Liquid/Liquid Interfacial Suzuki Polymerization Prepared Novel Triphenylamine-Based Conjugated Polymer Films with Excellent Electrochromic Properties

Abstract

Preparing conjugated polymer films via interfacial Suzuki polymerization is a promising method for obtaining desirable electrochromic materials with desired structures. Here, a series of aryl boronic esters and triphenylamine-based aryl bromides were applied as precursors, and several polymer films were finally obtained via the liquid/liquid interfacial Suzuki polymerization reaction under mild conditions. FT-IR, UV, and Raman as well as electrochemistry, SEM, and EDS results all provide strong evidence for the formation of the desired polymer structures. Among them, the TPA-Wu (containing triphenylamine and alkyl-fluorene) film exhibits the best film-forming quality. Besides, these polymer films were applied in electrochromic applications. The results show that electrochromic properties can be affected by the quality of film formation. It is worth mentioning that the TPA-Wu film could achieve excellent electrochromic properties with reversible multicolor changes from transparent yellow to orange-red to blue-green under varying potentials. Compared to other triphenylamine-based electrochromic materials, the TPA-Wu film possessed the most desirable coloring efficiency, higher optical contrast, and shorter switching time. This work provides an existing general approach of liquid/liquid interfacial Suzuki polymerization for constructing conjugated polymer films toward electrochromic applications.

Reversible color modulation of luminescent conjugated polymers based on a chemical redox mechanism and applications in rewritable paper and multiple information encryption

“…As one of the most promising research directions for rewritable paper and information encryption, the reversible control of material color and fluorescence has made great progress in recent years. Many methods including photochromism, [11][12][13][14][15] mechanochromism, [16][17][18] electrochromism [19][20][21][22][23] and so on have been reported to achieve reversible color modulation of materials. For example, the reversible color modulation property of hydrochromic materials was utilized in the fabrication of inkless rewritable paper, which could achieve reversible color switching via heterolytic scission of a C-O bond promoted by water.…”

From gas separation to ion transport in the cavity of hyperbranched polyamides based on triptycene aimed for electrochromic and memory devices

“…The EC polymers are generally of two kinds: the common one is conducting polymers (CPs) such as polyaniline, polythiophene and polypyrrole; the other is high performance polymers (HPPs) such as polyamide (PA), polyimide (PI), polyurethane (PU), etc . 2–4 Many CPs have limited application in screens or smart windows because their neutral state has intrinsic colors due to a narrow energy band. However, as for HPPs, they are transparent or only a little yellow in color in the neutral state which are in tune with the demand for smart windows.…”

Highly electrochemically and thermally stable donor–π–acceptor triphenylamine-based hole-transporting homopolymersviaoxidative polymerization

“…34,39,42,44 However, the general drawbacks of D-A copolymers are that most of them are synthesized via cross-coupling reactions and using toxic organotin compounds as well as expensive catalysts based on noble metals. [44][45][46][47] These problems can be overcome using D-A homopolymers 27,48,49 instead of copolymers since the former can be prepared via rather simple oxidative polymerization. The oxidative polymerization of triphenylamines 27,[50][51][52] smoothly proceeds at room temperature using rather cheap oxidants such as iron(III) chloride and without the need to prepare difunctional monomers with either halogen, organoboron or organotin groups.…”

“…The oxidative polymerization of triphenylamines 27,[50][51][52] smoothly proceeds at room temperature using rather cheap oxidants such as iron(III) chloride and without the need to prepare difunctional monomers with either halogen, organoboron or organotin groups. Altogether, this approach reduces the number of synthetic steps and makes the process more environmentally friendly as compared to the methods of TPA-based polymer synthesis by crosscoupling reactions such as Suzuki, 46,47 Stille 44 or Yamamoto. 53 However, D-A triphenylamine homopolymers are poorly studied and their number described in the literature includes just several examples.…”