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    6-Hydroxyquinoline Oligomers Emit White Light
    (Amer Scientific Publishers, 2014) Doğan, Fatih; Bilici, Ali; Yıldırım, Mehmet; Kaya, İsmet
    The 6-hyroxyquinoline (HQ) was shown to undergo an oxidative oligomerization reaction in the alkaline medium. The obtained oligo (6-hyroxyquinoline) (OHQ) was characterized with respect to chemical composition, molecular weight, particle size, thermal stability, morphology and conductivity. FT-IR and H-1-NMR spectral data suggested that the resulting product was mainly C2, C4 and C6-coupled via C-C/C-O-C linkages. OHQ emitted white light upon irradiated at 339 nm. Optical band gap (E-g) of OHQ was determined to be 2.78 eV. The isolated product was amorphous and soluble in common polar organic solvents. The solid state conductivity studies for OHQ were also performed and found to be in the region of semiconductor.
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    A Kinetic Evaluation for PANSA Doped Low Density Polyethylene Blends
    (2019) Doğan, Fatih; Bilici, Ali; Kaya, İsmet; Şirin, Mehtap
    In our previous study, we prepared blends of lowdensity polyethylene (LDPE) with semiconductorpolymer, poly (1-amino-2-hydroxynaphthalene-4-sulfonic acid) (PANSA), in different mixing ratios. Inthat study, the findings on some physical and chemical properties of the blends prepared were alsopresented. In this study, it was aimed to investigate the thermal decomposition kinetics of these preparedblends. For this purpose, thermograms of PANSA doped LDPE blends at four different heating rates wereobtained. With the addition of PANSA into LDPE, it was observed that the initial decompositiontemperature and maximum decomposition temperature of LDPE increased. Thermal decompositionkinetics of blends were performed using the integral isoconversional methods (Kissinger, Kim-Park (KP),Tang, Kissenger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO)) in addition to differentialisoconversional method (Friedman method). The activation energy values calculated by Kissinger, KP,Tang, KAS, FWO and Friedman methods and found to be 187.9, 200.2, 171.90, 171.78, 171.70 and171.89 kJ mol-1for 0.5 % PANSA doped LDPE, 193.9, 206.2, 173.31, 172.87, 172.98 and 172.78 kJmol-1for 1 % PANSA doped LDPE and 207.0, 219.2, 196.94, 197.09, 198.08 and 208.10 kJ mol-1for 0.5% PANSA doped LDPE, respectively. Thermal decomposition mechanism for blends was proposed withthe help of master plot curves.
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    A Kinetic Evaluation for Phenothiazine Based Copolymers
    (2021) Doğan, Fatih
    In here, the nonisothermal decomposition kinetics of co-polymers based phenothiazine was present-ed. For this, firstly, 3, 7-di-2-thienyl-10H-phenothiazine (TF) was prepared via an optimized Suzu-ki–Miyaura cross-coupling reaction. After monomer (TF) characterization, the copolymerization re-actions with EDOT and thiophene were performed by the electrochemical technique. The molecular masses of the co-polymers were found by gel permeation chromatography (GPC) analysis. Thermal characterizations of the resulting polymers were conducted by thermogravimetric analyses. The thermal decomposition kinetics of the resulting polymers was also performed. For this, the kinetic methods (Tang, FWO, KAS, Kissinger, and Friedman) based on the multiple heating rates were used. Several kinetic parameters related to the decomposition kinetics of the solid-state were revealed.
