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    (2-fenil-1,3-dioksalan-4-il) metilmetakrilat'ın N-vinilpirolidon ve akrilonitril ile kopolimerlerinin sentezi ve karakterizasyonu
    (1998) Özdemir, Eyüp; Ahmedzade, Mısır; İlter, Zülfiye; Soykan, Cengiz; Ergin, Mehmet
    Bu çalışmada, gliserin, benzaldehit ve metakroilklorürden, yeni bir monomer, (2-fenil-l,3-dioksalan-4-il) metilmetakrilat elde edildi. Bu monomerin, 1,4-dioksanda benzoilperoksitin başlatıcı olarak kullanılmasıyla N-vinilpirolidon (N.VP) ve Akrilonitril (AN) ile kopolimerleri hazırlandı. Monomer ve kopolimerlerin karakterizasyonu İR, ^H-NMR ve ^C-NMR teknikleri ile yapıldı. Titrasyon yöntemiyle polimerlerin çözünürlük parametreleri tayin edildi. DSC (Diferansiyel Taramalı Kalorimetre) ile de termal özellikleri incelendi.
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    A new conducting polymer of 2,5-bis(2-thienyl)-1H-(pyrrole) (SNS) containing carbazole subunit: Electrochemical, optical and electrochromic properties
    (Elsevier Science Sa, 2009) Koyuncu, Sermet; Zafer, Ceylan; Sefer, Emre; Baycan Koyuncu, Fatma; Demiç, Şerafettin; Kaya, İsmet; Özdemir, Eyüp
    We report here the synthesis of a new electroactive monomer 3,6-di-tert-butyl-[4-(2,5-di-2-thienyl-1H-pyrrol-1-yl)phenyl]-9H-carbazole in five steps and polymerization of this monomer by two different procceses: Kumada Coupling and electro-oxidative. The product obtained by chemical polymerization exhibits a high thermal stability and narrow molecular weight distribution. While, in the UV-vis absorption spectrum of monomer the absorption peaks appear at 338 nm, the chemically synthesized polymer absorbs at 428 nm with 90 nm red shift. Cyclic voltammogram of monomer shows two separate oxidation processes which reflect the first oxidation at +0.84 V and a second one at +1.43 V. When the polymeric film prepared by electrochemical process was subjected to a repeated cyclic scan between -0.2V and +1.0V, it switches among three different colors (orange, green and blue). The oxidation and reduction response times were calculated as 2.0 s for this polymer film and exhibits high redox stability. The results anticipate that this kind of polymers can be used for designing electrochromics based on the use of one molecule for the generation of three basic colors (RGB). (C) 2009 Elsevier B.V. All rights reserved.
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    Determination of thermodynamic properties of poly (2-hydroxy ethyl methacrylate) at infinite dilution by using inverse gas chromatography
    (Freund Publishing House Ltd, 2000) Demirelli, Kadir; Kaya, İsmet; Özdemir, Eyüp
    Some thermodynamic quantities were obtained for the interactions of poly (2-hydroxy ethyl methacrylate) (PHEMA) with alcohols, ketones, acetates, aromatics and n-alkanes by the inverse gas chromatography method in the temperature range of 130-150 degreesC. The specific retention volumes, Vg degrees, weight fraction activity coefficients of solute probes at infinite dilution, Omega (infinity)(1) Flory-Huggins thermodynamic interaction parameters, chi (infinity)(12), between polymers and solvents, the partial molar free energy, DeltaG(1)(infinity), the partial molar heat of mixing, DeltaH(1)(infinity), were determined. All the liquids were found to be nonsolvents for poly (2-hydroxy ethyl methacrylate) at 130-150 degreesC. The solubility parameters for PHEMA at infinite dilution were found by plotting the graph of [(delta (2)(1)/RT) - chi (infinity)(12)/VI] versus solubility parameters, delta (1), of these probes. The solubility parameter values of PHEMA found from both the slope and intercept in Fig. 2 are 6.24 (cal/cm(3))(0.5) and 7.08 (cal/cm(3))(0.5) at 140 degreesC.
