Role of polysaccharides as stabilizer/grafting agent during emulsion polymerization
Student Projects
Bachelor or Master theses are offered for this project. Please, contact the responsible researchers for detailed information
Project Objectives
- Understand the polysaccharide adsorption onto polymer particles
- Elucidate the presence and the impact of the polysaccharide grafting over a polymer
- Increase the stabilizing properties of the polysaccharide through chemical modification
Project Description
The project covers the investigation of the detailed reaction mechanism and kinetics of polymerization processes in the presence of polysaccharides as a low cost, renewable alternative to the ionic stabilizers.
As a first step, the project aims to elucidate the adsorption mechanism of the polysaccharide on the polymer particles. Evidences in the literatures shows also the possible grafting of the polysaccharides to the polymer chains leading to a system with an increased steric stabilization. However, the presence and the impact of this process over the polymerization reaction are still unclear. Then, the same approach adopted to evaluate the polysaccharide adsorption will be exploited to evaluate the impact of the grafting in the case of particles produced in the presence of polysaccharide. Specific experiments will be also performed to general reactivity of the polysaccharides. Experiments in aqueous solution using a free-radical initiator and water-soluble monomers will be monitored by NMR, aimed to follow the evolution of the system composition in terms of residual monomer/polysaccharide mixture. This way, we can to quantify the tendency of the polysaccharides to degrade as well as to form branches, reactions that could take place during the emulsion polymerization.
Finally, it will be explored the possibility to increase the polysaccharide efficiency increasing their hydrophobic character and thus their higher adsorptivity. This approach can be applied to introduce end groups bearing double bonds to the polysaccharide chain: this way, reactive stabilizers are obtained which could be incorporated/grafted on the particle surface, thus providing stronger stabilization. Experiments will be performed to identify the most effective route to modify the polysaccharides and their effectiveness in emulsion polymerization.
The project mainly focuses in the area of polymer reaction engineering covering different aspects (emulsion polymerization, adsorption, chemical modification) and various characterization techniques (UV, DLS, NMR, SEC, MALDI).
Contact Person: Raffaele Ferrari