Application of Image Processor Technics to the Study of Viscoelastic Properties of Polysaccharide Aqueous Solutions

Three types of Gellan Gum aqueous solutions were studied，in which Ca^&lt；2+&gt；-contents were controlled to(I)&lt；&lt；0.01 wt%and(Ii)*0.5 wt%，and the replacement of Na^+toK^+was performed by ion-exchange resin.In the case of(I)，abrupt decreasings in viscosity in the temperature range of&lt；plus-minus&gt；0.5°C C were observed，and we assumed that this may cused by the temperature range of&lt；2+&gt；-contents were observed，and we assumed that this may cused in the temperature range of&lt；2+&gt；In the case of K-type Gellan Gum，viscosity of solutions decrease as the temperature was raised，through the maximum point of viscosity。Hyaluronic acid aqueous solutions，of which two types of molecular weight，1.0*10^6 and 2.0*10^6 and four kinds of concentration of 1.0，0.75，0.5 and 0.25 wt%were studied in the period of 360-23，040s。J_1(Omega Lambda)，J_2(Omega Lambda)-In(Omega Lambda)plot of these solutions were nearly expressed by Voigt model，here J^*(Complex Compliance)=J_1-i·J_2in the whole concentration range。In the case of Cole-Cole plot(J^*=alpha[1/{1+(Iomega Lambda)beta}]，all observed points could be expressed as an arc with beta=0.725.This means that distribution of retardation time should be taken into consideration of viscoelastic behaviors of Hyaluronic acid aqueous solutions.

Three types of Gellan Gum aqueous solutions were studied, in which Ca^<2+>-contents were controlled to (i) <<0.01wt% and (ii)*0.5wt%, and the replacement of Na^+ toK^+was performed by ion-exchange resin.In the case of (i), abrupt decreasings in viscosity in the temperature range of <plus-minus>0.5ﾟC were observed, and we assumed that this may be caused by Helix-Coil transition of Gellan Gum molecules. In the case of K-type Gellan Gum, viscosity of solutions decrease as the temperature was raised, through the maximum point of viscosity. Hyaluronic acid aqueous solutions, of which two types of molecular weight, 1.0*10^6 and 2.0*10^6 and four kinds of concentration of 1.0,0.75,0.5 and 0.25 wt% were studied in the period of 360-23,040s. J_1 (omega lambda), J_2 (omega lambda)-In (omega lambda) plot of these solutions were nearly expressed by Voigt model, here J^*(complex compliance) =J_1-i・J_2 in the whole concentration range. In the case of Cole-Cole plot (J^*=alpha[1/{1+(iomega lambda)beta}], all observed points could be expressed as an arc with beta=0.725.This means that distribution of retardation time should be taken into consideration of viscoelastic behaviors of Hyaluronic acid aqueous solutions.