Water based paints often appear white after soaking in water

Waterborne paint often turns white after being soaked in water. This is because the hydrophilic substances in the water-based paint film keep accumulating. Under the action of osmotic pressure and the driving force of hydrophilic substances, water enters the film. When light passes through the film, scattering occurs due to the difference in refractive index between water and resin or lotion, so that the film becomes white.

Taking the application of water-based wood varnish as an example. The traditional acrylate lotion has the contradictory phenomenon of anti adhesion and water white resistance. The main reason is that the acrylate lotion is affected by its molecular structure, which has the characteristics of hot viscosity and cold brittleness. Therefore, the acrylate lotion will become sticky under the environment of high temperature. In the prior art, in order to solve this problem, the method of improving the surface hardness of polymer particles is usually used to overcome the defect of high temperature stickiness of acrylate lotion. However, as the surface hardness of polymer particles increases, the rigidity of molecular chains also increases, leading to an increase in the brittleness of the paint film. In addition, due to the increased rigidity of the molecular chain, the light resistance of the molecular chain is poor under light irradiation, and the functional groups on the molecular chain are prone to migration, greatly reducing the water whitening resistance of the paint film. Adhesion resistance and water whiteness resistance are contradictory properties for acrylate lotion, and they cannot have both. Therefore, how to develop an acrylate lotion with both excellent adhesion resistance and good water whiteness resistance is a technical problem in the acrylate lotion industry at present.

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