Synthesis And Properties Of Photochromic Fluorescent Photoswitching Based On Naphthopyran

Naphthopyrans attract much attention because of their numerous potentialperformance, such as ultra high-optical-density for information storage, fatigueresistance and large capacity, etc. The photochromic naphthopyrans can be used tomodulate the fluorescent switch between “ON” and “OFF”. The photoswitchablefluorescent device based on naphthopyrans is fabricated, in which photochromiccompound match fluorescent dye. photochromic photoswitchable fluorescent whichcan express the photochromic properties and fluorescence properties, Fluorescenceintensity can be adjusted by photochromic properties is prepared by photochromicgroups and fluorescent groups through the way of formation of micromolecules,polymers, or doped.In this dissertation, the modulation of a fluorescence based on a controllablephotochromic naphthopyran was fabricated. First the photochromic copolymer wassynthesized using naphthopyran monomer and fluorescent monomer by atomtransfer radical polymerization. The photoswitchable fluorescent devices based onnaphthopyrans were investigated in solution and films. The fluorescent intensity canbe tuned reversibly by alternative irradiation with ultraviolet and thermal effect indark.Second the naphthopyran molecules and the fluorescent units can be connectedin a molecule by covalent bond, and to study the effect of photochromic behaviorson fluorescence. In both means the fluorescent intensitie was modulated by thephotoisomerization of photochorimc naphthopyran. However, in solutionphotoswitchable fluorescent device by polymerization mode have advantages, suchas better fatigue resistance, larger change of fluorescent intensity and more quickfluorescence quenching. This approach making fluorescent switching is easy,efficient and of high feasibility.