Yazar "Asilturk, Meltem" seçeneğine göre listele
Listeleniyor 1 - 20 / 24
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Antibacterial glass films prepared on metal surfaces by sol-gel method(Springer, 2010) Kiraz, Nadir; Kesmez, Omer; Burunkaya, Esin; Budama, Leyla; Acar, Burcin; Asilturk, Meltem; Camurlu, H. ErdemThis paper describes the preparation and characterization of glass films consisting of SiO2, Li2O, Na2O, K2O or MgO in varying compositions on stainless steel and aluminum substrates by sol-gel method. Silver phosphate or silver incorporated zeolite was also introduced into the sols for obtaining antibacterial effect. The SiO2/Li2O/Na2O system having the composition of 85:5:10 wt% was found as the optimum for obtaining a stable sol and film formation. The films were investigated by scanning electron microscopy (SEM) and electron dispersive analysis by X-ray (EDX), Fourier transformed infrared (FTIR) spectroscopy, thermo-gravimetric analysis (TGA) and differential thermal analysis (DTA). Homogenous films having 300 +/- A 20 nm thicknesses were formed by spin coating and then by curing at 500 A degrees C for 1 h. Obtained films had high adherence to the metal substrates and they were also durable in acidic, basic or NaCl environments. They also presented a powerful antibacterial effect against E. coli.Öğe Cellulose acetate encapsulated upconversion nanoparticles - A novel theranostic platform(Elsevier, 2021) Topel, Seda Demirel; Balcioglu, Sevgi; Ates, Burhan; Asilturk, Meltem; Topel, Onder; Ericson, Marica B.Luminescent upconversion nanoparticles (UCNPs) are of great interest in a wide range of nanotechnological applications, particularly in the biomedical area like imaging and therapy but their biocompatibility and stability pose major challenges hampering progression towards further pharmaceutical applications. Herein, we present a biocompatible theranostic platform enabling simultaneous diagnosis and drug delivery consisting of UCNPs encapsulated with cellulose acetate (CA), a biocompatible polymer. Luminescence properties of UCNPs in the developed theranostic platform remain stable even after encapsulation. The size of the CA capsules, ranging from micro- to nano-sized particles, can easily be tuned by adjusting the stirring rate during encapsulation. Doxorubicin, a well-known chemotherapeutic drug, onto the CA nanocapsules containing UCNPs (UCNP-CA nanocapsules) was loaded with up to -63 % efficiency and acid-induced release (similar to 47 %) obtained at pH 3.6 and 5.5. It was found that encapsulation decreased toxicity of UCNPs as confirmed in a cellular assay (L-929 and MCF-7 cell lines). Taken together, the developed UCNP-CA nanocapsules serve as a highly interesting novel theranostic platform, combining the biocompatible optical properties of UCNP, with reduced cell toxicity and drug encapsulating properties of CA. The proposed system could be subject for further refinement and exploration.Öğe Effect of acid, water and alcohol ratios on sol-gel preparation of antireflective amorphous SiO2 coatings(Elsevier Science Bv, 2011) Kesmez, Omer; Burunkaya, Esin; Kiraz, Nadir; Camurlu, H. Erdem; Asilturk, Meltem; Arpac, ErtugrulVarying amounts of nitric acid catalyst, water and ethyl alcohol were used in the preparation of SiO2 sols by hydrolysis and condensation reactions of tetraethyl orthosilicate in a one step acid catalysis process. Hydrolysis of TEOS was followed by FT-IR analyses. Size of SiO2 particles was seen to vary in 8-41 nm range with respect to changing HNO3 and water amounts in the sols. Gelation occurred in some systems. Surfaces of films were examined by FESEM and AFM, after coating on glass substrates by dip coating. Thicknesses of the films were measured to be in the range of 80-120 nm. 5.6 +/- 0.2% point increase in light transmittance was obtained when HNO3/TEOS (mol/mol) ratio of 4.74 x 10(-4) and H2O/TEOS (mol/mol) ratio of 9.08 were utilized. Sols were found to be stable for months and coatings prepared after 45 days still provided 5.2 +/- 0.2% point increase in light transmittance. (C) 2011 Elsevier B.V. All rights reserved.