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Organic-Inorganic Materials (OIMs) have shown many promising applications in recent years including coating industry. This paper reports the preparation and characterization of a series of hybrid OIMs containing silica particles in which various amounts of 2-hydroxylethyl methacrylate (HEMA) have been co-polymerized with 3-methacryloxypropyltrimethoxy silane using a free radical co-polymerization reaction followed by a sol-gel process. The optical, thermal, mechanical and morphological properties of dip-coated films on glass slides were investigated by visible and FT-IR spectroscopy, hardness measurement, thermal analysis, scanning electron microscopy and atomic force microscopy. It was revealed that by increasing the amount of silane co-monomer, highly transparent coatings containing siloxane structure were formed in which the size of inorganic phase varied between 40 and 100 nanometers. Samples composed of 50 wt% silane co-monomer showed the highest hardness and solvent rub resistance. This may be attributed to the greater cross-linking density as a result of the complete hydrolysis and condensation of alkoxy groups. This was coincided with the higher temperature resistance of the nanocomposite coatings up to 340°C as found by thermo gravimetric analysis. The behavior of the resulting network was studied in the presence of Rhodamin 575 dye laser using fluorometric spectroscopy. The displacement of the maximum peak in emission spectra of the dye containing samples was discussed with respect to the structure of the nanocomposites. |