Fluorine-Containing Dendrimers and Hyperbranched Polymers

Macromolecular structures of varying architectures have been prepared and studied, in order to gain a fundamental understanding of the role of molecular parameters upon the properties of polymeric materials and to lead to the development of unique and advanced materials. Improved knowledge of the structural conformation, three-dimensional solid-state packing, and physical and mechanical properties of highly-branched polymers has been gathered through several means of investigation, each involving the study of fluorine-containing dendritic or hyperbranched polymers. Dendritic tree-like macromolecules have been shown by several research groups to possess very interesting behavior, due to a three-dimensional globular shape, branched architecture and large number of chain end functionalities. By placing a fluorine atom at the focal point of the globular dendritic molecule, we have quantitatively determined the intramolecular location of the chain end groups relative to the remainder of the structure as being distributed throughout the internal and external regions, and have characterized the nature of intermolecular packing in the solid state. The micromechanical properties of ultra-thin film samples of dendritic macromolecules have been measured by atomic force microscopy, and comparisons have been made with linear polymers of exact compositional equivalence. This research then inspired the study of dendritic and hyperbranched polymers, which contained a high level of fluorocarbon groups to impart low surface energies and create minimally-interacting nanoscale globular molecules. Surface energies and adhesive forces lower than those for PTFE were accomplished, and these materials showed superior performance in applications such as mold release agents.