450d Liquid Crystalline Gel Induced by Ionic Flow

Toshiaki Dobashi1, Takao Yamamoto2, and Masahiro Nobe1. (1) Biological and Chemical Engineering, Gunma University, 1-5-1, Tenjin-cho, Kiryu, 376-8515, Japan, (2) Physics, Gunma University, 1-5-1, Tenjin-cho, Kiryu, 376-8515, Japan

Curdlan dissolved in aqueous sodium hydroxide was dialyzed to aqueous calcium chloride to form a gel. Transparent and turbid concentric layers observed in the gel cross section perpendicular to the long axis of the dialysis tube were identified as liquid crystalline gels with refractive index gradient and amorphous gels, respectively. The gelation proceeded in proportion to the root of time. The unique pattern formation was attributed to a nanoscale structure change of curdlan aggregates and calcium-induced cross-linking resulting from a diffusion of calcium cations and hydroxide anions through the dialysis tube. It is suggested that the orderedness of the curdlan molecules decreases by the increase of the curvature of the concentric liquid crystal layers as the layer comes toward the center of the dialysis tube due to a restriction of geometrical condition.