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Surface modification of nanosilica was done with a novel synthesized dipodal silane based on 3-aminopropyltriethoxysilane and γ -glycidoxypropyltrimethoxysilane. Then, it was used in a rigid polyurethane foam as reinforcing agent. The presence of two functional groups (-NH, -OH) on the nanosilica surface could help to better disperse nanosilica in a polymer matrix. Characterization and study of physical properties was performed by proton nuclear magnetic resonance spectroscopy ( 1 H-NMR), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), dynamic mechanical analysis (DMA) and thermomechanical analysis (TMA). Also a tensile test was done to evaluate static mechanical properties. In nano-filled samples, thermal and static mechanical properties were improved, but dynamic mechanical behavior declined, because the hard phase domain was restricted.

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3-Aminopropyltriethoxysilane (APTS) was used as coupling agent on the nanosilica surface and its effects on the physical properties of polyurethane rigid foam were compared with nanosilica modified with n-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAP). Characterization and investigation of properties were done by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, dynamic mechanical analysis and thermomechanical analysis. Also, the tensile properties were evaluated. In the case of nanocomposite based on APTS poor static mechanical properties and better dynamic mechanical properties were reported as compared with nanocomposite based on AEAP. Thus, AEAP with two functional groups reinforced the interfacial area and weakened the bulk matrix by disruption of the stoichiometry ratio.

A simple, convenient and novel method was developed for the recovery of bisphenol-A from polycarbonate wastes under microwave irradiation. In this study bisphenol-A was recovered at a 100% yield by using a mixture of glycerol/water as the green solvent and sodium hydroxide as the catalyst, respectively. This methodology can overcome the disadvantages existing in traditional methods such as long reaction times, high energy consumptions, use of harmful reagents and environmental problems, and is applicable to all types of polycarbonates.