部分水解聚丙烯酰胺水溶液的零剪切黏度和临界浓度

通过蠕变和振荡实验分别测定了部分水解聚丙烯酰胺(PHPA)水溶液的零剪切黏度(η₀)和线性黏弹区储能模量(G'), 并依据其浓度依赖性得到叠加浓度(C^*)和交叠浓度(C^*), 考察了温度、pH值和电解质(NaCl和CaCl₂)浓度的影响. 结果表明, 随着温度的升高和电解质浓度的增大, PHPA水溶液的η₀及G'减小, C^*和C^*增大; 电解质阳离子价态越高, 溶液黏度和临界浓度的变化越显著; 而随着pH值的增大, η₀及G'先增大后减小, C^*和C^*先减小后增大.

Zero-shear Viscosity and Critical Concentrations of Aqueous Solution of Partially Hydrolyzed Polyacrylamide

Creep and oscillation experiments were performed to measure the zero-shear viscosity(η0) and storage modulus(G′) of aqueous solution of partially hydrolyzed polyacrylamide(PHPA),respectively.The overlapping concentration(C*) and crossover concentration(C**) of PHPA solution were determined through the dependence of η0on solution concentration(C).Effects of temperature,pH value and electrolytes(NaCl and CaCl2) on C* and C** were investigated.The results show that as temperature and electrolyte concentration are raised,η0and G′ decrease while C* and C** increase gradually.The higher the electrolyte cation valence is,the more obvious the induced variation of viscosity and critical concentrations of PHPA solution is.With pH value increasing,η0and G′ increase initially and decrease subsequently while C* and C** decrease first and increase afterwards.