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studied the kinetics of styrene oxidation over supported dodecatungstophosphate and undecaphosphotungstate using 30% aqueous H 2 O 2 as an oxidant. In the present article, we report the kinetic behavior of zirconia supported dodecatungstophosphate

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Abstract  

The influence of synthesis conditions on the properties of nanocrystalline boehmite catalysts was studied for styrene epoxidation reaction in liquid phase. At hydrothermal synthesis of boehmite, effects of pH, aging time and precursor aluminum salts were studied by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and total surface area. Characterization results showed that boehmite samples were in the nanosize range and single-phase with high crystallinity. Styrene epoxidation reaction in liquid phase was performed over boehmite catalysts at 80 °C in ethanol, using 30% aqueous hydrogen peroxide solution and urea + 30% aqueous hydrogen peroxide solution as oxidants. The progress of the reaction was followed by gas chromatography (GC). Higher styrene conversion and higher epoxide selectivities were achieved when urea was mixed with H2O2 solution. Boehmite catalyst samples aged for 8 h resulted in higher epoxide selectivities.

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Introduction Styrene, one of the most important intermediates of the chemical industry, is produced commercially by the dehydrogenation of ethylbenzene using Fe–K oxide based catalyst in presence of steam [ 1 , 2 ]. The

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combustibility of styrene–butadiene rubber. The results of these investigations have been compared with influence of montmorillonite modified by means of various organic compounds on the same properties of styrene–butadiene rubber

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composites containing different fillers were elucidated and compared. Experimental Materials Styrene–(ethylene butylene)–styrene (SEBS) triblock copolymer, Kraton G1650, with a styrene/rubber wt% ratio of 29

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new epoxy polyester materials. This paper presents the studies on the thermal and viscoelastic properties of novel epoxy-dicyclopentadiene-terminated polyesters-styrene copolymers. The influence of the structure of polyester and styrene content on the

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styrene polymers containing phosphorus or nitrogen/phosphorus moieties as pendants has been described [ 19 – 21 ]. Thermogravimetry TG was performed using a TA Instruments 2950 Hi-Res TG instrument interfaced with the

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[ 13 ]. In the previous study, we described the synthesis of new biocidal materials based on poly (chloromehtyl- p -styrene), in which the active organic compounds—hydantoin derivatives—were introduced instead of chlorine atoms in macro chains

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Journal of Thermal Analysis and Calorimetry
Authors: Zuzana Cibulková, Andrea Černá, Peter Šimon, Ján Uhlár, Karol Kosár, and Peter Lehocký

measurements were also successfully employed to study the antioxidant action of several p -phenylenediamines, p -substituted diphenyl amines, heterocyclic compounds, trisubstituted amines and triazine derivatives in styrene-butadiene rubber (SBR) [ 7 , 8

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Introduction ABS resin (styrene–butadiene–acrylonitrile) is one of the most successful engineering thermoplastics. It is widely used in the auto motive industry, telecommunications, business machines and consumer markets

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