Segregation in Multicomponent Macromolecular Systems

多组分大分子系统中的分离

• 批准号: 0109610
• 负责人: Monica Olvera
• 金额: $ 19.5万
• 依托单位: Northwestern University
• 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: 2001-07-15 至 2005-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0109610&HistoricalAwards=false
• 关键词: Segregation; Multicomponent; Macromolecular; Systems

0109610OlveraThis theoretical research grant will model self-organization in certain classes of incompatible multicomponent macromolecular systems. Analytical and numerical models will be developed to determine the conformation of self-organized aggregates of charged and/or multiblock macromolecules. Both, charged chains and multiblock molecules, are capable of forming highly organized self-assembled structures with specific functions. This is evident in the biological world, since nucleic acids and most proteins are charged and/or heterogeneous macromolecules. We will determine the structure of simpler self-organized macromolecules designed for specific functions. In particular, we will determine the structure and thermodynamics of dilute and semidilute charged polymer solutions in various ionic media. Flexible polyelectrolytes, such as single strand DNA and polysterene sulphonate, for example, can undergo reversible expanded to compacted transformations where the size of the chains changes by orders of magnitude with the addition of multivalent particles of opposite charge. This suggests their application as sensors. Polyelectrolyte semidilute solutions, on the other hand, form physical gels in the presence of multivalent particles. We will study the self-organization of these polyelectrolytes and of other complex multiblock molecules, such as triblocks of asymmetric crystallizable rigid rods, spacer and bulky oil chains. These triblock molecules, self-organized into mushroom shaped nano-aggregates, are the first examples of achiral pure (non-mixture) longitudinal ferroelectric liquid crystals. Models to explain this organization will be developed, and the possibility of supramolecular polar order in other complex chemical structures, including charged coil units, will be determined. Finally, the project on hydrodynamic flow in multicomponent incompatible fluids, initiated during the last funding period, will be completed. We will analyze the effect of flow in ternary fluids where the minority component segregates at interfaces forming vesicle-like droplets (wetting case) or forming a liquid droplet at the interfaces (non-wetting case) by using the code developed to study flow in multicomponent liquids of different viscosities.%%%

0109610Olvera 这项理论研究资助将模拟某些类别的不相容多组分大分子系统的自组织。 将开发分析和数值模型来确定带电和/或多嵌段大分子的自组织聚集体的构象。 带电链和多嵌段分子都能够形成具有特定功能的高度组织的自组装结构。 这在生物世界中是显而易见的，因为核酸和大多数蛋白质都是带电荷的和/或异质大分子。 我们将确定为特定功能设计的更简单的自组织大分子的结构。 特别是，我们将确定各种离子介质中稀和半稀带电聚合物溶液的结构和热力学。 例如，柔性聚电解质，如单链 DNA 和聚苯乙烯磺酸盐，可以经历可逆的膨胀到压缩的转变，其中链的大小随着相反电荷的多价颗粒的添加而发生数量级的变化。 这表明它们作为传感器的应用。 另一方面，聚电解质半稀溶液在多价颗粒存在下形成物理凝胶。 我们将研究这些聚电解质和其他复杂多嵌段分子的自组织，例如不对称可结晶刚性棒、间隔基和大油链的三嵌段。 这些三嵌段分子自组织成蘑菇形纳米聚集体，是非手性纯（非混合物）纵向铁电液晶的第一个例子。 将开发解释这种组织的模型，并将确定其他复杂化学结构（包括带电线圈单元）中超分子极性顺序的可能性。 最后，在上一个资助期间启动的多组分不相容流体中的流体动力流动项目将完成。 我们将使用为研究多组分流动而开发的代码来分析三元流体中流动的影响，其中少数组分在界面处分离形成囊泡状液滴（润湿情况）或在界面处形成液滴（非润湿情况）不同粘度的液体。%%%