ALGINATE POLYELECTROLYTE IONOTROPIC GELS .9. DIFFUSION CONTROL EFFECTS ON THE RELAXATION-TIME OF SOL-GEL TRANSFORMATION FOR TRANSITION-DIVALENT METAL ALGINATE IONOTROPIC GEL COMPLEXES

The rate of gel growth for spherical ionotropic metal alginate gel complexes has been measured. The experimental results show that the stability of these complexes increases in the order Mn < Co < Ni < Zn < Cu alginates. The factors which affect the relaxation time, such as the radius of the interdiffusing metal ion, the density and the pH of the electrolyte solution, as well as the concentration of the alginate sol have been examined. A mechanism consistent with the experimental results has been discussed.