General field of research: Complex multicomponent systems based on natural and synthetic polyelectrolytes.
Main results of scientific research
- The development of a new, original method for the preparation of polymers with azobenzene groups covalently bound to the main chain starting from stoichiometric polycation/azo dye complexes, the distance between the macromolecular backbone and the ammonium groups being the major influence factor in the synthesis of such polymers with well-defined structure
- Surface modification by electrostatic self-assembly of polyelectrolytes or preformed non-stoichiometric polyelectrolyte complexes; application of composite membranes for selective separation of water from alcohols
- The preparation and application of non-stoichiometric polyelectrolyte complexes as stable colloidal dispersions based on synthetic and/or natural polyelectrolytes; highlighting the important role of the titrant addition rate on the characteristics of complexes and their colloidal stability; using dynamic light scattering and atomic force microscopy as complementary methods to describe the correct dimensional polyelectrolyte complexes in colloidal dispersion
- Preparation and characterization of CaCO3 microparticles doped with ionic polymers sensitive to pH variation and with negatively charged non-stoichiometric polyelectrolyte complexes
- The development of new (zwitter)ionic macromolecular structures, using efficient, economical fabrication procedures, and thus creating complex (composite) materials that can be used in environmental protection (sorbents with specific activity and/or selectivity, reusable) and medicine (biomedical devices, which can act as specialized antimicrobial and/or drug-carrier systems). Elucidate the role of the initial components (monomers, cross-linking agents, etc.) and the influence of various synthesis parameters on the structure and morphology of the new materials, leading to the development of new materials/specialized systems with (zwitter)ionic structure.
- Synthesis and characterization of grafted polymers by (a) grafting of monomers on polysaccharides (chitosan, gellan, xanthan, sodium hyaluronan, starch) or (b) grafting of macromolecules (e.g., zein, starch) on ionic cross-linked (zwitter)ionic microparticles, during or after their synthesis
- Testing of materials/composites in the retention of organic/inorganic pollutants from simulated water, wastewater or surface water: (a) testing, in static and dynamic experiments, of single/multi-component sorption/desorption of transitional metal ions; (b) testing in experiments of loading/release of organic pollutants (dyes, drugs, pesticides, humic acids, etc.); (c) testing in sorption/desorption experiments of mixtures of organic / inorganic pollutants dissolved in simulated and real water; (d) testing in column chromatography experiments by ion exchange or affinity.
Dr. Habil. Marcela Mihai 