GELATION OF XANTHAN BY TRIVALENT CHROMIC IONS MONITORED BY H-1-NMR RELAXATION - A PRELIMINARY-STUDY

Gel formation of xanthan by trivalent chromic ions is investigated within the H-1 NMR relaxation time framework. To our knowledge such an approach has not previously been discussed in the literature, and we found it appropriate to consider this method in some detail. In particular, this NMR technique seems to provide significant information regarding the kinetics of polymer-chromium ion gel formation during the induction period. Moreover, the work presented in this paper suggests that NMR and dynamic mechanical analyses (using oscillatory rheological testing) produce complementary information with respect to such processes.