Akshay S. Kulkarni; Geeta Shirnalli; Ashok M. Sajjan; Nagaraj R. Banapurmath; Ashok S. Shettar; Kartik J. Uttarkar
Abstract
A solution technique was adopted to develop membranes in which chitosan-wrapped silver nanoparticles (CS-wrapped Ag nanoparticles) were incorporated in poly(vinyl alcohol) (PVA). The morphological studies and the chemical compositions of the prepared membranes were investigated using the characterization ...
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A solution technique was adopted to develop membranes in which chitosan-wrapped silver nanoparticles (CS-wrapped Ag nanoparticles) were incorporated in poly(vinyl alcohol) (PVA). The morphological studies and the chemical compositions of the prepared membranes were investigated using the characterization techniques like Infrared Spectroscopy, Differential scanning colorimetry, Wide Angle X-ray Diffraction, Thermogravimetric analysis and scanning electron microscopy. The effects of CS-wrapped Ag nanoparticles on membrane swelling were systematically studied to know the gas separation performance of the membranes. TGA showed increased thermal stability of Ag-nanoparticles incorporated PVA membranes nearly twice that of plane PVA membranes. Further, SEM revealed that CS-wrapped Ag nanoparticles incorporation into the PVA membrane matrix showed good compatibility and high swelling properties.
Ranu Pal; Sandeep Kumar Singh; M.J. Akhtar; Kamal K. Kar
Abstract
Efforts to use microwaves in material processing are gradually increasing. However, the phenomenon associated with the processing is less understood. The conversion of electromagnetic energy into heat depends largely on the dielectric properties of the material being treated. Therefore, the fundamental ...
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Efforts to use microwaves in material processing are gradually increasing. However, the phenomenon associated with the processing is less understood. The conversion of electromagnetic energy into heat depends largely on the dielectric properties of the material being treated. Therefore, the fundamental knowledge of these properties is essential for processing of materials using microwaves. In this study, first the dielectric evolution of silicon carbide (SiC) infused epoxy nanocomposites prepared at room temperature with 0-0.3 wt% content of SiC was measured. Secondly, the dielectric properties of the prepared nanocomposites after heating for 10 min in microwaves at a power of 500 W were investigated in order to see the effect of microwave curing. The dielectric properties of all the samples were measured at the microwave frequency of 2.45 GHz using the advanced cavity perturbation method attached to a vector Network Analyzer (VNA). The results indicate that the dielectric properties of the resultant nanocomposites increase with the increase in SiC content as compared to the neat epoxy sample. However, the dielectric properties were found to be decrease after microwave curing signaling the maximum possible extent of curing. This indicates that reinforcement of SiC nanoparticles in epoxy makes them ideal candidates for efficient microwave curing of nanocomposites. Lastly, the determination of thermal properties also confirms the maximum possible extent of curing of epoxy using SiC as nanofillers. Copyright © 2018 VBRI Press.
