Berlin 2018 – wissenschaftliches Programm
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 70: Crystallization, Nucleation and Self-Assembly II
CPP 70.11: Vortrag
Donnerstag, 15. März 2018, 18:00–18:15, C 230
Polymer self-assembly into nanoparticles through rapid solvent exchange in organic media — •Tatiana Morozova1, Victoria E. Lee2, Athanassios Z. Panagiotopoulos2, Robert K. Prudhomme2, Rodney D. Priestley2, and Arash Nikoubashman1 — 1JGU, Mainz, Germany — 2Princeton University, Princeton, USA
Polymeric nanoparticles (NP) are vital components for a wide range of applications, such as biomedical targeting and diagnostics. Recently, a new method to form monodisperse polymeric NPs was developed, which relies on the rapid micromixing of a polymer solution with a nonsolvent . Using this technique, stable NPs from hydrophobic polymer were fabricated in water without additional stabilizers. It was hypothesized that this peculiar stability might originate from electrostatic stabilization, mediated by the adsorption of hydroxide ions on the hydrophobic surface, water charge transfer effect, or possible impurities in the system. In order to elucidate the nature of the stabilization mechanism in the NP suspension, we conducted experiments using alternative organic nonsolvents instead of water, i.e. heptane and hexane. To our surprise, the polymers aggregated into stable NPs for a wide range of process parameters. We theoretically investigated possible explanations for this stability: steric, electrostatic stabilizations and conditional thermodynamic equilibrium. Our considerations suggest that electrostatic stabilization is the most likely candidate, but the source of the charge is still elusive as there are no obvious charge carriers in the system.