Öğe Effect of amine catalysts on preparation of nanometric SiO2 particles and antireflective films via sol-gel method(Springer, 2010) Kesmez, Omer; Kiraz, Nadir; Burunkaya, Esin; Camurlu, H. Erdem; Asilturk, Meltem; Arpac, ErtugrulSiO2 sols were prepared by hydrolysis and condensation reactions of tetraethyl orthosilicate through a one step acid or a two step acid + base catalysis process, in the presence of nitric acid and four different base catalyzers, namely trimethylamine, triethylamine, tripropylamine and tributylamine. Hydrolysis of TEOS was followed by FT-IR analyses. Particle size distributions of the sols were evaluated after predetermined durations in 1-22 days. Particle growth was seen to be faster in amine catalyzed systems than in one step acid catalyzed system. The highest rate of growth was in triethylamine catalyzed system. Glass substrates were dip coated with the prepared SiO2 sols. Effect of sol aging duration on film thickness and on light transmittance properties of the films was investigated with respect to type of base catalyst. Thicknesses of the films which were measured to be in the range of 100-400 nm, were seen to increase with aging duration of the sols. Triethylamine catalyzed system presented the highest film thickness. Films obtained from one step acid catalyzed system presented an increase of 4.8%; whereas acid + base catalyzed films provided an increase in the light transmittance of 5.7% in the first 4 days of aging. Surfaces of films were examined by FESEM and AFM. The antireflective character of the films was verified by diffuse reflectance analyses.Öğe Effect of Fe3+ ion doping to TiO2 on the photocatalytic degradation of Malachite Green dye under UV and vis-irradiation(Elsevier Science Sa, 2009) Asilturk, Meltem; Sayilkan, Funda; Arpac, ErtugrulFe3+ ion-doped TiO2 particles were synthesized by the hydrothermal process at 225 degrees C. Titanium isopropoxide (Ti(OPri)(4)) was used as precursor material. Both undoped and doped TiO2 particles were used to coat glass surface. The coated surface was examined with respect to their photocatalytic performance for degradation of Malachite Green (MG) dye in aqueous solution under UV and vis-light irradiation. The particles and the films were characterized by XRD, SEM and UV/vis/NIR techniques. The results showed that crystallite size of the hydrothermally synthesized TiO2 particles are in nanoscale. Anatase was only the crystalline phase. Doping of Fe3+ ion improved the photodegradation performance of TiO2 coated surfaces. Degradation performance of Fe3+ doped TiO2. coated surfaces determined under UV- and vis-irradiation conditions was higher than the undoped TiO2 coated surface. It was concluded that the photodegradation of 2.5 mg L-1 MG under UV-light irradiation with the catalysis of Fe3+-doped TiO2 follows the pseudo-first-order reaction kinetics with the rate constant of 0.0202 min(-1). (C) 2008 Elsevier B.V. All rights reservedÖğe Effects of coating with different ceromers on the impact strength, transverse strength and elastic modulus of polymethyl methacrylate(Japanese Soc Dental Materials Devices, 2015) Gul, Esma Basak; Atala, Mustafa Hayati; Eser, Bekir; Polat, Nilufer Tulin; Asilturk, Meltem; Gultek, AhmetThe aim of this study was to evaluate the mechanical properties of polymethyl methacrylate (PMMA) after coating with different ceromers. For transverse strength and modulus of elasticity tests, specimens of 65x10x2.5 mm dimensions were prepared (5 groups, n=10). For impact strength test, specimens of 60x7.5x4 mm dimensions were prepared (5 groups, n=10). Test group specimens were coated with one of four different types of ceromers, and specimens in the control group were not coated. After specimens were tested for transverse and impact strengths, the data were analyzed with Kruskal-Wallis and Conover post hoc tests (p<0.05). GLYMOTEOS-TiO2 and A174-TEOS significantly increased the transverse strength of PMMA. All ceromers caused a statistically significant increase in the elastic modulus of PMMA. While GLYMO-TEOS-ZrO2 significantly decreased the impact strength, the other ceromers did not cause any statistically significant difference in impact strength. Coating with ceromers substantially improved the mechanical properties of PMMA.