A series of water-soluble copolymers, named N-PFPx (x = 10, 25, and 50), and their model compound 6,6',6'',6'''-(2,2'-(2-hydroxy-5-methoxy-1,4-phenylene)bis(9H-fluorene-9,9,2-triyl))tetrakis(N,N,N-trimethylhexan-1-aminium) bromide (FMOPF) were synthesized by Suzuki coupling reaction of fluorene derivatives and p-methoxyphenol. For the polymers with relatively low contents of methoxyphenol (N-PFP10 and N-PFP25), the absorption and fluorescence spectra could be mainly ascribed to the polyfluorene, whereas for the polymer N-PFP50 and the model compound FMOPF, the absorption and fluorescence spectra could be assigned to the fluorene-alt-methoxyphenol. All the conjugated polymers (CPs), regardless of the content of methoxyphenol moieties, exhibit good sensitivity to hypochlorite/hypochlorous acid (HClO) because of the superquenching effect of CPs. On the contrary, the absorption changes of the polymers N-PFPx on the addition of hypochlorite/HClO depend on the content of methoxyphenol moieties. As the content of methoxyphenol moieties increase, the changes of absorption spectra become more intense. Considering the sensitivity and selectivity, the polymer N-PFP10 and N-PFP25 have been demonstrated to be good polymeric fluorescent probes to hypochlorite under the aqueous condition. (c) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012