What should I do if the water-based paint has poor water resistance?

Water-based coatings use water-based polymers as the film-forming material, which not only reduces VOC emissions, but also has the advantages of safety, no fire hazards, construction in humid environments, and convenient cleaning

The water resistance of a coating refers to the resistance of the paint film to the action of water .

The paint film is affected by water mainly in two aspects: First, the paint film has strong water absorption and is easy to regain moisture (or dry slowly, not easy to dry completely)

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So how to improve the water resistance of the paint film?

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Increase the crosslinking density of the paint film and the completeness of the curing reaction
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Choose high-end resin dispersion with hydroxyl value and appropriate additives to ensure that the paint film has a higher crosslinking density after curing
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Of course, the additives should be added in an appropriate amount, too much will reduce the water resistance
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Reduce the surface tension of the paint film
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After the surface tension of the paint film is reduced, it will have a certain degree of hydrophobicity, which can be achieved by using siloxane leveling agents
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The above methods are more effective to improve the water resistance of water-based coatings
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However, China's climatic conditions are diverse, the south is hot and humid, and the north has a long frost period.
The time window to meet the good climatic conditions for the construction of water-based anti-corrosion coatings is indeed limited, which will limit the promotion and application of water-based coatings
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In addition, compared with the currently used solvent-based, high-solid and solvent-free coatings, water-based coatings still have poor thick coating properties and cannot be used in harsh corrosive environments
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In the long run, the contribution of volatile organic chemicals in various coatings to PM2.
5 and the harm to the environment determine that water-based coatings are the future development direction of the coatings industry, and the improvement of various properties of water-based coatings has become the focus.
Research content
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