Fluorescent branched oligomers with polyphenyl and fluorenyl units

• Published in: Journal of applied spectroscopy Vol. 78; no. 3; pp. 344 - 351
• Main Authors: Nurmukhametov, R. N., Shapovalov, A. V., Sergeev, A. M., Kovalev, A. I., Kushakova, N. S., Khotina, I. A.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.07.2011; Springer
• Subjects: Analytical Chemistry; Atomic/Molecular Structure and Spectra; Chromophores; Fluorescence; Oligomers; Physics; Physics and Astronomy; UV absorption; fluorescence lifetime; fluorescence; quantum yield; branched oligophenylenes and oligofluorenylphenylenes
• ISSN: 0021-9037; 1573-8647
• DOI: 10.1007/s10812-011-9468-z

Absorption spectra and fluorescence parameters (spectra, quantum yields, and lifetimes) were obtained for a number of branched oligophenylenes (OPh) with long-wavelength chromophores such as p -quaterphenyl (OPh4-2), p -pentaphenyl (OPh5), and p -hexaphenyl (OPh6) and for oligofluorenylphenylenes (OFl) in solutions and films. It is demonstrated that the absorption spectrum of OPh4-2 is a superposition of p -quaterphenyl, p -terphenyl, and diphenyl absorption bands taken in a ∼3:2:2 ratio. The obtained OPh5 and OPh6 absorption and fluorescence spectra are shown to be determined mainly by the longest-wavelength chromophores, p -pentaphenyl and p -hexaphenyl, respectively. It is demonstrated that the obtained compounds contain traces of impurities with fluorescence at longer wavelengths than that of the base material. The branched oligomers exhibit high fluorescence quantum yields in solutions, those for OPh5 and OPh6 reaching 1. Transparent fluorescent films were produced from all of the synthesized oligomers.