水溶性聚酯浓溶液的流变特性

SHEAR-THICKENING FEATURE OF CONCENTRATED AQUEOUS SOLUTIONS OF WATER-SOLUBLE POLYESTERS

研究了由对苯二甲酸二甲酯、间苯二甲酸、间苯二甲酸二甲酯 5 磺酸钠与乙二醇等共缩聚合成的PET型水溶性聚酯浓水溶液 (质量浓度 3 0 % )的流变特性 .研究表明 ,溶液的表观粘度随切变速率的变化规律呈现一定的切力增稠特征 ,流动指数范围为 1 0 4～ 1 2 0之间 ;其lgηa τ曲线呈线性 ,零切粘度值为 1 5 8～3 5 2cP ,随分子量、分子结构和温度而异 ,其中分子链中间苯二甲酸乙二醇酯 5 磺酸钠链节含量对溶液粘度影响较大 ;粘流活化能因分子结构和切变速率而变 ,其值范围为 1 2 0～ 2 3 9kJ/mol.

The rheological properties of concentrated aqueous solutions of water\|soluble polyesters prepared by copolycondesation of dimethyl terephthalate,iso\|phthalic acid,dimethyl 5\|sodiosulfoisophthalate with ethylene glycol,have been investigated.The concentrated aqueous solutions (30%) of water\|soluble polyesters show a weak shear\|thickening feature with flow index from 1.04 to 1.20.Their lg η a\| τ curves show a linear feature,and the zero shear viscosity varies with molecular structure,molecular weight and temperature.Specially,the content of bis(2\|hydroxyethyl)5\|sodiosulfoisophthalate in molecular chains has a large effect on the viscosity of solutions.Their viscosity\|flow activation energy varies with molecular structure of the polymer and the shear rate in a range of 12.0\|23.9kJ/mol.