Browsing by Author "Sunay, M. Selin"

Now showing 1 - 7 of 7

Citation Count: 3
The effect of film thickness and TiO2 content on film formation from PS/TiO2 nanocomposites prepared by dip-coating method
(Hindawi Publishing Corporation, 2012) Sunay, M. Selin; Pekcan, Önder; Ugur, Saziye
Steady-state fluorescence (SSF) technique in conjunction with UV-visible (UVV) technique and atomic force microscope (AFM) was used for studying film formation from TiO2 covered nanosized polystyrene (PS) latex particles (320 nm). The effects of film thickness and TiO2 content on the film formation and structure properties of PS/TiO2 composites were studied. For this purpose two different sets of PS films with thicknesses of 5 and 20 mu m were prepared from pyrene-(P-) labeled PS particles and covered with various layers of TiO2 using dip-coating method. These films were then annealed at elevated temperatures above glass transition temperature (T-g) of PS in the range of 100-280 degrees C. Fluorescence emission intensity I-p from P and transmitted light intensity I-tr were measured after each annealing step to monitor the stages of film formation. The results showed that film formation from PS latexes occurs on the top surface of PS/TiO2 composites and thus developed independent of TiO2 content for both film sets. But the surface morphology of the films was found to vary with both TiO2 content and film thickness. After removal of PS thin films provide a quite ordered porous structure while thick films showed nonporous structure.
Citation Count: 0
Fluorescence study of effect of particle size in PS latex/Al2O3 nanocomposite films
(MANEY PUBLISHING, 2015) Uğur, Şaziye; Sunay, M. Selin; Pekcan, Önder
Steady state fluorescence and BioUV-Visible techniques were used to study film formation of polystyrene (PS) latex and Al2O3 composites depending on PS particles size and Al2O3 content. Two film series (SmPS/Al2O3 and LgPS/Al2O3) were prepared covering PS sphere (SmPS: 203 nm
Citation Count: 0
Fluorescence Study of Film Formation from PS Latex-TiO2 Composites: Effects of TiO2 Content Film Thickness and Particle Size
(Amer Scientific Publishers, 2015) Ugur, Saziye; Sunay, M. Selin; Pekcan, Önder
Steady-state fluorescence (SSF) technique in conjunction with UV-visible (UVV) technique atomic force microscope (AFM) and scanning electron microscope (SEM) is used for studying film formation from TiO2 covered polystyrene (PS) latex particles. The effects of TiO2 content film thickness and PS particle size on film formation and structure properties of PS/TiO2 composites are studied. For this purpose in the first part two different sets of PS films with thicknesses of 5 and 20 mu m were prepared from pyrene-(P-) labeled PS particles (320 nm) and covered with various layers of TiO2 with the use of dip-coating method. These films were then annealed at elevated temperatures above glass transition temperature (T-g) of PS in the range of 100-280 degrees C. Fluorescence emission intensity I-p from P and transmitted light intensity I-tr were measured after each annealing step to monitor the stages of film formation. The results show that film formation from PS latexes occurs on the top surface of PS/TiO2 composites and thus develop independent from TiO2 content for both film sets. However the surface morphology of the films was found to vary with both TiO2 content and film thickness. After removal of PS thin films provide a quite ordered porous structure while thick films show nonporous structure. In the second Part two film series were prepared from PS particles with diameters of 203 nm (SmPS) and 382 nm (LgPS) covered with different layers of TiO2 and annealed at elevated temperatures. Results reveal that SmPS/TiO2 films undergo complete film formation independent of the TiO2 content. However no film formation occurs above a certain TiO2 content in LgPS/TiO2 films. SEM images demonstrate that SmPS/TiO2 films have highly well-ordered microporous structures with increasing TiO2 content after extraction of PS polymer whereas LgPS/TiO2 composites show no porous structure for high TiO2 content. Our experiments also show that porous TiO2 films with different sizes could successfully be prepared with this technique.
Citation Count: 1
Fluorescence study of film formation from PS/Al2O3 nanocomposites
(Elsevier Science, 2014) Pekcan, Önder; Uğur, Şaziye; Sunay, M. Selin
Steady state fluorescence (SSF) and UV-vis (UVV) techniques were used to study the film formation behavior of pyrene (P) labeled polystyrene (PS) latex and Al2O3 (PS/Al2O3) composites depending on PS particles size and Al2O3 content. The close-packed arrays of PS spheres (SmPS: 203 nm ; LgPS: 382 nm) templates on clean glass substrates were covered with various layers of Al2O3 by dip-coating method. Two different film series (SmPS/Al2O3 and LgPS/Al2O3) were prepared in various Al2O3 layer content. The film formation behavior of these composites were studied by annealing them at a temperature range of 100-250 degrees C and monitoring the scattered light intensity (I-sc) fluorescence intensity (I-p) from P and transmitted light intensity (I-tr) through the films after each annealing step. Optical results indicate that classical latex film formation was occurred for all Al2O3 content films and film formation process was unaffected by the Al2O3 content for both film series. Extraction of PS template produced highly ordered porous structures for high Al2O3 content in both film series. SEM images showed that the pore size and porosity could be easily tailored by varying the PS particle size and the Al2O3 content. (C) 2014 Elsevier B.V. All rights reserved.
Citation Count: 5
Particle Size Effect on the Film-Forming Process of PS/PBA Composite Latexes
(John Wiley & Sons Inc, 2010) Uğur, Şaziye; Sunay, M. Selin; Elaissari, Abdelhamid; Pekcan, Önder
In this work the effect of hard particle size and blend ratio on the film formation behavior of hard polystyrene (PS) and soft poly(n-butyl acrylate) (PBA) latex blends was studied by means of steady-state fluorescence and UV-visible techniques in conjunction with atomic force microscopy. Three different sets of latexes were synthesized: PBA latex (diameter 97 nm) pyrene (P)-labeled large PS (LgPS
Citation Count: 4
Spectroscopic study of film formation from polystyrene latex/TiO2 nanocomposites prepared by dip-coating method
(Wiley-Blackwell, 2014) Sunay, M. Selin; Pekcan, Önder; Rahman, Md. Mahbubor; Elaissari, Abdelhamid; Ugur, Saziye
In this study we investigated the influence of TiO2 content and thickness of polystyrene (PS) template on film-formation behavior of PS/TiO2 composites using fluorescence and ultraviolet-visible techniques in conjunction with scanning electron microscopy. Films were prepared by coating PS templates with various layers of TiO2 using dip-coating method. The results showed that PS latexes present complete film formation on top surface of composites. After extraction of PS a well-defined interconnected porosity were obtained for thin films when TiO2 content was increased whereas thick samples did not present any interconnected porous structures above a certain TiO2 layer. POLYM. ENG. SCI. 54:288-302 2014. (c) 2013 Society of Plastics Engineers
Citation Count: 2
Study of Film Formation From PS Latex/TiO2 Nanocomposites
(Wiley-Blackwell, 2014) Uğur, Saziye; Sunay, M. Selin; Pekcan, Önder
In this work we investigated the film formation from polystyrene (PS) latex/TiO2 nanocomposites using the steady state fluorescence (SSF) and UV-vis (UVV) techniques depending on PS particle size and TiO2 content. The structural properties of films were characterized by scanning electron microscope (SEM). The films were prepared from pyrene (P)-labeled PS particles (SmPS: 203 nm