A Novel Conjugated Polymer Consists of Benzimidazole and Benzothiadiazole: Synthesis, Photophysics Properties, and Sensing Properties for Pd²⁺

Abstract

ABSTRACT A conjugated polymer PPBIBTE based on benzimidazole and benzothiadiazole was synthesized through palladium‐catalyzed sonogashira cross‐coupling reaction. The chemical structures of the monomers and the polymer were indicated by 1 H NMR, and investigation of photophysics properties and sensing optical properties for metal ions were observed by ultraviolet–visible and photoluminescence spectroscopy. PPBIBTE showed remarkable selectivity for Pd 2+ by “turn‐off” fluorescence sensing progress. In addition, the Stern–Volmer and Benesi‐Hildebrand plots were used to reveal the interaction between the polymer and Pd 2+ , while job's method was applied to calculate the determination of stoichiometry. The results demonstrate that PPBIBTE can utilize static quenching for Pd 2+ by forming a 1:1 complex. And it is a potential sensing material as fluorescence chemosensor for Pd 2+ with high selectivity and sensitivity. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58 , 831‐842