Synthesis of Conjugated Main-Chain Ferrocene-Containing Polymers through Melt-State Polymerization

Two kinds of conjugated main-chain ferrocene (Fc)-containing polymers, PFcT8 and PFcTP8, were successfully prepared through the facile melt-state polymerization (MSP) of corresponding monomers which combine the Fc motif with thiophene or thiophene-methane groups. The simple, low-cost MSP was chosen as the method, while thiophene or thiophene-methane groups served as reactive sites for its feature of easy polymerization by a simple heating process. The prepared metallopolymers were characterized by 1H NMR, FTIR, and photochemical and electrochemical analysis, metal content, and thermal stability. The results show that metallopolymers with a regular backbone and nearly quantitative metal content were obtained. In addition, the metallopolymer PFcTP8 has the smallest optical band gap (absorption edge at 1100 nm) and high thermal stability among reported Fc-containing polymers, which indicates the thiophene-methane-based Fc-containing structure is a good candidate to construct functional polymers through MSP. The low band gap and high thermal stability of prepared conjugated metallopolymers show their potential application in conducting materials with high working temperature.