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In this report the efficiency of organically modified nanosilica namely, ?-glycidoxy propyl trimethoxy silane / diethanol amine (GDS) was evaluated in the recovery of terephthalic acid from poly (ethylene terephthalate) wastes received from used soft-drink bottles. In this study, organically modified nanosilica used as the solid support, diethylene glycol (DEG) as the solvent and sodium hydroxide as the catalyst and the support performances was examined in detail and the results were compared with unsupported reaction. Results showed that (GDS) delivered good performance as the reagent and solid support in depolymerizing of poly (ethylene terephthalate) to the terephthalic acid. The highest terephthalic acid (86%) recovery yield was reached at NaOH (0.3 g), GDS (0.02 g) and PET: waste molar mass ratios (1:3), respectively. In addition, obtained data showed that in the presences of GDS (0.02 g) required reaction time for complete glycolysis decreases up 98% and by exceeding the GDS to 0.05 g, the consumption of the solvent decreases to 62.5% in comparison with unsupported reaction.

Synthesis and characterization of magnetic flexible polyurethane foam (PUF) nanocomposites is reported. In order to improving dispersion and preventing aggregation of Fe3O4nanoparticles in the polymer matrix, this material was modified by synthesized dipodal silane (ECA), the reaction product of 3-aminopropyltriethoxysilane (APTS) and γ-glycidoxypropyltrimethoxysilane (GPTS). The chemical structure of synthesized ECA was identified by nuclear magnetic resonance spectroscopy (1HNMR) and Fourier transform infrared spectroscopy (FT-IR), respectively. Magnetic flexible polyurethane foam nanocomposites prepared by the incorporation of ECA-modified Fe3O4nanoparticles and characterized by their apparent density, thermogravimetric analysis (TGA), magnetic properties analysis (VSM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and FT-IR spectra, respectively. The TEM and SEM images indicated that the nanoparticles were dispersed homogeneously in PUF matrix. Finally, it was confirmed that the thermal and magnetic properties of magnetic PUF nanocomposite depend on the amount of magnetic nanoparticles.

In this study, a new class of magnetic rigid polyurethane foams (PUFs) has been fabricated by one-shot process. Dipodal silane-coated magnetic nanoparticles (DScMNPs) was used as the magnetic nanoparticle and synthesized by functionalization of iron oxide nanoparticles by the prepared dipodal silane based on 3-aminopropyltriethoxysilane (APTS) and γ-glycidoxypropyltrimetoxysilane (GPTS) via sol-gel method. The synthesized DScMNPs were used up to 8.0% in the rigid polyurethane foam formulation and prepared foams were characterized. The chemical structure of DScMNPs was confirmed by proton nuclear magnetic resonance spectroscopy (1H NMR), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM), respectively. Morphological, thermal and mechanical properties of the PU nanocomposites were studied by scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). Vibrating sample magnetometery (VSM) was also showed that the synthesized PU nanocomposites are super paramagnetic.

Received polycarbonate wastes from used optical discs chemically recycled to Bisphenol- A by using water as the solvent, Cloisite 30B nanoclay and sodium hydroxide as the support and catalyst, respectively at convenient, green and eco-friendly conditions. The performances of the support in Bisphenol- A recovery yield were examined in comparison with the unsupported as well as nano-SiO2and nano-TiO2supported reactions. The optimum condition by having 90% recovery yield was found at 90 min when the reaction performed at equal waste/solvent ratio, catalyst 1% and nanoclay 2%.

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.

Flexible polyurethane nanocomposites (PUNCs) containing recycled polyether polyols received from chemical recycling of original corresponding foams were synthesized by the incorporation of organically functionalized Cloisite 30B montmorillonite (MMT). Different amounts of MMT (1-3%w) were added to the polyol mixture prior to introducing the isocyanate portion. Recycled polyol was ranged between 10 to 30% of total polyol and MMT was maximum 3%. Thermal, morphological and mechanical properties of prepared PUNCs were studied and the results demonstrated the improvement of properties.

Microwave‐assisted hydroglycolysis of poly(ethylene terephthalate) using an excess of methanol, ethanol, 1‐butanol, 1‐pentanol, and 1‐hexanol in the presence of different simple basic catalysts, namely, potassium hydroxide, sodium hydroxide, sodium acetate, and zinc acetate, is reported. Reactions were performed at short times without any side reactions, namely, oxidation of ethylene glycol. The products terephthalic acid and ethylene glycol were obtained in their pure form with sufficiently high yields with potassium hydroxide. The purified product was characterized by IR and nuclear magnetic resonance spectroscopy. The process of hydroglycolysis reported here is economically viable since yields of recycled products are high, and it has potential for further improvement to produce useful products. This process is of economic interest because much of the raw materials can be recovered and used for virgin PET resin synthesis. © 2007 Wiley Periodicals, Inc. Adv Polym Techn 25:242–246, 2006; Published online in Wiley InterScience (). DOI 10.1002/adv.20080

Glycolysis of isocyanate derived foams with glycol and amine mixture is a simple and economically attractive chemical recycling process. A mixture of diethylene glycol (DEG) and diethanol amine (DEA) is used as solvent system and sodium hydroxide as the catalyst. The obtained polyols can be completely reused in the formulation of integral skin foams in blend with virgin polyol.

A variety of enamines are easily and efficiently synthesised in short reaction times and moderate to high yields from corresponding acyclic and cyclic ketones using sulfuric acid–silica catalyst.

The reagent is easily synthesized in a nearly quantitative yield by the addition of Bn‐PPh3+Cl‐to a CH2Cl2solution of ICl.

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