This theoretical research grant will model self-organization in certain classes of incompatible multicomponent macromolecular systems. Analytical and numerical models will be developed to determine the conformation of self-organized aggregates of charged and/or multiblock macromolecules. Both, charged chains and multiblock molecules, are capable of forming highly organized self-assembled structures with specific functions. This is evident in the biological world, since nucleic acids and most proteins are charged and/or heterogeneous macromolecules. We will determine the structure of simpler self-organized macromolecules designed for specific functions. In particular, we will determine the structure and thermodynamics of dilute and semidilute charged polymer solutions in various ionic media. Flexible polyelectrolytes, such as single strand DNA and polysterene sulphonate, for example, can undergo reversible expanded to compacted transformations where the size of the chains changes by orders of magnitude with the addition of multivalent particles of opposite charge. This suggests their application as sensors. Polyelectrolyte semidilute solutions, on the other hand, form physical gels in the presence of multivalent particles. We will study the self-organization of these polyelectrolytes and of other complex multiblock molecules, such as triblocks of asymmetric crystallizable rigid rods, spacer and bulky oil chains. These triblock molecules, self-organized into mushroom shaped nano-aggregates, are the first examples of achiral pure (non-mixture) longitudinal ferroelectric liquid crystals. Models to explain this organization will be developed, and the possibility of supramolecular polar order in other complex chemical structures, including charged coil units, will be determined. Finally, the project on hydrodynamic flow in multicomponent incompatible fluids, initiated during the last funding period, will be completed. We will analyze the effect of flow in ternary fluids where the minority component segregates at interfaces forming vesicle-like droplets (wetting case) or forming a liquid droplet at the interfaces (non-wetting case) by using the code developed to study flow in multicomponent liquids of different viscosities. %%%

Agency
National Science Foundation (NSF)
Institute
Division of Materials Research (DMR)
Application #
0109610
Program Officer
G. Bruce Taggart
Project Start
Project End
Budget Start
2001-07-15
Budget End
2005-06-30
Support Year
Fiscal Year
2001
Total Cost
$195,000
Indirect Cost
Name
Northwestern University at Chicago
Department
Type
DUNS #
City
Evanston
State
IL
Country
United States
Zip Code
60201