Synthesis and properties of two novel regioregular conjugated polythiophenes with side-chain containing different substituted end groups

摘要

Two soluble conjugated polythiophenes, poly[3-(N-butyl-4-piperidinemethylene)-thiophene] (P3BLMT), and poly[3-(N-butyryl-4-piperidinemethylene)-thiophene] (P3BRMT) have been synthesized successfully in chloroform using FeCl_(3) as an oxidizing agent. In P3BLMT and P3BRMT, substituted piperidine rings are connected with the polythiophene backbone through carbon–carbon double bond. While in the two polythiophenes, the significant difference is the substituent linked to the N-atom of the piperidine effectively. Structures of the monomers and the corresponding soluble polymers were elucidated by ~(1)H NMR, ~(13)C NMR, and IR. Average molecular weights have been determined by gel permeation chromatography. Photoluminescence spectra and ultraviolet–visible spectra of the two polythiophenes in both solution and solid states were also investigated, and all peaks were bathochromically shifted when they were measured in the solid state. The results of optical and electrochemical measurements indicate that the carbonyl group on the side-chain has obvious influence on the electrochemical properties of the conjugated polythiophenes. In addition, the polymers were also characterized by cyclic voltammetry and scanning electron microscopy.