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Northvale, NJ, United States

Mahnaj T.,Long Island University | Mahnaj T.,Barr Pharmaceuticals Inc. | Ahmed S.U.,Barr Pharmaceuticals Inc. | Ahmed S.U.,Abon Pharmaceuticals Llc | Plakogiannis F.M.,Long Island University
Drug Development and Industrial Pharmacy | Year: 2011

Objective: The aim of this study was to investigate the efficiency of a homologous series of esters of dicarboxylic acid on ethyl cellulose polymer in terms of their glass transition temperatures (Tg). Methods: Ethyl cellulose polymer was plasticized with succinates (C-2), glutarates (C-5), adipates (C-6), pimelates (C-7), suberates (C-8), and sebacates (C-10) at different concentration levels. The film formation and physical state of plasticizers within the polymer were investigated and incompatibility of plasticizers was determined by nonhomogeneous system. Results: A decrease in Tg of the plasticized polymer was used as an indicator of plasticizing efficiency. Experimental Tg values were correlated with the theoretical ones predicted by Gordon-Taylor equation. Most of the experimental Tg values did not fit with the predicted ones. For all plasticizers (except succinates) the measured Tg was lower than calculated indicating negative deviation from the ideal behavior. Anti-plasticization was obtained with lower plasticizers concentration. Fourier transform infrared spectroscopy was used to determine the interactions between the polymer and plasticizers on Tg values in predicting the efficiency. Conclusions: The correlation between experimental and calculated Tg values verifies that physiochemical properties are the primary factors influencing the plasticization efficiency. However, further studies are needed to establish the plasticization efficiency. © 2011 Informa Healthcare USA, Inc. Source


Hossain M.A.,Long Island University | Hossain M.A.,Teva Pharmaceuticals United States | Ahmed S.U.,Abon Pharmaceuticals Llc | Plakogiannis F.M.,Long Island University
Drug Development and Industrial Pharmacy | Year: 2012

The objective of this study was to investigate the effect of vehicle systems, pH and enhancers on the permeation of a highly lipophilic basic drug aripiprazole (ARPZ) through human cadaver skin. Solubility of ARPZ in single, binary, tertiary, and quaternary vehicle systems of N-methyl pyrrolidone (NMP), dimethyl sulfoxide (DMSO), water, ethanol and isopropyl myristate (IPM) was studied. Gel formulations of 5% ARPZ were developed with 0.5% Carbopol 971P in quaternary vehicle systems consisting of NMP, DMSO, water and ethanol or IPM at optimum ratio of 40/40/5/15. The effect of pH of the gel formulations and fatty acids with different chain lengths on the permeation was studied. The flux of ARPZ from gel formulation with IPM and ethanol was comparable. A four fold increase in APRZ flux was observed when the pH of the gel systems was lowered from pH 8.2 to pH 6 or pH 7. For fatty acids, the order of flux is lauric acid > myristic acid > caprylic acid > oleic acid. In all the cases, in vitro permeation rate of ARPZ through human cadaver skin followed zero order kinetics. This study demonstrated that ARPZ in tertiary vehicle system of NMP/DMSO/water/IPM at ratio of 40/40/5/15 and gel system of Carbopol 971P with pH 7 is a promising candidate for transdermal delivery. © 2012 Informa Healthcare USA, Inc. Source


Ning S.,Beijing University of Chemical Technology | Yang S.,Beijing University of Chemical Technology | Wei X.,Beijing University of Chemical Technology | Wang W.,Abon Pharmaceuticals Llc | And 2 more authors.
Journal of Applied Polymer Science | Year: 2012

