Views: 3 Author: Site Editor Publish Time: 2021-07-26 Origin: Site
Polyurea spray equipment is usually used in construction, mainly because polyurea has a strong anti-corrosion effect. Has a certain adhesion and strength. In order to improve the adhesion of the coating, it is necessary to strictly control the substrate used and improve it if necessary, so the polyurea spraying equipment has a variety of adhesion to the surface of the object. However.
1. Mechanical adhesion: Mechanical adhesion is related to the surface roughness of the object. In fact, the surface area of a rough surface is greater than that of a smooth surface, and the area where the coating adheres to the substrate also increases; combined with a certain rough shape, the coating forms a "straightened" bond with the surface of the rough substrate. , The adhesion will increase.
2. Chemical bond adhesion: The chemical bond produced by chemical reaction is an effective method for polyurethane sprayer coating to adhere to the surface of the object. An example is a metal hot-dip coating, which produces a mixture of steel and metallic zinc on the steel surface and melts each other. The silicate molecules in the inorganic zinc-rich primer also form chemical bonds with the steel surface. These bonds are the actual reaction between the chemical functional groups of the coating and the components of the substrate to form chemical bonds.
3. Polar adhesion: Compared with the adhesion caused by chemical bonds, the adhesion caused by polarity is more common in organic coatings. The polar adhesion of the polyurea sprayer is the attraction of resin molecules to the surface of the substrate. In this case, the resin acts like a weak magnet, attracting the opposite groups of the substrate from the north and south. This is the meaning of "extreme". In fact, the polar group is the positive or negative charge in the coating molecule, which can attract the opposite charge of the substrate.
The anticorrosive coating of polyurea spray equipment has low permeability and water permeability. You can use a base material with lower air permeability as a filler material. If peeling occurs during construction, it is caused by the surface of the building, so you must analyze the specific situation of the building.