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In this thesis, using the electron donor - acceptor alternating copolymerization strategy selection 3,4 - ethylenedioxy thiophene (EDOT) as an electron donor unit, 1,4,5,8 - naphthalene diimide ( NBI) derivatives as electron acceptor unit, Stille coupling polymerization method selected, designed and successfully synthesized a lower band-gap alternating copolymer P1. Wherein a major monomer successfully synthesized 2,5 - bis (tributyltin) -3,4 - ethylenedioxy-thiophene (2) and solve the problem of its purification is difficult to complete the 1,4,5,8 - naphthalene tetracarboxylic dianhydride (NBA) bromination and amidation reactions, and Stille coupling two polymerization of monomers, and finally get a target molecular weight copolymers of moderate P1; successfully synthesized a vinyl monomer, 2 - Tributyltin -3 4 - B dioxythiophene (1), and achieved its electron acceptor unit with coupling reaction, get trimer bis-EDOT-NBI; use of 1H NMR, 13C NMR, MS and elemental analysis intermediates monomer, trimer, and copolymers made to characterize the structure of P1, that to obtain the target compound, and high purity. Ultraviolet absorption spectrum shows trimer bis-EDOT-NBI at the maximum absorption peak of 540 nm, the initial position estimation by absorbing the optical energy band gap of 1.99 eV. The copolymers P1, thermal properties, optical properties and electrical properties make a characterization, TGA tests show that the thermal decomposition temperature Td was 440 ℃, show that the material has good thermal stability; solution show the UV absorption spectra from 400 to 750 nm absorption between a larger, solid UV absorption by the initial position estimation of the optical energy band gap of 1.75 eV, are areas of low-energy band gap; cyclic voltammograms obtained the electron affinity EA (LUMO level) of the value 3.90 eV, ionic potential Ip (HOMO energy level) is 5.65 eV, the higher are the same polymer. The copolymer lower optical bandgap and broader spectral absorption inferred from the solar cell materials and other optoelectronic devices has great application prospects. The second part of this thesis work in the previous step, based on the successful synthesis of important monomer 2,5 - dibromo 3,4 - ethylenedioxy thiophene (6) and participation copolymerization, polymerization by Stille coupling prepared a random copolymer P2. And using 1H NMR, 13C NMR and elemental analysis were characterized prove objectives copolymer product P2 obtained high purity, its molecular weight by GPC analysis. Random copolymer P2 on thermal properties, optical properties and electrical properties were characterized do. Thermal decomposition temperature Td was 420 ℃, show that the material has good thermal stability; solution UV absorption spectra at 500 to 900 nm between the absorption of a larger, solid film by UV absorption of the optical energy starting position estimation band gap of 1.38 eV, belonging to low-energy band gap areas; cyclic voltammetry curves obtained its electron affinity EA (LUMO energy level) is 3.84 eV, ionic potential Ip (HOMO energy level) is 5.22 eV, are similar polymerization matter whichever is higher. The copolymer is lower than the optical energy band gap and the broad spectral absorption speculated that the solar cell material, and other optoelectronic devices has great prospects. Further, experimental verification of the monomer (6) solid state polymerization phenomenon was blue-black conducting polymer poly (3,4 - ethylenedioxythiophene thiophene) (PEDOT).
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