Umut Bulut - Academia.edu (original) (raw)
Papers by Umut Bulut
![Research paper thumbnail of Synthesis, characterization and electrochromic properties of conducting copolymers of 3-[(3-thienylcarbonyl)oxy]-2,2-bis{[(3-thienylcarbonyl)oxy]}propyl 3-thiophene carboxylate with thiophene and pyrrole](https://attachments.academia-assets.com/81369422/thumbnails/1.jpg)
](Reactive & Functional Polymers, 2004
3-[(3-Thienylcarbonyl)oxy]-2,2-bis{[(3-thienylcarbonyl)oxy]}propyl 3-thiophene carboxylate (TOTPT... more 3-[(3-Thienylcarbonyl)oxy]-2,2-bis{[(3-thienylcarbonyl)oxy]}propyl 3-thiophene carboxylate (TOTPT) was synthesized by the reaction of 3-thionylcarbonyl chloride with pentaerythritol, it was electrochemically polymerized with either thiophene or pyrrole by using tetrabutylammonium tetrafluoroborate (TBAFB) as the supporting electrolyte in acetonitrile (AN). Characterization of the resulting copolymers was carried out by FTIR spectroscopy, cyclic voltammetry, thermal gravimetry analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Electrical conductivities of the copolymers were measured by the four-probe technique. The electrochemically synthesized copolymer was found to be capable of switching between an orange reduced state and a greenish-blue color oxidized state, and has an electronic band gap of 1.95 eV. The copolymer exhibited a long-term switching stability up to 400 double switches.
Journal of Applied Polymer Science
A novel benzenediamine-benzodithiophene polymer is synthesized for use in biosensor fabrication f... more A novel benzenediamine-benzodithiophene polymer is synthesized for use in biosensor fabrication for the detection of testosterone. The sensory platform is constructed via drop coating on a screen-printed carbon electrode, using poly(benzenediamine-Bis[(2-ethylhexyl)oxy]benzodithiophene) (pBDBT) as the polymer layer. Testosterone antibodies are immobilized on the polymercoated electrode surface via glutaraldehyde, which binds to the surface through the amino functional groups on the polymer backbone. The changes in the surface features due to testosterone binding are investigated via electrochemical techniques such as differential pulse voltammetry, cyclic voltammetry, and electrochemical impedance spectrometry as well as contact angle measurements. Surface morphology of the modified electrodes is characterized by atomic force microscopy. The linear range and limit of detection of the sensor are calculated. Impact of possible interfering compounds is investigated. Furthermore, the sensory platform is utilized for testosterone analysis in synthetic biological fluids.
Designed Monomers & Polymers
ABSTRACT
Polymer, 2013
ABSTRACT This article describes the use of functionalized quinoxaline derivatives as photosensiti... more ABSTRACT This article describes the use of functionalized quinoxaline derivatives as photosensitizers for diaryliodonium salt photoinitiators. Highly conjugated compounds with good absorption bands in long wavelength UV and visible region are presented. These versatile intermediates facilitate photoinitiated cationic polymerization of commercially important monomers such as cyclic ethers and vinyl epoxides. Polymerizations were carried out using long wavelength UV light in the presence of diphenyliodonium hexafluorophosphate (Ph2I+PF6-). The polymerizations were monitored by optical pyrometry (OP). In addition, we also demonstrate that it was also possible to initiate photopolymerizations under solar irradiation in the presence of these photosensitizers. (c) 2013 Elsevier Ltd. All rights reserved.
