Soft materials at surfaces and interfaces

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In the Dalnoki-Veress research group we study soft materials at surfaces or interfaces.  These materials include polymers, gels, foams, liquid crystals, as well as  biological matter. Understanding the material properties at a fundamental level, and how to improve favourable properties, is crucial to the development of new technologies. One surprising aspect of these materials is that on a small lengthscale, like thin films or coatings, these materials do not necessarily exhibit the same properties as bulk materials. Thin film properties differ for several reasons: for a given volume of material there is much more surface or interface in these systems when compared to the bulk, but also the molecules become confined. Thin films provide a convenient sample geometry in which to study confinement effects in order to answer the fundamental question: what happens to large molecules when they are confined to a space smaller than what the molecule would occupy in the bulk? Our efforts can be summarised under three broad and overlapping areas. First of all we study surface energy and mechanical properties of thin films and have designed unique tools to achieve this goal. The materials studied range from simple polymer films to much more complex systems like biological cells and their interaction with modified surfaces. Careful measurement will allow us to further our understanding of an area that is still theoretically poorly understood and experimentally challenging. In our second focus area we are interested in the how patterns form either spontaneously (self-assembly) or in a directed fashion (patterning or lithography). We try to understand why these patterns appear, for example: what basic physics underlies the observed morphology? Once the physics governing the morphologies is understood, we hope to control aspects of the morphology so that potentially useful structures may be made. Our third main area of interest deals with the dynamics of polymer molecules (amorphous and crystalline) in confined spaces. While the hope is that our work will result in improvements to existing technologies, our primary, long term goal is to obtain a more general understanding of soft-materials confined at surfaces and interfaces.