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Shining a light on copper mediated living radical polymerisation : maximising end-group fidelity

The objective of this thesis was to investigate Cu(0)-mediated living radical polymerisation and explore the potential and the limitations of this system with the ultimate goal to maximise the end-group fidelity and enable the synthesis of multiblock copolymers. Careful optimisation of the ligand and catalyst concentration was shown to be vital for preservation of end-group functionality, which can be exploited for post-polymerisation modifications. High molecular weight multiblock copolymers were obtained for the first time, although the weaknesses and limitations of the technique were also revealed and discussed. At the same time, a new, novel polymerisation protocol was discovered, exploiting photo-activation in the presence of a cupric precursor CuII(Me6-Tren)Br2 and an excess of an aliphatic tertiary amine ligand Me6-Tren. For the first time under UV irradiation (λ ~ 360 nm) near-quantitative conversions and narrow dispersities for a range of targeted molecular weights were achieved while the scope of this technique was expanded to a range solvents and monomers. Significantly, temporal control is also observed during intermittent light and dark reactions and excellent end-group fidelity can be attained. This remarkable degree of control obtained during both homo and block copolymerisations motivated further investigation into the scope of the system in pursuit of acrylic multiblock copolymers with good sequential control over discrete block compositions, synthesised via a photo-mediated approach in a one-pot process without intermediate purification steps and in the absence of potentially costly additives such as photo-redox catalysts, initiators and dye sensitisers. Both techniques utilised the multiblock copolymer synthesis as a tool not only to synthesise functional well-controlled materials but more importantly to enable polymerisations with high end-group fidelity, whereby termination has been significantly suppressed.

Identiferoai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:635581
Date January 2014
CreatorsAnastasaki, Athina
PublisherUniversity of Warwick
Source SetsEthos UK
Detected LanguageEnglish
TypeElectronic Thesis or Dissertation
Sourcehttp://wrap.warwick.ac.uk/65614/

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