Study On The High Refractive Glass Beads By Sol-gel Technique

High refractive index glass beads with good regression reflection characteristics have been widely used for port traffic signs, petroleum, chemical industry, water purification and the film of advertising. In order to overcome the shortcomings of traditional methods,such as high energy consumption and low yield.This paper has prepared high index beadsby sol-gel,and studied the preparation process and the impact on its performance.In this paper, the SiO2-TiO2 and SiO2-TiO2-ZrO2 system as to the main component of high refractive index glass beads.Mixed sol were preparedfirstly,the main influencing factors of the sol-gel process were studied by the contrast test.The optimum conditions are described as follow:the best molar ratio is C2H5OH: Ti(OBu)4= 2:5; H2O: TEOS= 5:1;H2O:Ti(OBu)4=8:1, pH value at 3.0.The sol were dispersed in the oil phase and formed the sol beads by surface tension which is the method of emulsion. After drying and sintering they became glass beads.Thedispersed degree and gel time of beads were controlled by adjusting the emulsifier content and temperature.Adjusting the sintering system was able to control the density, strength, light transmittance and roundnessof beads.The beads with good roundness which pearl formation rate reached more than 80%, and refractive index reached about 1.9 were prepared in the optimal preparation conditions.The use of XRD, SEM, polarizing microscope and differential thermal analysis, and other means of refraction of glass bead rate, microstructure, particle size distribution,reflective performance were characterized.The properties of glass beads were characterized by polarizing microscope XRD, SEM,and differential thermal analysis method, such as refractive index, microstructure, particle size distribution and reflecting degree etc.