Person: TEMEL, BİNNUR
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Publication Metadata only Single-Chain Folding Nanoparticles as Carbon Nanotube Catchers(2018-12-15T00:00:00Z) BİLGİ, Mesut; Balta, Demet Karaca; Temel, Binnur Aydogan; Temel, Gokhan; TEMEL, BİNNURThis contribution describes a simple method for preparing polymeric nanoparticles using photodimerization of anthracene moieties on the side chain of terpolymers in dilute regime and transformation of obtained polymeric nanoparticles into pyrene functional nanoparticles via Menschutkin quaternization procedure. Subsequently, pyrene possessing polymeric nanoparticles are attached onto multiwalled carbon nanotube (MWCNT) surfaces by pi-pi stacking strategy. Gel permeation chromatography, thermal gravimetric analysis, ultraviolet-visible, and fluorescence spectroscopies are used to analyze modified nanoparticles and their precursors. Electron microscopy and dispersion studies show that pyrene-modified polymeric nanoparticles are able to interconnect various CNTs. (c) 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2709-2714Publication Metadata only Thioxanthone-Fluorenes as Visible Light Photoinitiators for Free Radical Polymerization(2010-05-25T00:00:00Z) Yilmaz, Gorkem; Aydogan, Binnur; Temel, Gokhan; ARSU, Nergis; MOSZNER, Norbert; Yağcı, Yusuf; TEMEL, BİNNURTwo thioxanthone derivatives with fluorene additional chromophoric groups, namely thioxanthone-fluorenecarboxylie acid (TX-FLCOOH) and thioxanthone fluorene sodium carboxylate (TX-FLCOONa), as visible light absorbing oil- and water-soluble photoinitiators, respectively, were synthesized and characterized. Their ability to initiate photopolymerization of methyl methacrylate (M MA), 2-(2-phosphonoethoxymethyl)acrylic acid ethyl ester (EAEPA), and a multifunctional monomer, trimethylolpropane triacrylate (TMPTA), were examined. The initiation efficiency of TX-FLCOOH was compared with the parent thioxantone (TX) both in the presence and in the absence of a co-initiator, and TX-FLCOOH was found to be more effective in :ill cases. Photopolymerization and laser flash photolysis studies revealed that depending on the concentration initiation by TX-FLCOOH occurs by intra and intermolecular H-abstraction of the triplet (3)(TX-FLCOOH)*. No polymerization was observed when TX-FLCOONa was used as photoinitiator in the absence of a co-initiator. However, TX-FLCOONa acts as an efficient initiator in the visible range in the presence of H donors in water.Publication Metadata only Single-chainpolymer nanoparticles via click crosslinking and effect of photoinduced radical combination on crosslink points(2020-07-01T00:00:00Z) Keklik, Merve; Akar, Irem; Temel, BİNNUR; Balta, Demet Karaca; Temel, Gokhan; TEMEL, BİNNURFolding of azide functionalized polymer chains was obtained via the copper-catalyzed azide alkyne cycloaddition (CuAAC) methodology using a light-responsive crosslinker as the -click- component. Subsequently, crosslinked junction points were combined with a photoinduced radical combination strategy to achieve more compact nanoparticles. The resultant folding particles possess smaller particle sizes and higher glass transition temperature values compared to their linear analogues. Fourier transform IR spectroscopy, SEC, DSC, dynamic light scattering,H-1 NMR and TEM techniques were used for characterization. (c) 2020 Society of Chemical IndustryPublication Metadata only Preparation of single chain nanoparticles via photoinduced radical coupling process(2019-04-01) Dashan, Irem; Balta, Demet Karaca; Temel, BİNNUR; Temel, Gokhan; TEMEL, BİNNURThis contribution introduces a straightforward method for preparing well-defined polymeric nanoparticles using radical coupling process of ketyl moieties resulted from triplet excitation of pendant benzophenone groups. In the first step, poly(styrene-co-chloromethylstyrene) is synthesized by thermally initiated controlled radical co-polymerization technique and subsequently, pendant chloride groups undergo post-modification with 4-hydroxybenzophenone. Achieved well-defined