dr. Albena Lederer : Advanced Separation and Characterization of Multifunctional Polymer Systems
| When: | Mo 12-05-2014 10:30 - 11:30 |
| Where: | 5116.0136 |
ABSTRACT
The application area of functional materials is growing rapidly following new directions, in which precisely tuned molecular properties are needed. This trend is based on the versatility, tunability and high functionality of soft materials like highly branched, responsive or dynamic polymer systems and their well-defined nanometer-sized structure. The understanding of these materials on a molecular level and how to tune their scaling parameters is crucial for the design of advanced applications. In the focus of our research is the development of in-situ and multidimensional separation of complex macromolecular systems.
Dendritic macromolecular architectures are of great industrial interest due to their high functionality and advantageous rheological features. Hyperbranched polymers as a particular example are product of simple statistical polymerization, which results in multiple distributions making their physicochemical characterization challenging but highly needed. We combine portfolio of model polymers with advanced characterization techniques to get an insight into structure-property relationships and to find new ways for a general description of the scaling theory. Light scattering, viscosity, hyphenated chromatographic separations, MD simulations and last but not least SANS help us to understand and describe self-similarity, fractal dimensions, as well as local molecular structure. Finally, this complex dendritic study enables us to find new approaches for a robust, multidimensional separation of dendritic macromolecules.
The question of interaction of dendritic biomacromolecules and biohybrid systems is highly relevant for biological applications. Functionalized amphiphilic, core-shell or dendronized polymers lead to complex host-guest systems, bioconjugate and bioaggregate distributions which need in-situ characterization of the scaling parameters depending on pH or concentration. Alternative, smooth separation approaches as the field flow fractionation (asymmetrical flow, AF4) with a variety of hyphenation possibilities are appropriate for this purpose. Using AF4 coupled to static light scattering, dynamic light scattering as well as using complementary methods such as AFM, cryo TEM and MD simulations we can shed light on the interaction profile of these dendritic structures.