Study on the Preparation and Properties of Mg（OH）₂/TiO₂ Antimicrobial Flame-retardant Composite

Titanium dioxide （TiO₂） doped with nitrogen and tungsten,having a high photocatalysis performance,was prepared by sol-gel method with tetra-n-butyl titanate as raw material. Magnesium hydroxide （Mg（OH）₂）-titanium oxide composite materials were obtained by bubbling ammonia in mixture of the prepared TiO₂ and magnesium chloride （MgCl₂） solution,then heating and stirring. Employing XRD,SEM,XPS and FT-IR,the properties of the Mg（OH）₂/ TiO₂ composite were investigated. The results show that the size distributional width of the composite is 5.5200 μm and D₅₀ is 7.1800 μm. The composite is well dispersed and has a regular morphology,with tiny spherical TiO₂ particles adhered on the surface of the hexagonal flake powder. The spherical particles adhered on Mg（OH）₂ powder are anatase TiO₂,and there exists Mg-O-Ti chemical bonding between Mg（OH）₂ and TiO₂ in the composite. The weight loss of the composite is 24.5% under 300~400 ℃ with 387.1 ℃ of strongest endothermic temperature,meeting the requirements of Mg（OH）₂ flame retardant. The antibacterial properties of the composite were also tested by shake flask method,and the sterilization rate for coli can reach to 83.7% in 120 min.