Synthesis, characterization and applications of xanthan gum based synthetic polymers in organic and inorganic contaminations removal from aqueous solution

Abstract : This thesis involves the hybridization of xanthan gum (XG) with vinyl monomers for their application in the adsorption of synthetic dyes and metal ions from aqueous solution. Nanostructured materials were incorporated within the XG-based hydrogel networks to achieve hydrogel nanocomposites with tailored functionality. Carbon based nanomaterials (multi-walled carbon nanotubes (MWCNTs), reduced graphene oxide (rGO)) and ceramics (silicon dioxide (SiO2)) were incorporated within the hydrogel networks. The applicability of the prepared hydrogel nanocomposites as adsorbents were investigated for adsorption of methylene blue (MB), methyl violet (MV) and cadmium(II) in batch absorption experiments. XG-based absorbent was prepared via microwave-assisted free radical graft co-polymerization of poly acrylic acid (PAA) onto XG (mwXG-g-PAA). The structure, morphology and thermal stability of XG and mwXG-g-PAA were carried out by means of modern analytical methods such as 1H NMR, FTIR, SEM, XRD and TGA. The synthesized graft co-polymer was appliedfor cationic MB dye removal from aqueous solution. This adsorbent exhibited excellent adsorption ability towards MB under basic condition of pH 10. The results demonstrate xanthan gum grafted poly acrylic acid can be used as absorbent for removal of toxic dyes from wastewater. Xanthan gum-cl-poly acrylic acid (XG-cl-pAA) hydrogel and xanthan gum-cl-poly acrylic acid /oxidized-MWCNTs (XG-cl-pAA/o-MWCNTs) hydrogel nanocomposite were synthesized by microwave-assisted copolymerization, in which N,N′-methylenebisacrylamide (MBA) was used as a cross-linking agent. FTIR, SEM, XRD and TGA techniques were used to verify the structure, morphology and thermal stability of the prepared materials. These adsorbents were then examined for the adsorption of MB from aqueous solution. The effects of pH, contact time and equilibrium concentration on the MB dye adsorption were investigated in batches. The results revealed that XG-cl-pAA/o-MWCNTs hydrogel nanocomposite could be employed as a potential candidate in the remediation of MB contaminated wastewaters. In addition, the adsorption-desorption cycle of XG-cl-pAA/o-MWCNTs hydrogel nanocomposite was repeated several times without significant loss of adsorption capacity...Ph.D. (Chemistry

Poly(ε-caprolactone) based bionanocomposites for food packaging application

M.Sc. (Chemistry)Please refer to full text to view abstract

Polymer-Based Hybrid Nanoarchitectures for Cancer Therapy Applications

Globally, cancer is affecting societies and is becoming an important cause of death. Chemotherapy can be highly effective, but it is associated with certain problems, such as undesired targeting and multidrug resistance. The other advanced therapies, such as gene therapy and peptide therapy, do not prove to be effective without a proper delivery medium. Polymer-based hybrid nanoarchitectures have enormous potential in drug delivery. The polymers used in these nanohybrids (NHs) provide them with their distinct properties and also enable the controlled release of the drugs. This review features the recent use of polymers in the preparation of different nanohybrids for cancer therapy published since 2015 in some reputed journals. The polymeric nanohybrids provide an advantage in drug delivery with the controlled and targeted delivery of a payload and the irradiation of cancer by chemotherapeutical and photodynamic therapy

Influence of phthalocyanine nanowire dye on the performance of titanium dioxide-metal organic framework nanocomposite for dye-sensitized solar cells

In clean energy, dye-sensitized solar cells (DSSCs) have become a key tool for the photovoltaic effect. Copper phthalocyanine nanowire (CuPcNW) dyes can be used in DSSCs to generate low-cost devices, light-harvesting, fast electron transfer materials, and prevent recombination processes, as well as improve conductivity. This study investigates the effect of CuPcNW dye on TiO2, MOF, and TiO2-MOF in photovoltaic performance. Electrochemical characterizations such as cyclic voltammetry and electrochemical impedance spectroscopy (EIS) have also revealed the half-wave peak potentials of the ternary nanocomposite with values of 0.44 and 0.35 V for the oxidation and reduction reversible reactions. The EIS behavior revealed the improved conductivity of the nanocomposite with a value of 244 µS/cm. It was seen that the TiO2-MOF/CuPcNW nanocomposite achieved a maximum power conversion efficiency of 6.467 % owing to the presence of CuPcNW, which improved the photocurrent density, faster electron transport, and reduced charge recombination in the nanocomposite