Counterion condensation and phase separation in solutions of hydrophobic polyelectrolytes
Counterion condensation and phase separation in solutions of hydrophobic polyelectrolytes
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DOI：
10.1021/ma001619o
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发表时间：
2001-03-13
期刊：
影响因子：
5.5
通讯作者：
Rubinstein, M
中科院分区：
文献类型：
--
作者：
Dobrynin, AV;Rubinstein, M
我们发展了疏水聚电解质溶液中的反凝聚理论。在大泽的两区模型的框架中，我们证明了项链的解决方案可以是不稳定的相分离。这种相分离是由浓度诱导的反相缩合引发的。对于在该范围内的参数，在该溶液是稳定的，我们预测的非单调依赖的链的大小对聚合物浓度。链尺寸的这种非单调性表现为在与浓缩的水溶液的交叉处溶液粘度的急剧增加。也有可能在不同的浓度制度中观察到的性质不同的物理性质的散射函数的两个峰值。在低浓度（项链）制度，在峰值位置处的散射强度随聚合物浓度增加，并在浓缩的聚合物溶液中随浓度降低。
We have developed a theory of counterion condensation in solutions of hydrophobic polyelectrolytes. In the framework of Oosawa's two-zone model we demonstrate that solutions of necklaces can be unstable with respect to phase separation. This phase separation is triggered by the concentration-induced counterion condensation. For the range of parameters at which the polyelectrolyte solution is stable, we predict nonmonotonic dependence of the chain size on polymer concentration. This nonmonotonicity in the chain size manifests itself in the dramatic increase in solution viscosity at the crossover to concentrated polyelectrolyte solution. There is also a possibility of two peaks in the scattering function of qualitatively different physical nature observed in different concentration regimes. The scattering intensity at the peak position increases with polymer concentration in low concentration (necklace) regime and decreases with concentration in concentrated polyelectrolyte solutions.