Synthesis and Electrochemical Properties of Well-Defined Norbornene-B-ferrocene-dioxaborolane Hybrid Polymeric Material

This study presents an effective synthesis and characterization of an original norbornene-B-ferrocene-dioxaborolane hybrid polymeric material via ring opening metathesis polymerization (ROMP). The resulting material was investigated for its electrochemical, thermogravimetric, and SEM properties. A catalytic method was used to synthesize unfamiliar materials of poly(5-norbornene-2-<i>exo</i>,3-<i>exo</i>-dimethyl-[(ferrocene)-dioxaboronane])s (<b>2</b>) in a selective and effective manner. During the initial stage of the study, monomer <b>1</b> was designed with a well-defined <i>exo</i>-structure to be optimally suited for catalytically controlled ROMP using the active Grubbs ruthenium(II) initiator. X-ray measurements confirmed a structure. The material <b>2</b> has a regular, linear structure of the main matrix-carrier ferrocenyl pendant groups (type: ...-=-A-=-A-=-A-=-...). It exhibits excellent reduction-oxidation properties and a good electrochemical stability. The device exhibited a high transmittance of over 95% between 550 and 1000 nm in the bleached state. Upon application of a voltage of 1.5 V, a decrease in transmittance was observed across the entire optical window tested. The highest optical contrast of 28% was observed at 420 nm. The study investigated the electrochromic stability by alternating the potential between +1.5 V and -1.0 V at 30 s intervals and monitoring the transmittance difference at 420 nm over time.