Study On The Synthesis And Property Of Azobenzene-Containing Ferrocenyl Compounds And Polymers

It is believed that anion is of great importance because of their close relationship with environment and people’s health. For example, the high concentration of fluoride (F-) and dihydrogen phosphate (H2PO4-) may cause environment pullution and various diseases. Therefore, it is very important to design materials that can effectively recognize specific anions. Anion recognition material is usually composed of two parts, which are the combination unit and the signal unit. The combination unit is mainly used for the combination of anions, while the signal unit is used to transmit the binding information through a certain way. Among all of the signal units, electrical signal and optical signal units are the most widely used and the most convenient signal units. Electrical signals can be detected by electrochemical methods such as cyclic voltammetry (CV). The optical signal can be detected by the naked eyes, ultraviolet fluorescence detector (UV-vis) and so on. In addition, sensing materials with multiple signal elements can be used in different detection methods, which makes the detection process more flexible and reliable.Several anion sensing materials containing ferrocene and azobenzene were synthesized in this thesis. The electro-and photo-chemical properties and anion recognition ability of the prepared compounds and polymers were studiedd. The contents include the following three parts:(1) Study on synthesis and properties of azobenzene-containing ferrocenyl compoundsThree azobenzene-containing ferrocenyl compounds were synthesized by acylation reaction. The structures were characterized by 1H NMR, 13C-NMR and infrared spectroscopy (FT-IR). Their thermal stability was studied by TG and it was found that the substituent will affect the thermal stability. Their electro- and photo-responsive properties and anion recognition performance of the synthesized compounds were studied through CV and UV-vis methods, respectively. The smaller solvent polarity and lower scanning rate resulted the better reversibility of the CV curves. In addition, the three compounds will be isomerized between trans-and cis-state under irradiation of UV and vis lights respectively. Through anion recognition tests, it was found that Fcazol and Fcazo3 with nitro substituted groups had selective anion recognition for F- and H2PO4-, while the amino substituted Fcazo2 showed little sensitivity to anions. This may be due to the nitro group, which is an electron withdrawing group, makes the compounds possibly to form hydrogen bonds with specific anions, while the amino group is an electron donating group, which reduced the interaction between amide group and anions and weakened its anion recognition performance.(2) Study on synthesis and properties of azobenzene-containing ferrocenyl graft polymersPGMA was synthesized by the free radical polymerization of GMA. And then it was reacted with Fcazo2, p-hydroxyazobenzene and carboxyferrocene by ring opening reaction to form polymers containing azobenzene and/or ferrocene groups in the side chain. The chemical structures of the four polymers were characterized by 1H-NMR and FT-IR. The molecular weight and its distribution of the polymer was investigated by GPC. TG was employed to study the thermal stability of the polymers. CV and UV-vis were used to study their electro- and photo-responsive properties and anion recognition performance. It was found that PGMA-Fc and PGMA-Fcazo have good electrochemical properties, while PGMA-Azo and PGMA-Fcazo show good optical responsive behavior. Besides, it was found that PGMA-Fcazo showed good selectivity for F-, which can be used for anion recognition.(3) Study on synthesis and properties of azobenzene-containing ferrocenyl copolymersMAFcAzo, MAazo and FcEMA were synthesized by condensation reaction method. They were copolymerized with MMA to prepare P(MAFcazo-co-MMA), P(FcEMA-co-MAazo), P(MAazo-co-MMA) and P(FcEMA-co-MMA). The chemical structure was characterized by 1H-NMR and FT-IR. The polymers were thermal stable below 200℃. The properties and anion recognition performance of the synthesized compounds and polymers were studied by CV and UV-vis methods. MAFcazo, P(MAazo-co-MMA), P(MAFcazo-co-MMA), P(FcEMA-co-MAazo) and MAazo showed benign photo-responsive characteristics. FcEMA, P(FcEMA-co-MMA), MAFcazo, P(MAFcazo-co-MMA) and P(FcEMA-co-MAazo) have good electrochemical properties. CV curves and UV visible absorption spectra showed that MAFcazo and P(MAFcazo-co-MMA) with amide groups are selective for F".