弛豫法研究预交联颗粒凝胶的界面扩张流变性质

采用界面张力弛豫方法研究了一种新型聚合物——预交联颗粒凝胶(PPG)的界面流变性质,考察了电解质及传统直链聚丙烯酰胺与PPG的相互作用对体系界面性质的影响,计算得到了各体系界面扩张弹性和黏性的全频谱,并通过归一法计算得到了相应的Cole-Cole图.结果表明,随着体相浓度的增加,PPG在界面层中形成网络结构,界面扩张弹性和黏性大幅增强.电解质能够中和PPG结构中的电荷,明显降低扩张弹性和黏性.直链聚丙烯酰胺与PPG在界面上可能形成更为复杂的结构,膜的黏弹性由PPG决定.

Dilational Rheology Properties of Branch-performed Particle Gel by Relaxation Measurements

The interfacial dilational rheological properties of a novel polyacrylamide derivative, branch-preformed particle gel(PPG), were studied by interfacial tension relaxation measurements. The effects of electrolytes and conventional polyacrylamide on dilational rheological properties of PPG were studied. The dilational elasticity and viscosity components of different systems were calculated by Fourier transform and displayed as Cole-Cole curves. The results show that interfacial elasticity and viscosity components of PPG solutions both increase due to the formation of interfacial net structure with the increasing bulk concentration. Electrolyte will neutralize the excess charge of PPG, thus decreases dilational elasticity and viscosity. When mixed with liner polyacrylamide, the more complex structure is formed, but the overall viscoelasticity of the system is still determined by PPG.