Impact of oxidation-induced ordering on the electrical and mechanical properties of a polythiophene co-processed with bistriflimidic acid

Abstract

The interplay between the nanostructure of a doped polythiophene with oligoether side chains and its electrical as well as mechanical properties is investigated.

Impact of doping on the mechanical properties of conjugated polymers

“…ε break decreased from about 160% to less than 30%. 39,118 Interestingly, doping with F 2 TCNQ retained the ductility to a greater extent for a similar oxidation level of about 6.4%, as evidenced by a similar E = 31 MPa but higher ε break ≈ 60% (Fig. 13).…”

“…15 ). 118 Shorter triethylene glycol side chains give rise to a stiffer polymer, p(g 3 2T-T), with E = 76 MPa, which upon doping with 20 mol% F 4 TCNQ increased to 826 MPa. 84 …”

Impact of Oligoether Side-Chain Length on the Thermoelectric Properties of a Polar Polythiophene

“…Interestingly, p(g 6 2T-T) exhibits the weakest absorption intensity, which can be rationalized with its larger side-chain fraction. Additional absorption peaks, located in the nearinfrared (NIR) region at 0.5 eV and around 1.3 eV in case of p(g 3 2T-T) (Figure 3), are observed, which arise due to adventitious oxidation of the backbone by atmospheric oxygen 34 resulting in a weakly doped polymer. 35 The absorption spectra of the three polymers coprocessed with 20 mol % of F 4 TCNQ do not show any significant absorption arising from the neat material (Figures 3 and S3), indicating strong oxidation of the backbones.…”

“…When the polymer is coprocessed with 20 mol % F 4 TCNQ, the material becomes significantly stiffer, with a Young’s modulus E = 826 ± 141 MPa, but retains a similar ε b = 5 ± 2%. This result aligns with recent studies that highlight molecular doping as an effective tool for tuning not only the electrical but also the mechanical properties of conjugated polymers. , …”

Influence of Different Polymorphs on the Electrical and Mechanical Properties of F4TCNQ-Doped Regioregular P3BT Films

“…In the early 1990s, Smith’s group first reported that the elastic modulus E f of P3ATs (P3HT, poly­(3-octylthiophene) (P3OT), and poly­(3-dodecylthiophene) (P3DDT)) increased after doping with ferric chloride (FeCl 3 ) or iodine (I 2 ). , The impact of doping on the mechanical properties of CPs has not yet received much attention. In recent years, Müller’s group performed much work in this direction. − They investigated the variation in the E f and COS of CPs (including polythiophene with tetraethylene glycol side chains (p­(g 4 2T-T), P3HT, and P3DDT) before and after doping. They considered that the E f of CPs tends to decrease upon doping if the neat polymer is stiff, i.e., E f ≫ 100 MPa, likely due to a plasticization-type effect of the dopant in CPs; instead, doping softer polymers with E f < 100 MPa has been found to increase the modulus due to an increase in crystalline order after doping.…”