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

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2021-12
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.

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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.