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۱Effect of silica nanoparticles reinforcement on the properties of foams from high internal phase emulsion polymerizations
نویسنده(ها): ،
اطلاعات انتشار: سومین همایش ملی تحقیقات نوین در شیمی و مهندسی شیمی، سال
تعداد صفحات: ۴
Polymerized high internal phase emulsion (polyHIPE) filled with silica nanoparticles has been successfully prepared. The effect of silica nanoparticles weight fraction (1%, 3%, 5% and 10%) on the mechanical properties of a polyHIPE nanocomposite was studied. The anocomposite was produced by dispersion of 12 nm silica particles in the continous phase of the emulsion by ultrasonication. ethacryloxypropyltrimethoxysilane was added to the polymer matrix as a silane coupling agent in order to introduce the linkage between silica nanoparticles and polymer network, consequently to make certain that the silica particles were covalently incorporated into the polymer network. Stress–strain curves were plotted and have demonstrated that Young’s modulus as well as crush strength increased with raising weight fraction of silica nanoparticles. The Young’s modulus of silica reinforced foams increased by 178% and the crush strength by 225% in comparison to foams without reinforcement.<\div>

۲Highly Open Porous Emulsion‒Templated Monoliths: Effect of Electrolyte and Organoclay
نویسنده(ها): ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۸
Highly open porous polymer foams were prepared by polymerization of water–in–oil high internal phase emulsions (HIPEs) that contain styrene, acrylonitrile and divinylbenzene. The effect ofelectrolyte and two different contents of organo–modified montmorillonite (Cloisite30B, C30B) on the HIPE equilibrium torque values, an approximate characterization of HIPE viscosities, and the microstructure and properties of the resulting PolyHIPE foams were investigated. The resultsshowed by adding electrolyte to the aqueoues phase of the emulsion, torque fluctuations decreasedand the stability of the emulsion increased. Scanning electron micrographs exhibited an open–cell polyHIPE structure for all of the samples. The weigth–average diameter of the cells and intercellular windows of the foam without organoclay were 26.4μm and 7.7μm, respectively. Theintroduction of organoclay within the emulsion copolymer foam significantly decreased the mean size of cells and intercellular windows compared with the copolymer foam without reinforcement. According to compression results by using 1%wt C30B in the organic phase the Young’s module and crush strength of the sample increased about 33.5% and 171%, respectively<\div>

۳Effect of Porosity and Organocaly Level on the Ion–exchange Capacity of polyHIPE Membrane
نویسنده(ها): ،
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۸
Highly open–porous vinylbenzyl chloride\divinylbenzene (VBC\DVB) polyHIPE membrane containing various amounts of Cloisite30B (C30B) were synthesized successfully via polymerization of anconcentrated or high internal phase emulsion (HIPE).Amination process via using aqueous trimethylaminewas applied to obtain a functionalized porous anion–exchange nanocomposite membrane. The exchange capacity of nanocomposite membrane was determined by titration procedure. The effects of organoclay content and foam porosity have been investigated on the basis of ion exchange capacity of resultingnanocomposite membrane. The results showed that the prepared membranes possessed an ion–exchangecapacity in the range of 1.08–1.76 mequiv\g of dry membrane. Scanning electron micrographs exhibited an open–cell polyHIPE structure for all the organoclay–reinforced polyHIPE membranes. FTIR technique was also used to characterize the chemical structure of anion–exchange membrane.<\div>
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