Complex Polymer Architectures via Controlled Polymerisation Techniques

PhD ThesisThe rise of controlled polymerisation techniques opens avenues toward sophisticated polymeric architectures ranging from multiblock-, star-, cyclic- to graft polymers. The advent of click chemistry combined with the excellent definition of contempo-rary macromolecules further expand the toolbox of polymer chemists. However, joining monomers with very contrast properties remains a crucial challenge to enable the synthesis of functional macromolecules. Obtaining amphiphilic macromolecules with a segmented structure is of great interest due to the promising properties that result from the polymer composition such as tuneable self-assembly in bulk and solu-tion. Especially, multi-block copolymers offer a plethora of exciting properties, easi-ly tuned by modulating parameters such as monomer composition, block length, block number and dispersity. In this thesis, copper-mediated reversible-deactivation radical polymerisation (Cu-RDRP) is demonstrated to be compatible with thiol-bromo post-polymerisation modification in a one pot reaction setup. The obtained high molecular weight amphiphiles are demonstrated to act as friction modifiers when blended in commercial engine base oils. The acquired expertise is further ap-plied for the synthesis of hybrid graft polymers from 2-oxazolines and acryla-mides/acrylates. Due to their remarkable properties, 2-oxazolines are evolving to become a key player in the fields of biology, chemistry and engineering. In this the-sis, the synthesis of well defined brush polymer architectures is demonstrated via an inimer compound that has both an initiating group for Cu-mediated RDRP and a 2-oxazoline ring for cationic ring opening polymerisation. Thus, various combinations of poly(2-oxazoline-brush-acrylate/acrylamide) copolymers were obtained by graft-ing from a poly(2-oxazoline) backbone. By varying the hydrophilic/hydrophobic ratio of the acrylate brushes, oil soluble brush polymers were synthesised and their friction modifying behaviour was tested. The versatility of this synthetic method is emphasised by the successful incorporation of sugar-containing acrylamides. This variation allowed the synthesis of smart bioactive macromolecules with ther-moresponsive segments. The investigation of solution behaviour, drug encapsulation and protein interaction are carried out, yielding promising results for potential bio-medical applications