Reactivity ratio determination of newly synthesized copolymers from glycidyl methacrylate and tetrahydrofurfuryl acrylate

Copolymers from different feed compositions of glycidyl methacrylate (GMA) and tetrahydrofurfuryl acrylate (THFA) were synthesized using free radical polymerization in toluene solution at 70±1°C using benzoyl peroxide (BPO) as initiator. The polymers were characterized by 1H NMR,13C NMR and DEPT spectroscopic techniques. The copolymer compositions were determined using 1H NMR analysis. Reactivity ratios for GMA and THFA were determined by the Kelen-Tudos, Tidwell-Mortimer and error-in-variables model methods. The results showed that all these copolymerizations were strictly linear systems describable by the Mayo-Lewis equation based on the terminal model and that accurate reactivity ratio data can be obtained

Thermal and Tensile Properties of Treated and Untreated Red Balau (Shorea Dipterocarpaceae) Filled LDPE Composites

Red balau saw dust was heat-treated at 180°C and 200°C for one hour, extrusion compounded with Low Density Polyethylene (LDPE) at 20%, 40% and 60% volume fraction loadings and injection moulded. Thermal and tensile properties of the resultant composites were investigated as a function of filler loadings and treatment temperature. Increase in tensile moduli and decrease in tensile stress and strain were observed as filler loading and treatment temperature increased. Thermogravimetric analysis revealed an increase in degradation peak temperature of the composites from heat treated compared to the untreated wood composites. Differential scanning calorimetry revealed a decreasing trend in the degree of crystallinity (Xc) of the matrix when heat treated wood was used as filler. However, untreated wood showed an increase in Xc with increasing wood content

Plasticisation Effect on Thermal, Dynamic Mechanical and Tensile Properties of Injection-Moulded Glass-Fibre/Polyamide 6,6

Polymer composites of polyamide 6,6 reinforced with short glass fibre were prepared by injection moulding, conditioned under dry, 50% relative humidity and wet. Investigations by TGA, DSC, DMA and tensile tests were conducted. TGA results revealed that glass fibre loading in PA 6,6 improve the thermal stability of the composites. DSC analysis revealed that the incorporation of glass fibre and moisture into the PA 6,6 matrix resulted in a remarkable decrease in the degree of crystallinity. DMA results revealed the glass transition temperatures are sensitive to moisture absorption and their values move to a lower temperature upon exposure to moisture. Incorporation of glass fibre into the polyamide 6,6 gives rise to a significant improvement in tensile modulus and tensile strength, while tensile strain is reduced. Exposure to different environments from dry to wet conditions resulted in a decrease in the strength and modulus, while tensile strains decrease

Ionic Liquid Enhancement of Polymer Electrolyte Conductivity and their Effects on the Performance of Electrochemical Devices

Ionic liquids (ILs) are molten salts at ambient temperature and consist of poorly coordinating cations and anions. They have good electrical conductivity with a wide voltage window and high thermal stability, but negligible vapor pressure. ILs can enhance ionic conductivity when added to polymer electrolytes. Conductivity enhancement is due to the additional ions supplied by the IL, the plasticizing nature of the IL and the low viscosity that facilitates ion mobility. The plasticizing nature of ILs softens the polymer chain giving rise to easier polymer segmental motion. Increase in polymer segmental motion implies that IL can increase amorphousness of a polymer electrolyte (PE). This article discusses the involvement of ionic liquid as electrolytes in selected devices, namely dye sensitized photovoltaics, batteries, fuel cells and supercapacitors

(E,E)-1,2-Bis[4-(prop-2-yn-1-yl­oxy)benzyl­idene]hydrazine

The mol­ecule of the title compound, C20H16N2O2, is centrosymmetric with the mid-point of the central N—N bond located on an inversion center. The configuration around the C=N bond is E. The whole mol­ecule (except for the H atoms) is approximately planar, with an r.m.s. deviation of 0.07 Å. In the crystal, the presence of weak inter­molecular C—H⋯O hydrogen bonding involving each acetyl­ene H atom and the adjacent phen­oxy O atom results in the formation of supra­molecular chains

Surface characterizations of membranes and electrospun chitosan derivatives by optical speckle analysis

In this paper, we show that laser speckle pattern provides useful information toward revealing discrimination between nanofibers and membranes. Chitosan materials particularly organosoluble chitosan derivatives have a number of applications. The surface characteristics of these materials are very critical for specific applications. The analysis of laser speckles, both numerical and graphical, includes information about the surface structure. The development of digital electronics brought the ease of image processing and has opened new perspectives for a spectrum of laser speckle analysis (LASCA) applications. Our results show reasonable differences between the LASCA parameters of nanofibers and membranes. The methodology may be considered as a quantitative assessment tool for similar samples

(E,E)-1,2-Bis[3-meth­oxy-4-(prop-2-yn-1-yl­oxy)benzyl­idene]hydrazine

The complete mol­ecule in the title compound, C22H20N2O4, is generated by the application of an inversion centre. With the exception of the terminal acetyl­ene groups [C—O—C—C = −78.02 (17)°], the remaining atoms constituting the mol­ecule are essentially coplanar. The configuration around the C=N bond [1.282 (2) Å] is E. The formation of supra­molecular chains mediated by C—H⋯O inter­actions, occurring between methyl­ene H and meth­oxy O atoms, is the most notable feature of the crystal packing

One-step electrochemical deposition of PolypyrroleChitosanIron oxide nanocomposite films for non-enzymatic glucose biosensor

One-step electrodeposition method of Polypyrrole–Chitosan–Iron oxide (Ppy–CS–Fe3O4) nanocomposite films (Ppy–CS–Fe3O4NP/ITO) has been developed for the fabrication of advanced composite coatings for biosensors applications. The FESEM and EDX results provide the evidence of successful incorporation of Fe3O4 into Ppy–CS molecules. The presence of Fe3O4 nanoparticles in the nanocomposite films was further confirmed by the XRD and XPS spectrums. The fabricated electrode Ppy–CS–Fe3O4 NP/ITO shows a fast amperometric response with high selectivity to detect glucose non-enzymatically with improved linearity (1–16 mM) and the detection limit of (234 μM) at a signal-to-noise ratio (S/N=3.0)

Enhanced of Maltenes -Asphalt Blends Specifications via Thermal Catalytic Processes

Abstract: In this article the effects of using maltenes, which have been pre-separated recently from paraffinic base asphalt to modify asphalt pavement in variety of percentages has been investigated. Further modification has been performed by applying chlorine gas using ultra violet and ferric chloride as catalyst at certain temperature in order to increase the homogeneity and performance of paving asphalt. Characterization of asphalt blends has been performed according to ASTM standards. The results showed that addition of 1% of maltenes increases the softening point for the blends from catalytic chlorination, which reflects the benefit of this treatment. The penetration index for blends obtained by catalytic chlorination has also improved compared to unchlorinated samples and to those obtained from treating the asphalt with maltenes alone. Finally the specific gravity of catalytic chlorinated blends increased, thus indicating the influence of chlorination on the improvements of asphalt blends