Synthesis and characterization of new 4‐tolyldiphenylamine derivatives for hole transporting polymers

Abstract

New hole transport polymers have been synthesized by condensation polymerization of 4tolyldiphenylamine (TDPA) with various types of aldehyde. The reaction conditions have been investigated to yield polymers with high molecular weight. It is found that the molecular weight and yield of the TDPA±aldehyde polymers strongly depend on the electron donor±acceptor nature of the substituent on the aromatic ring of the aldehyde monomer. Structural characterization by 1 H NMR spectroscopy shows that the addition condensation reaction occurs exclusively at the para position of TDPA. The electrochemical and optical properties of polymers have been investigated by cyclic voltammetry and UV±vis spectroscopy. Cyclic voltammograms of all polymers show well-de®ned pairs of reduction and oxidation peaks, indicating that the polymers are electrochemically active. All polymers show low conductivities of magnitude 10 À14 S cm À1 . Differential scanning calorimetry measurements reveal that TDPA±aldehyde polymers exhibit glass transitions in the range 170±230°C. These polymers possess good solubility and the ®lms show suf®cient morphological stability.

Chemical Doping of Triphenylamine-Benzaldehyde Polymers

“…The studied polymers were prepared by condensation polymerization of 4-tolyldiphenylamine (TDPA) with benzaldehyde (BA), 4-cyanobenzaldehyde (CBA), 4-nitrobenzaldehyde (NBA) and methyl 4-formylbenzoate (MFBA) as reported earlier [10]. Two types of oxidizing agents were applied to oxidize these polymers: 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) and tetrachloro-1,4-benzoquinone 802 N. Tsukamoto et al…”

“…The other chemicals were of reagent grade and were used without further purification. The benzaldehyde-4-tolyldiphenylamine polymers were synthesized as in previous work [10].…”

“…The authors have reported previously [13] that by oxidation of triphenylamine-benzaldehyde polymers, their conductivity increased more than 100 times. It was also found that by the reaction of tolyldiphenylamine (TDPA) with other para substituted benzaldehydes it is possible to synthesize materials of the required electrochemical properties and good film-forming ability [10]. However, all prepared polymers showed low conductivities of magnitude 10 714 Scm 71 .…”

Oxidative Coupling Copolymerization of 4‐Methyltriphenylamine with Arenes

“…The compound 4-methyltriphenylamine (MTPA) was synthesized as in our previous work. [24] Dimethyltriphenylamine was prepared from aniline and 4-bromotoluene by the Tosoh method. [25] A 300-ml dried flask fitted with a magnetic stirrer and a condenser was charged with 6.53 g (70 mmol) of aniline, 24.0 g (140 mmol) of 4-bromotoluene, 16.10 g (168 mmol) of sodium tert-butoxide, 0.031 g (0.14 mmol) of palladium(II) acetate, 0.56 ml (0.56 mmol) of 1 M tri-tert-butylphosphine, and 300 ml of xylene.…”

Synthesis and Characterization of Conjugated Pyridine-(N-diphenylamino) Acrylonitrile Derivatives: Photophysical Properties

“…Typically, these dyes have a donor-acceptor structure that controls their photophysical properties (Patra, et al, 2002;Zhou, et al, 2008;Adès, et al, 2000). Aromatic amines are among the most important derivatives as materials for hole transport in nanodevices (Pai, Yanus & Stolka, 1984;Naito & Miura, 1993;Okutsu, et al, 1997;Thelakkat, et al, 1999;Yakushchenko, et al, 1999;Strzelec, et al, 2001;Jiang, et al, 2002;Loy, Koene & Thompson, 2002;Xin, et al, 2002;Chen, et al, 2003;Satoh, et al, 2003;Salbeck, 1996;Strohriegl & Grazulevicius, 2002), and have been used in a wide range of structures, either as separate layers (Salbeck, 1996;Friend, 1999) or covalently attached to light emitting layers (Loy, Koene & Thompson, 2002;Redecker, et al, 1999;Miteva, et al, 2001;Ego. et al, 2002).…”