Synthesis and properties of well-defined carbazole-containing fluorescent star polymers of different arms

A series of fluorescent carbazole-containing star polymers with different arms were successfully synthesized using 9-(4-vinylbenzyl)-9H-carbazole (VBCz) as monomer and multifunctional bromide as initiators via atom transfer radical polymerization (ATRP). The effect of the poly(9-(4-vinylbenzyl)-9H-carbazole) (PVBCz) star polymer architecture on their optical and electrochemical properties was investigated. All of the PVBCz star polymers absorbed light in the range of 280-360 nm both in solution and as polymer films. Meanwhile, the star polymers exhibited maximum fluorescent emission at 350 nm in solution, while at 406 nm as films. Moreover, the star polymers with different arm numbers showed different photoluminescence quantum efficiency and highest and lowest occupied molecular orbital (HOMO, LOMO, respectively) energy levels. It is proved that the PVBCz star polymers exhibited different photoelectronic properties by varying the molecular architectures.