Quasi-Equilibrium Gelation Temperature of Aqueous Methylcellulose

抄録

Aqueous methylcellulose (MC) forms hydrogel upon heating and the gel dissolves upon cooling i.e. thermo-reversible gelation. However, the values of the gelation temperature differ depending on the sources of MC samples and on the methods of determination as well. In this study, we have obtained a lower limit of the gelation temperature for a specific MC below which aqueous MC does not form the gel, by dually extrapolating the holding time for gelation to infinite and the mechanical probing force to zero. The gelation temperature obtained in this manner decreased with increasing concentration of the MC; to cite a case, it was located at ca. 21 ̊C for 10 wt%, which is ca. 10 ̊C lower than a conditional value estimated after holding 1 h without these dual extrapolations.