Öğe Enhancement of enzyme activity by laser-induced energy propulsion of upconverting nanoparticles under near-infrared light: A comprehensive methodology for in vitro and in vivo applications(Elsevier, 2024) Ates, Burhan; Ulu, Ahmet; Asilturk, Meltem; Noma, Samir Abbas Ali; Topel, Seda Demirel; Dik, Gamze; Ozhan, OnuralIf the appropriate immobilization method and carrier support are not selected, partial decreases in the activity of enzymes may occur after immobilization. Herein, to overcome this challenge, an excitation mechanism that enables energy transfer was proposed. Modified upconverting nanoparticles (UCNPs) were constructed and the important role of near-infrared (NIR) excitation in enhancing the catalytic activity of the enzyme was demonstrated. For this purpose, UCNPs were first synthesized via the hydrothermal method, functionalized with isocyanate groups, and then, PEG-L-ASNase was immobilized via covalent binding. UCNPs with and without PEG-LASNase were extensively characterized by different methods. These supports had immobilization yield and activity efficiency of >96 % and 78 %, respectively. Moreover, immobilized enzymes exhibited improved pH, thermal, and storage stability. In addition, they retained >65 % of their initial activity even after 20 catalytic cycles. Biochemical and histological findings did not indicate a trend of toxicity in rats due to UCNPs. Most importantly, PEG-L-ASNase activity was triggered approximately 5- and 2-fold under in vitro and in vivo conditions, respectively. Overall, it is anticipated that this pioneering work will shed new light on the realistic and promising usage of NIR-excited UCNPs for the immobilization of enzymes in expensive and extensive applications.Öğe Evaluation on reducing toxicity of fluoxastrobin with doped TiO2 nanoparticles(Tubitak Scientific & Technological Research Council Turkey, 2021) Gungordu, Abbas; Ozmen, Nesrin; Erdemoglu, Sema; Turhan, Duygu Ozhan; Asilturk, Meltem; Akgeyik, Emrah; Ozmen, MuratIn this study, toxic effects caused by the degradation of fluoxastrobin, which is a commonly used fungicide where newly synthesized manganese or sulfur-doped TiO2 nanoparticles exist were evaluated. The characterization study of nanoparticles was performed by scanning an electron microscopy (SEM), X-ray diffractometry, Brunau-Emmet-Teller analysis, X-ray fluorescence spectroscopy, and UV-Vis (ultraviolet-visible) reflectance spectra. Subsequently, the photocatalytic performance of nanoparticles, their toxicity, and the photocatalytic degradation products of fluoxastrobin with the same nanoparticles were tested during the two development stages of Xenopus laevis. The LC(50)s of fluoxastrobin were determined on test organisms, and a 5 mg L-1 fluoxastrobin was selected to evaluate the photocatalytic degradation capacity due to toxicity studies. The sublethal effects of the nanoparticles and the degradation product of fluoxastrobin were assessed with embryonic malformations and biochemical marker responses. Sulfur-doped TiO2 was found to be more effective compared to manganese-doped TiO2 for the degradation of fluoxastrobin, photocatalytically. On the other hand, even if the tested nanoparticles were not lethal, they caused effects such as growth retardation and changes in biochemical responses on organisms.