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    A New Schiff Base Epoxy Oligomer Resin: Synthesis, Characterization, and Thermal Decomposition Kinetics
    (Wiley, 2011) Kaya, İsmet; Doğan, Fatih; Gul, Murat
    Oligo{2,20-{1,4-phenylenebis[nitrilomethylylidene]} bis(6-methoxyphenol)} (OPNMMP) was synthesized from o-vanillin and p-phenylene diamine by oxidative polycondensation with NaOCl in an aqueous alkaline. Then, a new Schiff Base epoxy oligomer resin, OPNMMP-epichlorohydrine (EPC), was produced with EPC. The structures of the resulting compounds were confirmed by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, H-1-NMR, and C-13-NMR. Further characterization processes were preformed by thermogravimetry (TG)-differential thermal analysis, gel permeation chromatography, and solubility testing. Also, the kinetics of the thermal decomposition of OPNMMP-EPC were investigated by thermogravimetric analysis. The TG curves showed that the thermal decomposition of OPNMMP-EPC occurred in one stage. The kinetic parameters related to the decomposition kinetics of OPNMMP-EPC were obtained from TG curves with the following methods: Friedman, Flynn-Wall-Ozawa, Kissinger, invariant kinetic parameter, and Coats-Redfern (CR), under an N-2 dynamic atmosphere and different heating rates (5, 10, 15, and 20 degrees C/min). The mechanism function and pre-exponential factor were also determined by a master plots method. The apparent activation energies of the thermal decomposition were calculated from these methods for OPNMMP-EPC. The analysis of the results obtained by the CR and master plots methods showed that the decomposition mechanism of OPNMMP-EPC in N-2 was a deceleration-type mechanism. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 3211-3222, 2011
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    A novel shape-controlled synthesis of bifunctional organic polymeric nanoparticles
    (Elsevier Sci Ltd, 2015) Doğan, Fatih; Temizkan, Kevser; Kaya, İsmet
    A novel shape-controlled bifunctional organic nanoparticle was reported using the facile synthesis of self-stabilized monohydroxy amino naphthol nanoparticles. For this purpose, bifunctional monomer was polymerized by NaOCl as oxidant in aqueous alkaline medium at 70 degrees C. These poly-nanoparticles with molecular weight ca. 5000 Da was obtained by template-free oxidative polymerization (OP) process. The structure of polymer was confirmed by NMR, FT-IR, UV-Vis and X-RD measurements. The chemical and physical properties of polymer were determined size exclusion chromatography (SEC), thermogravimetry (TG), differential scanning calorimetry (DSC), cyclic voltammetry (CV), photoluminescence (PL), dynamic light scattering (DLS), scanning electron microscope (SEM), transmission electron microscope (TEM) and conductivity techniques. The SEM analysis of polymer indicated to be had a nanoparticle structure. The reversible redox behavior of the polymer was attributed to its electroactive nature. In addition, the kinetic parameters related to the solid state decomposition of the poly-nanoparticles were calculated by non-isothermal methods based on multiple heating rates. (C) 2015 Elsevier Ltd. All rights reserved.
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    Artırılmış Gerçeklik Uygulamalarının 6. sınıf Öğrencilerinin Hücre Konusundaki Akademik Başarılarına Etkisi
    (2019) Timur, Serkan; Doğan, Fatih; Çetin, Nagihan İmer; Timur, Betül; Işık, Rüveyda
    Bu çalışmada artırılmış gerçeklik (AG) uygulamalarının altıncı sınıf öğrencilerinin Fen Bilimleri dersiöğretim programında yer alan “Hücre” konusundaki akademik başarılarına etkisi araştırılmıştır. Araştırma öntest-son test tek gruplu yarı deneysel desen şeklinde gerçekleştirilmiştir. Araştırmanın örneklem grubunu 2017-2018 öğretim yılı Ankara ilinde öğrenim gören ve tesadüfi örneklem tekniği ile belirlenen 76 altıncı sınıföğrencisi oluşturmuştur. Çalışmanın deneysel sürecinde dersler soru-cevap, düz anlatım ve gerektiği durumlardaAG uygulamaları kullanılarak işlenmiştir. Araştırmada ön test ve son test olarak Timur vd. (2019) tarafındangeliştirilen “Hücre Başarı Testi (HBT)” kullanılmıştır. HBT testinden elde edilen verilerin analizi sonucunda öntest ve son test arasında istatistiksel olarak anlamlı bir farklılık bulunmuştur. Elde edilen puanların AGuygulamalarının önemli rolünden dolayı son test lehine arttığı görülmüştür. Bu çalışmada AG uygulamalarınınöğrencinin başarısını olumlu yönde etkilediği sonucuna ulaşılmıştır ve bu sonuç, AG uygulamalarının dersteöğrenci motivasyonunu artırması ve öğrencinin dersteki dikkat süresini uzatması ile ilişkili olabileceği şeklindeyorumlanmıştır. AG uygulamaları eğitim alanında henüz kullanılan teknolojilerden olduğundan ileridekiçalışmalarda bu teknolojilerin eğitimle ilişkisi farklı değişkenler açısından incelenebilir.
