Rational Framework for Particle-containing Coacervates

含颗粒凝聚层的合理框架

• 批准号: 1804177
• 负责人: Sarah Perry
• 金额: $ 35.77万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1804177&HistoricalAwards=false
• 关键词: Rational; Framework; Particle; containing; Coacervates

Coacervates are complexes of oppositely charged polymers that have separated into two liquid phases from a salt solution due to electrostatic forces. They are used in coatings, adhesives, pharmaceuticals, and personal care products. This research will create novel coacervates in which one of the charged components is a solid nanoparticle. The work will create new coacervates by building on existing knowledge, explore how particle size and rigidity affect the formation of the two liquid phases, and examine the role that the arrangement of charges on the particle surface plays. Experiments to map the phase diagrams for these new materials will be complemented by analysis, experiments to identify the adsorption of polymers on the particle surfaces and the polymer configurations, and experiments to measure the bulk mechanical behavior. Ultimately, the researchers plan to identify design rules for the formulation of coacervates using a broad class of particles. Research opportunities for women and other students who are under-represented in STEM fields will be provided as part of this work.This award is focused on a systematic study of polymer-particle coacervates. Three specific aims for the work are: 1) create polymer-particle coacervates employing particles with polymers attached (brushy particles) to build upon the current understanding of polymer-polymer coacervate systems, 2) examine how particle rigidity and size impact coacervate formation and properties, and 3) examine the role of charge clustering on coacervate formation by focusing on electrostatically patchy particles. The three aims decouple the hypothesized mechanisms by which particle properties affect coacervate formation, thus providing design rules for the formulation of coacervates using broad classes of particles. By comparing coacervate formation with brushy particles to the analogous system of linear polycation and polyanion chains, Aim 1 preserves the molecular interactions of a classical coacervate and introduces solid particles as space filling entities whose length scales may be important through their range of interactions. Aims 2 and 3 sequentially probe the impact of molecular scale constraints introduced by particle rigidity, potential mismatch in registration of positive and negative charge, and charge clustering. The program exploits the synergy between the principle investigators: Perry (coacervate expert) and Santore (expert on polyelectrolyte adsorption and colloidal phase behavior). The experiments at UMass will be supported by computations by collaborator Sing at UIUC whose calculations address both the polymer-solid interactions and the phase behavior.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

凝聚层是带相反电荷的聚合物的复合物，由于静电力而从盐溶液中分离成两个液相。 它们用于涂料、粘合剂、药品和个人护理产品。 这项研究将创建新型凝聚层，其中带电成分之一是固体纳米颗粒。 这项工作将在现有知识的基础上创建新的凝聚层，探索颗粒尺寸和刚性如何影响两个液相的形成，并检查颗粒表面电荷排列所起的作用。 绘制这些新材料相图的实验将通过分析、确定聚合物在颗粒表面上的吸附和聚合物构型的实验以及测量整体机械行为的实验来补充。 最终，研究人员计划确定使用多种颗粒配制凝聚层的设计规则。 作为这项工作的一部分，将为 STEM 领域代表性不足的女性和其他学生提供研究机会。该奖项的重点是聚合物颗粒凝聚层的系统研究。 这项工作的三个具体目标是：1) 使用附着有聚合物的颗粒（刷状颗粒）创建聚合物-颗粒凝聚层，以建立目前对聚合物-聚合物凝聚层系统的理解，2) 检查颗粒刚性和尺寸如何影响凝聚层的形成和性能，以及 3) 通过关注静电斑片颗粒来检查电荷聚集对凝聚层形成的作用。 这三个目标将粒子特性影响凝聚层形成的假设机制解耦，从而为使用广泛类别的粒子配制凝聚层提供设计规则。通过将刷状颗粒形成的凝聚层与线性聚阳离子和聚阴离子链的类似系统进行比较，目标 1 保留了经典凝聚层的分子相互作用，并引入固体颗粒作为空间填充实体，其长度尺度通过其相互作用范围可能很重要。目标 2 和 3 依次探讨由颗粒刚性、正负电荷记录中的潜在不匹配以及电荷聚集引入的分子尺度限制的影响。 该计划利用了主要研究人员 Perry（凝聚专家）和 Santore（聚电解质吸附和胶体相行为专家）之间的协同作用。麻省大学的实验将得到 UIUC 合作者 Sing 的计算支持，他的计算解决了聚合物-固体相互作用和相行为。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。