Öğe Hydrophilic hybrid SiO2:polyethylene glycol-3-isocyanato-propyltrietoxysilane nanocomposite films(Elsevier Science Sa, 2012) Burunkaya, Esin; Kesmez, Omer; Kiraz, Nadir; Camurlu, H. Erdem; Asilturk, Meltem; Arpac, ErtugrulSiO2:polyethylene glycol (PEG)-3-isocyanato-propyltrietoxysilane (IPTES) hydrophilic films were prepared from PEG having various average molecular weights, namely 200, 400 and 600; SiO2 nanoparticles, and tetraethyl orthosilicate (TEOS) through sol-gel method. SiO2 nanoparticles were utilized in various amounts to enhance the mechanical properties and hydrophilic character of the films. Films were characterized by Fourier transformed infrared spectroscopy, field emission scanning electron microscopy, atomic force microscopy, adhesion test, humidity test and water contact angle (WCA) measurements. Thicknesses of the obtained films were about 800 nm. Incorporation of TEOS enhanced adhesion of film to substrate as well as improving stability of the film against water. WCA was seen to decrease, and porosity and surface roughness was seen to increase with increase in SiO2 nanoparticle content of the films. Increase in PEG molecular weight also resulted in a decrease in the WCA, thus WCA as low as 15 degrees was obtained. (C) 2012 Elsevier B.V. All rights reserved.Öğe Hydrothermal synthesis and characterization of nanocrystalline ZrO2 and surface modification with 2-acetoacetoxyethyl methacrylate(Springer, 2009) Sayilkan, Funda; Asilturk, Meltem; Burunkaya, Esin; Arpac, ErtugrulFor the utilization as inorganic/organic hybrid nanomaterials for optical purposes, nanocrytalline tetragonal ZrO2 was synthesized by hydrothermal method using zirconium(IV)-n-propoxide as precursor material. Surface of the ZrO2 particles was then modified with 2-acetoacetoxyethyl methacrylate used as a copolymer for coatings. X-ray diffraction analysis revealed that both ZrO2 and modified ZrO2 are in tetragonal crystalline phase. As proved by transmission electron microscope and particle size analysis, average particle sizes of ZrO2 and modified ZrO2 were found as 6.22 and 14.7 nm, respectively. ZrO2 powder was easily dispersed either in water or n-hexane. Ultraviolet diffuse reflectance spectrophotometer analysis for ZrO2 and surface modified ZrO2 showed that maximum absorption peaks are at 215 and 225 nm, respectively.Öğe IMMOBILIZATION OF GLUCOSE OXIDASE IN SILICA SOL-GEL FILM FOR APPLICATION TO BIOSENSOR AND AMPEROMETRIC DETERMINATION OF GLUCOSE(Soc Chilena Quimica, 2012) Demirkiran, Nizamettin; Ekinci, Ergun; Asilturk, MeltemIn this study, an electrochemical biosensor was developed by using a sol-gel coating solution. The modified platinum electrode used in the study was constructed by immobilization of glucose oxidase under a layer of sol-gel film. The sol-gel coating solution was prepared by using GLYMO, TEOS, and MTEOS. Electrochemical measurements were carried out amperometrically by determining hydrogen peroxide produced by the enzymatic reaction between glucose and glucose oxidase. The amperometric responses of the resulting enzymatic electrode to glucose were rapid. It was observed that the amperometric response of the enzymatic electrode was linear for glucose concentrations in the range from 2 to 18 mM with 50 s response time. LOD and LOQ for the enzymatic electrode were calculated to be 0.055 mM and 0.184 mM, respectively. It was determined that the developed biosensor had an acceptable reproducibility. The selectivity of the biosensor was determined in the presence of some interfering substances, such as lactose, sucrose, urea, uric acid, oxalic acid, and ascorbic acid. The stability of the biosensor was investigated, and it was found that the sensor response decreased by 59% of its initial response over a period of 30 days of storage in dry conditions at 4 degrees C.