Khodabandeh_whole_thesis.pdf (15.94 MB)
Polymer nanoparticles and their supracolloidal monolithic structures for applications in separation science
thesisposted on 2023-05-27, 12:08 authored by Khodabandeh, A
Porous polymers generated from high internal phase emulsions (HIPEs), having interconnected open-void morphology, low density and high porosity up to 95%, are finding various applications including separation science due to their exceptional properties, such as tunable pore size and surface characters. A new class of polyHIPE materials has been prepared using HIPE template stabilized by a series of tailor-made polymeric surfactant as sole stabilizer. These polymeric surfactants were synthesized by radical addition-fragmentation chain transfer (RAFT) polymerization, which from the obtained copolymer is called an amphiphilic macro-RAFT agent. The first section focuses on the preparation and characterization of functionalized polyHIPE materials prepared via HIPE-template stabilized by an anionic polymeric surfactant. The presence of these amphiphilic species allowed the successful preparation of a polyHIPE upon polymerization. The effect of concentration of macro-RAFT agent, pH, initiator, hexadecane as an organic modifier and the polymerization temperature on the morphology of the resulting porous materials was investigated. A strategy for preparation of functional polyHIPEs and a tool to transfer the RAFT moiety to the surface by introducing macro-RAFT agent was established. Upon development of various new polyHIPE materials, an inverse high internal phase emulsion was introduced to a capillary format as a 'column housing'. The influence of the PEO-based brush-type amphiphilic macro-RAFT agents on the morphology and surface chemistry of the resulting macroporous polymers is discussed in detail. Using nano-liquid chromatography, it is shown that the polyHIPE are decorated with different microenvironments amongst the voids or domains of the monolithic structure. This is the first reported use of a hydrophilic polyHIPE in a capillary format as a stationary phase and also the first demonstration of the role of the RAFT group of the emulsifier in the attachment of the obtained polyHIPE to the inner surface of a capillary format column. Furthermore, polyHIPE materials have also been prepared by using water in oil template using macro-RAFT agent as polymeric surfactant, while the RAFT part of the macro-RAFT agent is placed in the oil phase (monomer phase). The obtained polyHIPE is a tough material with a close structure. The pore structure of polyHIPEs was closed. Further study shows that by removing the RAFT-end group of the polymeric surfactant, the obtained polyHIPE possess an open structure with voids. The effect of the RAFT part of the polymeric surfactant on the surface chemistry of the polyHIPE is discussed. Novel technology was developed to allow straightforward functionalization of the obtained polyHIPE via surfactant-assisted functionalization strategy for application in separation science as a new functionalized stationary phase.
Rights statementCopyright 2016 the author Chapter 2 appears to be, in part, the equivalent of a pre- or post-print version of an article published as: Khodabandeh, A., Dario Arrua, R., Desire, C. T., Rodemann, T., Bon, S. A. F., Thickett, S. C., Hilder, E. F., 2016. Preparation of inverse polymerized high internal phase emulsions using an amphiphilic macro-RAFT agent as sole stabilizer, Polymer chemistry, 7(9), 1803-1812. Further re-use and further distribution is not permitted without express permission of the publisher. Chapter 3 appears to be the equivalent of a post-print version of an article published as: Khodabandeh, A., Dario Arrua, R., Mansour, F. R., Thickett S. C., Hilder, E. F., 2017. PEO-based brush-type amphiphilic macro-RAFT agents and their assembled polyHIPE monolithic structures for applications in separation science. Nature - Scientific reports, 7, 7847. The article was . licensed under Creative Commons Attribution 4.0 International (CC BY 4.0) https://creativecommons.org/licenses/by/4.0/ Chapter 4 appears to be, in part, the equivalent of a pre- or post-print version of an article published as: Khodabandeh, A., Dario Arrua, R., Coad, B. R., Rodemann, T., Ohigashi, T., Kosugi, N., Thickett S. C., Hilder, E. F., 2018. Morphology control in polymerised high internal phase emulsion templated via macro-RAFT agent composition: visualizing surface chemistry, Polymer chemistry, 9(2), 213-220. Further re-use and further distribution is not permitted without express permission of the publisher.