Syntheses and characterization of benzimidazole containing polymers: a comparative study on donor unit effect and influence of H-bonding

Nurioğlu, Ayda Gökçek
The first part of this work reports a comparative study on electrochromic properties of two Donor-Acceptor-Donor (DAD) type polymers, namely poly(2-heptyl-4,7-di(thiophen-2-yl)-1H-benzo[d]imidazole) (BImTh) and poly(4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2-heptyl-1H-benzo[d]imidazole) (BImEd). DAD type polymers are designed to bear the same acceptor unit, benzimidazole and two different donor units, thiophene and 3,4-ethylenedioxy thiophene (EDOT) to make a comparison based on the donor unit effect. The resulting polymers are both multichromic and have low band gap values (1.93 eV for PBImTh and 1.74 eV for PBImEd). In the second part, 4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2-phenyl-1H-benzo[d]imidazole (BImBEd) is synthesized. In order to figure out the presence of an intramolecular hydrogen bonding between the amine bond of the imidazole ring and the oxygen of the EDOT molecule, different amounts of trifluoroacetic acid (TFA) and concentrated sodium hydroxide (NaOH) solutions were added during electrochemical polymerization. These treatments caused protonation of the imine and deprotonation of the amine bonds respectively. In order to prove the changes in the optical properties of the polymers due to different number of protonated and deprotonated imine and amine bonds, 1,4-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)benzene (BEDOT-B) was also synthesized and treated with the same procedures. Results showed that it is possible to control the main chain conformation of even an insoluble polymer via acid and base treatments during in situ polymerization.


Multichromic benzimidazole-containing polymers: Comparison of donor and acceptor unit effects
Nurioglu, Ayda Goycek; Akpinar, Hava; Sendur, Merve; Toppare, Levent Kamil (2012-09-01)
This study reports a comparative study on electrochromic properties of two donoracceptordonor (DAD)-type polymers namely poly(2-heptyl-4,7-di(thiophen-2-yl)-1H-benzo [d]imidazole) (BImTh) and poly(4,7-bis(2,3-dihydrothieno[3,4-b] [1,4]dioxin-5-yl)-2-heptyl-1H-benzo[d]imidazole) (BImEd). DAD-type monomers were polymerized electrochemically on indium tin oxide-coated glass slides to determine the optical properties of the polymers. Electrochemical rho-doping experiments were performed to determine the band ga...
Synthesis of electroactive benzimidazole derivatives and their electrochromic properties
Özelçağlayan, Ali Can; Toppare, Levent Kamil; Çırpan, Ali; Department of Chemistry (2012)
In order to study their electrochemical and optical properties, two donor-acceptordonor (D-A-D) type monomers; 4'-(tert-butyl)-4,7-bis(4-hexylthiophen-2- yl)spiro[benzo[d]imidazole-2,1'-cyclohexane] (BIHT) and 4'-(tert-butyl)-4,7-bis(2,3- dihydrothieno[3,4-b][1,4]dioxin-5-yl)spiro[benzo[d]imidazole-2,1'-cyclohexane] (BIED), were electrochemically polymerized. These properties were investigated by cyclic voltammetry and UV–Vis-NIR Spectroscopy techniques. Effects of different donor groups; 3-hexylthiophene a...
Synthesis and electrochemical studies of fluorene and benzimidazole containing conjugated polymers
Namal, İmge; Toppare, Levent Kamil; Arslan Udum, Yasemin; Department of Chemistry (2013)
The synthesis and characterization of two donor acceptor type conjugated polymers were investigated. The electrochemical properties were examined using cyclic voltammetry, spectroelectrochemistry and kinetic studies. The increase in the alkyl chain length attached to the fluorene unit was investigated by the corresponding electrochemical characteristics. The synthesis was carried out via Stille coupling of 4,7- dibromo-4'-(tert-butyl)spiro[benzo[d]imidazole-2,1' cyclohexane] and 2,5- bis(tributylstannyl)thi...
Synthesis and characterization of optical, electrochemical and photovoltaic properties of selenophene bearing benzodithiophene based alternating polymers
Atli, Gulten Ozkul; Alemdar, Eda; Taşkaya Aslan, Sultan; Udum, Yasemin Arslan; Toppare, Levent Kamil; Çırpan, Ali (Elsevier BV, 2020-04-01)
In this study two donor-acceptor type alternating polymers containing electron-deficient benzotriazole moiety and electron-rich selenophene bearing benzodithiophene moiety; P1 and P2, were designed and synthesized via Stille polymerization. Moreover, the effects of thiophene and selenophene as pi-bridges on optical, electrochemical and optoelectronic features of polymers were examined. The optical band gap values of P1 and P2 were found as 1.47 eV and 1.72 eV, respectively. Cyclic voltammetry studies were p...
Synthesis and characterization of electrochemically polymerized metal-free, nickel and zinc containing phthalocyanine derivatives
Yavuz, Arzu; Aras, Leyla; Department of Polymer Science and Technology (2009)
In the first part of this study, 4-(2,5-di-2-thiophen-2-yl-pyrrol-1-yl)-phthalonitrile (SNS-PN) was synthesized by utilizing 1,4-di(2-thienyl)-1,4- butadione (SOOS) and 4-aminophthalonitrile via Knorr-Paal Reaction. Nuclear magnetic resonance (1H NMR and 13C NMR) and fourier transform infrared (FTIR) spectroscopies were utilized for the characterization of this compound. SNS-PN monomer was then electrochemically polymerized in acetonitrile/0.2 M LiClO4 solvent/electrolyte couple. Characterizations of the re...
Citation Formats
A. G. Nurioğlu, “Syntheses and characterization of benzimidazole containing polymers: a comparative study on donor unit effect and influence of H-bonding,” M.S. - Master of Science, Middle East Technical University, 2013.