Chemistry Weekly Seminar- PhD Candidate Asghar Dolatkah
Asghar Dolatkah, , PhD Candidate, will present a seminar at 4:00 p.m. in Thorvaldson 271.
Title:
Investigation of Polymer Nanocomposites for Dye Treatment in Aqueous Solutions
Abstract:
The objective of my research is fabrication of inexpensive stimuli-responsive nanocomposites with overall high performance for dye removal in aqueous solutions. Therefore, three types of stimuli-responsive nanocomposites including: i) nanocomposites with pH and magneto-responsiveness, ii) nanocomposites with redox-responsiveness and, iii) nanocomposites with salt-responsive self-assembly and adsorption were investigated.
In this talk, two approaches of dye treatment, i.e. adsorption and catalytic reduction, will be presented. Using chitosan as a biodegradable abundant biopolymer, polymer brush nanocomposites containing pH-responsive polyacid side chains with switchable dye uptake were designed. Polymer brush nanocomposites reveal superior adsorption performance and switchable behavior toward methylene blue in aqueous solution. In the second part, by interfacing silver nanoparticles with redox-responsive polyaniline (PANI), its catalytic activity toward reduction of p-nitrophenol to p-aminophenol was greatly enhanced through a modification of electronic structure in polymer template. In the third section, I will talk about selective cation dye binding affinity of polyaniline nanocomposites. PANI demonstrated to possess salt-responsive behavior and its interaction with salt led to polymer disassembly by weakening intermolecular hydrogen bonding and changes to the physicochemical properties of PANI in its doped state. Lastly in order to fully understanding dye/salt binding mechanism, responsive intramolecular hydrogen bonding was exploited to develop PANI capsules with responsive chemical gates and activatable-release of self-healing agents.