Synthesis and Characterization of Four Random copolymers Containing Fluorene as Electron Donors and Benzotriazole, Benzothiadiazole, Pyrido[3,4-b]pyrazine as Electron Acceptors

摘要

Four copolymers, poly(fluorene-pyrido[3,4-b]pyrazine) (PFPP), poly(benzotriazole-fluorenepyrido[3,4-b]pyrazine) (PBTFPP), poly(benzotriazole-fluorene-benzothiadiazole) (PBTFBD),poly(benzothiadiazole-fluorene-benzothiadiazole) (PBDFBD)were synthesized successfully.Afterwards, a series of characterization, including cyclic voltammetry (CV), spectroelectrochemistry,kinetics, colorimetry and thermal gravimetric analysis were carried out to fully investigate the propertiesof the copolymers we got. Their band gaps are 1.87 eV, 1.91 eV, 1.97 eV and 1.98 eV, respectively.From neutral state to oxidized state, PFPP changes from thistle to transparent gray, PBTFPP changesfrom tan to transparent gray, PBTFBD changes from sienna to lightslategray, and PBDFBD changesfrom rosybrown to lightgrey. The coloration efficiencies are 269.91cm2·C-1 for PFPP, 177.45cm2·C-1forPBTFPP, 241.92cm2·C-1 for PBTFBD, and 174.67cm2·C-1 for PBDFBD in near infrared region.Except for PFPP, all the other three copolymers are stable and could be good candidates inelectrochromic application.