Polymer nanodroplet adsorption: continuum theory and computer simulation

Abstract

Compared to the solid and gaseous phases, liquids are more closely related to biological processes and the life sciences. In fact, it is generally believed that abiogenesis occurred in the liquid environment of the primordial sea which, itself, was formed only when appropriate conditions came to prevail on the young Earth, providing a striking illustration of the marginal character of the liquid state, in contrast with the solid and gaseous phases of the same substances, which exist over much wider ranges of temperature and pressure: the liquid state arises from a delicate balance between packing of molecules and cohesive forces or, more formally, between entropy and energy. The importance of a full quantitative understanding of liquids is only obvious. Following research in simple liquids, a new area of complex liquids emerged for the study of systems which exhibit ow, but whose liquid-like behaviour cannot be explained by the standard one-body picture used in simple liquids, as interatomic forces are significantly different from the hard-sphere type. The term complex liquid can be interchangeably used with complex fluid or soft matter - following P.G. de Gennes. Many examples of complex liquids involve the mixing of different phases, be they fluid or not in their own right, such as solid and liquid (to make up gel or sol), liquid and gas (to make up foam or liquid aerosol), and solid and gas (to make up solid foam or solid aerosol). Under appropriate conditions, these complex liquid examples, known as colloids, will exhibit fluid-like behaviour on the macroscopic scale. Further examples of complex fluids include polymers and liquid crystals. This Thesis focuses on polymers. Specifically, it researches polymers from a theoretical and a computer simulation perspective, in particular their interaction with surfaces in such a way that they become adsorbed. Setting out with a definition, examples of polymers, and a brief discussion of the practical applications of this work, the General Introduction gives an overview of the theoretical progress in the area of polymer adsorption. This sets the context for a subsequent description of the objectives of this Thesis. The General Introduction closes with an outline of the remainder of the chapters that follow.