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Abstract : Influence of Cobalt (II) Chloride Catalysed on the Thermal and Optical Characterization of PEO Based Solid Polymer Electrolytes
Influence of Cobalt (II) Chloride Catalysed on the Thermal and Optical Characterization of PEO Based Solid Polymer Electrolytes DOI: http://dx.doi.org/10.6000/1929-5995.2014.03.04.2 Published: 02 January 2015 |
Abstract: Solution-casting technique was employed for the preparation of solid polymer electrolyte based polyethylene oxide (PEO) with 0, 1, 3 and 5 weight percentage cobalt chloride (CoCl2) films were characterized by X-ray Diffractometry (XRD), Differrential Scanning Calorimetry (DSC), Scanning Electron Microscope (SEM) and Ultra Violet-Visible (UV-Vis.) Spectroscopy methods. The optical band gaps, absorption band edges and Urbach energy shows decrease with increasing of Co+2 ion concentration in the polymer matrix because of the formation of free radicals or cluster. The Thermogravimetry (TG) and Derivative Thermogravimetry (DTG) were used to examine the thermal stability of the film and it was found that the stability of the complexes is higher than that of the pure PEO due to the addition of CoCl2. The wavelength position of a fluorescence emission band varied by increasing of a dopant wt % of salt. Keywords: XRD, Optical band gaps, SEM, Fluorescence, Thermal stability.Download Full Article |
Abstract : Titanium Complex Containing a Saligenin Ligand - New Universal Post-Metallocene Polymerization Catalyst: Copolymerization of Ethylene with Higher α-Olefins
Pages 216-226 Laura А. Rishina, Svetlana S. Lalayan, Svetlana Ch. Gagieva, Vladislav А. Тuskaev, Alexander N. Shchegolikhin, Dimitri P. Shashkin and Yury V. Kissin DOI: http://dx.doi.org/10.6000/1929-5995.2014.03.04.3 |
Abstract: Copolymerization reactions of ethylene with three α-olefins, 1-hexene, 1-octene and 1-decene, were carried out with a new post-metallocene catalyst based on Ti complex with a bidentate saligenin-type ligand I and two co catalysts, MAO and a combination of AlEt2Cl and MgBu2. Ability of the I - AlEt2Cl - MgBu2 system to copolymerize α-olefins with ethylene is far superior to that of the I - MAO system. Reactivity of α-olefins in copolymerization reactions with ethylene decreases in the sequence: 1-hexene>1-octene>1-decene. Both catalyst systems, I - MAO and I - AlEt2Cl - MgBu2, contain several populations of active centers that greatly differs both in the average molecular weights and in composition of the copolymer molecules they produce. Active centers in both catalytic systems show significant tendency to alternate monomer units in copolymer chains. Keywords: Post-metallocene catalysts, molecular weight distribution, compositional distribution, differential scanning calorimetry, nuclear magnetic resonanc.Download Full Article |
Abstract : Flame Retardant and Mechanical Properties of Modified Paper Using Inorganic Salts for Packaging Applications
Flame Retardant and Mechanical Properties of Modified Paper Using Inorganic Salts for Packaging Applications DOI: http://dx.doi.org/10.6000/1929-5995.2014.03.04.4 Published: 02 January 2015 |
Abstract: The paper sheet prepared from unbleached rice straw containing different concentration of inorganic salts, that work as flame retardant additives (Lithium hydroxide one hydrate (LiOH.1H2O), Magnesium hydroxide (Mg (OH)2. 15H2O), aluminum sulphate (Al2(SO4)3) and calcium carbonate (CaCO3)) were investigated using horizontal burning test against flame retardant. Also, the prepared paper sheets were characterized using scanning electron microscope (SEM), thermal gravimetric analysis (TGA) and Infrared spectroscopy (IR). Furthermore, the water absorption was determined. In addition, the mechanical properties (breaking length, tear factor and burst factor) of the prepared paper sheet were evaluated. Correspondingly, the physical (structure and mechanical) properties of the prepared paper sheet were enhanced in terms of tensile, tear factor and water absorption. Also, delaying firing process will help in protecting the materials from burning, saving many of economic effect. So the prepared paper sheet can be used for different industrial applications especially in packaging applications. Keywords: Flame retardant, unbleached rice straw, paper sheet, packaging, SEM, TGA.Download Full Article |
Abstract : Comparative Degradation of LDPE, HDPE and HMHDPE under Different Soil Conditions
Comparative Degradation of LDPE, HDPE and HMHDPE under Different Soil Conditions DOI: http://dx.doi.org/10.6000/1929-5995.2014.03.03.5 Published: 06 November 2014 |
Abstract: The Present work includes, degradation of polyethylene under different environmental conditions to know the effect of physical, chemical and biological factors prevailing in those conditions on degradation of polyethylene. Plastic films viz., Low density polyethylene (LDPE), High density polyethylene (HDPE) and High molecular weight high density polyethylene (HMHDPE) each were incubated in three different conditions viz., black soil, sandy soil and red soil for a period of 3 months. The changes in the properties of plastic films after incubation was studied by change in the weight of the plastic film and mechanical parameters like tensile strength, breaking load and percentage of elongation. Among all the plastic films HDPE was found to be highly susceptible with 33% weight loss and 40% reduction in percentage of elongation compared to LDPE with 26% weight loss and 34 % reduction in percentage of elongation in black soil. Whereas HMHDPE found to be highly resistant in all the soils with no significant weight loss and percentage of elongation (15%). None of the plastic films had shown degradation in sandy soil even after incubation for 3 months. FTIR spectroscopy results showed that HDPE film incubated in black soil had undergone extensive degradation when compared with un incubated HDPE film. Keywords: Polyethylene, Environment, Polymer, Black soil, Degradation.Download Full Article |