Synthesis And Characterization Of Benzotriazole-Containing π Conjugated Polymers

π-conjugated polymers are attracting much attention due to their interestingelectronic and optical properties.donor–acceptor (D–A) type conjugated polymersconsisting of electron rich and electron deficient units have aroused a great attentionafter their discovery because these materials are potentially useful for manyapplications especially in solar cells, LED's, electrochromic devices and sensors.Benzotriazole (BTz) is a typical electron deficient compound, bringing electronwithdrawing unit benzotriazole (BTz) on electron releasing backbone willconsequently decrease the band gap of the molecule.New π-conjugated polymerscontaining benzotriazole group have been synthesized by Pd(II) complex catalyzedsonagashira reaction.The chemical structure of these polymers were characterized by1H-NMR, FT-IR. The basic properties including UV-Vis,PL,CV have also beenresearched.The number average molecular weight of these polymers lie in the area of0.28×10⁴¹.13×10⁴. Poly (aryleneethynylene) derivatives containing benzotriazolegroup and bearing side chains of different lengths exhibit higher fluorescencequantum yield in CHCl₃solution,good solubility in common organic solvents such asCHCl₃,tolune,and it is easier to prepare the film of these polymers.Among thesepolmers, P-8and P-12show better solubility in common organic solvents than P-4. Itcan be known from the basic fuctional test that the maximum absorbance of thesepolymers in cast film had red-shifted45nm from than in CHCl₃solution. Theemission peaks of these polymers in cast film had red-shifted60nm from than inCHCl₃solution. Benzotriazole and3-alkylthiophene (3T) bearing polymers P3BTBT,P3OTBT and P3DTBT exhibit lower fluorescence quantum yield in CHCl₃solution,good solubility in common organic solvents such as CHCl₃,THF,and it iseasier to prepare the film of these polymers,These polymers have good thermal stability. Benzotriazole and EDOT bearing polymer PEBT exhibits good solubility incommon organic solvents such as CHCl₃,DMF,but it is hard to prepare the film of thepolymer.It shows good CV stability.