Study On The Synthesis, Photochemistry Behavior Of Dongating Chromophore Unsaturated Monomers And Polymers

Charge transfer phenomenon has been attracted much attention due to its significance in academics and applications. So far, a series of vinylic monomers bearing electron-donating fluorophore moieties and their polymers were reported on their photochemical behaviour including fluorescence and photo-sensitizing behavior. It has been found that the fluorescence intensities of these monomers are always dramatically lower than those of their corresponding polymers or their saturated model compounds at the same chromophore concentration. Such a phenomenon is termed as fluorescence "Structural Self-Quenching Effect "(SSQE).These monomers can be photopolymerized, as well as be used initiate the photomerization of other monomers, which do not have chromophore moieties. A number of literatures reported the synthesized acrylic monomers bearing electron-donating chromophore moieties, in which the electron-donor and the electron-acceptor were connected in terms of saturated grease chains. But in the case of P -diketone-bridge instead of grease chains, what the characteristics of fluorescence are and whether SSQE occurs, is worth to study in detail. This dissertation deals with these problems.1)A P -diketone-bridged chromophore-containing acrylic monomer, 1 -(4-dimethylaminophenyl)-4-methyl-4-pentene-1,3 -diketon(DMPDK) and its saturated model compound were synthesized and investigated by spectroscopy. It was found that the fluorescence intensity of DMPDK is much lower than that of model compound(DMBDK) at the same concentration which indicates that DMPDK, a P -diketone-bridged acrylic monomer bearing chromophore moiety, also shows fluorescence structural self-quenching effect(SSQE). Photoinduced tautomerization of DMBDK in acetonitrile was studied by means of UV and fluorescence spectroscopy. The results is implied that fluorescence method is capable of monitoringtautomerization of some fluorescence P-diketone.2)In this section, the photopolymerization of methyl methacrylate initiated by 9-Vinylanthracene and diphenyldonium chloride salt has been studied, the photopolymerization rate equation and its activation energies were obtained:Rp[MMA]042[9-VAn]035[DPIOC]022 and Ea=28.7kJ/molThe result was compared with that of photopolymerization of MMA initiated by 9-Vinylanthracene alone, it was found that the former was higher than the latter. From the analysis of UV of polymer initiated by the above initiators, it is confirmed that they not only initiated the polymerization, but also entered into the polymer chains. 3)3-acrylamide-9-ethylcarbazole(AAECZ)was synthesized. The polymerization of methyl methacrylate initiated by 3-acrylamide-9-ethylcarbazole and diphenyliodonium chloride salt has been studied, the photopolymerization rate equation and its activation energies were obtained:Rp [DPIOC]020[AAECZ]?17[MMA]?80and Ea=28.8kJ/mol. The mechanism of initiation has been discussed.