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    Ayarlanabilir ve Çoklu Renk Emisyonu Verebilen Kinolin Polimerlerin Sentezleri Ve Karakterizasyonlari
    (2015) Bilici, Ali; Doğan, Fatih; Özay, Özgür
    Yapılan çalışmada, amino kinolin monomerlerinin farklı oksidantlar vasitasıyla oksidatif polimerizasyonları gerçekleştirildi. Polimerizasyonlar için reaksiyon şartları incelendi. Sentezlenen kinolin polimerlerinin karakterizasyonu UV-Vis, FT-IR, NMR, GPC, SEM, XRD, XPS, CV, floresans, AFM, SEM, TEM ve iletkenlik analizleri ile belirlendi. Farklı dalga boylarında uyarılan polimer çözeltilerinin emisyon karakterleri incelendi. 6AQP-Cu’ın farklı çözücülerde farklı renk emisyonları verdiği, 5AQP’nin ise farklı dalga boylarıda uyarıldığında çoklu renk emisyonu verdiği belirlendi. Elde edilen ürünlerin ısısal stabiliteleri TG/DTG-DTA ve DSC ölçümleri ile tayin edildi. Çalışmanın son aşamasında sentezlenen ürünlerin ısısal katı hal bozunma kinetikleri farklı sınıflara ait bir çok yöntem kullanılarak hesaplandı. Sentezlenen maddelerin bozunma basamaklarına ait matematiksel fonksiyonlar belirlendi. Polimerizasyon ürünlerinin diffüzyon tipi (Dn) mekanizma ile bozunduğu belirlendi.
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    Azomethine-based phenol polymer: Synthesis, characterization and thermal study
    (Elsevier Science Sa, 2011) Doğan, Fatih; Kaya, İsmet; Bilici, Ali
    Azomethine-based phenol polymer, poly-2-{[(6-aminopyridin-2-yl)imino]methyl}-phenol (PAPIMP), was synthesized through the combination of condensation reaction and oxidative polymerization. Polymer isolated from aqueous solution was characterized by UV-vis, FT-IR, NMR and TG, SEC analysis. According to the SEC chromatograms, the number-average molecular weight (M(n)), weight-average molecular weight (M(w)) and polydispersity index (PDI) values of PAPIMP were determined to be 33,550, 78,900 g mol(-1) and 2.352, respectively. Also, optical band gaps (E(g)) of APIMP and PAPIMP calculated from cyclic voltammetry (CV) measurements. Also, electrical conductivities of each component measured with four-point probe technique. TG analysis showed that PAPIMP was stable up to 300 degrees C. The thermal decomposition kinetics of PAPIMP was investigated by means of thermogravimetric analysis in dynamic nitrogen atmosphere at four different heating rates: 5, 10, 15 and 20 degrees C min(-1) The apparent activation energies for thermal decomposition of PAPIMP were obtained by Tang, Flynn-Wall-Ozawa (FWO), Kissenger-Akahira-Sunose (KAS) and Coats-Redfern methods (CR) were 96.97, 105.33, 97.28 and 88.60 kJ mol(-1), respectively; the mechanism function and pre-exponential factor were determined by master plots method. The most likely decomposition process was a D(n) Deceleration type in terms of the Coats-Redfern and master plots results. (C) 2010 Elsevier B.V. All rights reserved.
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    Catalytic Oxidation of 2,7-Dihydroxynaphthalene
    (Amer Chemical Soc, 2014) Bilici, Ali; Doğan, Fatih; Kaya, İsmet
    Two polymer-metal complexes were used for catalytic oxidative polymerization of 2,7-dihydroxynaphthalene (DHN) with the aim of exploiting new and potent catalysts. The structure of the resulting poly(2,7-dihydroxynaphthalene) (PDHN) was confirmed by various spectral techniques: UV-vis, FT-IR, H-1 NMR, C-13 NMR, H-1-H-1 COSY, and H-1-C-13 HSQC. The 3 and 6 positions of the DHN ring were suggested as main coupling sites. The effect of the reaction conditions on the monomer conversions and the polymer molecular weight was determined: yields in the range 74-99% and number-average molecular weights in the range 1700-83 000 g mol(-1) were obtained. Thermal, optical, and electrochemical behaviors of the polymer were also studied. From fluorescence analyses, a case of negative solvatochromism for PDHN was established.