Öğe Photocatalytic antibacterial performance of Sn4+-doped TiO2 thin films on glass substrate(Elsevier, 2009) Sayilkan, Funda; Asilturk, Meltem; Kiraz, Nadir; Burunkaya, Esin; Arpac, Ertugrul; Sayilkan, HikmetPure anatase, nanosized and Sn4+ ion doped titanium dioxide (TiO2) particulates (TiO2-Sn4+) were synthesized by hydrothermal process. TiO2-Sn4+ was used to coat glass surfaces to investigate the photocatalytic antibacterial effect of Sn4+ doping to TiO2 against gram negative Escherichia coli (E. coli) and gram positive Staphylococcus aureus (S. aureus). Relationship between solid ratio of TiO2-Sn4+ in coatings and antibacterial activity was reported. The particulates and the films were characterized using particle size analyzer, zeta potential analyzer, Brunauer-Emmett-Teller (BET), X-ray diffractometer (XRD), SEM, AAS and UV/VIS/NIR techniques. The results showed that TiO2-Sn4+ is fully anatase crystalline form and easily dispersed in water. Increasing the solid ratio of TiO2-Sn4+ from 10 to 50% in the coating solution increased antibacterial effect. (C) 2008 Elsevier B.V. All rights reserved.Öğe Photocatalytic degradation of azo dye using core@shell nano-TiO2 particles to reduce toxicity(Springer Heidelberg, 2018) Ozmen, Nesrin; Erdemoglu, Sema; Gungordu, Abbas; Asilturk, Meltem; Turhan, Duygu Ozhan; Akgeyik, Emrah; Harper, Stacey L.Clean and safe water is fundamental for human and environmental health. Traditional remediation of textile dye-polluted water with chemical, physical, and biological processes has many disadvantages. Due to this, nano-engineered materials are drawing more attention to this area. However, the widespread use of nano-particles for this purpose may lead to photocatalytic degradation of xenobiotics, while increasing the risk of nano-particle-induced ecotoxicity. Therefore, we comparatively evaluated the toxicity of novel synthesized core@shell TiO2 and SiO2 nano-particles to embryonic stages of Danio rerio and Xenopus laevis. The ability of photocatalytic destruction of the synthesized nano-particles was tested using toxic azo dye, disperse red 65, and the effects of reducing the toxicity were evaluated. The reflux process was used to synthesize catalysts in the study. The samples were characterized by scanning electron microscopy, X-ray fluorescence spectroscopy, X-ray diffractometry, BET surface area, and UV-vis-diffuse reflectance spectra. It was determined that the synthesized nano-particles had no significant toxic effect on D. rerio and X. laevis embryos. On the other hand, photocatalytic degradation of the dye significantly reduced lethal effects on embryonic stages of the organisms. Therefore, we suggest that specific nano-particles may be useful for water remediation to prevent human health and environmental impact. However, further risk assessment should be conducted for the ecotoxicological risks of nano-particles spilled in aquatic environments and the relationship of photocatalytic interaction with nano-particles and xenobiotics.Öğe Photocatalytic degradation of Congo Red by hydrothermally synthesized nanocrystalline TiO2 and identification of degradation products by LC-MS(Elsevier, 2008) Erdemoglu, Sema; Aksu, Songuel Karaaslan; Sayilkan, Funda; Izgi, Belgin; Asilturk, Meltem; Sayilkan, Hikmet; Frimmel, FritzDegradation of Congo Red (CR) dye in aqueous solutions was investigated by means of photocatalysis of TiO2 which was hydrothermally synthesized at 200 degrees C in 2 h, in anatase phase with 8 nm crystallite size. Efficiency of TiO2 in photocatalytic degradation under visible irradiation was studied by investigating the effects of amount of TiO2, irradiation time, initial CR concentration and pH. It was found that complete decolorization is achieved within 30 min of irradiation. Effects of nitrate and sulphate ions and humic acid on the degradation were also tested. The results were compared with Degussa P-25 TiO2 at the same degradation conditions. Degradation products were detected using LC-MS technique. The probable pathways for the formation of degradation products were proposed. (C) 2008 Published by Elsevier B.V.