Polymers, chains of molecules of high molecular weight, have played a key role in the development of technology and society. As a result of advances in research, synthesis and application, polymers are used widely, from medicine to electrical engineering. Their diverse properties, such as low density, flexibility and thermal insulation, allow adaptation to different needs. In modern times, the focus is shifting towards conductive polymers that combine electrical conductivity with other properties. Further research is essential to optimize conductive polymers and expand their applications, such as wearable electronics and solar cells, and to create innovations in areas such as electronic skin. One example of an electrically conductive polymer whose application is constantly expanding is poly(3,4-ethylenedioxythiophene) (PEDOT). By tailoring the properties of PEDOT through controlled polymerization methods such as chemical oxidation polymerization or electrochemical polymerization, it is possible to direct its use to a specific application. Within this study, a PEDOT-HMBr macroinitiator was synthesized by chemical oxidative polymerization. The synthesis consisted of two stages. In the first stage, the (2,3-dihydrothieno[3,4-b][1,4]dioxin-2-yl)methyl 2-bromo-2-methylpropanoate (HMBr) monomer was obtained, and in the second, the PEDOT-HMBr macroinitiator polymer. The obtained sample was characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA) and electrical conductivity measurement. Characterization of the material through FTIR, NMR and TGA analyses confirmed the presence of characteristic groups, the HMBr to EDOT unit ratio and the thermal stability of the polymer. The electrical conductivity of the doped sample was significantly increased compared to the pure polymer. Despite achieved results, further research is required to enhance the macroinitiator's electrical conductivity for broader application possibilities.