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    Chemical oxidative polymerization, optical, electrochemical and kinetic studies of 8-amino-2-naphthol
    (Springer, 2015) Doğan, Fatih; Kaya, İsmet; Bilici, Ali; Yıldırım, Mehmet
    Here the polymerization of 8-amino-2-naphthol (AN) is reported without use of an additional external template, surfactants or functional dopants. For this, NaOCl and hydrochloride acid solution (1.0 M) were used as oxidant and reaction medium, respectively. The structure of oligomer was elucidated by FT-IR, UV-vis and H-1-NMR techniques. The number average molecular weight of oligomer was found to be 2200Da with a polydispersity index of 1.4 by size exclusion chromatography. This oligomer exhibited a multicolor emission behavior as it was excited at different wavelenghts. Redox states were clarified by cyclic voltammetry (CV) technique and the relationship between anodic/cathodic peak currents vs. scan rates was determined. Thermal analysis and XRD data assigned that the resulting oligomer was in a semi-crystalline form. The activation energy related to the solid state decomposition was calculated from differential and integral non-isothermal methods and the lowest value using Kissinger procedures was determined to be 79.53 kJ/mol in N-2 atmosphere.
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    Chemical Oxidative Synthesis and Characterization of Poly(8-hydroxyquinoline) Particles
    (Taylor & Francis Inc, 2014) Doğan, Fatih; Kaya, İsmet; Temizkan, Kevser
    The chemical oxidative polymerization (OP) of 8-hydroxyquinoline (HQ) in an organic medium leaded to the formation of the C-2 and C-4 linking poly (8-hydroxyquinoline) (PHQ). The structure of PHQ was confirmed by UV-Vis, FT-IR, and H-1-NMR. The characterization of polymer was performed by TG-DTA, differential scanning calorimetry, dynamic mechanical analysis, dynamic light scattering, size exclusion chromatography, X-ray diffraction, cyclic voltammetry, atomic force microscope, photoluminescence and solubility tests. The fluorescence spectrum of PHQ exhibited an emission peak at approximately 525nm in DMSO. Accordingly, it was found PHQ emitted green light whereas HQ emitted yellow light in DMSO solvent. Optical band gaps (E-g) of PHQ was calculated to be 3.31eV. The electrical conductivities of iodine doped-PHQ and undoped-PHQ were measured with four-point probe technique. Magnetic particles was prepared by chemical precipitation of mixed Fe(II) and Fe(III) salts and modified with HQ by using an in situ chemical oxidation polymerization method in organic medium.
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    Conducting polymer composites based on LDPE doped with poly(aminonaphthol sulfonic acid)
    (Elsevier Science Bv, 2018) Doğan, Fatih; Sirin, Kamil; Kolcu, Feyza; Kaya, İsmet
    The paper presents the mechanical, morphological, thermal and the electrostatic charge dissipative (ESD) properties of binary blends of low-density poly (ethylene) (LDPE) blended with poly (1-amino-2-hydroxy naphthalene-4-sulfonic acid) (PANSA). Blends were prepared by loading 0.5, 1.0 and 3 wt% of PANSA into LDPE matrix in the twin-screw micro extruder. The interaction between PANSA and LDPE was then characterized by FT-IR, DSC, TG, DMA, AFM, SEM and X-RD techniques. The resulting polyolefin-based blends were also investigated by stress-strain curves in order to analyze some physico-mechanical properties. Percentages of the crystallinity of the blends were calculated by FT-IR, DSC and X-RD analyses. The conductivity of PANSA/LDPE blends was determined to be in the range of 10(-11) - 10(-12) S cm(-1) using ESD applications. The antistatic decay time of blend films was found to be of the order of 0.103-1.721 secat corona voltages between -3 kV and 3 kV, concluding that PANSA can be used as an effective ESD material for antistatic coatings of LDPE.
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    Determination of Attitudes of Preservice Teachers Towards Laboratory Practices
    (Çanakkale Onsekiz Mart Üniversitesi, 2014) Karatay, Ramazan; Doğan, Fatih; Şahin, Çavuş
    This study aims to determine the attitudes of preservice teachers towards laboratory practices. The participants of the study, conducted by means of screening model, were preservice teachers of Science and Classroom Teaching; and “Attitude Scale towards Laboratory Practices” of 69-item Likert-type was utilized in the study. The sample of the study was composed of 216 preservice teachers. The data obtained were examined descriptively; and t-Test was utilized for the relations between the data and variables. The attitudes of the preservice teachers towards laboratory practices were found to be positive in general. When the subdimensions of the scale were analyzed, it was found that the attitudes towards the general goals and permanence of laboratory practices as well as towards the reports or notes were high. However, the attitudes towards the preparations, manuals, processing, and physical conditions of laboratory practices were found to be lower. In respect to the sub-problems analyzed, the attitudes towards laboratory practices were found out not to show any significant change in terms of the gender and the departments of preservice teachers.