Öğe Preparation of aluminum-doped zinc oxide (AZO) nano particles by hydrothermal synthesis(Springer, 2010) Burunkaya, Esin; Kiraz, Nadir; Kesmez, Oemer; Camurlu, H. Erdem; Asilturk, Meltem; Arpac, ErtugrulAluminum doped zinc oxide (AZO) nanometric particles were synthesized by hydrothermal method. Aluminum nitrate hydrate, aluminum sec-butoxide and zinc nitrate hydrate were used as the starting materials, and n-propanol and 2-butanol were used as solvents. Ratio of Al2O3 in ZnO was kept at 10 wt%. Reaction was conducted in a Teflon autoclave at 175-225 A degrees C for 5 h. Ratios of alcohol, H2O and HCl to zinc nitrate hydrate were altered and 6 different sets of parameters were investigated. Obtained products were subjected to powder-XRD, particle size measurement, TEM examination and AAS analysis. Single phase AZO particles were obtained at alcohol to zinc nitrate ratio of 35, acid to zinc nitrate ratio of 0.2, at 225 A degrees C. Particle size was determined as 3.2 +/- A 0.4 nm from TEM examinations and as 1-2 nm from dynamic light scattering. Synthesized particles have amphiphilic character, thus they can be dispersed in both polar and non-polar media. It was seen from the UV-diffuse reflectance spectra that the AZO powder had low reflectance in the UV region and high reflectance in the visible region. The obtained powder has the potential to be utilized in the form of thin films for optical and electronic purposes.Öğe Preparation of Sn doped nanometric TiO2 powders by reflux and hydrothermal syntheses and their characterization(Springer, 2011) Kiraz, Nadir; Burunkaya, Esin; Kesmez, Omer; Camurlu, Hasan Erdem; Asilturk, Meltem; Yesil, Zerin; Arpac, ErtugrulHydrothermal and reflux synthesis methods were utilized for the preparation of 5% Sn doped TiO2 nanopowders. Obtained powders were subjected to particle size and specific surface area measurements, flame atomic absorption spectroscopy, X-ray diffraction analyses and transmission electron microscopy examination. TiO2 powder prepared by hydrothermal synthesis presented a bimodal particle size distribution with average particle sizes of about 3 and 10 nm, whereas TiO2 powder synthesized by reflux method had an average particle size of 7 nm. Specific surface areas of hydrothermal and reflux synthesized TiO2 were 130 and 115 m(2)/g, respectively. Sn doping in TiO2 was 95.8% in hydrothermal and 86.4% in reflux synthesis as measured by FAAS, respectively. Photocatalytic activities of the obtained TiO2 powders were evaluated by decomposition of malachite green solution in a solar box. Photocatalytic activity of hydrothermally synthesized TiO2 was fairly higher in visible light and slightly higher in UV light than the activity of reflux synthesized TiO2.Öğe Preparation, Characterization and Photocatalytic Activities of TiO2-coated Activated Carbon Catalysts for Rhodamine B Photodegradation(Wiley-V C H Verlag Gmbh, 2015) Asilturk, Meltem; Sener, Sadiye; Sener, EnginTiO2-coated activated carbon (TiO2/AC) catalysts with high activity and easy separation were prepared by the coating method and their photocatalytic performances were studied for degradation of rhodamineB(RhB) dye. For this purpose, first, anatase TiO2 nanocrystal was prepared via sol-gel process of titanium(IV) isopropoxide (TTIP), followed by reflux treatment at a relatively low-temperature (130 degrees C) without further treatments. Second, four different amounts of AC were separately coated with TiO2 by dipping in TiO2 sol (10%, w/w) at room temperature. The catalysts were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area, and UV-vis diffuse reflectance spectroscopy (DRS). Coating AC with TiO2 produced catalysts with higher BET surface areas and greater crystallite sizes as compared to bare TiO2. RhB (50 mg/L) was almost completely discolored in 50 min, and the mineralization efficiency was 100% in 60 min for the catalysts containing 10 and 15% AC. Furthermore, all catalysts showed much higher photocatalytic activities than the commercial Degussa P-25.