Hot Keywords: Sol precision castings
Silica inorganic polymer coatings in recent years to develop. The key technology for preparing the paint is removed with a special water glass water-soluble sodium ions. Generally by ion exchange, acid neutralization, hydrolysis, other methods to achieve electrodialysis, ultrafine silica particles to form a very fine colloidal solution, a particle size of 580nm (typically 800-1,000 nm, as emulsion particles) wherein Si2O content of 20% -30%, the proportion of Na2O content of 0.3% ¥, silicon oxide and sodium oxide above 40%. In this silicon solution / gum base, with pigments and various additives and inorganic polymer coating made of silica. Silicon solution loses moisture gradually silicic acid monomers polymerized into high polymer silica gel, with the evaporation of water, colloidal molecules increases, and finally the formation -SIO-O-SIO- film: IO-SI-OH + HO-SI- OH NA2O due to the low content of silica sol, silica sol having a film-forming amount of dissolution characteristics, water resistance, heat resistance significantly better than organic coatings. Dense and hard coating, does not produce static electricity, dust in the air in a variety of difficult adhesion. In the current architectural coatings, it is a strong anti-pollution ability.
Fine particles, there is a strong grassroots penetration through the capillary penetration inside to the grassroots and can generate calcium silicate concrete base in a reaction with calcium hydroxide, the coating has a strong adhesion.
But sol volume shrinkage during film formation is large, the film is easy to crack. Sol can compatibility with any acrylate latex, vinyl acetate and the like. The characteristics of both complement each other, it can be formulated with excellent performance of organic and inorganic composite coatings.