Macromolecules, 2005
ABSTRACT
Macromolecular Symposia, 2006
ABSTRACT
Journal of Polymer Science Part A: Polymer Chemistry, 2005
Curcumin, a naturally occurring, intensely yellow dye extracted from the spice turmeric, is an ef... more Curcumin, a naturally occurring, intensely yellow dye extracted from the spice turmeric, is an efficient photosensitizer for diaryliodonium salt photoinitiators at wavelengths ranging from 340 to 535 nm. With curcumin as a photosensitizer, it is possible to carry out the cationic photopolymerization of a wide variety of epoxide, oxetane, and vinyl monomers with long-wavelength UV and visible light. An example of the photopolymerization of an epoxide monomer with ambient solar irradiation is provided. Several other curcumin analogues were synthesized, and their use as photosensitizers is examined. With such photosensitizers, the range of spectral sensitivity can be extended well into the visible region of the electromagnetic spectrum. V
Journal of Polymer Science Part A: Polymer Chemistry, 2006
ABSTRACT
Journal of Polymer Science Part A: Polymer Chemistry, 2005
Studies of the onium salt photoinitiated cationic ring-opening polymerizations of various 3,3-dis... more Studies of the onium salt photoinitiated cationic ring-opening polymerizations of various 3,3-disubstituted oxetane monomers have been conducted with realtime infrared spectroscopy and optical pyrometry. The polymerizations of these monomers are typified by an extended induction period that has been attributed to the presence of a long-lived tertiary oxonium ion intermediate formed by the reaction of the initially formed secondary oxonium ion with the cyclic ether monomer. Because the extended induction period in the photopolymerization of these monomers renders oxetane monomers of limited value for many applications, methods have been sought for its minimization or elimination. Three general methods have been found effective in markedly shortening the induction period: (1) carrying out the photopolymerizations at higher temperatures, (2) copolymerizing with more reactive epoxide monomers, and (3) using free-radical photoinitiators as synergists. V
Journal of Macromolecular Science, Part A, 2012
Two benzotriazole derivatives, 2-benzyl-4,7-di(thiophen-2-yl)-2H-benzo[d][1,2,3]triazole (BBTS) a... more Two benzotriazole derivatives, 2-benzyl-4,7-di(thiophen-2-yl)-2H-benzo[d][1,2,3]triazole (BBTS) and 2-benzyl-4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2H-benzo[d] [1,2,3]triazole (BBTES) were employed as photosensitizers for diaryliodonium salt photoinitiators in photoinitiated cationic polymerization of various epoxide and vinyl ether monomers. Diphenyliodonium hexafluorophosphate (Ph2IPF6 ) salt was used as the photoinitiator in this study. Extended conjugation and electron-rich moieties of the photosensitizers enabled the use of long wavelength UV and visible light emitting
Progress in Organic …, 2011
The present paper is focused on visible light initiated cationic polymerizations. Photoinitiated ... more The present paper is focused on visible light initiated cationic polymerizations. Photoinitiated polymerization of representative vinyl ether and oxirane monomers using two quinoxaline derivatives; namely (2-(2,3-dihydrobenzo [b][1,4]dioxin-6-yl)-3-(2,3-dihydrobenzo[b]-[1,4]dioxin-7yl)-5-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-8-(2,3-dihydrothieno[3,4-b][1,4]dioxin-7yl) quinoxaline) (DBQEd) and 2,3,5,8-tetra(thiophen-2-yl)quinoxaline (TTQ) are studied. Novel dyes based on the quinoxaline skeleton are employed as efficient photosensitizers in cationic photopolymerizations. Polymerizations were initiated at room temperature upon irradiation with long-wavelength UV and visible lights in the presence of diphenyliodonium hexafluorophosphate (Ph 2 I + PF 6 −). The progress of the polymerizations was monitored by optical pyrometry (OP). Solar irradiation is also employed to carry out the cationic polymerization of a diepoxide monomer in the presence of air.
Journal of Polymer Science …, 2011
The use of two dibenzo[a,c]phenazine derivatives, 10,13-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5... more The use of two dibenzo[a,c]phenazine derivatives, 10,13-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)dibenzo[a,c]phenazine and 10,13-bis(4-hexylthiophen-2-yl)dibenzo[a,c]phenazine are reported as photosensitizers for diaryliodonium salt photoinitiators. Novel dyes based on the dibenzo[a,c]phenazine skeleton are shown to be efficient in carrying out the cationic photopolymerizations. Representative examples of different types of monomers including epoxide, and vinyl monomers are polymerized in the presence of the photosensitizers and diphenyliodonium hexafluorophosphate (Ph 2 I þ PF À 6). Polymer-izations are initiated at room temperature using long wavelength UV and visible light, and monitored by optical pyrometry. The photopolymerization of an epoxide monomer via solar irradiation is also demonstrated. V
Synthetic metals, 2005
Dual polymer electrochromic devices (ECDs) composed of electrochemically deposited conducting cop... more Dual polymer electrochromic devices (ECDs) composed of electrochemically deposited conducting copolymers of thiophene-functionalized monomers, 2-[(3-thienylcarbonyl)oxy] ethyl 3-thiophene carboxylate (TOET), 2,3-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOPT), and 3-[(3-thienylcarbonyl)oxy]-2,2-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOTPT), and polyethylene dioxythiophene (PEDOT) as the counter part were constructed with tetrabutylammonium tetrafluoroborate (TBAFB) doped gelled poly(methyl methacrylate) (PMMA) and evaluated. An electrochromic device with the following configuration was assembled-indium tin oxide (ITO)-coated glass /conducting copolymer || gel electrolyte || PEDOT/ITO. Spectroelectrochemistry, electrochromic switching, stability and open-circuit memory of the devices were examined.
