Acrylic leveling agent: a key additive to improve coating performance

1. Composition and structure

Acrylic leveling agents are generally made from acrylic monomers through polymerization reactions. Common monomers include methyl acrylate, ethyl acrylate, butyl acrylate, etc. By combining different monomers and adjusting the polymerization process, acrylic leveling agents with different molecular weights, molecular structures and performance characteristics can be obtained. Its molecular structure usually contains polar groups and non-polar groups. This structural feature enables it to play a unique role in the coating system.

2. Working principle

Reduce surface tension: During the construction process of the coating, good leveling requires uniform and low surface tension of the coating. Acrylic leveling agents can migrate to the surface of the coating, and the non-polar groups in its molecules face the air side. The polar groups interact with the film-forming substances in the coating, thereby reducing the surface tension of the coating and the air interface, allowing the coating to spread better and reduce surface defects such as shrinkage cavities and orange peel.

Improve fluidity: It can adjust the rheological properties of the coating, reduce the viscosity of the coating under the action of construction shear force, and make the coating easier to flow and level. When the shear force disappears, the viscosity of the coating can be quickly restored to prevent the occurrence of sagging and ensure uniform coating thickness.

Promote molecular diffusion: Acrylic leveling agents can promote the mutual diffusion of high molecular weight polymer molecules in the coating, making the molecular composition and arrangement of different areas more uniform, thereby improving the flatness and glossiness of the coating.

3. Functional performance in coatings

Improve surface flatness: effectively eliminate the tiny unevenness on the coating surface, making the coating surface as smooth as a mirror. In furniture coatings, after using acrylic leveling agents, the furniture surface is smoother and feels better, which improves the quality and grade of the furniture.

Enhance gloss: The flat coating surface can reflect light more effectively, thereby significantly improving the glossiness of the coating. In automotive topcoats, the use of acrylic leveling agents gives the car body a bright gloss and enhances the appearance of the car.

Prevent shrinkage and orange peel phenomenon: By reducing surface tension, shrinkage on the coating surface due to tension differences is avoided; at the same time, the fluidity is improved so that the coating can be evenly leveled during the drying process to prevent the appearance of orange peel-like surface unevenness. In architectural coatings, this helps to obtain beautiful and uniform wall coatings.

Improve adhesion: It can improve the wettability between the coating and the substrate, make the coating adhere better to the surface of the substrate, enhance the bonding force between the coating and the substrate, and improve the durability of the coating.

4. Precautions for use

Dosage control: The dosage of acrylic leveling agent needs to be strictly controlled. If the dosage is too small, it may not be able to fully exert its leveling effect; if the dosage is too large, it may cause the coating to become sticky and reduce water resistance. Generally speaking, its dosage is usually 0.1% - 2% of the total amount of the coating. The specific dosage needs to be determined through experiments based on the coating system, construction process and actual needs.

Compatibility: Make sure that the acrylic leveling agent has good compatibility with other components in the coating. If the compatibility is poor, the leveling agent may precipitate and float in the coating, which will affect the quality of the coating. Before use, a compatibility test is required to select a leveling agent product that matches the coating system.

Construction conditions: The temperature, humidity and other conditions of the construction environment also have a certain impact on the effect of the acrylic leveling agent. Generally speaking, the suitable construction temperature is 15℃ - 35℃ and the relative humidity is 40% - 70%. Under extreme temperature and humidity conditions, the performance of the leveling agent may be affected, resulting in poor leveling effect.