Chain-Growth Polymerization of Unusual Anion-Radical Monomers Based on Naphthalene Diimide: A New Route to Well-Defined n-Type Conjugated Copolymers

Abstract

Strongly electron-deficient (n-type) main-chain π-conjugated polymers are commonly prepared via well-established step-growth polycondensation protocols which enable limited control over polymerization. Here we demonstrate that activated Zn and electron-deficient brominated thiophene-naphthalene diimide oligomers form anion-radical complexes instead of conventional Zn-organic derivatives. These highly unusual zinc complexes undergo Ni-catalyzed chain-growth polymerization leading to n-type conjugated polymers with controlled molecular weight, relatively narrow polydispersities, and specific end-functions.

Charge Transport Anisotropy in Highly Oriented Thin Films of the Acceptor Polymer P(NDI2OD‐T2)

“…Polymer Data and Film Preparation : Low molecular weight P(NDI2OD-T2) (P2a, P2b, P2c) was synthesized via catalyst transfer polymerization by Kiriy and coworkers, [ 36,37 ] high molecular weight P(NDI2OD-T2) (P1) was purchased from Polyera Corporation ("PolyeraActivInk N2200"). Molecular parameters and the melting points of the used samples are summarized in Table 1 and were obtained by size exclusion chromatography (SEC) in chloroform (P2a, P2b, P2c) and HT-SEC (160 °C) in trichlorobenzene (P1), both calibrated versus polystyrene, and differential scanning calorimetry (DSC), respectively.…”

“…Thereby, we studied commercially available P(NDI2OD-T2) purchased from Polyera Corporation ("PolyeraActivInk N2200") and referred to as P1, as well as three different batches of low molecular weight P(NDI2OD-T2) (denoted as P2a, P2b, P2c) synthesized via Ni-catalyzed chaingrowth polymerization. [ 36,37 ] Molecular parameters of the different batches used in this study are summarized in Table 1 . Films of around 25-100 nm thickness obtained by spin-coating from chlorobenzene were used as a starting point for the annealing experiments.…”

Recent advances in conjugated polymer energy storage

“…95 Metal-catalyzed polycondensations are also a potential method for synthesizing new n-type or specially functionalized materials. 90,96 Several recent synthetic approaches have focused upon increasing the solubility or dispersibility of conjugated polymers to enhance their processability. Side chains are essential for solubilizing conjugated polymers used in semiconducting applications, and similar concepts are applicable for electrochemical energy storage.…”

“…A major issue involves the lack of reliable synthetic methods to produce large quantities of n-type polymer. There are, however, new ways to make them using metal-catalyzed cross-couplings, 90,96 although these developments are very recent as of the time of this publication and have not been widely applied to electrode materials as of yet. There is one example, however, of an n-type polyfluorene stabilizing silicon nanoparticles in a composite anode.…”

Controlled Polymerization of Electron-deficient Naphthalene-diimide Containing Monomer by Negishi-type Catalyst-transfer Polymerization

“…The polymers containing naphthalene-diimide [13] or perylene-diimide [14], which show high electron mobility, were synthesized by Kiriy and coworkers by catalyst-transfer polymerization of the anion-radical monomer in the presence of the Pd or Ni catalyst. However, the obtained polymers possess high Đ values even though they acheive high enough MWs of the polymers.…”