Browsing by Author "Pekcan, Mehmet Önder"
Now showing items 1-20 of 54
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Cation effect on gel-sol transition of kappa carrageenan
Pekcan, Mehmet Önder; Tarı İlgin, Özlem (Springer, 2008-04)The steady state fluorescence (SSF) technique was employed to study gel - sol transitions of kappa carrageenan in NaCl, KCl and CaCl2 solutions. Pyranine was used as a fluorescence probe for monitoring these transitions. ... -
Cation effects on phase transition of kappa-iota-carrageenan hybrids: a photon transmission study
Pekcan, Mehmet Önder; Kara, Selim; Arda, Ertan (Taylor & Francis Group, 2007)Phase transitions of kappa-iota-carrageenan hybrid in various types of salts were studied using photon transmission technique: NaCl, KCI, MgCl2, CaCl2 and KCl+CaCl2 were chosen as the salt solutions for the carrageenan ... -
Ceramic encapsulated latex composites
Uğur, Şaziye; Pehlivan, Esat; Tepehan, Fatma Zehra; Pekcan, Mehmet Önder (Elsevier Inc, 2006-04-15)This work reports the encapsulation of latex particles in Al(2)O(3)-polystyrene (PS) composite films. These films were prepared from PS particles in Al(2)O(3) dispersion at room temperature in various latex contents. ... -
Comparision of critical parameters of polymerization and gelation processes: A fast transient fluorescence study
Kaya Aktaş, Demet; Pekcan, Mehmet Önder (World Scientific Publ Co Pte Ltd, 2005-03-10)The fast transient fluorescence technique was used to study free-radical polymerization and crosslinking copolymerization of styrene. Ethylene glycol dimethacrylate and Pyrene were used as crosslinking agent and fluorescence ... -
Critical behavior of thermal phase transitions of iota-carrageenan in CaCl2 solution
Özbek, Haluk; Pekcan, Mehmet Önder (Elsevier B.V., 2006-07-15)In situ photon transmission method was applied to study thermal phase transitions of ?-carrageenan in CaCl2 solution. Coil-to-helix (c-h) and helix-to-dimer (h-d) transitions were detected upon cooling. An extra dimer-to-dimer ... -
Determination of pre-gelation and post-gelation activation energies during free radical crosslinking copolymerization
Kaya Aktaş, Demet; Pekcan, Mehmet Önder (Taylor & Francis Ltd, 2005)Steady-state fluorescence (SSF) and dilatoraetric techniques were used to study the free-radical crosslinking copolymerization (FCC) of styrene (S) and divinylbenzene (DVB) in bulk. The gel points (t g) were recorded by ... -
Dissolution of Al2O3-polystyrene latex composites: A fluorescence study
Uǧur, Şaziye; Tepehan, Fatma Zehra; Pekcan, Mehmet Önder (Taylor & Francis Ltd, 2005)This work reports the use of the steady state fluorescence (SSF) technique to study dissolution of a composite film formed from a mixture of Al 2O3 and polystyrene (PS) latex particles. The composite films were cast from ... -
Drying of PAAm hydrogels at various temperatures: A fluorescence study
Aktaş, Demet Kaya; Evingür, Gülşen Akın; Pekcan, Mehmet Önder (Taylor & Francis Group, 2007-05)The steady-state fluorescence (SSF) technique was employed for studying the drying of polyacrylamide (PAAm) hydrogels. Disc-shaped hydrogels were prepared by free-radical crosslinking copolymerization of acrylamide (AAm) ... -
Effect of annealing rate on film formation from poly(vinyl acetate) latex particles
Arda, Ertan; Kara, Selim; Pekcan, Mehmet Önder (Taylor & Francis Ltd, 2008)The photon transmission technique was used to monitor the time and temperature evolution of film formation from poly(vinyl acetate) (PVAc) latex particles. The latex films were prepared below the glass transition temperature ... -
The effect of clay particles on film formation from polystyrene latex
Uğur, Şaziye; Alemdar, Ayşe; Pekcan, Mehmet Önder (Wiley, 2006-06)Film formation from surfactant-free polystyrene (PS) latex was performed in the presence of 5% Na-montmorillonite (NaMMT). The composite films were prepared from pyrene (P)-labeled PS particles at room temperature and ... -
