Using instabilities of fluid interfaces to assemble amphiphilic block copolymers

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。本提案的目标是通过不混相流体界面的水动力不稳定性来发展对两亲性嵌段共聚物组装新工艺路线的基本界面和传输现象的理解。尽管引起聚合物组装的不稳定性与小分子表面活性剂体系和反应性聚合物共混物中成熟的工艺密切相关，但关于引起不稳定性的基本条件以及随后的界面变形如何发生的许多基本问题仍然存在。在目前的提案中，我们也试图了解如何有效地利用这一过程来产生具有新结构和独特性能的聚合物胶束和微粒。本研究将对界面现象、聚合物物理和生物医学领域做出以下有价值的具体贡献：使用系统变化的聚合物组成和溶剂条件，测试所提出的由有机/水界面张力消失引起的流体动力学不稳定性机制的有效性。-详细了解：(i)有机/水界面的不稳定后演变如何取决于两亲性聚合物的性质，（ii）如何使用助表面活性剂调整这种行为，以及（iii）聚合物在此过程中质量传递的重要性。-明确的路线，以制备具有独特性能的新型聚合物组件：(i)球形和蠕虫状胶束，封装各种功能纳米粒子物种；（ii）具有纳米和微纹理表面的聚合物微粒，允许定制颗粒表面特性。更广泛的影响这个项目将在科学和教育方面产生广泛的影响。从科学上讲，对界面不稳定性的洞察将为相关过程提供基本的见解，这些过程隐含着肥皂如何达到最佳去污力以及如何最好地混合不混相聚合物等技术上的重要问题。将开发用于生产多功能胶束和有纹理的微颗粒的简单路线，以及将获得的对这些组件特性的理解，将在生物医学背景下用于药物输送和纳米医学的应用中具有相当大的实用性。在教育方面，这个研究项目将有助于培养来自不同背景的研究生和本科生，无论是在课堂上还是在多学科的研究环境中。研究结果还将通过一系列外联活动向更广泛的公众传播，包括由PI发起的与波士顿科学博物馆的合作。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).0931616HaywardIntellectual MeritThe goal of this proposal is to develop an understanding of the basic interfacial and transport phenomena underlying a newly developed processing route for assembling amphiphilic block copolymers through hydrodynamic instabilities of immiscible fluid interfaces. Though the instabilities that give rise to polymer assembly are closely related to well established processes in small molecule surfactant systems and reactive polymer blends, many fundamental questions remain about the basic conditions that give rise to the instabilities, as well as how subsequent deformation of the interface takes place. In the current proposal, we also seek to understand how this process can be effectively harnessed to generate polymeric micelles and microparticles with new structures and unique properties. The proposed research will make the following specific contributions, which will be of value to the fields of interfacial phenomena, polymer physics, and biomedicine:Tests of the validity of the proposed mechanism that the hydrodynamic instability arises from a vanishing tension of the organic/water interface, using a systematically varying series of polymer compositions and solvent conditions.- A detailed understanding of: (i) how the post instability evolution of the organic/water interface depends on the properties of the amphiphilic polymer, (ii) how to tune this behavior using co-surfactants, and (iii) the importance of mass transport of polymer in this process.- Well defined routes to prepare new types of polymer assemblies with unique properties: (i) spherical and wormlike micelles that encapsulate a variety of functional nanoparticulate species, and (ii) polymer microparticles with nano and micro textured surfaces that allow tailoring of particle surface properties.Broader ImpactsThis program will have broad impacts, both scientifically and educationally. Scientifically, the insights into interfacial instabilities will provide fundamental insights on related processes underlying the technologically important questions of how soaps achieve optimal detergency, and how immiscible polymers can best be blended. The simple routes that will be developed to produce multi functional micelles and textured microparticles, as well as the understanding that will be gained of the properties of these assemblies, will be of considerable utility in biomedical contexts for applications in drug delivery and nano medicine. Educationally, this research program will contribute to the training of graduate and undergraduate students from diverse backgrounds, both in a classroom setting and in a multi-disciplinary research environment. The results will also be communicated to the broader public through a series of outreach activities, including a partnership with the Boston Museum of Science initiated by the PI.