![Research paper thumbnail of Synthesis, characterization and electrochromic properties of conducting copolymers of 2,3-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate with thiophene and pyrrole](https://attachments.academia-assets.com/81369418/thumbnails/1.jpg)
](European Polymer Journal, 2004
2,3-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOPT) was synthesized via the rea... more 2,3-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOPT) was synthesized via the reaction of 3-thionylcarboxylic acid with glycerol, and electrochemically polymerized either with thiophene and pyrrole by using tetrabutylammonium tetrafluoroborate (TBAFB) as the supporting electrolyte in acetonitrile (AN). Characterization of the resulting copolymers was performed via cyclic voltammetry, FTIR, thermal gravimetry analysis (TGA), and scanning electron microscopy (SEM). Electrical conductivities were measured by the
, 66 pages Synthesis of 2-[(3-thienylcarbonyl)oxy]ethyl 3-thiophene carboxylate (TOET), 2,3-bis-[... more , 66 pages Synthesis of 2-[(3-thienylcarbonyl)oxy]ethyl 3-thiophene carboxylate (TOET), 2,3-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOPT), and 3-[(3-thienylcarbonyl)oxy]-2,2-bis{[(3-thienylcarbonyl)oxy]}propyl 3thiophene carboxylate (TOTPT), and their copolymerization either with thiophene or pyrrole were achieved. The chemical structures of the monomers were investigated by Nuclear Magnetic Resonance Spectroscopy (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). Electrochemical behavior of the monomers and copolymers were studied by cyclic voltammetry (CV). The resultant conducting copolymers were characterized via FTIR, Thermal iv Gravimetry Analysis (TGA), Differential Scanning Calorimetry (DSC), and morphologies of the films were inspected by Scanning Electron Microscope (SEM). Conductivities of the samples were measured by using four-probe technique. The electrochromic and spectroelectrochemical properties of the copolymers were investigated.
Reactive & Functional Polymers, 2004
3-[(3-Thienylcarbonyl)oxy]-2,2-bis{[(3-thienylcarbonyl)oxy]}propyl 3-thiophene carboxylate (TOTPT... more 3-[(3-Thienylcarbonyl)oxy]-2,2-bis{[(3-thienylcarbonyl)oxy]}propyl 3-thiophene carboxylate (TOTPT) was synthesized by the reaction of 3-thionylcarbonyl chloride with pentaerythritol, it was electrochemically polymerized with either thiophene or pyrrole by using tetrabutylammonium tetrafluoroborate (TBAFB) as the supporting electrolyte in acetonitrile (AN). Characterization of the resulting copolymers was carried out by FTIR spectroscopy, cyclic voltammetry, thermal gravimetry analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Electrical conductivities of the copolymers were measured by the four-probe technique. The electrochemically synthesized copolymer was found to be capable of switching between an orange reduced state and a greenish-blue color oxidized state, and has an electronic band gap of 1.95 eV. The copolymer exhibited a long-term switching stability up to 400 double switches.
Journal of Applied Polymer Science
A novel benzenediamine-benzodithiophene polymer is synthesized for use in biosensor fabrication f... more A novel benzenediamine-benzodithiophene polymer is synthesized for use in biosensor fabrication for the detection of testosterone. The sensory platform is constructed via drop coating on a screen-printed carbon electrode, using poly(benzenediamine-Bis[(2-ethylhexyl)oxy]benzodithiophene) (pBDBT) as the polymer layer. Testosterone antibodies are immobilized on the polymercoated electrode surface via glutaraldehyde, which binds to the surface through the amino functional groups on the polymer backbone. The changes in the surface features due to testosterone binding are investigated via electrochemical techniques such as differential pulse voltammetry, cyclic voltammetry, and electrochemical impedance spectrometry as well as contact angle measurements. Surface morphology of the modified electrodes is characterized by atomic force microscopy. The linear range and limit of detection of the sensor are calculated. Impact of possible interfering compounds is investigated. Furthermore, the sensory platform is utilized for testosterone analysis in synthetic biological fluids.
