Through the dispersion of swelling or colloidal state in the paint, a similar network structure is formed, so as to achieve the purpose of anti sinking, or adsorb on the surface of the pigment and the filler, play a bridging role between the pigments, control the flocculation of the pigment and prevent sinking.
Silica has small particle size, large specific surface area and silanol group on its surface. These silanol groups interact with neighboring silica particles to form hydrogen bonds.
Hydrogen bonding makes it form contact deformation structure. Silicon dioxide is an ideal anti settling agent, which is very effective to prevent the deposition of pigment in the coating system.
Especially for the color paste system, proper addition will greatly improve the stability of the color paste, and reduce the amount of wetting dispersant, so as to improve the applicability of the color paste and reduce the influence of the color paste on the precipitation of the paint system.
The precipitate effect of silica is very favorable for coating storage, especially for some pigments, such as metal powder and flake, which are easy to precipitate and can not be completely suspended. The use of silica can ensure its dispersion and non precipitation. In completely nonpolar liquids, such as hydrocarbons and halogenated hydrocarbon solvents without hydrogen bonding ability, the viscosity recovery time only needs a fraction of a second; in polar liquids, such as amines, alcohols, carboxylic acids, aldehydes and diols with hydrogen bonding tendency, the recovery time can last for months, which depends on the concentration and dispersion of silica.
In order to improve the dispersing quality, the high-speed dispersing machine or three roller machine is usually used. If the dispersing is not enough, the coating film has particles, which affects the glossiness. Silica has been reported as an anti settling agent in copper acrylic conductive coatings. It has been proved by experiments that silica can make thixotropic properties of thermoplastic acrylic resin and prevent the deposition of filler particles, but with excessive addition, the coating becomes gel and the conductivity of the coating decreases.
Contact Us:
JINSHA PRECIPITATED SILICA MANUFACTURING CO.LTD.
Email.: jk@jksilica.com
Add.: Gaosha Industrial Zone, Shaxian, Fujian, China
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Room 908, Taiwan Street No.290, Xiamen, China
Mobile/WhatsApp:+86-17850500833
Contact: Wendy Wu, Sally Jiang
Tel.:+86-592-5528715
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