Colloidal silica preparation method

Inorganic polymer coating of silica sol preparation process no special difference between the other coating, but should be slowly added Colloidal silica, or paint will change in nature. You can take off work the following preparation: the film-forming additives (often made with the use of zinc oxide, silicic acid ester, butyl acetate, methyl-sodium) added to the reaction kettle, add water, mixing quantitative and turn adding surfactant (benzene sulfonate), thickeners (hydroxyethyl cellulose, CMC, etc.), dispersant (sodium side door), defoamer (TBP) and other additives; and then slowly adding Colloidal silica, pigment, color paste. Sanding machine or a colloid mill with a small study, need to join the middle points can be coarse aggregates. PH value of the coating needs of 8.510 between. Colloidal silica  inorganic polymer coating formulation: greater shrinkage during sol film, coating easy to crack, to overcome this drawback, in addition to adding the inorganic fibrous filler coating, while also adding water-soluble emulsion as a supplement to membrane material, so that organic matter fill in "-Si-O-Si-", network structure to reduce the film shrinkage and expansion and contraction caused by temperature changes. Into a coating that has excellent weather resistance of inorganic, organic coatings, as they have excellent decoration, stability and construction of the organic compound coating. This test can usually filter: in the inorganic material film accounted for 50% to 90%, 10% and 50% organic matter. When added in with the polyvinyl acetate emulsion; to add external benzene - acrylic emulsion, the first use of rutile titanium dioxide, the volume concentration of 5%, and mixed with a lot of pigment, the total volume concentration of 60% 70% speculation

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