This project supports collaboration by Dr. Frank Karasz, Professor of Polymer Science and Engineering at the University of Massachusetts, and two Turkish scientists: Dr. Bahattin Baysal, Director, Research Institute of Basic Sciences at the Marmara Research Centre (MRC), Gebze, Turkey and Dr. E. Elif Hamurcu, a Reserach Assistant at Bogazici University in Istanbul and also a Research Specialist in the Polymer Research Project at the MRC. The research deals with the transition of a polymer chain in dilute solution from an expanded coil in a good solvent to a collapsed, compact globular structure in a poor solvent. A comprehensive and quantitative understanding of chain collapse has not yet been achieved through experimental or theoretical means. The phenomena is intimately related to certain biological processes, including DNA folding and protein denaturation and tertiary structure formation. In this project the two scientists will use experimental techniques, including dynamic light scattering and viscometry, in detailed studies of coil collapse in near theta conditions for polar macromolecules in binary and ternary systems. Volume-phase transitions in network systems will also be investigated. Scope: This project brings together two scientists with excellent experiences and strong capabilities in research in the field of polymers. Dr. Karasz has investigated the helix-coil transition of polypeptides with calorimetric and scattering methods, and the conformational variation of linear and star, flexible and semiflexible macromolecules in solution as functions of molecular weight, concentration, architecture, ionic strength and confining geometry. Dr. Baysal has studied chain characteristics in dilute solution including coil-to-globule transition with theoretical analysis and viscometric and dielectric experiments. These complementary expertise provide for a logical combination of their research interests. A postdoctorate from MRC also will participate in the research at the U. of Massachusetts. The project meets the objectives of the Division of International Programs.
