The Synthesis, Studies Of Electrochromic, And Photoresponsive Properties About Ester Of Azobenzene

The photoreponsive materials based on azobenzenen are extensively researched in the field of materials. In this thesis, a series of new azobenzene esters were synthesized and characterized. The electrochromic and photoresponsive properties of these azobenzene compounds were investigated. The specific research contents are described as follows:In Chapter One, firstly, the type and function of color materials were outlined. The relationship between color materials and the life was introduced, and the research progress and the practical applications of electrochromic materials were summarized. The electrochromic device (ECD) structure and the fabrication method were briefly described. Secondly, the classification of electrochromic materials were outlined. The research progress of organic electrochromic materials which contain ester groups was summarized. Finally, the research purpose and significance of this thesis were proposed.In Chapter Two, six azobenzene-4,4’-dicarboxylic acid dialkyl ester derivatives (ADDEDs) which contain two ester groups were successfully prepared by diazotization coupling reaction and esterification reaction using commercially available 4-nitrobenzoic acid,4-methoxy benzene methanol, and 4-trifluoromethyl benzene methanol as the raw materials, their chemical structures and molecular weights were characterized by 1H NMR,13C NMR, and LC-MS. The electrochromic properties of ADDEDs were studied, the results showed that these electrochromic materials have fast response time and good switching stability; the effect of substituent on electrochromic properties was also discussed. Afterwards, the photoisomerization of ADDEDs were studied in DMF solution and electrochromic conditions. The research suggests that the ADDEDs compounds have good electrochromic and photoisomerization properties.In Chapter Three, six azobenzene-3,3’-dicarboxylic acid dialkyl ester derivatives (ADADEs) which contain two ester groups were successfully prepared by diazotization coupling reaction and esterification reaction using commercially available 3-nitrobenzoic acid,4-methoxy benzene methanol, and 4-trifluoromethyl benzene methanol as the raw materials, their chemical structures and molecular weight were characterized by 1H NMR,13C NMR, and LC-MS. The electrochromic properties of ADADEs were studied, and the effect of substituents on electrochromic properties was also discussed. The electrochromic properties of ADADEs were compared with that of ADDEDS, the results demonstrated that ADDEDs compounds have excellent electrochromic properties. The possible reason is that the ADDEDs compounds have higher electron-density after the formation of anion radicals via redox reaction. Finally, the photoisomerization of ADADEs compounds in both DMF solution and electrochromic conditions were studied. The results suggest that the ADADEs compounds have good photoisomerization properties.In Chapter Four, six azobenzene-3,3’,5,5’-tetracarboxylic acid four alkyl ester derivatives (ATAFAEDs) which contain four ester groups were successfully prepared by diazotization coupling reaction and esterification reaction using commercially available 3,5-dinitrobenzoic acid,4-methoxy benzene methanol, and 4-trifluoromethyl benzene methanol as the starting materials. Their chemical structures and molecular weights were characterized by 1H NMR,13C NMR, and LC-MS. The electrochromic properties of ATAFAEDs were studied, and the effect of substituent on electrochromic properties was also discussed, the results showed that the electrochromic materials have fast response time and good switching stability. In comparison with ADADEs and ADDEDs, the ATAFAEDs compounds have excellent electrochromic properties than ADADEs, but lower than ADDEDs. Finally, the photoisomerization of ATAFAEDs compounds in DMF solution and electrochromic conditions were studied. The results suggest that the ATAFAEDs compounds have good photoisomerization properties.In Chapter Five, four (E)-1-benzyl-4-((4-(methacryloyloxy)phenyl)diazenyl)pyrid-in-1-ium bromide (EAZOPs) compounds which contain ester groups and pyridine were successfully prepared by diazotization coupling reaction and esterification reaction using commercially available 4-aminopyridine, phenol, methacrylic acid, and 4-trifluorine methyl benzoic acid as the starting materials. Their chemical structures and molecular weights were characterized by 1H NMR,13C NMR, and LC-MS. The electrochromic properties of EAZOPs were studied, and the effect of substituent on electrochromic properties were also discussed. In comparison with ADADEs, ADDEDs, and ATAFAEDs, the electrochromic properties of EAZOPs compounds don’t have great improvement.In Chapter Six, four vinylazopyridinium derivatives (AZOPs) compounds which contain different anions were successfully prepared by diazotization coupling reaction and the anion exchange reaction using commercially available 4-aminopyridine, phenol, benzyl bromide, lithium bis(oxalate)borate, and ammonium hexafluorophosphate as the raw materials. Their chemical structures and molecular weights were characterized by 1H NMR,13C NMR, and LC-MS. The electrochromic properties of AZOPs were studied, and the effect of anions on electrochromic properties were also discussed. In comparison with EAZOPs, the stability of AZOPs compounds have obvious enhancement.In Chapter Seven, the main results and conclusions of this full thesis were summarized, and some recommendations for future work in this field were proposed.