微嵌段疏水缔合聚合物/十二烷基硫酸钠溶液体系的流变特性

The Rheological Properties of Micro-Block Hydrophobically Associating Polymer/SDS Solution

研究了疏水微嵌段长度和阴离子表面活性剂十二烷基硫酸钠(SDS)对聚/表体系的流变性的影响。研究表明,微嵌段长度对疏水缔合聚合物溶液的粘性有较大影响,嵌段越长聚合物越容易发生分子间缔合其溶液粘度越大。随着SDS的加入,各聚/表体系粘度短期内出现一个极值,然后降至一个稳定值,嵌段长度越长,其极值点越大。聚合物与SDS体系表现出的剪切增稠和粘弹性特征也随嵌段长度增加而增大。通过研究不同体系平台区模量(G0)和特征松弛时间(TR)的变化规律,发现嵌段长度和SDS含量对聚/表体系物理交联缔合点的密度有较大影响,对缔合点强度影响较小。本文有助于更好地解释微嵌段疏水缔合聚合物与表面活性剂相互作用的内在因素。

In this paper,the effect of the micro-block length of the micro-block associating polymer and the concentration of the sodium dodecyl sulfate(SDS)on the rheological properties of the polymer/surfactant system was studied.The results show that micro-block length has the greater impact on the viscosity of hydrophobically associating polymer solution.The associating polymer with longer block has the larger tendency to form the intermolecular association and the higher viscosity.As the addition of SDS,the viscosity of the polymer/surfactant system reaches an extremum in short term,then loweres and keeps at a stable value.The longer the block is,the larger the extreme viscosity is.With the increasing micro-block length,the polymer/SDS system also exhibits the stronger shear thickening property and the largerviscoelastic behavior.Comparing the variation trend of the plateau modulus(G0)of solution system with the one of terminal relaxation time(TR),we found that the micro-block length and the SDS concentration all have the greater impact on the physical crosslinking density of the the polymer/surfactant system and less impact on the physical crosslinking strength.These results provide an important insight into the underlying mechanism of the interactions between surfactants and the micro-block associating polymer.