side-chain benzophenone containing copolymers generate ketyl radicals in the presence of excess hydrogen donor molecule upon UV-light irradiation and intramolecularly crosslinked nanoparticles are formed by radical coupling process in dilute regime. Resulting single chain nanoparticles and intermediates are characterized by H-1 NMR, gel permeation chromatography, differential scanning calorimetry, UV-Vis spectrometry and electron microscopy techniques.Publication Metadata only Versatile light-responsive organogels: Evaluation of their dye releasing and photoinitiation behaviors(2019-06-15) Dashan, Irem; Elverici, Melisa; Balta, Demet Karaca; Temel, BİNNUR; Temel, Gokhan; TEMEL, BİNNURLight-responsive crosslinked structures were prepared by a straightforward quaternization strategy using chloride functional polystyrene copolymers and commercially available Michler-s ketone with varying feed ratios. Resulting organogels demonstrated excellent solvent absorption and their swelling characteristics were altered by UV-light irradiation. According to scanning electron microscope images, UV-illuminated samples showed an obvious photodecomposition, which enhanced their solvent uptake capacity with increase of UV exposure. Additionally, release behavior of eosin Y as a model compound was determined by UV-vis and fluorescence spectrometers. Achieved photoactive gels were also employed as the reusable heterogeneous initiators for photoinduced free-radical polymerization of methyl methacrylate. (c) 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1275-1282Publication Metadata only Single-chain polymeric nanoparticles using 4-armed star copolymers(2020-06-26T00:00:00Z) Genc, Fatih; Temel, Gokhan; Temel, BİNNUR; TEMEL, BİNNURPublication Metadata only Preparation of Single Chain Nanoparticles via Photoinduced Double Collapse Process(2019-05-01T00:00:00Z) Dashan, Irem; Balta, Demet Karaca; Temel, Binnur Aydogan; Temel, Gokhan; TEMEL, BİNNURA straightforward method is described to achieve polymeric nanoparticles by double folding of single linear chains. The side chain functional polystyrene with controlled molecular weight is converted to pendant azide and benzophenone motifs via postmodification reactions. Resulting functionalized chains undergo intramolecular crosslinking upon ultraviolet (UV) illumination using simultaneous and subsequent pathways at a dilute concentration. Particle size of nanoparticles can be tuned by changing the degree of crosslinking using a second folding process. Obtained single and double collapsed chains indicate higher glass transition temperatures and lower hydrodynamic radii compared to their intermediates. To our knowledge, the combination of photoinduced azide crosslinking and radical coupling processes is the first attempt to prepare double folding single polymer chains.Publication Metadata only Rapid synthesis of fluorescent single-chain nanoparticles via photoinduced step-growth polymerization of pendant carbazole units(2020-02-15T00:00:00Z) KILIÇ, Deniz; Pamukcu, Ceren; Balta, Demet Karaca; Temel, BİNNUR; Temel, Gokhan; TEMEL, BİNNURAn easy and rapid strategy is developed to synthesize light responsive single-chain nanoparticles via photo induced radical coupling of carbazole moieties in the side chain of polymer. Firstly, nitroxide-mediated radical polymerization is carried out for the synthesis of chloride functional styrenic copolymer. Pendant chloride groups of the polystyrene copolymer are converted to carbazole units by one-step modification. Constructed functional polymer undergoes photochemically intramolecular crosslinking using carbazole step-growth polymerization. Size of the nanoparticles can be manipulated by changing the degree of polymerization which is dependent to the dose of UV exposure. Achieved single-chain nanoparticles exhibit higher glass transition temperatures and lower hydrodynamic radii compared to their linear analogue. Polymeric nanoparticles are successfully employed for the cyclohexane oxide polymerization as cationic photoinitiators in the presence of an iodonium salt.