Adsorption of Charged Polymers

0102267 Rubinstein该奖项支持带电聚合物在表面和界面吸附的理论和计算研究。 研究将集中在亲水性和疏水性聚电解质。 PI将开发在聚合物和表面之间存在短程和长程相互作用的情况下亲水性聚电解质吸附的分析模型。 De Gennes的不带电聚合物短程吸附的自相似地毯模型将与聚电解质对相反电荷表面的长程吸附模型相结合。另一个模型将被开发来研究在存在短程和长程相互作用的情况下的疏水吸附。 疏水聚电解质在溶液中的性质将进行更详细的研究，使疏水聚电解质的吸附模型的扩展。短程吸引和长程（静电）排斥的相互作用导致疏水聚电解质的项链构象。计算机模拟和散射实验最近证实了项链模型的疏水聚电解质的主要特点。剩余的开放问题的重要应用模型的疏水聚电解质的吸附将使用分析计算和计算机模拟相结合的研究。将所得的疏水聚电解质溶液模型与亲水聚电解质的吸附模型结合成疏水聚电解质的吸附模型，在Rouze-Zimm模型（非缠结吸附层）和管模型（缠结吸附层）的框架下，用de Gennes的两步法发展了疏水聚电解质在带电表面上的吸附动力学理论。 广泛的教育活动，跨越K-12推广到博士后研究助理的教育都得到了这笔赠款的支持。该奖项还为编写高分子物理教科书提供了部分支持。%该奖项支持理论和计算研究，有助于发展带电聚合物在带电表面上吸附的完整分子图像。 带电聚合物的吸附是聚合物物理学中最不为人所知的领域之一。带电聚合物作为流变改性剂、分散助剂、稳定剂和粘合剂的技术重要性是由于它们在溶液和近表面中的独特性质。在纳米级科学和工程领域的应用是通过逐层沉积带相反电荷的聚电解质形成多层，从而产生纳米器件制造的新方法。 对带电聚合物的更好理解也将影响分子生物物理学，因为许多生物聚合物，如DNA和蛋白质，都是带电的，静电在它们的性质和功能中起着重要作用。该奖项还将支持广泛的教育活动，包括K-12推广和本科，研究生和博士后水平的聚合物物理和化学教育。一些研究将包括在聚合物物理化学课程序列在斯坦福大学和正在编写的教科书中。*

0102267RubinsteinThis award supports theoretical and computational research on charged polymer adsorption at surfaces and interfaces. Research will focus on hydrophilic and hydrophobic polyelectrolytes. The PI will develop an analytical model of adsorption of hydrophilic polyelectrolytes in the presence of short-range and long-range interactions between polymers and surfaces. De Gennes' self-similar carpet model of short-range adsorption of uncharged polymers will be combined with a model of long-range adsorption of polyelectrolytes to oppositely charged surfaces. Another model will be developed to study hydrophobic polyelectrolyte adsorption in the presence of both short-range and long-range interactions. The properties of hydrophobic polyelectrolytes in solution will be studied in more detail to enable the extension of adsorption models to hydrophobic polyelectrolytes. The interplay of short-range attraction and long-range (electrostatic) repulsion leads to a necklace conformation of hydrophobic polyelectrolytes. Computer simulations and scattering experiments have recently confirmed the main features of the necklace model of hydrophobic polyelectrolytes. The remaining open questions important for the application of the model to the adsorption of hydrophobic polyelectrolytes will be investigated using a combination of analytical calculations and computer simulations. The resulting model of hydrophobic polyelectrolyte solutions will be combined with the adsorption model of hydrophilic polyelectrolytes into an adsorption model of hydrophobic polyelectrolytes.The kinetic theory of polyelectrolyte adsorption at charged surfaces will be developed using de Gennes' two-step approach in the framework of Rouze-Zimm model for unentangled adsorbed layers and of tube models for entangled layers. A wide range of educational activities spanning K-12 outreach to the education of postdoctoral research associates are supported by this grant. This award also provides partial support of the preparation of a polymer physics textbook.%%%This award supports theoretical and computational research that contributes toward the development of a complete molecular picture of the adsorption of charged polymers on charged surfaces. Adsorption of charged polymers is one of the least understood areas of polymer physics. The technological importance of charged polymers as rheology modifiers, dispersing aids, stabilizers, and binders is due to their unique properties both in solutions and near surfaces. An application in the area of nanoscale science and engineering is multilayer formation via layer-by-layer deposition of oppositely charged polyelectrolytes, leading to novel methods of nanodevice fabrication. A better understanding of charged polymers will also impact molecular biophysics because many biopolymers, such as DNA and proteins, are charged, and electrostatics plays a significant role in their properties and function. The award will also support a wide range of educational activities including K-12 outreach and education in polymer physics and chemistry at the undergraduate, graduate, and postdoctoral levels. Some of the research will be included in the Polymer Physical Chemistry course sequence at UNC and in a textbook that is in preparation.***