Abstract Two benzimidazole-based conjugated polyelectrolytes (+)-PPBIPV and (-)-PPBIPV which have opposite charges on their side chains were synthesized via Heck coupling reaction and characterized by 1H-NMR, UV-vis and PL spectroscopy. These two polyelectrolytes are both consisted of benzimidazole derivatives and phenylenevinylene units. The absorption and emission spectra reveal that the polymers both have solvent-dependency and concentration-dependency, and they exhibit aggregation effect in aqueous solution. In the respect of ion detection, the aqueous solution of (+)-PPBIPV has excellent selectivity and sensitivity for Fe3+. Moreover, Pd2+ can almost completely quench the fluorescence of (+)-PPBIPV in methanol solution, and its quenching constant KSV is 5.93×104 M-1. For (-)-PPBIPV, Sn2+ can double the fluorescence intensity of its aqueous solution, while (-)-PPBIPV has good identification for Fe3+ in methanol with a KSV = 3.44×105 M-1. Hence, two polyelectrolytes have considerable potential to become effective fluorescent sensing materials for some specific metal ions. All of the stoichiometric relationships between metal ions and conjugated polyelectrolytes were calculated using Benesi-Hildebrand equation.

中文翻译：

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新型苯并咪唑基共轭聚电解质：金属离子的合成、溶液光物理和荧光传感

摘要 通过Heck偶联反应合成了两种侧链带相反电荷的苯并咪唑基共轭聚电解质(+)-PPBIPV和(-)-PPBIPV，并用1H-NMR、UV-vis和PL光谱对其进行了表征。这两种聚电解质均由苯并咪唑衍生物和亚苯基亚乙烯基单元组成。吸收光谱和发射光谱表明聚合物均具有溶剂依赖性和浓度依赖性，在水溶液中表现出聚集效应。在离子检测方面，(+)-PPBIPV的水溶液对Fe3+具有优良的选择性和灵敏度。此外，Pd2+在甲醇溶液中几乎可以完全淬灭(+)-PPBIPV的荧光，其淬灭常数KSV为5.93×104 M-1。对于 (-)-PPBIPV，Sn2+ 可以使其水溶液的荧光强度增加一倍，而 (-)-PPBIPV 对甲醇中的 Fe3+ 具有良好的识别性，KSV = 3.44×105 M-1。因此，两种聚电解质具有成为某些特定金属离子有效荧光传感材料的巨大潜力。使用 Benesi-Hildebrand 方程计算金属离子和共轭聚电解质之间的所有化学计量关系。