Gelation Studies, 3

Abstract

Abstract Summary: The sol‐gel transition of one thermoreversible gelling mixture made of xanthan gum and locust bean gum has been studied by using in situ time‐resolved dynamic light scattering (DLS) and measuring the spin‐lattice relaxation time T 1 of several protons. A critical dynamical behavior was observed near the sol‐gel transition, which is characterized by the presence of power‐law spectra over four decades of the delay time in the time‐intensity correlation function g 2 ( t )−1 ∼ t −μ at 48 °C. The increase in T 1 with increasing temperature becomes steeper at 50 °C indicating a significant change in the local mobility of one anomeric proton of the xanthan side chain and the anomeric protons of the locust bean gum mannose backbone. Temperature dependence of the spin‐lattice relaxation time T 1 for the equatorial anomeric proton of the mannopyranosic unit located next to the main chain of the xanthan. image Temperature dependence of the spin‐lattice relaxation time T 1 for the equatorial anomeric proton of the mannopyranosic unit located next to the main chain of the xanthan.