Soft materials at surfaces and interfaces

在Dalnoki-Veress研究小组中，我们研究表面或界面处的软材料。这些材料包括聚合物、凝胶、泡沫、液晶以及生物物质。了解材料的基本性质，以及如何改善有利的性质，对新技术的发展至关重要。这些材料的一个令人惊讶的方面是，在小的长度尺度上，如薄膜或涂层，这些材料不一定表现出与大块材料相同的特性。薄膜性质的不同有几个原因：对于给定体积的材料，这些系统中的表面或界面要比体积大得多，而且分子也受到限制。薄膜为研究约束效应提供了一个方便的几何样本，以回答一个基本问题：当大分子被限制在一个比分子在整体中所占空间更小的空间中时，会发生什么？我们的努力可以概括为三个广泛和相互重叠的领域。首先，我们研究了薄膜的表面能和机械性能，并设计了独特的工具来实现这一目标。研究的材料范围从简单的聚合物薄膜到更复杂的系统，如生物细胞及其与修饰表面的相互作用。仔细的测量将使我们进一步了解这个在理论上仍然知之甚少、在实验上仍然具有挑战性的领域。在我们的第二个重点领域，我们感兴趣的是图案是如何自发形成的（自组装）还是以定向的方式形成的（图案或光刻）。我们试图理解这些模式出现的原因，例如：观察到的形态背后的基本物理原理是什么？一旦理解了控制形态的物理原理，我们希望能够控制形态的各个方面，从而制造出潜在的有用结构。我们感兴趣的第三个主要领域涉及聚合物分子（无定形和晶体）在密闭空间中的动力学。虽然我们希望我们的工作能够改进现有技术，但我们的主要长期目标是对局限于表面和界面的软材料有更全面的了解。

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.