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    Electrochemical and optical properties of novel donor-acceptor thiophene-perylene-thiophene polymers
    (Wiley, 2008) Koyuncu, Sermet; Kuş, Mahmut; Demiç, Şerafettin; Kaya, İsmet; Özdemir, Eyüp; İçli, Sıddık
    In this study, donor-acceptor type thiophene-perylene-thiophene monomers were synthesized and polymerized by both oxidative polymerization using FeCl3 as catalyst and the electrochemical process. UV-vis, FTIR, H-1 NMR, and elemental analysis techniques were used for structural characterization. Thermal behaviors of these compounds were determined by using TGA system. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels and electrochemical and optical band gap values were calculated by using the results of cyclic voltammetry and UV-vis measurements, respectively. The number-average molecular weight (M-n), weight-average molecular weight (M-n), and polydispersity index (PDI) values of synthesized polymers were determined by size exclusion chromatography. Conductivity measurements of these polymers were carried out by electrometer by using a four-point probe technique. The conductivity was observed to be increased by iodine doping. (C) 2008 Wiley Periodicals, Inc.
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    Electrochemical, optical and electrochromic properties of imine polymers containing thiophene and carbazole units
    (Elsevier Science Sa, 2009) Koyuncu, Sermet; Kaya, İsmet; Baycan Koyuncu, Fatma; Özdemir, Eyüp
    New imine polymers containing thiophene and carbazole moiety were synthesized by using both chemically oxidative in the presence of FeCl3 and electrochemically oxidative process. While UV-vis, FT-IR, H-1- and C-13 NMR techniques were used for the structural characterization, the number-average molecular weight (M-n), weight-average molecular weight (M-w) and polydispersity index (PDI) values were determined by size exclusion chromatography (SEC). The highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energy levels, electrochemical (E-g') and optical band gap (E-g) values were calculated by using the results of cyclic voltammetry and UV-vis absorption spectroscopy measurements, respectively. Spectroelectrochemical measurements were carried out against the changes in the optical properties of conducting polymers upon voltage changed. Also the yellow color of film changed to green color with applied potential. Conductivities of these polymers were determined by using four-point probe technique. It was seen that the conductivities were increased by iodine doping. (C) 2009 Elsevier B.V. All rights reserved.
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    Schiff bazı sübstitüentli oligofenollerin sentezi ve karakterizasyonu
    (2003) Kaya, İsmet; Şenol Bahçeci, Dilek; Koyuncu, Sermet; Özdemir, Eyüp
    Bu çalışmada, 2-aminofenol, 3-aminofenol, 4-aminofenol ile benzaldehit'in reaksiyonundan Schiff bazları elde edildi. Daha sonra oligo fenollerle NaOCl, $H_2O_$2 ve hava oksijenin oksidatif polikondenzasyon reaksiyon şartlan ve onların ürünleri incelendi. Schiff bazı sübstitüentli oligo fenoller alkali ortamda 50-100°C arasında 2-aminofenol, 3-aminofenol, 4-aminofenol ile benzaldehit'in oksidadif polikondenzasyonundan sentezlendi. Sentezlenmiş ürünlerin yapıları element analizi, FT-IR, $^1H-NMR$, $^{13}C-NMR$ ve UV-Vis spektrumlarındaki verilerinden faydalanarak belirlendi. O-2-HFBA-I, O-2-HFBA-II, O-3-HFBA ve O-4-HFBA'mn büyüklükçe ayırma kromatografısi analizleri (SEÇ) göre, sayıca ortalama molekül ağırlığı $(M_n)$, ağırlıkça ortalama molekül ağırlığı $(M_w)$ ve polidispersiti indeksi (PDI) değerleri sırasıyla 2166 g $mol^{-1}$, 2591 g $mol^{-1}$, 1,196; 1736 g $mol^{-1}$, 2509 g $mol^{-1}$, 1,445; 2372 g $mol^{-1}$, 4722 g $mol^{-1}$, 1,990 ve 2155 g $mol^{-1}$, 4164 g $mol^{-1}$ ve 1,737 olarak bulundu. Ayrıca, DTA ve TG analizleri oligo-2-hidroksifenilbenzaldimin (O-2-HPBA),oligo-3-hidroksifenilbenzaldimin (O-3-HPBA) ve oligo-4-hidroksifenilbenzaldimin (O-4-HPBA) thermo-oksidatif bozunmaya karşı kararlı olduklarını gösterdi. O-2-HPBA. O-3-HPBA ve O-4-HPBA'nın 1000°C'deki kütle kayıpları sırasıyla %93,63, %59,46 ve %95,87 olarak bulundu. Buna ilaveten, epoksi-oligomer blend karışımlarının termal özellikleri incelendi. Epoksi-oligomer blend karışımının 1000°C'deki kütle kaybı %55 olarak bulundu.
