Polymers 2010, 2(3), 159-173; doi:10.3390/polym2030159
Article

Synthesis and Properties of 1,8-Carbazole-Based Conjugated Copolymers

1,2,* email, 1 and 1
Received: 28 June 2010; in revised form: 19 July 2010 / Accepted: 29 July 2010 / Published: 30 July 2010
(This article belongs to the Special Issue Conductive Polymers)
Download PDF [1289 KB, uploaded 30 July 2010]
Abstract: A new series of conjugated carbazole polymers based on the 1,8-carbazolylene unit was synthesized by the Pd-catalyzed polycondensation between the 1,8-diiodocarbazole derivative and various bifunctional counter comonomers. An alkyne spacer was found to be a key to increasing the molecular weight of the resulting polymers. All the obtained polymers showed good solubilities in the common organic solvents, and they were fully characterized by Gel permeation chromatography (GPC), and 1H NMR and infrared (IR) spectroscopies. The UV-vis absorption and fluorescence spectra revealed the relationship between the chemical structure and effective conjugation length. The efficiency order of the carbazole connectivity was 2,7-carbazolylene > 1,8-carbazolylene > 3,6-carbazolylene. The electrochemical properties of these polymers suggested the relatively facile oxidation at ca. +0.5–0.7 V vs. Fc/Fc+ or a high potential as p-type semiconductors. The combination of the electrochemical oxidation potentials and the optical band gaps allowed us to estimate the HOMO and LUMO levels of the polymers. It was shown that the energy levels of the 1,8-carbazole-based conjugated polymers can be tunable by selecting the appropriate comonomer structures.
Keywords: carbazole; conjugated polymer; electrochemistry; UV-vis absorption
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Export to BibTeX |
EndNote


MDPI and ACS Style

Michinobu, T.; Osako, H.; Shigehara, K. Synthesis and Properties of 1,8-Carbazole-Based Conjugated Copolymers. Polymers 2010, 2, 159-173.

AMA Style

Michinobu T, Osako H, Shigehara K. Synthesis and Properties of 1,8-Carbazole-Based Conjugated Copolymers. Polymers. 2010; 2(3):159-173.

Chicago/Turabian Style

Michinobu, Tsuyoshi; Osako, Haruka; Shigehara, Kiyotaka. 2010. "Synthesis and Properties of 1,8-Carbazole-Based Conjugated Copolymers." Polymers 2, no. 3: 159-173.


Polymers EISSN 2073-4360 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert