Electropolymerized Three-Dimensional Randomly Branched EDOT-Containing Copolymers

Abstract

The potential of 2,2';3,2″-terthiophene (3T) as branching units in 3D copolymers is presented with EDOT as an example comonomer. Branched EDOT/3T polythiophenes were prepared by electropolymerization, and their electrochemical and optical properties are discussed. Two different approaches were employed: (i) the direct electropolymerization of a novel branched thiophene monomer (3TE3) consisting of a 3T core that contains three outer EDOT end groups and (ii) the electrochemical copolymerization of a EDOT/3T mixture in different ratios from [1:1] to [1:10]. Cyclic voltammetric and vis spectrometric experiments show that the EDOT content within the polymer has a strong influence on the electronic properties of the material: with increasing EDOT content, the HOMO-LUMO gap is decreased. To prove copolymer formation of EDOT and 3T, chemically synthesized reference copolymers of EDOT and 3T were prepared by oxidative coupling using FeCl3, and their optical and electronic properties were compared to those of the electrodeposited films. In addition, the copolymer formation is indicated by the comparison of the electrochemical and spectroscopic results with those of the homopolymers P3T and PEDOT.

Exploring the electrochromic properties of poly(thieno[3,2-b]thiophene)s decorated with electron-deficient side groups

“…Dioxane, N,N-dimethylformamide (DMF) and toluene were dried over 4 Å molecular sieves. 3,6-Dibromothieno [3,2-b]thiophene (1) 36 and 2-tributylstannyl-3,4-ethylenedioxythiophene (5) 37 were synthesized according to the literature procedures.…”

“…S19, ESI †). This might indicate that initially the deprotonated/dedoped polymer film undergoes ( partial) protonation during anodic cycling, perhaps, by protons formed by an oxidation of traces of water 48 to be present in the film (or in the solvent). Thiophene-pyridine copolymers with a pyridine ring in the main chain have been previously studied, [49][50][51] and it was shown that the pyridine ring is sufficiently basic to be protonated.…”

Branched Terthiophenes in Organic Electronics: From Small Molecules to Polymers

“…The electropolymerization of structures 32 – 34 will be discussed below. An EDOT‐endcapped 3T‐terthiophene ( 35 ) was synthesized in our group and also applied as monomer in electropolymerizations …”

“…Recently our group published on the synthesis of a related monomer ( 35 , Scheme ) consisting of a 3T core and three attached EDOT end groups . The electropolymerization thereof yields a polymer which has a HOMO‐level lying in between the HOMO‐levels of the polymers P(3T) and PEDOT.…”

“…The Inset shows the absorption spectra of the two polymers on ITO. Reproduced with permission . Copyright 2013, American Chemical Society.…”