Temperature-Sensitive Complex Fluids

* 非技术摘要 * 本实验项目将探索复杂流体的基本性质，如胶体悬浮液、乳液、聚合物和表面活性剂溶液、液晶及其混合物。 这些软材料在涂料、食品科学和化妆品工业中，在流体流动和微流体的实际控制中，在细胞组织生物学中，以及在需要新的材料设计和加工方法的高技术问题中，如光子学、光刻、生物化学传感器中找到应用。 具体来说，这项研究将创造新材料来阐明各种基本现象，如熔化、结晶、堵塞、挫折和其他类型的自组装。 所获得的知识将提高我们直接观察和操纵微观和纳米颗粒以及更普遍的溶液中大分子的能力。 这项研究，反过来，为上述实际问题提供了见解。 作为这项研究的一部分开发的技术具有潜在的经济效益，例如，它导致了两个初创纳米技术公司的形成，以及与总部设在PA的一个更大的公司的广泛合作。 该计划还将教育新一代的科学家和工程师关于软材料和光学技术;这些学生和博士后加强国家的技术基础设施。 * 技术摘要 * 该计划提出了复杂流体的实验，以阐明诸如熔化和自组装的影响。 复杂流体是软材料，包括胶体悬浮液、乳液、聚合物表面活性剂溶液、液晶及其混合物。 这些软材料在各种应用中找到了应用。日常产品？软材料的概念也被证明对理解细胞组织生物学以及开发光子学、光刻和生物化学传感领域的高技术材料是有用的。 本计划的一个统一特征是基于温度敏感聚合物的小颗粒的创建和使用。 这些颗粒响应于环境刺激（如温度）而膨胀和收缩，从而使实验者能够诱导相变，然后可以通过光学显微镜和散射技术原位研究相变。 这项研究将阐明广泛的现象，包括几何挫折，熔化机制在二维和三维，在几层膜，干扰，和手性不稳定性的粒子？管子？ 该计划将培养新一代的科学家和工程师关于软材料，光学显微镜和显微操作，所获得的知识将教我们在溶液中操纵微米和纳米粒子，从而提供洞察上述实际问题。

****NON-TECHNICAL ABSTRACT****This experimental program will explore the fundamental properties of complex fluids such as colloidal suspensions, emulsions, polymer and surfactant solutions, liquid crystals, and mixtures thereof. These soft materials find applications in the paint, food science, and cosmetics industries, in the practical control of fluid flow and micro-fluidics, in cell & tissue biology, and in high-technology problems such as photonics, lithography, biochemical sensors which require new approaches to materials design and processing. Specifically, the research will create new materials to elucidate a variety of basic phenomena such as melting, crystallization, jamming, frustration and other classes of self-assembly. Knowledge gained will improve our ability to directly observe and manipulate micro- and nano-particles and, more generally, macromolecules in solution. This research, in turn, offers insight for the practical problems listed above. Technology developed as part of this research has potential economic benefit, e.g. it has led to the formation of two start-up nanotechnology companies as well as a broad collaboration with a much larger company based in PA. The program will also educate a new generation of scientists and engineers about soft materials and about optical techniques; these students and post-docs strengthen the technological infrastructure of the nation. ****TECHNICAL ABSTRACT****This program proposes experiments on complex fluids to elucidate effects such as melting and self-assembly. Complex fluids are soft materials including colloidal suspensions, emulsions, polymer & surfactant solutions, liquid crystals, and mixtures thereof. These soft materials find applications in a variety of ?everyday products? such as the paint, food and cosmetics; soft materials concepts are also proving to be useful for understanding cell & tissue biology, and for developing high-technology materials in photonics, lithography and biochemical sensing. A unifying feature of the present program is the creation and use of small particles based on temperature-sensitive polymers. These particles swell and contract in response to environmental stimuli such as temperature, and thereby enable experimenters to induce phase transformations that can then be studied in-situ by optical microscopy and scattering techniques. The research will elucidate a wide-range of phenomena including geometric frustration, melting mechanisms in two- and three-dimensions and in few-layer films, jamming, and the chiral instabilities of particles in ?tubes?. The program will train a new generation of scientists and engineers about soft materials, optical microscopy and micromanipulation, and the knowledge gained will teach us to manipulate micro- and nano-particles in solution, thereby offering insight into the practical problems listed above.