الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
from the present work the following conclusions have been arrived at:
* It was possible to prepare novel ion exchange membranes with characteristics that are comparable to many reported in the literature.
* The type of cellulose ester affected the membrane characteristics.
* Deacylated cellulose ester proved to be a suitable polymer matrix by which heterogeneous ion exchange membranes could be fabricated.
* Membranes before deacylation had inferior properties than after deacylation.
* Deacylation gave thinner membranes than before deacylation.
* Acceptable percent permselectivities and ion exchange capacities were obtained from the fabricated membranes.
* Tensile and burst strengths varied directly with percent elongation.
* Deacylated CAB resulted in the highest burst and tensile strengths and a low
percent elongation, followed by CA(P) and CA(S). » The presence of different types of ion exchange resins within the membrane
matrix affected the different characteristics of the membranes notably.
* The addition of the ion exchange resins to the polymeric materials generally resulted in relatively thicker membranes compared to those containing no resin.
* Membrane thickness depended upon the particle size of the existing ion exchange resin, since the whole resins gave thicker membranes than the ground ion exchange resins.
* Membranes formed from CA(P) were thinner and stronger than those made from CA(S).
* The percent swelling capacity of the ion exchange membranes were lower than the resin-free membranes.
* The type of ion exchange resin (non-ionic, cationic and anionic) did not have a significant effect on the percent swelling capacity for the different membranes.
* The type of ion exchange resin and its particle size had a marked effect on the percent permselectivity, as its value was appreciably increased (3 : 4 fold) by the addition of the ion exchange resins to the membrane matrix..
* The non-ionic resin XAD16 had a relatively high permselectivity with CA(S), intermediate value with CA(P) and lowest value with CAB.
* The cationic resin 252Na had slightly high values of permselectivity with the CA(P) for both mass ratios tried, followed by CA(S) while the least was CAB.
* The anionic resin resulted in permselectivities in the order CA(S) > CA(p)> CAB.
* The ion exchange capacity of the ion exchange membranes was appreciably higher than the resin-free membranes.
* The non-ionic resin XAD16 caused the highest value of ion exchange capacity followed by the cationic resin 252Na followed by the anionic resin 900C1.
* The anionic resin was more prone to fouling than the cationic resin, while the non-ionic one was the least prone to fouling.
* The presence of ion exchange resins within the membrane matrix reduced the burst and tensile strengths of the prepared ion exchange membranes.
* Ground ion exchange resins produced ion exchange membranes with higher burst strength than unground resins.
* The type of polymeric material had a clear effect on the tensile strength of the resulting ion exchange membranes, while the type of ion exchange resin does not have a significant effect on the values of tensile strength.