Development of amino functionalized POSS based (3-Glycidoxypropyl)trimethoxysilane hybrid sol-gel coatings for aircraft applications

Varan, Dilara Çisel
An amino functionalized and 50 percent amphiphilic polyhedral oligomeric silsesquioxane (POSS) based (3-Glycidoxypropyl)trimethoxysilane (GPTMS) sol-gel reaction was carried out under extreme basic conditions. Amount of POSS per 1 mol of GPTMS was varied at molar ratios of 0.2, 0.4, and 0.6. The sol-gel product was coated on the aluminium 2024 alloy samples with immersion technique and thermally treated to improve corrosion resistance of the alloy. Influence of aging durations (1, 3, and 6 days) on the sol-gel reactions and polymerization of the coating layer were investigated using Fourier Transform Infrared (FTIR) spectroscopy. Thermal properties of the cured samples were analyzed by Differential Scanning Calorimetry (DSC) measurements and Thermo-mechanical analyzer (TMA). Surface properties and corrosion performance of the coatings were tested using contact angle measurement and Electrochemical Impedance Spectroscopy (EIS) techniques, respectively. A 0.6 mole amino functionalized POSS incorporated, and 6 days aged GPTMS revealed better corrosion resistance and hydrophobic features.


Development of pH Sensitive Alginate/Gum Tragacanth Based Hydrogels for Oral Insulin Delivery
Cikrikci, Sevil; Mert, Behiç; Öztop, Halil Mecit (2018-11-07)
Insulin entrapped alginate-gum tragacanth (ALG-GT) hydrogels at different ALG replacement ratios (100, 75, 50, 25) were prepared through an ionotropic gelation method, followed by chitosan (CH) polyelectrolyte complexation. A mild gelation process without the use of harsh chemicals was proposed to improve insulin efficiency. Retention of almost the full amount of entrapped insulin in a simulated gastric environment and sustained insulin release in simulated intestinal buffer indicated the pH sensitivity of ...
Rapid ionic liquid-supported nano-hybrid composite reinforced hollow-fiber electromembrane extraction followed by field-amplified sample injection-capillary electrophoresis: An effective approach for extraction and quantification of Imatinib mesylate in human plasma
Forough, Mehrdad; Farhadi, Khalil; Eyshi, Ali; Molaei, Rahim; Khalili, Hedayat; Kouzegaran, Vahid Javan; Matin, Amir Abbas (2017-09-01)
The focus of this study is development of a new, convenient, rapid and sensitive electromembrane extraction approach (based on an ionic liquid-supported MWCNTs/ZnO reinforced hollow fiber, for the first time) as an off-line sample clean-upipreconcentration method coupled with capillary electrophoresis (CE-UV) using field-amplified sample injection (FASI) for quantification of Imatinib mesylate in human plasma. The nano-hybrid sorbent, coated by 1-octyl-3-methylimidazolium bromide ionic liquid (E0M1m]Br) in ...
Covalent immobilization of invertase on chemically activated poly (styrene-2-hydroxyethyl methacrylate) microbeads
A carrier for invertase enzyme was synthesized from styrene (S) and 2- hydroxyethyl methacrylate (HEMA) in the form of microbeads. These poly (styrene-2-hydroxyethyl methacrylate), P(S-HEMA) microbeads were activated by epichlorohydrin (ECH) treatment for covalent immobilization. The free and immobilized invertase were assayed in the hydrolysis of sucrose to glucose, and the obtained results were compared. The optimum pH was 4.5 for free and 5.5 for immobilized invertase. The optimum temperature of invertas...
Synthesis of Phenanthroline-Functionalized Phosphazene Based Metallosupramolecular Polymers and Their Stimuli-Responsive Properties
SEÇKİN, TURGAY; Sezer, Selda; KÖYTEPE, SÜLEYMAN (2018-11-01)
A series of phenanthroline-functionalized phosphazene based metallo-supramolecular polymers (PFP-MSP) was synthesised using a two-step reaction strategy. In first step, three phenanthroline unit containing monomer (PFP-M) was prepared from 5,6-dihydroxy-1,10-phenanthroline and hexachlorocyclotriphosphazene by condensation reaction. Then, this PFP-M was reacted with different metal ion salts (Co, Ni, Cu, Fe, Eu, La, Tb, Lu ions) and resulting for the metallo-supramolecular polymers bearing phosphazene struct...
Development of Silicalite/Glucose Oxidase-Based Biosensor and Its Application for Glucose Determination in Juices and Nectars
Dudchenko, Oleksandr Ye; Pyeshkova, Viktoriya M.; Soldatkin, Oleksandr O.; Akata Kurç, Burcu; Kasap, Berna O.; Soldatkin, Alexey P.; Dzyadevych, Sergei V. (2016-02-03)
The application of silicalite for improvement of enzyme adsorption on new stainless steel electrodes is reported. Glucose oxidase (GOx) was immobilized by two methods: cross-linking by glutaraldehyde (GOx-GA) and cross-linking by glutaraldehyde along with GOx adsorption on silicalite-modified electrode (SME) (GOx-SME-GA). The GOx-SME-GA biosensors were characterized by a four-to fivefold higher sensitivity than GOx-GA biosensor. It was concluded that silicalite together with GA sufficiently enhances enzyme ...
Citation Formats
D. Ç. Varan, “Development of amino functionalized POSS based (3-Glycidoxypropyl)trimethoxysilane hybrid sol-gel coatings for aircraft applications,” M.S. - Master of Science, Middle East Technical University, 2021.