| 초록 |
Condensation copolymerization reactions of carbazole 3,6-diboronate with DTBT only produce low molecular weight D-A copolymers. To elucidate the cause of the persistently low molecular weight, we synthesized three 3,6-carbazole-based D-A copolymers using 3,6-carbazole derivatives with DTBT and alkyl-substituted DTBT. We investigated several parameters for their influence on molecular copolymer weight. Low molecular weights of 3,6-carbazole-based D-A copolymers resulted from conjugation breaks which led to strong interactions between polymer chains. These interactions limited formation of high molecular weight copolymers during copolymerization. To exploit the strong intermolecular interactions of the 3,6-carbazole moiety, we incorporated 3,6-carbazole units into P(F-DTBT) prepared from 9′,9′dioctanyl-2,7-flourene and DTBT. Molecular weight increased gradually with increasing 2,7-fluorene monomer content but the number of conjugation breaks was a range of 67. |
