羧甲基瓜儿胶与带相反电荷表面活性剂复合体系溶液的流变行为

Rheology of Anionic Carboxymethyl Guar Solution in the Presence of the Opposite Charged Surfactant

测定了在十六烷基三甲基溴化铵(CTAB)存在条件下羧甲基瓜儿胶溶液的流变行为,发现随着CTAB浓度的增加,羧甲基瓜儿胶溶液的黏度可以增加到两个数量级以上,表现出类似凝胶的性质;随着pH值的增加,溶液的零切黏度先上升后下降。以上的实验结果表明,表面活性剂之间的疏水相互作用以及高分子链电荷密度对溶液的流变行为有着非常显著的影响,疏水相互作用的增强有利于提高具有交联作用的聚集体的弛豫时间,而高分子链电荷密度的增加将有利于聚集体的形成。如果表面活性剂被诱导在水相中形成胶束,则表面活性剂对聚电解质溶液流变行为的影响将迅速下降。

The rheology of anionic carboxymethyl guar （ CMG ） solution in the presence of cetyltrimethylammonium bromide （CTAB） was measured. It is found that the viscosity of CMG solution increases more than two orders in magnitude and the gel-like behavior of CMG solution in the presence of CTAB was observed. In particular, the zero shear viscosity of solution increases and then decreases with the pH value increasing. The experimental results indicate that the effect of hydrophobic interaction between the surfactants and the charge density of polymer chains upon the aggregation of polymer and surfactants is significant. The intensity of the hydrophobic interaction is beneficial to increase the relaxation time of the polymer-associate aggregates which associate polymer together like the cross-linkers. On the other hand, the increasing of the charge density is beneficial to the formation of the polymer-associate aggregates. On the occasion that the surfactants have been induced to form free micelles in solution, the effect of surfactants upon the rheology of polymer solution drops swiftly.