NMR-STUDY OF THE DIFFUSION-PROCESSES IN GELS

Stimulated spin-echo and Carr-Purcell pulse sequences, with pulsed mag netic field gradients, have been used to study the self-diffusion proc esses of the water in swollen and in supercoiled polyacrylamide gels a nd in polysaccharides agarose gels, for different polymer concentratio ns, Restricted diffusion effects are evidenced in both types of gels t hrough the time dependence of the diffusion constant, The results can be interpreted in the framework of diffusion model through permeable w alls. Copyright (C) 1996 Elsevier Science Inc.