcoats often add a large amount of co-solvents and film-forming additives, resulting in the voc volatile organic compounds of the coating far exceeding the standard, which does not meet the national environmental protection indicators

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