Self-Organization in Tethered Polymer Layers

系留聚合物层中的自组织

• 批准号: 9208527
• 负责人: Thomas Witten
• 金额: $ 24万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-01-15 至 1995-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9208527&HistoricalAwards=false
• 关键词: Self; Organization; Tethered; Polymer; Layers

A new physical state of long-chain polymers is becoming increasingly important in technology. In this state the ends of the polymer chains are forced to crowd together at a surface, thus causing them to elongate one another. The resulting stored elastic energy gives rise to striking spatial patterns and mechanical responses which have not been explained. Recently we have developed a new theoretical method for treating this mutually elongated state of 'end-confined" or "tethered" polymers. We will apply the method to understand the layer of end-grafted polymers often used to stabilize colloidal particles. We will calculate the functional form of the osmotic-pressure corona around such particles responsible for steric stabilization. End-confined polymers in, for instance, a lamellar stack of copolymer layers flow in a distinctive way because their entanglements are quite different from those in simple polymer liquids. We will calculate the relaxation of stress with time in this state using recent theories of entangled-polymer motion. We will explore the distinctive local elastic properties of the layer by calculating the linear response of the pressure to a nearby perturbation of the density. Finally, we will calculate the interaction energy induced by bridging of surfaces, for instance by triblock polymers. %%% Theoretical research will be undertaken on the properties of polymers which are attached at one end to a surface. This attachment causes the polymers to interact in a way which produces unusual properties which will be explored in this research. The results of this work will produce a deeper understanding of this class of polymers and provide a foundation for commercial application.

长链聚合物的一种新的物理状态正在成为 在技术上越来越重要。 在这种状态下， 聚合物链被迫在表面挤在一起， 使它们彼此拉长。 生成的存储弹性 能源产生了惊人的空间格局和机械 没有解释的回答。 最近我们 发展了一种新的理论方法来处理这个相互 “端部受限”或“栓系”聚合物的伸长状态。 我们将 应用该方法来理解末端接枝聚合物层 通常用于稳定胶体颗粒。 我们将计算 围绕着这些的南极压力日冕的功能形式 负责空间稳定的颗粒。 端部受限 例如，共聚物层的层状叠层中的聚合物 以一种独特的方式流动，因为它们的纠缠相当 不同于简单的聚合物液体。 我们将计算 在这种状态下，使用最近的应力随时间的松弛 缠结聚合物运动的理论 我们将探讨 通过计算， 压力对附近扰动的线性响应 密度的 最后，我们将计算诱导的相互作用能 通过表面的桥接，例如通过三嵌段聚合物。 %%% 本文将从理论上研究 聚合物，其一端附着在表面上。 这 附着导致聚合物以一种产生 这些不寻常的特性将在本研究中进行探索。 的 这项工作的结果将产生更深刻的理解这一点 类聚合物，并提供了商业基础 应用程序.