Öğe Roasting-Related Changes in Oxidative Stability and Antioxidant Capacity of Apricot Kernel Oil(Wiley, 2010) Durmaz, Goekhan; Karabulut, Ihsan; Topcu, Ali; Asilturk, Meltem; Kutlu, TuerkanApricot kernels were roasted for various lengths of time (0-30 min) at 180 A degrees C and changes in the oxidative stability, antioxidant capacity, color, as well as the level of tocopherols and fatty acids of the apricot kernel oil (AKO) were monitored. While the level of tocopherols decreased, the oxidative stability and antioxidant capacity of AKO increased with roasting, probably due to the formation of antioxidative Maillard reaction products (MRPs) during the roasting. Medium roasted samples (15-20 min) were found to be more resistant to oxidative deterioration. The oil from the 30-min roasted sample was more susceptible to oxidation compared to the oil from the 20-min roasted sample in most of the stability tests. Relatively shorter roasting periods (5-10 min) also led to a decrease in oxidative stability in comparison to the unroasted sample. Brownish color and antiradical activity increased with roasting and the highest values were measured in the 30 min roasted sample.Öğe Sol-gel synthesis of 3-(triethoxysilyl)propylsuccinicanhydride containing fluorinated silane for hydrophobic surface applications(Springer, 2010) Kiraz, Nadir; Burunkaya, Esin; Kesmez, Omer; Asilturk, Meltem; Camurlu, H. Erdem; Arpac, ErtugrulIn this paper, novel fluorinated silane compound was prepared by adding hydroxyl terminated Fluorolink D10H oligomer to 3-(triethoxysilyl)propylsuccinicanhydride. The obtained silane system was independently composed with 3-Aminopropyltrimethoxysilane, 3-Glycidyloxypropyltrimethoxysilane and 3-Glycidyloxypropyltriethoxysilane and, then the prepared coating solutions were applied to glass surface by spin-coating method. The chemical bonding between groups in system was investigated by Fourier Transform Infrared Spectroscopy analyses. The elemental composition of coatings was determined using Energy Dispersive X-ray Spectroscopy analyses. Its structure and surface properties were analyzed by scanning electron microscopy, atomic force microscopy, contact angle measurement and Ultraviolet-visible Absorption Spectroscopy. The amounts of fluorine on the coatings prepared with GF20-D10H-AMMO, GF20-D10H-GLYEO and GF20-D10H-GLYMO are 31, 32 and 34% at, respectively. Transparent coatings with smooth surface and uniform thickness were observed. The coatings had nanoscale roughness. The contact angles of coatings for water ranged from 88 to 107(o), and that of n-hexadecane ranged from 53 to 60(o).Öğe Sol-gel synthesis of IPTES and D10H consisting fluorinated silane system for hydrophobic applications(Springer, 2010) Burunkaya, Esin; Kiraz, Nadir; Kesmez, Omer; Asilturk, Meltem; Camurlu, H. Erdem; Arpac, ErtugrulIn this study, new fluorinated silane system was prepared by adding hydroxyl terminated Fluorolink D10H oligomer to 3-isocyanatopropyltrietoxysilane. The obtained silane system was independently composed with 3-Glycidyloxypropyltrimethoxysilane and 3-Glycidyloxy-propyltriethoxysilane. Then the prepared two different coating solutions were applied to glass surface by spin-coating method. The chemical bonding between groups in system was investigated by FTIR analysis. The elemental composition of coatings was determined by using EDX analysis. Their structure and surface properties were analyzed by scanning electron microscopy, atomic force microscopy, contact angle measurement and UV-vis spectrophotometer. The amounts of fluorine on the coatings prepared with IPTES-D10H-GLYEO and IPTES-D10H-GLYMO were 33 and 34 %wt, respectively. Transparent coatings with smooth surface and uniform thickness were obtained. The coatings had nanoscale roughness. The contact angles of coatings for water were range from 103A degrees to 110A degrees, and for n-hexadecane were range from 59A degrees to 62A degrees.
