Thermally driven self‐healing PEDOT conductive films relying on reversible and multiple Diels–Alder interaction

Abstract

Thermally healing capability of cracks and defects is important and urgent for the safe operation and life extending of electric materials and devices. Here, by the combination of thermally driven reversible Diels-Alder (DA) interaction and in-situ chemical oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT), a series of intrinsically conductive poly(3,4-ethylenedioxythiophene) (PEDOT)/DA composites possess intrinsically self-healing property under lowtemperature (reverse DA reaction at 100 C; DA crosslinking at 60 C) stimulus were achieved. The crosslinking DA bonding reactions are multiple from the co-existence of pre-synthesized macromolecular polyurethane attached DA units (PU-DA) and 2,4-hexadiyne-1,6-diol (DADOL) in the films. PU-DA involved in the polymerization process of EDOT to endow PEDOT with outstanding solution-processability, uniform film making, and structural self-healing capability, while DADOL was added to enhance the cross bonding between polymer chains. This work will accelerate the research and application development of intrinsically self-healing conducting polymers for commercial capacitors, antistatic coatings, implantable, printable electronics, and so on.

Self-healable PEDOT-based all-organic films with excellent electrochromic performances

“…Unlike the direct use of the mixture solution after the synthesis reaction of PU-DA in our previous work, 18 where although the “one-pot” method was simple it may bring impurities with PU-DA into its subsequent use, in this research, pure PU-DA was used as an emulsifier and template for the following in situ oxidative polymerization of EDOTs.…”

“…PU-DA was synthesized according to our previously reported procedure with modifications 18 (see Scheme S1 (ESI†) for the synthetic route). The detailed experimental procedure is illustrated as follows.…”

“…In addition, the influence of extra conductive promoters and other additives on self-healing should be considered. 9,16,18 Moreover, the intrinsic shortcomings of PEDOT:PSS, such as coming from a strongly acidic aqueous solution with harsh storage conditions and shorter storage time, strong moisture absorption, etc. should be severely considered.…”

“…In our recent report, 18 instead of using aqueous processable PEDOT:PSS, we have developed a feasible strategy using an organic processing system to achieve a series of intrinsically conductive composites relying on in situ chemically polymerized PEDOT and pre-synthesized macromolecular polyurethane attached DA units (PU-DA). Under a low-temperature stimulus, the composite films possess intrinsic self-healing and conductive properties by the combination of PEDOT and thermally driven reversible DA/r-DA interaction.…”

“…As a follow-up work to before, 18 in this study, we developed an organic processing strategy to fabricate composite polymer films which simultaneously integrated electrochromic PEDOTs and thermally self-healable PU-DA (without supplementary DADOL) from in situ oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) or/and its hydroxymethyl derivative (EDTM) (Fig. 1).…”