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    Developing an Achievement Test about 7th Grade “Solar System and Beyond” Unit: Analysis of Validity and Reliability
    (2020) Doğan, Fatih; Özdemir, Burcu
    The aim of this research is to develop a reliable and valid achievementtest to measure academic success of pupils about 7th grade’s ‚SolarSystem and Beyond? unit. For this reason, depending on the objectivesof ‚Solar System and Beyond? unit, which is included in middle schoolscience program, which was published in 2018, 42 multiple-choice testquestions were prepared. The clearness of the test questions, cohesionwith the objectives and scientific knowledge were designed with thecare of various sights of the authorities in teaching science field whichdepend on the technic which was suggested by Lawshe (1975).According to this, content validity score was calculated as .94. The pilotstudy for this test put into practice with 254 students who had studied7th grade in 2018-2019 academic years. As a consequence of the itemstatistic which was realized in the process of test development by theanswers of the students for each question, difficulty score and itemdiscrimination were calculated for each of the item. As a consequenceof item statistic, 8 items were excluded from the test and the last formof the ‚Solar System and Beyond Academic Achievement Test? wasdesigned with 35 questions. As a result of the analysis, the last form’sKR-20 reliability co-efficient was calculated as .87. Average itemdifficulty index was calculated as .61 and average item discriminationindex was calculated as .48. According to this outcome, average itemdifficulty was identified as midlevel, and average item discriminationwas identified as high-level.
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    Effect of CaCO3 Filler Component on Solid State Decomposition Kinetic of PP/LDPE/CaCO3 Composites
    (Taylor & Francis Inc, 2009) Sirin, Kamil; Doğan, Fatih; Balcan, Mehmet; Kaya, İsmet
    In this study, the effect of addition Calcium carbonate (CaCO3) filler component on solid state thermal decomposition procedures of Polypropylene-Low Density Polyethylene (PP-LDPE; 90/10 wt%) blends involving different amounts (5, 10, 20 wt%) Calcium carbonate (CaCO3) was investigated using thermogravimetry in dynamic nitrogen atmosphere at different heating rates. An integral composite procedure involving the integral iso-conversional methods such as the Tang (TM), the Kissinger-Akahira-Sunose method (KAS), the Flynn-Wall-Ozawa (FWO), an integral method such as Coats-Redfern (CR) and master plots method were employed to determine the kinetic model and kinetic parameters of the decomposition processes under non-isothermal conditions. The Iso-conversional methods indicated that the thermal decomposition reaction should conform to single reaction model. The results of the integral composite procedures of TG data at various heating rates suggested that thermal processes of PP-LDPE-CaCO3 composites involving different amounts of CaCO3 filler component (5, 10, 20 wt%) followed a single step with approximate activation energies of 226.7, 248.9, and 252.0 kJ.mol- 1 according to the FWO method, respectively and those of 231.3, 240.1 and 243.0 kJ mol- 1 at 5 degrees C min- 1 according to the Coats-Redfern method, the reaction mechanisms of all the composites was described from the master plots methods and are Pn model for composite C-1, Rn model for composites C-2 and C-3, respectively. It was found that the thermal stability, activation energy and thermal decomposition process changed by the increasing CaCO3 filler weight in composite structure.
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    Elektro-Aktif Flu?oresant Polimerlerin Poliolefin Temelli Malzemelerde Antistatik Materyal Olarak Kullanımı
    (2016) Doğan, Fatih; Bilici, Ali; Şirin, Kamil
    Bu çalı?mada sulfoaminonaftol monomerlerinin sulu (asidik veya bazik) ve organik ortamlarda uygun oksidantlar e?liğinde oksidatif polimerizasyonları gerçekle?tirildi. Polimerizasyonların optimum reaksiyon ?artları incelendi. Sentezlenen polimerlerin karakterizasyonu UV-vis, FT-IR, NMR, SEC, SEM, TEM, DLS, X-RD, PL, AFM ve iletkenlik analizleri ile yapıldı. Elde edilen polimerlerinin ısısal stabiliteleri TG/DTG-DTA, DSC ve DMA analizleri ile belirlendi. Ayrıca her bir polimerin ısısal katı hal bozunma kinetikleri farklı sınıflara ait birçok yöntem kullanılarak hesaplandı ve polimerlerin bozunma basamaklarına ait matematiksel fonksiyonlar bulundu. Çalı?manın diğer a?amasında oksidatif polimerizasyon yöntemi ile hazırlanan farklı oranlardaki polimeriler twin-screw microextruder?de poliolefin temelli malzemeler (AYPET, YYPE ve PP) ile blendleri hazırlandı. Hazırlanan blendlerin spektral, morfolojik, fizikomekanik ve ESD karakterizasyonları yapıldı. Çalı?manın son a?amasında sentezlenen her bir polimerlerin poliolefin temelli malzemelerde meydana getirdiği ısısal deği?imler ve bu deği?imlerle ilgili kinetik modellemeler belirlendi.
