Solution-phase assembly of nanoparticles and amphiphilic polymers: Controlling the morphology from vesicles to micelles

Advances in nanocomposite solution-phase assembly involve understanding fundamentally how nanoparticles influence the self-assembly structure of block copolymers. Researchers have shown that self-assembly of amphiphilic block copolymers and nanoparticles offers a powerful route to the formation of multifunctional nanocomposites for medical imaging and drug delivery applications. The possible combinations of various types of nanoparticles and polymers are numerous, but until recently the major factors that control these structures have not been well understood. Work done by others and the work in this thesis have shown that the arrangement of nanoparticles within a polymer matrix affects the composite material\u27s properties in ways not seen in the two separate systems. An important discovery during my thesis work was the formation of polymer vesicles (polymersomes), densely packed with iron oxide nanoparticles in the vesicle walls. I demonstrated that, while well-established self-assembly principles of amphiphilic block copolymers provide a valuable guideline for the preparation of nanoparticle-encapsulating block copolymer assemblies, these principles do not directly apply to the simultaneous self-assembly of nanoparticles and block copolymers. This point is especially important when it is desirable to achieve high density nanoparticle loading and specific arrangement of nanoparticles in polymer assemblies. My work described within this thesis shows how the incorporation of nanoparticles affects the self-assembly structure and how to control the morphology of nanoparticle-encapsulating polymer assemblies