Novel isoindigo‐based conjugated polyelectrolytes: Synthesis and fluorescence quenching behavior with water‐soluble poly(p‐phenylenevinylene)s

Two novel ID-based water-soluble conjugated polymers (+)-PIDPV and (−)-PIDPV were synthesized by Heck coupling reaction. These two polyelectrolytes are both consisted of isoindigo units and phenylenevinylene units. In the UV–vis absorption spectra, both (+)-PIDPV and (−)-PIDPV exhibit broad absorption bands that almost cover the whole visible region. Photophysical investigations reveal that the fluorescence of water-soluble PPV can be efficiently quenched by oppositely charged PIDPV at a very low concentration. Cationic PPV shows an efficient quenching effect with ΚSV = 1.01 × 106 M−1 in the presence of (−)-PIDPV while the anionic PPV gives a lager quenching constant with ΚSV = 1.71 × 106 M−1 in the presence of (+)-PIDPV. Furthermore, the blend films of water-soluble PPVs and oppositely charged PIDPV also exhibit excellent quenching effect. These properties suggest that (+)-PIDPV and (−)-PIDPV are promising materials in the application of ionic photoactive layer in the organic solar cells. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2223–2237