Designed Monomers & Polymers
ABSTRACT
Polymer, 2013
ABSTRACT This article describes the use of functionalized quinoxaline derivatives as photosensiti... more ABSTRACT This article describes the use of functionalized quinoxaline derivatives as photosensitizers for diaryliodonium salt photoinitiators. Highly conjugated compounds with good absorption bands in long wavelength UV and visible region are presented. These versatile intermediates facilitate photoinitiated cationic polymerization of commercially important monomers such as cyclic ethers and vinyl epoxides. Polymerizations were carried out using long wavelength UV light in the presence of diphenyliodonium hexafluorophosphate (Ph2I+PF6-). The polymerizations were monitored by optical pyrometry (OP). In addition, we also demonstrate that it was also possible to initiate photopolymerizations under solar irradiation in the presence of these photosensitizers. (c) 2013 Elsevier Ltd. All rights reserved.
Macromolecules, 2005
ABSTRACT
Macromolecular Symposia, 2006
ABSTRACT
Journal of Polymer Science Part A: Polymer Chemistry, 2005
Curcumin, a naturally occurring, intensely yellow dye extracted from the spice turmeric, is an ef... more Curcumin, a naturally occurring, intensely yellow dye extracted from the spice turmeric, is an efficient photosensitizer for diaryliodonium salt photoinitiators at wavelengths ranging from 340 to 535 nm. With curcumin as a photosensitizer, it is possible to carry out the cationic photopolymerization of a wide variety of epoxide, oxetane, and vinyl monomers with long-wavelength UV and visible light. An example of the photopolymerization of an epoxide monomer with ambient solar irradiation is provided. Several other curcumin analogues were synthesized, and their use as photosensitizers is examined. With such photosensitizers, the range of spectral sensitivity can be extended well into the visible region of the electromagnetic spectrum. V
Journal of Polymer Science Part A: Polymer Chemistry, 2006
ABSTRACT
Journal of Polymer Science Part A: Polymer Chemistry, 2005
Studies of the onium salt photoinitiated cationic ring-opening polymerizations of various 3,3-dis... more Studies of the onium salt photoinitiated cationic ring-opening polymerizations of various 3,3-disubstituted oxetane monomers have been conducted with realtime infrared spectroscopy and optical pyrometry. The polymerizations of these monomers are typified by an extended induction period that has been attributed to the presence of a long-lived tertiary oxonium ion intermediate formed by the reaction of the initially formed secondary oxonium ion with the cyclic ether monomer. Because the extended induction period in the photopolymerization of these monomers renders oxetane monomers of limited value for many applications, methods have been sought for its minimization or elimination. Three general methods have been found effective in markedly shortening the induction period: (1) carrying out the photopolymerizations at higher temperatures, (2) copolymerizing with more reactive epoxide monomers, and (3) using free-radical photoinitiators as synergists. V
Journal of Macromolecular Science, Part A, 2012
Two benzotriazole derivatives, 2-benzyl-4,7-di(thiophen-2-yl)-2H-benzo[d][1,2,3]triazole (BBTS) a... more Two benzotriazole derivatives, 2-benzyl-4,7-di(thiophen-2-yl)-2H-benzo[d][1,2,3]triazole (BBTS) and 2-benzyl-4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2H-benzo[d] [1,2,3]triazole (BBTES) were employed as photosensitizers for diaryliodonium salt photoinitiators in photoinitiated cationic polymerization of various epoxide and vinyl ether monomers. Diphenyliodonium hexafluorophosphate (Ph2IPF6 ) salt was used as the photoinitiator in this study. Extended conjugation and electron-rich moieties of the photosensitizers enabled the use of long wavelength UV and visible light emitting
Progress in Organic …, 2011
The present paper is focused on visible light initiated cationic polymerizations. Photoinitiated ... more The present paper is focused on visible light initiated cationic polymerizations. Photoinitiated polymerization of representative vinyl ether and oxirane monomers using two quinoxaline derivatives; namely (2-(2,3-dihydrobenzo [b][1,4]dioxin-6-yl)-3-(2,3-dihydrobenzo[b]-[1,4]dioxin-7yl)-5-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-8-(2,3-dihydrothieno[3,4-b][1,4]dioxin-7yl) quinoxaline) (DBQEd) and 2,3,5,8-tetra(thiophen-2-yl)quinoxaline (TTQ) are studied. Novel dyes based on the quinoxaline skeleton are employed as efficient photosensitizers in cationic photopolymerizations. Polymerizations were initiated at room temperature upon irradiation with long-wavelength UV and visible lights in the presence of diphenyliodonium hexafluorophosphate (Ph 2 I + PF 6 −). The progress of the polymerizations was monitored by optical pyrometry (OP). Solar irradiation is also employed to carry out the cationic polymerization of a diepoxide monomer in the presence of air.
