Preparation And Characterization Of TiO₂/Illite Compound UV Shielding Material

Recently,increasing problems of ultraviolet light caused by the destruction of the ozone layer have attracted more and more attention.In order to prevent the ultraviolet light,people begin to develop new types of UV shielding materials.Because of the semiconductor property and nanoscale grain size,TiO₂ presents excellent abilities of absorbing and scattering the UV light.However,the poor dispersity,high photocatalytic activity and poor film forming property of TiO₂ restrict its application in the UV shielding field.To solve this problem,one effective way is using the carrier to load TiO₂.This experiment selected illite as carrier,Ti?SO₄?₂ and TiCl₃ as titanium sources,and prepared TiO₂/illite composites with different crystal types.The phase analysis and performance tests were carried out respectively.Firstly,anatase TiO₂/illite composites were synthesized by hydrothermal method using purified illite and Ti?SO₄?₂ as raw materials.The effects of hydrothermal conditions and TiO₂ contents on the phase structure,micromorphology and UV shielding properties of the composites were investigated by various characterization methods.The results show that when the pH value of the initial reaction system is 4,the hydrothermal temperature is 180^oC and the hydrothermal time is 12 h,the anatase TiO₂/illite composite has good crystallinity and excellent UV shielding performance.The UV shielding abilities of composites are enhanced with increasing TiO₂ contents,and the PIT-50%exhibits the best UV shielding performance which can block almost100%of UVC,over 98%of UVB and nearly 60%of UVA.In addition,the mechanical properties test results also show that the PIT-50%@fabrics present the best UV resistance ability,the breaking strength retention rate can reach 71.4%after 8h of UV irradiation.The rutile TiO₂ was prepared by hydrothermal method using TiCl₃ and NaNO₃,and the effects of hydrothermal conditions on structure,micromorphology and UV shielding performance of TiO₂ were studied in detail.The results show that the best hydrothermal conditions are:the concentration of NaNO₃ is 0.01 mol/L,the hydrothermal temperature is 200^oC and the hydrothermal time is 2 h.On this basis,the rutile TiO₂/illite composites were synthesized by adding illite.The addition of illite improves the dispersity of TiO₂,but also leads to the appearance of anatase in the composites.Further research proves that the rutile TiO₂/illite composite exhibits the best UV shielding performance except for the blank TiO₂ when the load ratio is 1:1.Meanwhile,the corresponding coated fabrics present good UV resistance ability,which can maintain 65.1%tensile strength after UV aging test.