Microstructure and swelling behavior of ion-exchange resin

✍ Scribed by Fumiyoshi Ikkai; Mitsuhiro Shibayama

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 703 KB
• Volume: 34
• Category: Article
• ISSN: 0887-6266
• DOI: 10.1002/(sici)1099-0488(19960715)34:9<1637::aid-polb13>3.0.co;2-8

✦ Synopsis

The microstructure and swelling kinetics of ion-exchange resins having sulfonic acid groups were investigated by small-angle neutron scattering (SANS) and swelling experiments as functions of the crosslinking density (CD), pH, and the salt concentration (C&. The swelling kinetics was analyzed on the basis of the Tanaka-Fillmore swelling equation for the cooperative diffusion of polymer gels. The swelling behavior was very sensitive to CD, but not to pH and Csalt. The SANS intensity functions, Z(q), were independent of CD and well described with a power law function, Z(q)q-D, where q and D are the magnitude of the scattering vector and the mass-fractal dimension, respectively. D was estimated to be -2, indicating that the resin consisted of a rather coarsely interconnected domains irrespective of CD at swelling equilibrium. It was found that CD is the most important parameter determining the swelling power of ion-exchange resin. However, no remarkable variations were found in the microstructure in the order of tens to hundreds of angstrom. 0 1996