Preparation And Characterization Of TiO₂/Illite Composite Ultraviolet Shielding Material Based On Crystal Form Control

Ultraviolet rays have a great impact on human health and social environment,so the preparation of new ultraviolet shielding agents is very important.TiO₂ itself has high whiteness,narrow band gap,and high specific surface area.It has excellent light absorption and scattering characteristics,and is an efficient ultraviolet shielding agent.However,TiO₂ has poor dispersibility and high photocatalytic activity,which also makes TiO₂ difficult to protect from ultraviolet rays in practical applications.TiO₂ has three different crystal types,among which rutile TiO₂ has the characteristics of narrow band gap and high refractive index,and shows excellent performance in ultraviolet shielding.The anatase TiO₂ has a relatively low refractive index,which makes it show relatively poor UV shielding performance,and the brookite TiO₂belongs to the unstable phase,and there are relatively few studies on this crystal form.This article focuses on the influence of crystalline form on TiO₂ and composite TiO₂UV shielding agents.Two different precursors of tetrabutyl titanate and tetraethyl titanate were used to prepare illite-loaded TiO₂ composite materials to obtain Composite materials with excellent UV shielding properties.First of all,we used tetraethyl titanate as the titanium source and prepared a single crystal TiO₂ composite material with illite loaded by hydrothermal method,and analyzed the effect of different hydrothermal conditions on the crystal form and morphology of the composite material and the ultraviolet shielding performance.On the difference.The experimental results show that the rutile TiO₂ nanorods prepared at hydrothermal temperature 180℃,time 12 h and pH value 6 have the best aspect ratio and show the best ultraviolet shielding performance,which can almost shield 100%of UVC,UVB and 85%of UVA.The analysis of the composite material found that illite can improve the ultraviolet shielding effect of TiO₂ nanorods.The composite material of illite loaded rutile TiO₂ nanorods shows the best ultraviolet shielding performance when the loading ratio reaches1:1,which is almost It achieves the same UV shielding effect as TiO₂ of the same quality,and can shield nearly 100%of UVC,UVB and 90%of UVA.In practical applications,this coating can protect cotton fabrics from UV damage.The mechanical test results show that the cotton fabric coated with the compound with the loading ratio of 1:1 keeps the tensile strength at 76.8%after 8hours of ultraviolet light,which obviously improves its tensile strength and alleviates the damage caused by ultraviolet rays to cotton fabrics.After that,we used tetrabutyl titanate as the titanium source and prepared the illite-loaded anatase/brookite complex TiO₂ composite material by hydrothermal method.The effects of different TiO₂ crystal ratios and morphologies on the TiO₂ UV shielding performance,as well as the effects of the load ratio and load state on the composite UV shielding performance are analyzed.The experimental results show that the complex phase TiO₂ prepared under the hydrothermal conditions of hydrothermal temperature 180℃,time 24 h,and crystal guide agent NaCl solution concentration of1mol/L has the best ultraviolet shielding performance,and anatase accounts for about70%,brookite accounts for about 30%.Subsequently,we loaded titanium dioxide of different qualities onto the surface of the illite sheet.The results showed that the composite showed the best UV shielding performance when the loading ratio reached1:1.The resulting composite not only achieved low cost but also achieved practical application.It has wider practicality.