Effects of annealing on morphology of polymer/polymer (PS/PMMA) blend; a fluorescence study
Uğur, Şaziye; Pekcan, Mehmet Önder (John Wiley& Sons Inc, 2006-05-05)Steady state fluorescence (SSF) technique conjunction with optical microscopy were used to study the morphology of polystyrene (PS)/poly(methyl methacrylate) (PMMA) blend upon annealing above glass transition in elevated ... -
Film formation from nano-sized polystrene latex covered with various TiO2 layers
Uğur, Şaziye; Sunay, Selin; Elaissari, Abdelhamid; Tepehan, Fatma Zehra; Pekcan, Mehmet Önder (Wiley, 2006-12)Steady-state fluorescence technique was used for studying film formation from TiO2 covered nano-sized polystyrene latex particles. The composite films were prepared from pyrene (P)-labeled PS particles by covering them ... -
Film formation from nano-sized polystyrene latex particles
Uğur, Şaziye; Elaissari, Abdelhamid; Pekcan, Mehmet Önder (John Wiley & Sons Ltd, 2005-05)This work reports on the steady state fluorescence (SSF) technique for studying film formation from surfactant-free, nano-sized polystyrene (PS) latex particles prepared via emulsion polymerization. The latex films were ... -
Film formation from PS latex doped PNIPAM hydrogels at various heating and cooling rates
Uğur, Şaziye; Yargı, Önder; Pekcan, Mehmet Önder (VSP BV, Brill Academic Publishers, 2008-05-01)Film formation from polystrene (PS) latex doped poly(N-isopropylacrylamide) (PNIPAM) hydrogels was studied by using photon transmission technique. The transmitted light intensity, It, was monitored during film formation ... -
Film formation from pure and mixed latices; transient fluorescence study
Uğur, Şaziye; Pekcan, Mehmet Önder (Academic Press Inc Elsevier Science, 2005-11-15)A fast transient fluorescence technique was used to study latex film formation induced by organic solvent vapor. Mixtures of pyrene (P)- and naphthalene (N)-labeled and/or pure naphthalene-labeled latex films were prepared ... -
Film formation from TiO2-polystyrene latex composite: a fluorescence study
Uğur, Şaziye; Sunay Yapışkan, Münüre Selin; Tepehan, Fatma Zehra; Pekcan, Mehmet Önder (Taylor & Francis Group, 2007-03-01)This work reports the use of the steady state fluorescence (SSF) technique for studying film formation from TiO2 covered polystyrene (PS) latex particles. The composite films were prepared from pyrene (P)-labeled PS particles ... -
Film formation stages for poly(vinyl acetate) latex particles: a photon transmission study
Kara, Selim; Pekcan, Mehmet Önder; Saraç, Ayfer; Arda, Ertan (Springer-Verlag, 2006-07)Photon transmission technique was used to monitor the evolution of transparency during film formation from poly(vinyl acetate) (PVAc) latex particles. The latex films were prepared below the glass transition temperature ... -
Films formed from polystyrene latex/clay composites: A fluorescence study
Uğur, Şaziye; Alemdar, Ayşe; Pekcan, Mehmet Önder (Springer New York, 2005-07)This study reports a steady-state fluorescence (SSF) technique for studying film formation from surractant-free polystyrene (PS) latex and Na-montmorillonite (SNaM) composites. The composite films were prepared from pyrene ... -
Fluorescence study on Al2O3-polystyrene latex composite film formation
Uğur, Şaziye; Salman, Oğuz Umut; Tepehan, Galip Gültekin; Tepehan, Fatma Zehra; Pekcan, Mehmet Önder (John Wiley & Sons Inc, 2005-06)This work reports a steady state fluorescence (SSF) technique for studying film formation from mixture of Al2O3 and polystyrene (PS) latex particles. The composite films were prepared from dispersion of pyrene (P)labeled ... -
In situ fluorescence study of swelling, sorption and desorption processes in and out of PAAm gels
Evingür, Gülşen Akın; Karslı, Kadir; Pekcan, Mehmet Önder (Wiley-V C H Verlag GMBH, 2008-05)Small molecule sorption and desorption in and out of polyacrylamide (PAAm) gels were studied at various temperatures. Pyranine (P(y)) dissolved in water used as a probe. Fluorescence emission intensity, I(p) from P(y) was ...