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    Synthesis, characterization and thermal degradation of oligo-2-[(4- iodophenylimino)methyl|phenol and ol1gomer-metal complexes
    (2009) Kaya, İsmet; Moral, Fatma; Özdemir, Eyüp
    The conditions for oxidative condensation of 2-[(4-iodophenylimino)methyl] pheno| (1P1MP) were studied with air and NaOCI as oxidants in an aqueous alkaline medium between 50 and 90°C. Size exclusion chromatography (SEC) showed that the number-average molecular weight (Mn), weight-average molecular weight (Mw) and polydispersity index (PDI) values, respectively, were 1250, 1300 g mol-1 and 1.040 for oxidation with NaOCI and 2200, 2500 g mol-1 and 1.136 for oxidation by air. With the optimum reaction conditions, the yield of OIPIMP was found to be 67 % with NaOCI, and 29 % with air, as oxidant. The OIPIMP was characterized by 1H-NMR, 13C-NMR, FT-1R, UV-Vis and elemental analysis. Metal complexes of the oligomerwere shown to be more thermally stable than OIPIMP itself. © 2009 Chemical Society of Ethiopia.
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    SYNTHESIS, CHARACTERIZATION AND THERMAL DEGRADATION OF OLIGO-2-[(4-IODOPHENYLIMINO)METHYL]PHENOL AND OLIGOMER-METAL COMPLEXES
    (Chem Soc Ethiopia, 2009) Kaya, İsmet; Moral, Fatma; Özdemir, Eyüp
    The conditions for oxidative condensation of 2-[(4-iodophenylimino)methyl]phenol (IPIMP) were studied with air and NaOCI as oxidants in an aqueous alkaline medium between 50 and 90 degrees C. Size exclusion chromatography (SEC) showed that the number-average molecular weight (M(n)), weight-average molecular weight (M(w)) and polydispersity index (PDI) values, respectively, were 1250, 1300 g mol(-1) and 1.040 for oxidation with NaOCI and 2200, 2500 g mol(-1) and 1.136 for oxidation by air. With the optimum reaction conditions, the yield of OIPIMP was found to be 67 % with NaOCI, and 29 % with air, as oxidant. The OIPIMP was characterized by (1)H-NMR, (13)C-NMR, FT-IR, UV-Vis and elemental analysis. Metal complexes of the oligomer were shown to be more thermally stable than OIPIMP itself.
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    Synthesis, characterization, and kinetic study of functional polystyrenes
    (John Wiley & Sons Inc, 2007) Doğan, Fatih; Kaya, İsmet; Dayan, Osman; Özdemir, Eyüp
    In this study, functionalization of polystyrene (PS) (M,, = 2.5 X 105) was carry out with maleic anhydride in the presence of boron trifluoride dietyhletherade (BF3 OEt2) as catalyst and then functional PS was subjected to condensation reaction with phenyl hydrazine. The structures of both of them were determined by using FTIR, H-1-NMR, elemental analysis, thermogravimetric analysis (TGA) and differential thermal analysis (DTA) techniques. Some physical properties of these two products were investigated and the kinetic parameters of solid state decomposition reactions were determined from TGA curves. The intrinsic viscosity [eta] values of modified PS and condensation products (cPs) found to be 1.024 and 0.7036 dL g(-1) respectively. According to TGA, the weight losses of modified PS and cPs were found to be 84.03 and 81.86%, respectively, at 500 degrees C. (c) 2007 Wiley Periodicals, Inc.
