Neha P. Ingole; Pravin G. Ingole
Abstract
In this paper we studied the synthesis of polymer membrane materials and their characterization by various techniques such as Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), CHNS/O analysis, scanning electron microscopy (SEM), and performance in the form of volumetric ...
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In this paper we studied the synthesis of polymer membrane materials and their characterization by various techniques such as Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), CHNS/O analysis, scanning electron microscopy (SEM), and performance in the form of volumetric flux and salt rejection. Herewith we have discussed about these techniques simply in details. The techniques are discussed as follows along with examples. Herewith we used polysulfone (PSf) membrane as a support membrane for our studies and we use all aforementioned techniques for polymer membrane characterizations. Thin film composite (TFC) membrane was prepared via interfacial polymerization (IP) on the surface of PSf membrane. The selective layer was prepared by the interfacial polymerization of 1, 3-benzenedithiol (BDT), and trimesoyl chloride (TMC) for water purification and the results have been discussed well in this paper. The result indicated that volumetric flux depends on the hydrophilicity of thin film. BDT 2 wt % and TMC 0.1 wt % solutions were found appropriate for high performance membrane. Such membrane exhibited 98.3 % salt rejection and as high as 79 L m 2 h water flux.
Suyog M. Pethe; Subhash B. Kondawar
Abstract
One dimensional conducting polymer nanostructures have been the focus of quite extensive studies worldwide due to their high aspect ratio, high porosity apart from high surface area to volume ratio. Conducting polyaniline nanofibers can be synthesized by various methods. In this paper, we report the ...
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One dimensional conducting polymer nanostructures have been the focus of quite extensive studies worldwide due to their high aspect ratio, high porosity apart from high surface area to volume ratio. Conducting polyaniline nanofibers can be synthesized by various methods. In this paper, we report the preparation of polyaniline nanofibers with an average diameter of 40–70 nm by two different simple approach rapid mixing and interfacial polymerization. The key to producing polyaniline nanofibers is to suppress secondary growth. Based on this, interfacial polymerization and rapidly mixed reactions have been developed that can readily produce nanofibers by slightly modifying the conventional chemical synthesis of polyaniline without the need for any template or structural directing agent. Synthesized polyaniline (PANI) nanofibers were characterized by FTIR spectroscopy, X-ray diffraction, transmission electron microscopy for their structural and UV-Vis absorption spectroscopy for optical properties. Direct and indirect transition energy gaps were determined from their Tauc plots. The absorption spectra show a linear fit for the transition. Electrical properties of the synthesized polyaniline nanofibers have been studied and the Arrhenius plots of electrical conductivity for the samples synthesized by rapid mixing and interfacial polymerization method show an approximate equal in their activation energy. The results obtained from optical and electrical properties are well compared, correlated and explained with respect to interfacial and rapid mixing polymerization techniques.
Subhash B. Kondawar; Suyog M. Pethe
Abstract
Intrinsically conducting polymers have been extensively studied due to their fascinating electronic properties and potential applications. One dimensional conducting polymer nanostructures have been the focus of quite extensive studies worldwide due to their high aspect ratio, high porosity apart from ...
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Intrinsically conducting polymers have been extensively studied due to their fascinating electronic properties and potential applications. One dimensional conducting polymer nanostructures have been the focus of quite extensive studies worldwide due to their high aspect ratio, high porosity apart from high surface area to volume ratio. In this paper, we report the synthesis of nanofibers of polyaniline and its substitute derivates and their comparative study in respect of electrical conductivity. Nanofibers of doped polyaniline (PANI), poly(o-methoxyaniline) (POMXA) and poly(o-methylaniline) (POMLA) were synthesized without need of any templates by interfacial polymerization. SEM, TEM, FTIR, UV-VIS and XRD were used to characterize the synthesized conducting polymeric materials. The average diameters of the synthesized nanofibers of conducting polymeric materials were in the range of 70-120 nm. The electrical conductivity was found to be in the range of 0.3 - 1.0 S/cm following the order as POMXA < POMLA < PANI which was found to be closely related to the size dependent electrical properties of the nanofibers. Optical band gap of these polymers was evaluated from UV–VIS absorption studies. Direct and indirect transition energy band gaps were determined from Tauc’s plots. Interfacial polymerization was shown to be readily scalable to produce bulk quantities of nanofibers of substitute derivative of polyaniline.
