Synthesis And Characterization Of Water-Soluble Conjugated Polymer Containing Fluorene Units

Water-soluble conjugated polymer is introduced water-soluble side chain in theconjugated polymer main chain. This kind of polymers with excellent water solubility andphotoelectric properties. In recent years, chemo-and biosensors, light-emitting diode (PLEDs)and polymer thin film photovoltaic cells (PSCs) on the basis of the water-soluble conjugatedpolymer has obtained rapid development, showing a broad application prospect. Theadvantage of conjugated polymer optoelectronic materials is that their photoelectric propertiesare easily improved and adjusted through simple chemical modification (Such as theintroduction of specific functional groups), which can be accomplished that controlling theperformance of the device by chemical modification of polymer. Based on this kind of designthought, this paper synthesized a series of water-soluble conjugated polymers and theirproperties have been characterized.The paper is mainly to research the following two aspects:1.Synthesized of new RAFT(S-1-dodecyl-S′-(α, α′-dimethyl-α′′-acetic acid)threeglucosinolates carbonate)reagent containing tetraphenyl ethylene unit and its water-solubleconjugated polymers. Tetraphenyl ethylene unit is distorted nonplanar space structure, whichhas been confirmed that it has aggregation-induced emission (AIE), which is the importantstructure unit for the synthesis of AIE materials; Fluorene is a planar rigid structure unit, theintroduction of it can improve the thermal stability of compounds. By the method of synthesisof water-soluble conjugated polymer with strong aggregation-induced emission and goodthermal stability. Through the determination of polymer’s ultraviolet spectra and fluorescencespectrum in aqueous and THF solution under different concentrations, it can be seen that thepolymer in aqueous solution with strong aggregation-induced emission and the fluorescenceintensity in the aqueous solution is far stronger than its fluorescence intensity in THF solution;It can be seen that polymer has obvious weightlessness after350℃by the TGA curves, andthe thermal decomposition temperature of weight loss of5%is302℃, showing good thermalstability.2.The synthesis of water-soluble low band-gap conjugated polymers containing fluoreneunits. Polyfluorene usually has a larger band-gap (3.68eV), which is widely used as a lightemitting diode that is blue luminescent material. But we usually can introduce differentelectron donor and receptor cell in polymer skeleton to adjust optical band-gap of fluorene polymers.This paper is introducing4,7-2(5-iodine-2-thiophene)[2,1,3] benzodithiazole unitin the alkyl-fluorene polymer to adjust the optical band-gap of polymer, then grafting differentwater-soluble side chain in the main chain of polymer for synthesis of three different kinds ofwater-soluble low band-gap (2.01eV) conjugated polymers. The new polymers have redluminescent effect, through measuring the uv absorption spectrum and fluorescence emissionspectrum of aqueous solution to calculate the fluorescence quantum yield of three kinds ofpolymers are0.55、0.20、0.11.