Pathways to Functional Polymers: Chemically versus Electrochemically Synthesized Polypropylenedioxythiophene Derivatives

The ability to control the properties of the resulting polymer, namely, molecular weight, polydispersity, functionalization, architecture, chemical defects, doping, purity, etc., has made polymerization methodology significantly impact material science and device fabrication. Therefore, selecting a suitable polymerization method for synthesizing polymers is crucial for optimizing performance in different applications. In this study, we report and compare two polymerization techniques: chemical and electrochemical polymerization. Direct heteroarylation polymerization is employed as the chemical polymerization method, while electrochemical polymerization has been done using a potentiodynamic approach in a TBAClO 4 /MeCN electrolyte-solvent system on a working electrode. Both polymerization methods were used to synthesize poly(3,4-propylenedioxythiophene) ( PProDOT ) and its alkyl derivative, PProDOT-Bu 2, and to study their properties. The polymer synthesized via chemical polymerization is denoted as c- PProDOT, while those polymers synthesized via electrochemical polymerization are denoted as e- PProDOT . All of the polymers were thoroughly characterized. Optical and electrical characterizations were analyzed using UV–visible spectroscopy and cyclic voltammetry. Surface morphology, spectroelectrochemical behavior, and electrochromic properties were also investigated. The spectroelectrochemically measured band gaps are in the range of 1.74–1.84 eV, and correlations were established between the polymerization method and various properties such as electrochemical, optical, peak width, position of maximum absorption peak, and absorption intensity. Finally, density functional theory calculations of these polymers were performed and compared with the experimental results. This study demonstrates the ability to control the chemical and physical properties of polymers through the selection of appropriate polymerization techniques and structural design of moieties. These findings offer valuable insights into choosing suitable polymerization techniques for developing efficient materials for electronic applications.