Mitchell Winnik

Our research focuses on interfaces in polymer systems. It is widely believed that the properties of polymer systems depend in a crucial and often unknown way on events which occur within one molecular diameter of the phase boundary. Since polymers are large molecules, these interfaces or interphases can be 100 A thick or even larger. Our approach is to study polymer systems in which one component contains a fluorescent dye covalently attached at a specific site so that it will be located in the interface or interphase. This dye serves as a "molecular spy", reporting on what it experiences. It is then our job to relate this new information to the properties of the system as a whole, to make a connection between events which happen on a molecular scale, and the bulk properties of the system. One feature which makes our approach unique is that we must know how to prepare these different materials, and how to synthesize them with the right dye attached to the proper site in the polymer.

Many of our research projects are tied closely to issues in technology: how to understand the strength of the joint when two pieces of polymer are welded together, how to maintain the performance of paints and other coatings when they are made "environmentally friendly", how to model the formation of sludge in motor oil, how to understand the connection between structure and properties in polymer blends. In many of these projects, we work closely with scientists in industry and at other universities around the world. In this way we are able to study each problem with a wide variety of different techniques.