Synthesis of poly(9,9-dioctylfluorene) in a rotating packed bed with enhanced performance for polymer light-emitting diodes†
Abstract
One of the most suitable methods for synthesizing conjugated polymers is the Suzuki cross-coupling reaction because of its high tolerance and stability. Herein, we report an improved strategy to synthesize conjugated polymers via Suzuki cross-coupling polymerization in a rotating packed bed (RPB) reactor. The synthesis of poly(9,9-dioctylfluorene) (PFO) was systematically investigated. The enhancement of mixing and mass transfer from the RPB ensured the uniformity of the contact probability of active functional groups and the consistency of the growth rate of molecular chains. Therefore, under the optimized experimental parameter of 2.0 mmol monomer equivalents, the polydispersity index (PDI) of the PFO synthesized in the RPB was maintained at about 2.0, which was much lower than that of the traditional synthesis method in stirred reactors. Further, the performance of polymer light-emitting diodes prepared using PFO with a low PDI was more stable.