Hydrogenation of polymer having C=C double bond can be carried out with the metal-organic complex as catalyst, which has the property of themoregulated phase transfer. In this study, a new complex RhCl[PPh[(OCH2CH 2)5âcirc6CH3]2]3 (Rh/AEOPP) was synthesized with a good yield, which was further used as catalyst to selectively hydrogenated nitrile-butadiene rubber (HNBR). This is the first time that Rh/AEOPP complex was synthesized and applied in nitrile-butadiene rubber (NBR) hydrogenation. The result shows that hydrogenation degree of product (HNBR) can be extended to 90%, when the condition is [Cat] = 3% (based the weight of NBR), L2: Cat (Weight Ratio) = 2, [NBR] = 5% (based on the weight of xylene solution), P (H2) = 1.5 MPa, T = 155°C, and t = 8 h. Also, by adjusting temperature, the catalyst could be easily separated from products with 89% catalyst complex recovery. In addition, 1H-NMR and infrared (IR) spectra showed that C=C double bonds in NBR was successfully hydrogenated without causing reduction of the CN group. © 2011 Wiley Periodicals, Inc. Source


Wang Z.,Beijing University of Chemical Technology | Lu Y.,Beijing University of Chemical Technology | Liu J.,Beijing University of Chemical Technology | Dang Z.,Beijing University of Chemical Technology | And 2 more authors.
Journal of Applied Polymer Science | Year: 2011

In this article, nano-zinc oxide (ZnO) filled ethylene propylene diene monomer (EPDM) composites are prepared, and the mechanical (static and dynamic) properties and thermal conductivity are investigated respectively, which are further compared with the traditional reinforcing fillers, such as carbon black and nano-silica. Furthermore, influence of in-situ modification (mixing operation assisted by silane at high temperature for a certain time) with the silane-coupling agent Bis-(3-thiethoxy silylpropyl)-tetrasufide (Si69) on the nano-ZnO filled composites is as well investigated. The results indicate that this novel reinforcing filler nano-ZnO can not only perform well in reinforcing EPDM but can also improve the thermal conductivity significantly. In-situ modification with Si69 can enhance the interfacial interaction between nano-ZnO particles and rubber matrix remarkably, and therefore contribute to the better dispersion of filler. As a result, the mechanical properties and the dynamic heat build-up of the nano-ZnO filled composites are improved obviously by in-situ modification, without influencing the thermal conductivity. In comparison with traditioanl reinforcing fillers, in-situ modified nano-ZnO filled composites exhibit the excellent performance in both mechanical (static and dynamic) properties and better thermal conductivity. In general, our work indicates that nano-ZnO, as the novel thermal conductive reinforcing filler, is suitable to prepare elastomer products serving in dynamic conditions, with the longer expected service life. © 2010 Wiley Periodicals, Inc. Source


Wang Z.-H.,Beijing University of Chemical Technology | Lu Y.-L.,Beijing University of Chemical Technology | Liu J.,Beijing University of Chemical Technology | Dang Z.-M.,Beijing University of Chemical Technology | And 2 more authors.
Polymers for Advanced Technologies | Year: 2011

In this paper, nanoalumina (Al2O3) highly filled ethylene propylene diene monomer (EPDM) composites are prepared, and the mechanical (static and dynamic) properties and thermal conductivity are investigated systemically through various characterization methods. Furthermore, influences of in situ modification (mixing operation assisted by silane at high temperature for a certain time) with the silane-coupling agent bis-(3-triethoxy silylpropyl)-tetrasulfide (Si69) and stearic acid (SA) pretreatment on the nano-Al2O3 filled composites are as well investigated. The results indicate that nano-Al2O3 particles can not only perform well in reinforcing EPDM, but also improve the thermal conductivity significantly. Assisted by in situ modification with Si69, the mechanical properties (especially dynamic mechanical properties) of the nano-Al2O3 filled composites are improved obviously, without influencing the thermal conductivity. By comparing to the traditional reinforcing fillers, such as carbon black (grade N330) and silica, in situ modified nano-Al2O3 filled composites exhibit excellent performance in mechanical (static and dynamic) properties as well as better thermal conductivity, especially lower compression heat build-up and better fatigue resistance. In general, our work indicates that nano-Al2O3, as the novel thermal conductive reinforcing filler, is suitable to prepare rubber products serving in dynamic conditions, with the longer expected service life. © 2010 John Wiley & Sons, Ltd. Source

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