Multi-Phase Equilibrium in Aqueous Solutions of the Triple-Helical Polysaccharide, Schizophyllan
Multi-Phase Equilibrium in Aqueous Solutions of the Triple-Helical Polysaccharide, Schizophyllan
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三螺旋多糖裂褶多糖水溶液中的多相平衡
DOI：
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
A. Teŕamoto
中科院分区：
文献类型：
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作者：
T. Itou;A. Teŕamoto
在25°C下，使用三个不同轴比x的分级样品测定棒状多糖大叶藻多糖水溶液的三元相图：样品T-3，x=223;样品UR-28，36.8;样品U-110，18.3。研究了UR-28+T-3+水和U-110+T-3+水两个三元体系。这两种体系的相图都被一个宽的两相区占据，在该两相区中，稀的各向同性相和浓的均相在平衡时共存。U-110+T-3+水体系的相图包含两个额外的区域，一个是平衡时两个均相和一个各向同性相共存的区域，另一个是两个均相共存的区域。一个显着的分子量分馏发生在相分离，和较大的x组分几乎被排除在稀相（或相）。这些相图特征与Abe和Flory对三元非热溶液的理论预测相一致。理论和实验之间的定量一致性远不能令人满意，尽管当相互作用参数被纳入Abe-Flory理论时，这种分歧大大减少了。
Ternary phase diagrams were determined at 25°C for aqueous solutions of a rodlike polysaccharide schizophyllan, using three fractionated samples of different axial ratios x: sample T-3, x=223; sample UR-28, 36.8; sample U-110, 18.3. Two ternary systems UR-28+T-3+water and U-110+T-3+water were investigated. The phase diagram of either system was occupied by a wide biphasic region, where a dilute isotropic phase and concentrated cholesteric phase coexisted at equilibrium. The phase diagram of the system U-110+T-3+water contained two additional regions, one where two cholesteric phases and one isotropic phase coexisted at equilibrium and the other where two cholesteric phases coexisted. A remarkable molecular weight fractionation took place on phase separation, and the larger x component was almost excluded from the dilute phase (or phases). All these features of the phase diagrams were consistent with the theoretical prediction by Abe and Flory for athermal ternary solutions. Quantitative agreement between theory and experiment was far from satisfactory, although the disagreement was considerably diminished when the interaction parameter was incorporated into the Abe–Flory theory.