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Analytical Electron Microscopy reveals the possible existence of ceramic particulates as the active surface of fractal membranes, obtained from deposition of a colloidal suspension of inorganic-organic materials on polypropylene hollow fibres. These membranes exhibit high ultrafiltration flux with no obvious fouling. Ultrafiltration flux of skim natural rubber latex, at a specified concentration, was maintained constant for a period of at least 2 hours. On the contrary, the flux of unfractalized polypropylene hollow fibres dropped drastically within 40 minutes with severe irreversible fouling. Familiar characteristic curves of flux proportional to pressure gradient in the low pressure region, followed by a transition zone and a region of pressure independent flux, were also observed for the case of fractal membranes, but with In the non gel polarized region, flux a more pronounced effect of shear rate. was found proportional to shear rate to the power of 0.88, which is somewhat higher than that expected by the Blatt equation. As expected, solute concentration affected the flux in accordance with the gel polarized model whereby flux is a linear function of the retained solute concentration. Flux was also found to increase by 1.9% for every degree centigrade increment in the This is lower than the theoretical temperature range of 30° to 65OC. expectation based on the viscosity changes, which indicates some degree of solute-solvent interaction.