Adsorption of Charged Polymers

带电聚合物的吸附

• 批准号: 0102267
• 负责人: Michael Rubinstein
• 金额: $ 22.5万
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0102267&HistoricalAwards=false
• 关键词: Adsorption; Charged; Polymers

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.***

该奖项支持带电聚合物在表面和界面上吸附的理论和计算研究。研究重点将放在亲水性和疏水性聚电解质上。PI将在聚合物与表面之间存在短程和长程相互作用的情况下，建立亲水性聚电解质的吸附分析模型。De Gennes的非带电聚合物短程吸附的自相似地毯模型将与聚电解质长程吸附到相反带电表面的模型相结合。另一种模型将被用来研究疏水性聚电解质在短程和长程相互作用下的吸附。疏水性聚电解质在溶液中的性质将被更详细地研究，以使吸附模型能够扩展到疏水性聚电解质。短程吸引和长程(静电)斥力的相互作用导致了疏水聚电解质的项链构象。最近，计算机模拟和散射实验证实了疏水聚电解质项链模型的主要特征。对于将该模型应用于疏水性聚电解质的吸附来说，其余重要的未决问题将使用分析计算和计算机模拟相结合的方法进行研究。将得到的疏水性聚电解质溶液模型与亲水性聚电解质的吸附模型相结合，得到疏水性聚电解质的吸附模型。在非缠绕吸附层的Rouze-Zimm模型和缠绕层的管状模型的框架下，利用de Gennes的两步法建立了聚电解质在带电表面的吸附动力学理论。这笔赠款支持广泛的教育活动，从K-12到博士后研究助理的教育。该奖项还为编写聚合物物理教科书提供了部分支持。%该奖项支持理论和计算研究，这些研究有助于发展带电聚合物在带电表面吸附的完整分子图景。带电聚合物的吸附是聚合物物理学中最鲜为人知的领域之一。带电聚合物作为流变学改进剂、分散剂、稳定剂和粘结剂的技术重要性源于它们在溶液和近表面中的独特性能。在纳米科学和工程领域的一个应用是通过逐层沉积相反电荷的聚电解质来形成多层膜，从而产生了新的纳米器件制造方法。更好地了解带电聚合物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，而静电对它们的性质和功能起着重要的作用。该奖项还将支持广泛的教育活动，包括K-12推广和本科生、研究生和博士后水平的聚合物物理和化学教育。其中一些研究将包括在北卡罗来纳大学的聚合物物理化学课程序列中，以及正在编写的教科书中。