Journal of Polymer Science …, 2011
The use of two dibenzo[a,c]phenazine derivatives, 10,13-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5... more The use of two dibenzo[a,c]phenazine derivatives, 10,13-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)dibenzo[a,c]phenazine and 10,13-bis(4-hexylthiophen-2-yl)dibenzo[a,c]phenazine are reported as photosensitizers for diaryliodonium salt photoinitiators. Novel dyes based on the dibenzo[a,c]phenazine skeleton are shown to be efficient in carrying out the cationic photopolymerizations. Representative examples of different types of monomers including epoxide, and vinyl monomers are polymerized in the presence of the photosensitizers and diphenyliodonium hexafluorophosphate (Ph 2 I þ PF À 6). Polymer-izations are initiated at room temperature using long wavelength UV and visible light, and monitored by optical pyrometry. The photopolymerization of an epoxide monomer via solar irradiation is also demonstrated. V
Synthetic metals, 2005
Dual polymer electrochromic devices (ECDs) composed of electrochemically deposited conducting cop... more Dual polymer electrochromic devices (ECDs) composed of electrochemically deposited conducting copolymers of thiophene-functionalized monomers, 2-[(3-thienylcarbonyl)oxy] ethyl 3-thiophene carboxylate (TOET), 2,3-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOPT), and 3-[(3-thienylcarbonyl)oxy]-2,2-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOTPT), and polyethylene dioxythiophene (PEDOT) as the counter part were constructed with tetrabutylammonium tetrafluoroborate (TBAFB) doped gelled poly(methyl methacrylate) (PMMA) and evaluated. An electrochromic device with the following configuration was assembled-indium tin oxide (ITO)-coated glass /conducting copolymer || gel electrolyte || PEDOT/ITO. Spectroelectrochemistry, electrochromic switching, stability and open-circuit memory of the devices were examined.
European Polymer Journal, 2004
2,3-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOPT) was synthesized via the rea... more 2,3-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOPT) was synthesized via the reaction of 3-thionylcarboxylic acid with glycerol, and electrochemically polymerized either with thiophene and pyrrole by using tetrabutylammonium tetrafluoroborate (TBAFB) as the supporting electrolyte in acetonitrile (AN). Characterization of the resulting copolymers was performed via cyclic voltammetry, FTIR, thermal gravimetry analysis (TGA), and scanning electron microscopy (SEM). Electrical conductivities were measured by the
, 66 pages Synthesis of 2-[(3-thienylcarbonyl)oxy]ethyl 3-thiophene carboxylate (TOET), 2,3-bis-[... more , 66 pages Synthesis of 2-[(3-thienylcarbonyl)oxy]ethyl 3-thiophene carboxylate (TOET), 2,3-bis-[(3-thienylcarbonyl)oxy]propyl 3-thiophene carboxylate (TOPT), and 3-[(3-thienylcarbonyl)oxy]-2,2-bis{[(3-thienylcarbonyl)oxy]}propyl 3thiophene carboxylate (TOTPT), and their copolymerization either with thiophene or pyrrole were achieved. The chemical structures of the monomers were investigated by Nuclear Magnetic Resonance Spectroscopy (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). Electrochemical behavior of the monomers and copolymers were studied by cyclic voltammetry (CV). The resultant conducting copolymers were characterized via FTIR, Thermal iv Gravimetry Analysis (TGA), Differential Scanning Calorimetry (DSC), and morphologies of the films were inspected by Scanning Electron Microscope (SEM). Conductivities of the samples were measured by using four-probe technique. The electrochromic and spectroelectrochemical properties of the copolymers were investigated.