Synthesis and characterization of a new alternating copolymer containing quaterphenyl and fluorenyl groups

An alternating copolymer was synthesized by Suzuki reaction from 4,4′-dibromo-p-quaterphenyl (PPP oligomer) and 9,9-dioctylfluorene-2,7-diboronic acid in good yield (84%). The copolymer is partially crystalline, readily soluble in organic solvents, presents high fluorescence quantum yield (85.6%) and high thermal stability. The copolymer absorption as well as the emission spectra are red shifted compared to those of monomers. Ultrafast time-resolved fluorescence experiments on the copolymer were carried out and confirmed the results obtained from stationary experiments. The copolymer fluorescence decay is found to be bi-exponential with fluorescence lifetimes of 297 ± 6 ps and 942 ± 5 ps.