Investigation On Preparation And Properties Of The Nanometer UV Irradiation Shield Transparent Coatings

Because of its special characters, nano-technology has been a field of growing interest in recent years. The nano-composite coatings have many functions and high performance can be manufactured by putting appropriate nano-particles into polymer and they can be applied to many fields. In this paper, dispersion of nano-particles in water was mainly investigated, and ultraviolet (UV) radiation shield transparent nano-coatings were prepared, their performances were tested.Such factors as category and content of dispersant, pH, disperse manner, disperse time and particle content, has effect on the stability of the dispersion. The stability of dispersion has been in token of spectrophotometer and laser particle-sizer. It is proved that when condition is dispersant A =1.5%, pH =10.4, particle content = 2%(Wt%), mixing around under high speed for two hours, excellent stable nano-SiO2 aqueous dispersion can be acquired.Solvent-based UV irradiation shield transparent nano-coatings were prepared by using nano-SiO2, nano-ZnO and nano-Fe2O3. The effect of nano-particles content on the UV-VIS spectrum, viscosity, hardness and other applied performance of the coatings we prepared were discussed, and compatibility and dispersity of nano-SiO2 in different resin system were also discussed Solvent-based UV irradiation shield transparent nano-coatings with high UV shield and excellent transparent using different resins were prepared. When the particle content of nano-SiO2 is 2Wt%(namely pigment binder ratio is 1:19.4), UV shield rate of coat within wave length 200nm~400nm is average 51.3%, even arriving at average 83.6% within wave length 200nm~300nm, and its VIS transmission is average 93.8%. Particles size of nano-SiO2 in coat is mainly within 40nm-60nm testing by TEM photo, and the basic performance of this kind of Solvent-based UV irradiation shield transparent nano-coatings accorded with or excel correlative national standard. It can be used as covering varnish.Preparation of green UV irradiation shield transparent nano-coatings and itsperformance have also been tried. We mixed nano-SiO2 with aqueous PU resin or mellow silicone acrylate resin, or we used in situ polymerization of organosilicone resin by silane coupling agent KH-570 in existence of nano- SiO2, to prepare green UV irradiation shield transparent nano-coatings. And we tested the UV-VIS spectrum and other basic technology performance. We can conclude by testing that the nano-coatings we prepared have high UV shield and excellent transparent, and other performance is also good.