Synthesis and properties of new aromatic polyamides with redox-active 2,4-dimethoxytriphenylamine moieties
Journal
Journal of Polymer Science, Part A: Polymer Chemistry
Journal Volume
48
Journal Issue
15
Pages
3392-3401
Date Issued
2010
Author(s)
Abstract
A new triphenylamine-based diamine monomer, 4,4′-diamino-2″, 4″-dimethoxytriphenylamine (2), was synthesized from readily available reagents and was reacted with various aromatic dicarboxylic acids to produce a series of aromatic polyamides (4a-h) containing the redox-active 2,4-dimethoxy-substituted triphenylamlne (dimethoxyTPA) unit. All the resulting polyamides were readily soluble in polar organic solvents and could be solution cast into tough and flexible films. These polymers exhibited good thermal stability with glass transition temperatures of 243-289°C and softening temperatures of 238-280°C, 10% weight loss temperatures in excess of 470°C in nitrogen, and char yields higher than 60% at 800°C in nitrogen. The redox behaviors of the polymers were examined using cyclic voltammetry (CV). All these polyamides showed two reversible oxidation processes in the first CV scan. The polymers also displayed low ionization potentials as a result of their dimethoxyTPA moieties. In addition, the polymers displayed excellent stability of electrochromic characteristics with coloration change from a colorless neutral state to green and blue-purple oxidized states. These anodically coloring polyamides showed high green coloration efficiency (CE = 329 cm2/C), high contrast of optical transmittance change (ΔT% = 84% at 829 nm), and long-term redox reversibility. © 2010 Wiley Periodicals, Inc.
Type
journal article