Coumarins Labeled Water-soluble Fluorescent Monomer Synthesis And Characterization

The structure of fluorescence-lablelled water treatment agent with fluorophore, which can be detected rapidly and accurately by fluorescence examination. We can achieve continuous on-time monitoring and real time control of the circulation cooling water by combining fluorescent tracer technique and automated technique. It is very economic and social values that synthesis such monomer including both unsaturated double bond and fluorescence characteristic that can be mixed with water treatment agent or be copolymerized with another monomer in the application of the water treatment agent.A kind of water-soluble fluorecent monomer was synthesized from resorcinol and ethyl acetoacetate via Pechamnn reaction, esterification, substitution reaction and quaternaristion. That is a quaternary ammonium salt of dimethylanminopropyl methacrylamide (DMAPMA) and 4-(bromomethyl)-7-acetoxycoumarin (Br-MAC). The structure of fluorescent monomer and its intermediate compound were characterized by FT-IR and NMR. In addition, the heat stability of these compounds were analyzed by TG and DTA. The optimum reaction conditions of the 7-hydroxy-4-methyl coumarin and 7-acetoxy-4-methyl coumarin were obtained by improved synthesis process. 3,6,8-tribromo-4-methyl-7-hydroxy coumarin was also synthesized. Its crystal structure was determined by Bruker-P4 diffractometer. Fluorescence properties of the monomer were studied by fluorescence spectrum and UV spectrum. The monomer has stronger fluorescence properties. The excited and the emitted wavelength of the monomer is 372 nm and 412 nm, respectively. The change tendency of UV absorption intensity of the monomer was under different concentration. The relationship of linearity betwin the UV absorption intensity and concentration is well. The bactericide efficiency of the fluorescent monomer were studied. The results showed that the fluorescent monomer had great bactericide performance within certain concentration range. So, the monomer can be well used in the system of industrial circulation cooling water treatment.