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    Applications of multicomponent metal-organic frameworks : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand
    (Massey University, 2021) Lee, Seok June
    Multicomponent metal-organic frameworks (MOFs) comprise multiple organic ligands that are topologically distinct. Each organic ligand is precisely positioned in a highly ordered crystal lattice. These allow tunable pore environments induced by the predictable arrangement of chemical functional groups on multiple ligands. This study was mainly focused on utilising such benefit of multicomponent MOFs. First, a novel concept for asymmetric catalysis was implemented. Sequence-specific polymer synthesis by post-synthetically linking the two ligands in a framework was then covered. Both applications exhibited new approaches that had not been demonstrated in conventional chemical reactions. This study exhibits the possibility of multicomponent MOFs as a great platform for many applications.
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    Photophysical and catalytic properties of multicomponent metal-organic frameworks : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand
    (Massey University, 2021) Cornelio, Joel
    Multicomponent metal-organic frameworks (MC-MOFs) are crystalline, porous materials built from multiple geometrically distinct organic ligands. The ligands are located in specific lattice sites in the MOF. The properties of these materials can be tuned by incorporating ligands with functional groups for a desired application. This thesis deals with studying the applications of MC-MOFs named Massey University Frameworks (MUFs) for luminescence, energy transfer, photochromism, and catalysis. Firstly, we obtain white-light emission in MC-MOFs from the combination of blue and yellow luminescence of the ligands. The trends observed in the emission spectra originate from inter-ligand energy transfer interactions. These interactions have been explored further using a variety of crystallographic and spectroscopic techniques including time-resolved luminescence at the nanosecond and picosecond timescales. In another chapter, we have studied photochromism in some MC-MOFs which is caused by light-generated organic radicals. The differences between their radical and non-radical forms has been elucidated using X-ray crystallography. We also research the impact of pore environment on the outcome of an enantioselective intramolecular aldol reaction catalysed by MC-MOFs. Finally, a number of ideas are proposed as part of future work, that take advantage of the multicomponent nature of these materials.
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    Synthesis of multicomponent metal-organic frameworks and investigations of their physical properties : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatu, New Zealand
    (Massey University, 2019) Alkaş, Adil
    Multicomponent metal-organic frameworks (MOFs) are built up from multiple ligands that are geometrically distinct. These ligands occupy specific positions in the MOF lattice. Installing different functionalities at precise locations in the framework is an important step in making MOFs for specific applications. This can be achieved by designing functionalized ligands for multicomponent MOFs. This study was, firstly, focused on design and synthesis of new linkers. The study then covered preparation of a number of quaternary MOFs. Furthermore, the study was focused on the physical and chemical properties of these MOFs, such as their catalytic activity, gas adsorption and fluorescence behaviours.
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    Interior decoration of metal-organic frameworks through a thermolabile protecting group strategy : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand
    (Massey University, 2019) Jameson, Heather
    Metal-organic frameworks are porous nanomaterials of modular construction that have shown themselves amenable to different modes of functionalization. Thermolytic deprotection (thermolysis) of incorporated thermolabile protecting groups (TPGs) has been one of these methods applied to tune the chemistry of MOFs and their material properties, accessing otherwise unattainable MOF topologies with enhanced porosity and reactive functionalities of particular interest in gas storage and separation and catalytic applications. In this thesis the TPG post-synthetic modification (PSM) technique is expanded upon in two ways. Firstly, through investigation of mono-and dual-functionalization within a flexible pillar-layer MOF family: localization of the TPG, influence on framework topology and gas sorption characteristics. Secondly, in synthesis of a set of novel ketene-protecting TPG ligands: ligand characterization, and endeavours at MOF incorporation.
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    Multicomponent metal-organic frameworks : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatu, New Zealand
    (Massey University, 2015) Liu, Lujia
    Introducing multiple functional groups into the pores of metal-organic frameworks (MOFs) promise sophisticated properties. Precise control over the position of these functional groups would enable the 3D chemical environment of discrete void spaces to be tailored. This was an outstanding challenge prior to this work. In this thesis we present a study of the synthesis, characterization and properties of MOFs that can meet this goal. These MOFs are multicomponent in nature, being built up from three geometrically distinct organic ligands. Functional groups can be appended to these ligands and are incorporated in precise locations and with perfect order in the frameworks. The chemical environment of the pores of these MOFs is “programmed” by these functional groups. MOFs constructed in this way give rise to exceptional gas adsorption characteristics, unexpected stability towards water vapour, and tunable catalytic properties.
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    The modelling of caking in bulk lactose : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Process and Environmental Technology at Massey University
    (Massey University, 1997) Bronlund, John
    Caking during storage is a serious problem for manufacturers of bulk lactose. This study was carried out to investigate the causes of caking and identify solutions as to how such problems can be eliminated. The mechanisms for caking in crystalline lactose powders were identified. Liquid bridging between adjacent particles was shown to occur in high relative humidity environments (>80% RH). These liquid bridges could form crystalline solid bridges if the material was subsequently dried out. The potential mechanism of amorphous lactose flow and bridging in conditions where the glass transition temperature is exceeded was shown to be insignificant in predominantly crystalline lactose powders (<5% amorphous lactose). The presence of amorphous lactose is still important as the amorphous matrix acts as a sink of moisture, which can be released upon crystallisation. This increases the moisture available in the system which can contribute to caking by the liquid bridging mechanism. Both of these mechanisms involve changes in the local temperature and moisture conditions within the bulk powder. Such changes were known to be caused by moisture migration under the influence of a temperature gradient. A model which describes the transport of moisture in one dimension as a result of temperature gradients was developed and validated. The microscopic scale processes of liquid bridging and amorphous lactose moisture relations were included into this model. The model predictions agreed well with experimental trials for completely crystalline lactose powders. Comparison of model predictions for the case where amorphous lactose was present on the surface of the particles showed some inadequacies exist in the model. These were the rate of amorphous lactose crystallisation and the assumption of instantaneous equilibrium between the crystallising amorphous matrix and the air present in the interstices of the bulk lactose. Using the model it was shown that for expected storage conditions, the product should be stored with a water activity below 0.57 aw if no amorphous lactose is present and below 0.25 aw if it is present. If these prescribed limits are met then the goal of producing caking free lactose powders can be achieved.