Benzylidenepolyhydric Alcohol類の膠質化学的研究 (第7報)

Abstract

Benzylidene-d-sorbitol undergoes gelation when dissolved in various solvents with warming and the solution allowed to cool. The state of gelation is the same as in the case of high-molecular gel-forming substances like gelatin but the viscosity of this solution differs from that of gelatin solution, not showing polymer-like properties but those agreeing with Einstein's viscosity formula. From such a fact, the state of gelation of benzylidene-d-sorbitol solution is similar to polymer-like gel-forming substances like gelatin but does not behave like a polymer from the point of viscosity. The solution before gelation has viscosity no different from that of ordinary solutions but an abnormal viscosity occurs at around the gelation point, and this is assumed to be due to a change in the structure inside the solution during gelation. From such a change in viscosity, relationship between the gelation phenomenon of a solution and coagulation of a gelation agent was examined by measuring dielectric constant of the solution. Increase of dielectric constant decreases with increasing concentration at around the gelation point and this suggested that there is a connection between polarity of benzylidene-d-sorbitol and gelation.