Preparation and properties of cationic membranes obtained by radiation grafting of methacrylic acid onto PTFE films
Article first published online: 9 MAR 2003
Copyright © 1989 John Wiley & Sons, Inc.
Journal of Applied Polymer Science
Volume 38, Issue 7, pages 1229–1242, 5 October 1989
How to Cite
Hegazy, E.-S. A., Taher, N. H. and Kamal, H. (1989), Preparation and properties of cationic membranes obtained by radiation grafting of methacrylic acid onto PTFE films. J. Appl. Polym. Sci., 38: 1229–1242. doi: 10.1002/app.1989.070380704
- Issue published online: 9 MAR 2003
- Article first published online: 9 MAR 2003
- Manuscript Accepted: 11 MAY 1988
- Manuscript Received: 9 MAY 1988
Cationic membranes were prepared by direct radiation grafting of methacrylic acid (MAA) onto poly(tetrafluoroethylene) (PTFE) films followed by alkaline treatment to confer ionic character in the graft copolymer. The complete inhibition of homopolymerization of MAA by using ammonium ferreous sulfate (Mohr's salt) failed. However, the addition of 0.5 wt % FeCl3 to the monomer solution effectively inhibited the homopolymerization process and higher grafting yield was obtained. It was found that the graft polymerization proceeded successfully in presence of methanol/water mixture (30/70 wt %), and much higher degrees of grafting were obtained as compared with those in the presence of other diluents used here. The influence of irradiation atmosphere (air, N2 gas, and vacuum) on the grafting process was investigated. The dependence of the grafting rate on MAA concentration was found to be of orders 2.9 and 0.72 in the presence of 0.5 wt % Mohr's salt or 0.5 wt % FeCl3, respectively. This grafting system proceeds by the front mechanism. Investigation of mechanical properties, electrical conductivity, and swelling behavior of the grafted films revealed that such a copolymer could be acceptable in practical use as a cation-exchange membrane.