Nasef, Mohamed Mahmoud and Saidi, Hamdani (2004) XPS surface analysis of radiation grafted membranes. In: Regional Symposium on Membrane Science and Technology 2004, 21-25 April 2004, Puteri Pan Pacific Hotel, Johor Bahru, Johor, Malaysia.
The surfaces of sulfonic acid membranes prepared by radiation-induced graft copolymerization of styrene onto poly(tetrafluoroethylene) (PTFE) followed by sulfonation reactions were characterized by x-ray photoelectron spectroscopy (XPS). Changes in the atomic concentrations of the characteristic elements are investigated with the purpose of monitoring of the chemical structure of the membranes surfaces and their impact on some important electrochemical properties. The results of XPS spectral analysis shows that PTFE matrix undergo remarkable changes in terms of chemical compositions and binding energies of their basic elemental components with the variation of the degree of grafting. The atomic ratio C/F was found to increase drastically in the membranes with the increase in the degree of grafting. The membranes were found to have almost pure hydrocarbon structure at the layers closed to their surfaces with inhomogeneous sulfur distribution indicating the presence of segregation in the membrane structure and the presence of two separated microdomains. The results of these investigations suggest that the morphology of the surface is going to play an important role in the affecting the stability of these membranes when they are used in electrochemical applications. Moreover, XPS is an effective technique to study the surface properties of radiation grafted membranes.
|Item Type:||Conference or Workshop Item (Paper)|
|Uncontrolled Keywords:||Carbon/fluorine ratio, chemical stability, radiation grafted sulfonic acid membranes, surface chemical analysis, XPS|
|Subjects:||T Technology > T Technology (General)|
|Divisions:||Chemical and Natural Resources Engineering (Formerly known)|
|Deposited By:||Norhani Jusoh|
|Deposited On:||02 Sep 2008 07:13|
|Last Modified:||01 Jun 2010 15:41|
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