Research On The Dispersion Of Tourmaline/TiO₂ Composite In Aqueous Media And Its Application

Tourmaline/ TiO₂ composite is a kind of compound powder material that the tourmaline is covered by TiO₂. With releasing the negative ions and the far infrared, tourmaline/ TiO₂ composite increases tourmaline's white degree and append its pigment function with a layer TiO₂ on surface. It is concluded that tourmaline/ TiO₂ composite is an outstanding environment functional material. The studying of the basic problem on the dispersion of tourmaline/TiO₂ composite in medium, that can provide direction and the basis for compounding with architectural decoration material, such as the wooden floor board, and it also has a very important effect on stretching the application range of tourmaline/TiO₂ composite and its air purifying. In a word, studying application of the dispersion of tourmaline/TiO₂ composite, which has a pushing effect on both indoor environment and architecture decorate material decorative materials with the function of air-purifying.Dispersions of tourmaline/TiO₂ composite in aqueous media and melamine-formaldehyde resin adhesive were studied in the thesis with extended DLVO theory. The dispersion state of tourmaline/TiO₂ composite in melamine-formaldehyde resin adhesive was characterized by the analyzing of scanning electron micrographs (SEM).By testing the dispersion and agglomeration behavior, the effects of different pH value, different dispersant on tourmaline/TiO₂ composite in aqueous media were investigated. The experiment results indicated: Both of higher and lower pH values are able to improve its dispersion stability in aqueous media; Sodium hexa metaphosphate, sodium silicate and sodium polyacrylate had the very good dispersing effects. Under sodium hexa metaphosphate condition, the partial diameters of this composite have gotten smaller to 0.37μm than primitive grain diameters to 0.81μm. The optimal addition of sodium hexa metaphosphate is 0.36%～0.4%. Polyvinyl alcohol, sodium dodecyl benzene sulfonate, polyacrylamide (PAM), polyethylene glycol can not improve the dispersion effect.By analyzing the effect of sodium hexa metaphosphate to tourmaline/TiO₂ composite, this paper deems the adsorption of sodium hexa metaphosphate on the surface ofTiO₂ component and the forming of hydration shell can improve dispersion. Then a series of experiments on tourmaline/TiO₂ composite in melamine resin glue were made. By analyzing TEM and the testing of compound performance, the results indicate, that sodium hexa metaphosphate can remarkably improve the dispersion and stability of tourmaline/TiO₂ composite and increase the release of negative ions. the function of compound wooden floor board prepared with tourmaline/TiO₂ composite keeps its appearance and performance invariable. The number of releasing negative ions has reached 1200～1600 /cm3.