壳聚糖浓溶液流变性质研究──零剪切粘度的测定和外推

用落球法测定了不同溶剂体系和浓度的壳聚糖浓溶液的零剪切粘度η０，用ＲＰＸ－７０５多功能流变仪同轴圆筒方法测定了各浓溶液的粘度随剪切速率的变化关系，并用Ｐｅｒｒｒ、Ｃｒｏｓｓ和Ｂａｌｌａｕｆｆ方法进行了求η０的外推．将外推结果与落球法结果进行了比较，认为Ｃｒｏｓｓ方法的结果与实际测得结果更接近，可以代替落球法，这样可以简单地得到壳聚糖浓溶液η０的信息．

RHEOLOGICAL PROPERTIES FOR CONCENTRATED SOLUTION OF CHITOSAN ZERO SHEAR VISCOSITIES

Flow properties for concentrated solution of chitosan were described in 50%HCOOH,50%CH3COOH, 0.2mol/l HCl and 0.1mol/l CH3COOH+0.1mol/l CH3COONa under the concentration from 2 to 5g/100ml solvent. Flow equations presented in literature,such as Ferry equation,Cross equation and Ballauff equation,were tested from the point of view of the extrapolating method for evaluating the zero shear viscosities.The results of extrapolation were compared with the values measured by falling-ball method. It was shown that the method based on Cross equation gave relatively good results.