초록 |
A new donor-acceptor conjugated polymer (PBDT-DFBI), which consists of difluoro-alkyl benzoimidazole electron-acceptor unit and an electron-donor segment of alkoxyl substituted benzo[1,2-b:4,5-b']dithiophene (PBDT), was synthesized according to palladium catalyzed the Stille coupling reaction. The resulting copolymer was characterized by TGA, GPC, UV-vis absorption spectroscopy and cyclic voltammetry measurements. PBDT-DFBI good thermal stability and poor solubility in common types of organic solvents. The polymer based on benzoimidazole units show λmax at 365 ~ 508 nm. With a highest occupied molecular orbital (HOMO) energy level around -5.20 eV, these polymers exhibit a narrow bandgap of 1.75 ~ 1.87 eV. |