Synthesis, photophysical properties, and self-assembly behavior of amphiphilic polyfluorene: unique dual fluorescence and its application as a fluorescent probe for the mercury ion.
Two new fluorene-based copolymers PFOH and PHOH were synthesized through Suzuki-coupling reaction, with p-N,N-bis-(2-hydroxyethyl)aminophenyl and bis(6'-(diethanolamino)hexyl) as side chains, respectively. They were characterized by (1)H NMR, IR, and gel-permeation chromatography (GPC). PFOH shows blue-green emission in THF, and the long emission band exhibits significant bathochromic shift with the increase in solvent polarity, whereas PHOH exhibits a bright blue emission regardless of the solvent polarity. The fluorescence emission behavior of PFOH is analogous to its corresponding terfluorene TFOH, indicating the existence of the intramolecular through-space charge transfer upon being copolymerized into a polymer. Taking advantage of the unique dual emissions, PFOH displays ratiometric "turn-on" responses for Hg(2+). In addition, the two new polymers show an amphiphilic feature and can form self-assembled nanostructures in a THF-H(2)O system, which has influence on their photophysical properties.
Department of Chemistry, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan 430072, P. R. China.
Linna
L
Zhu
Jingui
J
Qin
Chuluo
C
Yang