水解度对疏水缔合聚丙烯酰胺溶液性质的影响

Influence of Hydrolysis Degree on Properties of Associating Polymers Solution

陈洪陆卫婷叶仲斌韩利娟罗平亚

CHEN Hong LU Wei-Ting YE Zhong-Bin HAN Li-Juan LUO Ping-Ya

以丙烯酰胺、丙烯酸钠及疏水单体共聚合成了水解度为25％的疏水缔合聚丙烯酰胺（HAPAM），采用加强碱在95℃高温下水解的方法，分别获得水解度50％和70％的聚合物，并研究三种不同水解度下HAPAM溶液的性能。实验结果表明：HAPAM水溶液的表观黏度随水解度的增大先增大后降低；不同水解度的HAPAM溶液表现出了一定程度的盐增黏现象，水解度为50％和70％的HAPAM盐溶液随着Ca2＋、Mg2＋浓度的增加出现相分离；不同水解度HAPAM溶液黏度随剪切速率的增加而降低，表现出明显的剪切稀释性；水解度低的聚合物溶液随聚合物浓度的增加更易表现出黏弹性，而水解度过高时，溶液只能表现出黏性行为；同一水解度的聚合物，随着NaCl浓度的增大，溶液的黏弹性呈现先增大后降低的趋势。图15参15

A hydrophobically associating polyacrylamide(HAPAM) with a certain hydrolysis degree(25%) had been synthesized by copolymerization of acrylamide,sodium acrylate and hydrophobic monomer.The higher hydrolysis degrees of polymer were obtained through hydrolysis reaction by sodium hydroxide under high temperature of 95℃.The effects of the hydrolysis degree,salinity,and shear rate on the viscosity of hydrophobically associating polymer were investigated in aqueous solution.The experiment results showed that the apparent viscosity of the polymer solution increased first and then decreased with increasing hydrolysis degree.It was observed that the viscosity was greatly affected by the salt concentration and obvious phase separation occured in the polymer solution when the hydrolysis degree was higher than 50% at high Ca2+ and Mg2+ concentration.Under the experimental shear rate,the viscosity behaviors of HAPAM showed shear thinning.The polymer solution exhibited remarkable viscoelasticity at lower hydrolysis degree,however,the polymer solution only appeared viscosity when the hydrolysis degree exceeds to a certain extent.For the same polymer,there was a maximum of the viscoelasticity of the solution with the increasing of the NaCl concentration.