Phase Separation Kinetics of Polyelectrolyte Solutions

带电大分子水溶液的热力学稳定性对所有生命形式都至关重要。聚电解质溶液在水中表现出复杂的行为，提出了许多智力挑战。我们建议使用光散射和中子散射进行实验，并进行互补的理论计算，以便对聚电解质溶液中的相分离动力学有一个基本的了解。提出的研究的具体实验系统是含有已知量的氯化钡的聚苯乙烯磺酸钠水溶液。我们正在进行的关于这一主题的研究表明，我们对带电大分子如何进行相分离的基本理解取得了突破。基于有限的初步数据，发现相似带电聚合物链的聚类在新稳定相成核的原始阶段起中介作用。提出的研究将建立这一新发现现象的有效性和普遍适用性。拟议的研究将对疾病控制的医学研究以及包括食品、化妆品、个人护理产品和制药在内的一些关键行业产生影响。此外，聚电解质正在成为最重要的材料，但人们对其了解最少。在这一重要研究领域培养研究生是拟议活动的重要教育组成部分。

Thermodynamic stability of aqueous solutions of charged macromolecules is of central importance in all forms of life. Polyelectrolyte solutions in water exhibit complex behavior and present many intellectual challenges. We propose to perform experiments using light scattering and neutron scattering, and to carry out complementary theoretical calculations, pertinent to a fundamental understanding of the kinetics of phase separation in polyelectrolyte solutions. The specific experimental system of the proposed research is aqueous solutions of sodium polystyrene sulfonate containing known amounts of barium chloride. Our ongoing research on this subject points towards a breakthrough in our fundamental understanding of how charged macromolecules undergo phase separation. Clustering of similarly charged polymer chains is found to play an intermediary role during the primordial stages of the nucleation of the new stable phase, based on the limited preliminary data. The pro-posed research will establish the validity and general applicability of this newly discovered phenomenon.%%%The proposed research will have impact in medical research on disease control and a number of key industries including food, cosmetics, personal care products, and pharma-ceuticals. Furthermore, polyelectrolytes are emerging to be the most important, but least understood, materials. Training of graduate students in this important research area is the strong educational component of the proposed activity.