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    Synthesis, characterization, and thermal degradation of oligo-2-[(4-chlorophenyl) imino methylenel phenol and its oligomer-metal complexes
    (Taylor & Francis Inc, 2005) Kaya, İsmet; Kızılkaya, Bayram; Özdemir, Eyüp
    The oxidative polycondensation reaction conditions of 2-[(4-chlorophenyl) imino methylene] phenol (CPIMP) were studied by air O-2 and NaOCl oxidants at various temperatures and times. Optimum reaction conditions of air O-2 and NaOCl were determined for CPIMP. Oligo-2-[(4-chlorophenyl) imino methylene] phenol (OCPIMP) was synthesized from the oxidative polycondensation of CPIMP with air O-2 and NaOCl in alkaline medium between 50 and 90 degrees C. The number-average molecular weight (M-n) weight-average molecular weight (M-n) and polydispersity index (PDI) values of OCPIMP were found to be 470 g mol(-1), 895 g mol(-1), and 1.90, using NaOCl, and 455 g mol(-1), 765 g mol(-1), and 1.68, using air O-2, respectively. At the optimum reaction conditions, the yield of OCPIMP was found to be 62.80% (for air O-2 oxidant) and 87.50% (for NaOCl oxidant). The OCPIMP was characterized by H-1-NMR, FT-IR, UV-Vis and elemental analysis. The thermogravimetric (TGA)-DTA analyses were shown to be stable of OCPIMP and its oligomer metal complexes (such as Co+2, Ni+2, and Cu+2) against thermo-oxidative decomposition. The weight loss of OCPIMP and its oligomer metal complexes (such as Co+2, Ni+2, and Cu+2) were found to be 98%, 85%, 80%, and 82%, respectively, at 1000 degrees C.
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    Synthesis, characterization, optimum reaction conditions, and some polymer-metal complexes of poly(phenoxy-imine)s containing furan ring
    (Springer, 2018) Kaya, İsmet; Orta, İbrahim Erdem; Özdemir, Eyüp; Şenol, Dilek
    In this study, Schiff bases containing azomethine (-HC=N-) compounds were synthesized from the condensation reaction of 4-aminophenol and 2-aminophenol and 5-methyl-2-furaldehyde. Orange-colored Schiff bases, 4-[(5-methyl- 2-furyl) methyleneamino] phenol (4MFMAP) and 2-[(5-methyl-2-furyl) methyleneamino] phenol (2MFMAP) turned to poly-4-[(5-methyl-2-furyl) methyleneamino] phenol (P-4MFMAP) and poly-2-[(5-methyl-2-furyl) methyleneamino] phenol (P-2MFMAP) polyazomethine derivatives by NaOCl oxidant in alkaline aqueous medium. In addition, poly-2-[(5-methyl-2-furyl) methyleneamino] phenol cobalt (II) and copper (II) complexes were synthesized. FTIR and NMR measurements for structural analysis of the synthesized compounds, UV-Vis analysis for optical properties, electrical conductivity measurements, and thermal analysis with the TG-DTA techniques were determined. The yield of P-4MFMAP and P-2MFMAP was found to be 84.6% and 78.6 as follows [4MFMAP] = 0.066, [KOH] = 0.198 [NaOCl] = 0.066 mol L-1 at 60 A degrees C for 3 h and [2MFMAP] = 0.066, [KOH] = 0.132 [NaOCl] = 0.066 mol L-1 at 70 A degrees C for 3 h, respectively.
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    The oxidative polycondensation of 4-[(Phenylimino)methyl] phenol using NaOCl, air oxygen, and H2O2 at alkaline and neutral medium
    (Taylor & Francis Ltd, 2006) Kaya, İsmet; Karayiğitler, Halil; Özdemir, Eyüp
    In this study, the oxidative polycondensation reaction conditions of 4-[(phenylimino) methyl] phenol (4-PIMP) with air oxygen, H2O2 , and NaOCl oxidants in aqueous alkaline and neutral medium between 50 degrees and 90 degrees C were examined. 4-PIMP and its condensation product, oligo-4-[(phenylimino) methyl] phenol (O-4-PIMP), were characterized by H-1-C-13-NMR, FT-IR, UV-vis techniques, and elemental analysis. At the optimum reaction conditions, the yield of oligo-4-[(phenylimino) methyl] phenol was found to be 73% for NaOCl, 65% for air O-2 , and 70% for H2O2 . According to size exclusion chromatography (SEC) analyses, the number-average molecular weight (M n ), weight-average molecular weight (M w ), and polydispersity index (PDI) values of O-4-PIMP were 5268, 10320 g mol(-1) , and 1.959, respectively, using air O 2 ; 8215, 17789 g mol(-1) , and 2.165, respectively, using NaOCl; and 4800, 5260 g mol(-1) , and 1.096, respectively, using H2O2. The carbon residues for 4-PIMP and O-4-PIMP were found to be 42.4% and 53.4%, respectively, at 1000 degrees C by using TG-DTA analyses.