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    Enzymatic polymerization of hydroxy-functionalized carbazole monomer
    (Elsevier, 2010) Bilici, Ali; Kaya, İsmet; Yıldırım, Mehmet; Doğan, Fatih
    Up to date, enzymatic polymerization of phenolic compounds bearing different moieties such as ferrocene, sugar, furamide, and male-imide have been reported. In this study, horseradish peroxidase (HRP)-catalyzed polymerization of another hydroxy substituted aromatic compound, 2-hydroxycarbazole (HC), was firstly presented. The structure of the polymer (PHC) was verified by using nuclear magnetic resonance and infrared techniques. Further characterization was carried out by means of TG, DSC, CV (cyclic voltammetry), SEM (scanning electron microscopy), fluorescence analyses, and solid state conductivity measurements. Average molecular weight of the polymer was determined by gel permeation chromatography and was around two thousands. The optical and electrochemical band gaps of PHC were dramatically lower than those of HC. The photochemical behaviors of HC and PHC were investigated by recording the fluorescence spectra in two different solvents. Solid state conductivity measurement showed that the electrical conductivity value of hydroxyl-functionalized carbazole polymer is relatively higher than those of the previously reported phenol polymers in the literature. Moreover, the conductivity of PHC increased by doping with iodine vapour. (C) 2010 Elsevier B.V. All rights reserved.
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    Facile and regioselective synthesis of poly(5-hydroxyquinoline)
    (Elsevier, 2011) Bilici, Ali; Doğan, Fatih; Yıldırım, Mehmet; Kaya, İsmet
    The oxidative polymerization (OP) of unprotected 5-hydroxyquinoline (HQ) in an aqueous alkaline medium without an added external template, surfactants or functional dopants, leads to the formation of the C-3 and C-6 linked organic solvent-soluble, quinoline homopolymer (PHQ). The polymer had an average molecular weight of M-n = 37,400 with a polydispersity index of 1.65. The fluorescence spectrum of PHQ exhibited an emission peak at approximately 500 nm in dimethyl sulfoxide (DMSO), which was nearly 118 nm red-shifted compared to the monomeric compound. In solution, PHQ showed fluorescence solvatochromism: it emitted blue light in tetrahydrofuran (THF) and green light in dimethylformamide (DMF) solutions with a relatively narrow full width of half maximum (FWHM). X-ray diffraction (XRD), scanning electron microscope (SEM) and atomic force microscope (AFM) analyses indicated that the resulting polymer was semicrystalline. Iodine doped-PHQ exhibited values of conductivity nearly 10(5) times higher compared to the undoped PHQ Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.
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    Facile synthesis of self-stabilized polyphenol nanoparticles
    (Elsevier Science Sa, 2013) Bilici, Ali; Doğan, Fatih; Yıldırım, Mehmet; Kaya, İsmet
    We describe here the facile synthesis (in two-steps) of green light emitting phenol polymer with an azomethine side group. For this purpose, hydroxy functionalized-Schiff base monomer, HPMBT, was obtained by condensation of 2,3,4-trihydroxybenzaldehyde with 2-aminophenol. Subsequent oxidation of the monomer in alkaline medium by NaOCl yielded to corresponding phenol polymer (PHPMBT) with molecular weight ca. 34,500 Da. The characterizations were performed by NMR, FT-IR, UV-vis, gel permeation chromatography (GPC), thermogravimetry (TG), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), cyclic voltammetry (CV), photoluminescence (PL), dynamic light scattering (DLS) and scanning electron microscope (SEM) analysis. PL analysis indicated that HPMBT was non-fluorescent whereas PHPMBT was a green light emitter. In addition, the redox behaviors of the polymer were explored by cyclic voltammetry (CV), assigned it's electroactive nature. The formation of nano-sized polyphenol particles was revealed by the SEM and DLS analyses. A possible mechanism for the formation and self-stabilization of the polyphenol nanoparticles was also suggested. (C) 2013 Elsevier B.V. All rights reserved.
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