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(2024)ThesisThe design of advanced hollow fibre ultrafiltration (UF) membrane technologies for use in wastewater treatment facilities has culminated from a combination of improvements in plant operation and optimising feed water interactions. With global demands in water quality increasing, this has placed increased pressure on MBR factories to develop high strength, anti-fouling fibre modules with improved permeabilities. The fabrication of such membranes, however, is restricted by the trade-off that exists between mechanical strength and filtration properties, as well as scalability concerns that arise when transitioning from laboratory trials to field testing of prototypes. This places increased importance on the need to establish a reliable formulation plan that addresses these trade-off limitations, in addition to furthering our understanding of membrane-foulant interactions. Modifications of polymer concentration will offer deeper insight into the role that polymer phase materials have on membrane formation and high strength performance. Further variations in pore-former content will provide a route towards optimising membrane surface porosity, translating into potential improvements in fibre permeability and anti-fouling propensity. Three different experimental approaches were implemented to assess the impact of fibre composition on membrane performance. These include (1) modifying the total concentration of poly(vinylidene fluoride) (PVDF) material, (2) tailoring the composition of PVDF material with distinct molecular weights, and (3) adjusting the proportion of poly(vinyl pyrrolidone) (PVP) and poly(ethylene glycol) (PEG) pore-forming additives. Microscopy techniques were used to document any structural changes across each formulation series, whilst porometer and tensile testing instruments were utilised to provide insight into membrane permeability and strength, respectively. Membranes formulated with elevated PVDF concentrations were found to exhibit improvements in mechanical integrity at the expense of reduced clean water fluxes. This was overcome by optimizing the incorporated PVDF molecular weight, which allowed for incremental boosts in toughness without adversely affecting permeability. Testing also revealed that fibres formed with higher concentrations of pore-forming agents, most notably PEG material, were found to be more permeable. Feedwater filtration cycling was implemented to provide insight into the relative fouling behaviour of membranes formed via these three approaches. Changes in resistance were found to be primarily dictated by membrane pore size, with intermediary pore size distributions being desirable targets for balancing out the effects of short- and long-term filtration. By tracing these trends in fouling propensity back to underlying fibre compositions, this study reinforces the importance of adjusting polymer formulations for achieving high strength, anti-fouling membranes. This study also acknowledges the limitations that exist in comparing laboratory-scale filtration data of fibre samples to prototype field testing of full-scale modules. Addressing these drawbacks through an analysis of feedwater conditions used in research and industry allows us to reach an informed decision on selecting appropriate formulations in the design of innovative membrane technologies.