Studies On Inorganic Coating Material With The Function Of Controlling Humidity Purifying Indoor Air And Antibacterial Action

Fibrin sepiolite and nano-TiO₂ were mixed together and separated, in order that nano-TiO₂ was dispersed and adsorbed by sepiolite fibrin. The performances of strong adsorption and big specific surface area of sepiolite were used to settle separation question of nano-materials and improve photocatalytic effect of nano-TiO₂. On above base, an environment-friendly inorganic powder coating for inner wall with the functions of adjusting humidity, killing bacteria and purifying indoor air has been manufactured.With the methods of XRD and SEM, the configuration and crystal phase were analyzed. With BET method, the specific surface area and pore diameter of sepiolite , nano-TiO₂ and their compound was measured. With SEM method, the composite material was analyzed and had found that nano-powders were separated around sepiolite fibre.With ESR method, the ability to produce hydroxyl radical of the compound was studied. It was found that the hydroxyl radical was produced not only under ultraviolet light (wavelength 355nm), but also visible light (wavelength 532nm), even without visible-ultraviolet light.For the above performance, there are two critical factors to explain it with sepiolite involvement. One is the acidity site which takes part in the photocatalytic reaction. The other is metal ions from sepiolite such as Fe³⁺ and Mn²⁺, which can be settled on the defects on the nano-TiO₂ surface and reduce the re-combination rate of e^- electron and h⁺ holl. So the ability of photocalysis is improved. And also, the capability was supported by the experiment of decomposing methyl orange in aqueous solution.A series of experiments and analysis have been conducted in the paper. Firstly, the morphology, structure and poral type were studied to mineral materials (sepiolite, diatomite, attapulgite, zeolite) with methods of XRD and SEM and BET. Secondly, the capability of humidity adsorption-desorption and the mechanism were also researched in this paper. Then, it also evaluated the relationship among ability, specific surface area and aperture. It comes out that the moisture capability is very related to capillary effect and surface potential.Based on above experiments and the results, a new inorganic powder coating was developed. Through testing, the product was proved to have good performances of construction and decoration. Moreover, its performance of resisting scrub meets the first class of the standard for synthetic resin emulsion coatings for interior wall. And also, the killing rate to Staphylococcus aureus and Escherichia coli reached 99.99% in 24 hours, its de-formaldehyde rate was 98.25%. To some extent, the coating can adjust air humidity.