Thermogelation of methylcellulose in aqueous solutions

Aqueous solutions of methylcellulose (MC) were studied as a function of temperature. It is well known that semi-dilute MC solutions are forming a gel upon heating. The gelation phenomenon is time-dependent and reversible but with a hysteresis. Different cyclic thermal treatments were conducted characterizing the formation of progressive interactions. An aggregation above 35 degrees C is also shown by studies in dilute solution. Moreover, the role of the chemical structure (distribution of substituents and degree of substitution value) on the MC rheological properties was underlined. Gelation is then mainly attributed to hydrophobic interactions.