الفهرس 
theoreticalOnly 14 pages are availabe for public view
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Abstract
In the present work, an attempt to prepare cellulose-based membranes which might be suitable for dialysis in general and blood dialysis in particular, has been made. Membranes currently used for dialysis of blood by the artificial kidney are in the majority of cases regenerated celluloses, such as cuprophane, which is regenerated from cuprammonium hydroxide solution, as well as hydrolyzed cellulose acetate membranes which represent another class of cellulose-based dialysis membranes. In general cellulosic membranes are preferred to synthetic ones for numerous reasons including increased hydrophilicity and biocompatibility. In the present investigation novel deacetylated cellulose acetate membranes were fabricated and tested for their permeability (expressed by the half times of dialysis, the overall mass transfer coefficient, and diffusivities) to sodium chloride in aqueous solution by closed loop dialysis. Numerous variables were studied for their effect on membrane permeability to NaCl, and these were: type of solvent mixture used in dissolving the cellilose acetate and its composition(casting solution composition); deacetylation bath composition ; deacetylation bath temperature ; coagulation bath composition ; membrane wet thickness; casting duration time ;time between casting and coagulation ; polymer concentration in casting solution; and initial solution concentration . It was found that each of these factors had a profound effect on the permeability of sodium chloride, and that therefore an optimum membrane could be fabricated through application of the optimum values of each factor arrived at in fabricating any single membrane