Silica coatings inorganic

Oh, S.J. Cook, D.C. Townsend, H.E. (1998) Characterization of iron oxides commonly formed as corrosion products on steel. Hyper-fine Interactions 112 59-65 Ohmori, M. Matijevic, E. (1992) Preparation and properties of uniform coated inorganic colloidal particles. VII. Silica on hematite. J. Colloid Interface Sci. 150 594-598 Ohta, S. Effendi, S. Tanaka, N. Miura S. (1993) Ultisols of lowland Dipterocarp forest in East Kalimantan, Indonesia. Soil Sci. Plant Nutr. 39 1-12... 

Ohmori, M., and Matijevic, E., Preparation and properties of uniform coated inorganic colloidal particles 8 Silica on iron, J. Colloid Interface Set, 160, 288, 1993. 

Attempts have been made to design packings with an expanded pH compatibility compared to silica, but with a hardness comparable to silica. Other inorganic carriers such as alumina, titania, and zirconia have been explored. Indeed, their hardness matches that of silica, and being impervious to small molecules, they also exhibit the same advantageous mass-transfer properties as silica. However, no simple surface modification techniques are available as yet that match the silanization chemistry used for silica. Therefore, polymeric coatings have been used, which then in turn exhibit inferior mass-transfer behavior. 

M. Ohmori and E. Matijevic Preparation and Proeprties of Uniform Coated Inorganic Colloidal Particles. VII. Silica on Hematite. J. Colloid Interface Sci., 150, 594-598 (1992). 

For example, when silica-coated photoconductive CdS nanopartides were used as inorganic partides, the resultant materials were shown to retain the photolumi-nescent properties of the core. However, no mention was made about the colloidal stability of these systems. 

As the substrate sheet, a thin plastic film or tightly packed nonwoven cloth, such as polyester spanbond nonwoven cloth of approximately 0.15 mm, is used. A synthetic rubber, such as styrene-butadiene rubber or thermoplastic polyurethane elastomer, is used as a binder. In addition, a surfactant for hydrophilicity, an antioxidant for prevention of thermodeformation, and a silica-type inorganic filler for prevention of tackiness are used. For the superabsorbent polymer particles, various synthetic polymers, for example, polyacrylate and polyvinyl-type superabsorbent polymers, can be used. For this apphcation, the particle sizes are an important parameter, because they polymer is required to be within the coating layer, and as the absorption rate is no retarded, quickly protrude from the layer when swelling. 

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