SPATIAL INFORMATION ON A POLYMER GEL AS STUDIED BY H-1-NMR IMAGING - 4 - SHRINKAGE BY THE APPLICATION OF AN ALTERNATING ELECTRIC-FIELD TO APOLYMER GEL

We have measured the spatial distribution of H-1 spin density and H-1 spin-spin relaxation timer T-2, of water molecules in a crosslinked po ly(methacrylic acid) (PMAA) gel under an alternating current (AC) elec tric field by means of proton nuclear magnetic resonance imaging. The experimental results show that a cylindrical gel shrinks to a cylindri cal shape at long elapsed time after the application of an AC electric field, and that the H-1 spin densities on both electrode sides of the gel are high and the mobilities are low. The translational behavior o f water molecules in the gel during shrinkage processes under an AC el ectric field is discussed at the molecular level. (C) 1998 Elsevier Sc ience Ltd. All rights reserved.