Polymer films of nanoscale thickness: linear chain and star-shaped macromolecular architectures
Bradley R. Frieberg, Peter F. Green, Emmanouil Glynos
Applications of polymer thin films range from active and passive coatings to flexible electronics and energy conversion. During the last decade substantial efforts have been devoted toward understanding the physical properties of polymer thin films, where entropic effects associated with confinement of these macromolecules, and intermolecular interactions between these large molecules and the external interfaces, govern the average physical properties of these materials. While research in this area has been primarily limited to linear-chain polymers, it has recently been shown that polymers of very different architectures, specifically branched star-shaped polymeric molecules, provide advantages over those of linear- chain polymers. This is largely because the structure and hence properties such as wetting, aging and vitrification, may be manipulated appreciably only by altering the number of chains extending from the branched point of the macromolecule, without changing the chemistry. In this prospective we review recent experiments and simulations that provide fundamental insights into the structure and interfacial behavior of star-shaped macromolecules and implications on the physical properties and hence applications of these materials.