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Organic photochromic material has discolored sensitive, bright color, but are vulnerable to environmental factors such as temperature, light, pH, and oxygen cause oxidative deterioration, poor fatigue resistance. How to avoid the impact of environmental factors discoloration performance composites process photochromic, is the main objective of this study. To diversify polymerization of porous cross-linked polymer microspheres research microsphere preparation process and load performance of the photochromic material. Experiment styrene as a monomer, polyvinyl pyrrolidone as stabilizer, anhydrous ethanol / deionized water mixture as a dispersion medium, azobisisobutyronitrile initiator, divinyl benzene as crosslinking agent, a toluene / hept alkyl-mixed solution as porogen, porous crosslinked polystyrene microspheres by dispersion polymerization. To use the spiropyran spirooxazine Two photochromic materials. Detailed study of the porogen, polymerizable monomer, initiator, stabilizer, etc., the amount of the microspheres have an average particle size, particle size distribution, porosity and light induced by the influence of the adsorption properties of the photochromic material, the concentration of the photochromic material also studied adsorption temperature on the amount of adsorption. Experimental Morphology and dispersion of the microspheres through the scanning electron microscope, using a laser particle size analyzer measuring average particle diameter and particle size distribution of the microspheres and analyzed by the thermal stability of the microspheres by thermal gravimetric analysis. In order to improve the adaptability of the the photochromic microspheres application environment, also studied the surface coating on the microspheres photochromic properties. The experimental results show that the porous cross-linked polymer microspheres prepared in the optimum process parameters, good sphericity, smooth surface, the microspheres having a uniform particle size and good dispersion, the average particle diameter of the polymer microspheres in about 1μm. Crosslinker DVB added, is conducive to improve the thermal stability of the microspheres. The to porogen, polymerizable monomer, initiator, stabilizer adsorbed on microspheres affect the adsorption amount of the photochromic material, wherein the porogen and the greatest impact. The initial concentration of the solution of the photochromic material is the greater, the greater the amount of adsorption of the adsorption equilibrium microspheres; higher adsorption temperature, microspheres light Rev. faster adsorption rate of the photochromic materials, the higher the equilibrium adsorption capacity. After the adsorption of the surface of the microspheres after the photochromic material coated PVA improve the performance photochromic microspheres UV aging resistance. The photochromic microspheres prepared in this paper, ultraviolet light or sunlight, has a the fast reversible photochromic performance discoloration more durable performance.
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