| Organic photochromic materials have man y characteristics, such as fresh color and quick and reversible color change. But the property of color change is apt to be destroyed after photochromic materials were affected by solvent, acid, alkali, oxygen, high temperature and other environmental factors. It was the primary aim that how to avoid the influence of environmental factors during preparing on photochromic composite materials.Porous crosslink polystyrene microspheres were produced by dispersion polymerization in this paper. The prepared process of microspheres and properties of loading photochromic materials were studied in detail. Polystyrene microspheres were made using St as monomer, PVP as stabilizer, anhydrous alcohol/deionized water as the dispersion medium, AIBN as initiator, the DVB as crosslinking agent and toluene/heptane as mixed porous agent. Spiropyran and spirooxazines was used as photochromic materials. The influences on average size and size distribution were investigated, such as polymeric monomer, stabilizer, dispersion medium, initiator, porous agent. These factors affected the porosity and photochromic materials adsorption of microspheres too. The SEM, particle size analyzer and TG instrument were used to analyzed morphology, particle size and thermal stability. Microspheres coating with PVA was carried for increasing the color change stability. The most important factor affected the adsorption amount of photochromic materials was the amount and composing of porous agent. The equilibrium adsorption amount and adsorbent velocity on photochromic materials of porous microspheres increased with the primary concentration increase of photochromic materials and adsorbent temperature. The anti-UV property was improved photochromic microspheres after microspheres were coated with PVA.Photochromic microsphered obtained in this paper could carry quick and reversible color change in sun-light or UV and this color change could persist for long time and many times.
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