Synthesis,Properties Studies Of Anthracene-Based Photosensitizers And Its Appilication In Photopolymerization

Anthracene and its derivatives can be either used as highly efficient photosensitizers in photopolymerization or as catalysts to regulate atom transfer radical polymerization.In this thesis,a series of anthracene-based photosensitizers were synthesized.Their photophysical properties and electrochemical properties were investigated by experiments and calculations,their application in photopolymerization were discussed,the corresponding structure-property relationships were established.To study the effect of substitution group on sensitizing ability,four monosubstituted anthracene derivatives(SubAN)were synthesized.They are anthracene-9-carbaldehyde(ANCHO),3-(anthracen-9-yl)-2-cyanoacrylic acid(ANCA),9-nitroanthracene(ANN02),and 4-(anthracen-9-yl)morpholine(ANMP),respectively.The characterization results show that the SubAN has only weak absorption at visible light regions,and the electron withdrawing group increases the molecular oxidation potential.Under the 385 nm light source,the initiating activity of ANMP/ONI in SubAN/ONI system is better than that of anthracene/ONI.ANCHO and ANCA cannot sensitize ONI.Photopolymerization results demonstrate that the introduction of electron-withdrawing groups is not conducive to the sensitization process of compounds to ONI.In order to prolong the absorption wavelength of anthracene-based molecules and reduce their oxidation potential,phenyl,carbazole,triphenylamine,and phenothiazine electron donor units were bridged to the anthracene core to synthesize four conjugated alkynyl anthracene compounds.(ANDs).They are 9,10-Bis(phenylethynyl)anthracene(A1),9,10-Bis((9-dodecyl-9H-carbazol-3-yl)ethynyl)anthracene,9,10-Bis((10-dodecyl-10H-phenothiazin-3-yl)ethynyl)anthracene(A3),and 4,4'-(Anthracene-9,10-diylbis(ethyne-2,1-diyl))bis(N,N-diphenylaniline)(A4).ANDs has strong absorption in the blue-green region,and also has a large two-photon absorption cross section at 780 nm-880 nm,and its oxidation potential is significantly lower than that of antnracene.The ANDs/ONI system is capable of efficiently initiating HDDApolymerization at 455 nm and 520 nm LEDs,which is superior to the commercial CQ/TEOA system under the same conditions.Photopolymerization results show that ANDs are highly-efficient visible light photosensitizers.Under the household 7 W energy-saving lamp,ANDs can mediate the atom transfer radical polymerization of methyl methacrylate.The obtained polymethyl methacrylate has a molecular weight of between 12 K and 14 K and a dispersity of between 1.2 and 1.3,exhibiting a controllable characteristic.