DMREF: Engineering Organic Glasses

技术摘要：在材料基因组计划下，在NSF DMR的支持下，Lian Yu，Mark Ediger，Juan de Pablo和他们的同事将研究工程有机玻璃。玻璃是一种重要的材料，它结合了固体的优点(包括机械稳定性)和液体的优点(包括宏观空间一致性)，使其成为广泛应用的理想材料。然而，玻璃本质上是非平衡材料，这使得它们的研究和设计特别具有挑战性。虽然常见的玻璃是无机和聚合物的，但相对低分子量的有机玻璃在电子、生物保护和药物输送方面得到了应用。该团队寻求创建一个知识库，并制定有机玻璃工程的设计原则。这项工作建立在晶体和无机玻璃工程的先前进展以及有机玻璃领域的最新发现的基础上，特别是通过物理气相沉积(PVD)创造出具有可调各向异性的高密度和高稳定性玻璃。一个协调一致的实验和模拟计划将针对有机玻璃工程的三个领域，这些领域具有技术相关性，但目前缺乏了解：(1)控制各向异性，(2)控制分子构象，(3)抑制结晶。在目标1下，该团队将研究PVD、外场和液晶顺序在有机玻璃中各向异性的产生和控制。虽然通常是各向同性的，但具有受控各向异性的玻璃在数据存储、非线性光学和激光技术方面有潜在的应用。Aim 2的工作是在主动控制分子构象的同时生产有机玻璃。构象柔性是有机玻璃许多分子组成的特征；控制构象为优化其性质(例如，HOMO/LUMO水平和电荷迁移率)提供了独特的机会。根据目标3，该团队将使用聚合物添加剂稳定有机玻璃的结晶。这种能力将使前景看好但容易结晶的有机玻璃成为耐用的无定形材料。所有领域的工作都将以高通量的方式进行，模拟将用于筛选实验材料和条件的选择，并解释实验数据。非技术综述：玻璃是一种非晶态材料，它结合了类似固体的机械稳定性和类似液体的空间均匀性，使其成为从电信到生物保护的许多应用的理想选择。本研究旨在推进有机玻璃的科学技术，其结果将为通过模拟和有针对性的实验协同使用来设计具有所需性能的有机玻璃提供基础。这项研究将使玻璃和非晶态材料重要的其他领域的材料科学家和工程师受益，并有助于从更广泛的角度看待玻璃科学。稳定非晶态材料防止结晶的能力的提高将特别有利于制药科学家，因为他们正在开发非晶态配方，以提供高效但难于溶解的药物。较差的溶解性限制了许多药物的开发，这些药物将显著促进美国和发展中国家的医疗保健。除了期刊出版物，这项工作的结果还将通过中央网站传播，这一机制对于归档和共享来自高通量研究的广泛数据尤为重要。研究生和本科生将受益于该项目的多学科性质，有大量接触模拟和实验、晶体和玻璃以及聚合物和低分子质量材料。这笔助学金支持的人员将与威斯康星大学麦迪逊分校的大学前卓越学习丰富机会计划(People)合作，该计划在增加少数族裔和低收入高中生在高校的招生方面有着良好的记录。该计划提供经验，帮助学生成为具有科学素养的公民，并鼓励他们考虑在科学和工程领域就业。

TECHNICAL SUMMARY: With support from the NSF DMR under the Materials Genome Initiative, Lian Yu, Mark Ediger, Juan de Pablo, and their coworkers will study Engineering Organic Glasses. Glasses constitute an important class of materials that combine the advantages of solids, including mechanical stability, with the advantages of liquids, including macroscopic spatial uniformity, making them ideal for a wide range of applications. Glasses, however, are inherently non-equilibrium materials, which makes their study and design particularly challenging. While familiar glasses are inorganic and polymeric, organic glasses of relatively low molecular weights are finding applications in electronics, bio-preservation, and drug delivery. The team seeks to create a knowledge base and develop design principles for the engineering of organic glasses. The effort builds on previous progress in the engineering of crystals and inorganic glasses, as well as recent discoveries in the field of organic glasses, in particular, the creation of high-density and high-stability glasses with tunable anisotropy by physical vapor deposition (PVD). A concerted program of experiments and simulations will target three areas of organic glass engineering that have technological relevance and where current understanding is lacking: (1) controlling anisotropy, (2) controlling molecular conformation, and (3) inhibiting crystallization. Under Aim 1, the team will study the creation and control of anisotropy in organic glasses by PVD, external fields, and liquid-crystal order. Though often isotropic, glasses with controlled anisotropy have potential applications in data storage, non-linear optics, and laser technologies. Work under Aim 2 seeks to produce organic glasses while actively controlling molecular conformation. Conformational flexibility characterizes many molecular components of organic glasses; controlling conformation offers a unique opportunity in optimizing their properties (e.g., HOMO/LUMO levels and charge mobility). Under Aim 3, the team will stabilize organic glasses against crystallization using polymer additives. This capability will enable promising but easy-to-crystallize organic glasses to serve as durable amorphous materials. Work in all areas will be performed in a high-throughput manner, with simulations used to screen the selection of materials and conditions for experimentation, and to interpret experimental data. NON-TECHNICAL SUMMARY:Glasses are amorphous materials that combine solid-like mechanical stability and liquid-like spatial uniformity, making them ideal for many applications ranging from telecommunication to bio-preservation. This research seeks to advance the science and technology of organic glasses, and the results will provide a foundation for designing organic glasses with desired properties through concerted use of simulations and targeted experiments. This research will benefit materials scientists and engineers in other fields where glasses and amorphous materials are important, and contribute to a broader perspective on the science of glasses in general. The improved ability to stabilize amorphous materials against crystallization will especially benefit pharmaceutical scientists as they develop amorphous formulations to deliver highly potent but poorly soluble drugs. Poor solubility is limiting the development of many drugs that would significantly advance health care in the U.S. and developing countries. In addition to journal publications, results from this work will be disseminated via a central website, a mechanism especially important for archiving and sharing the extensive data from high-throughput investigations.Graduate and undergraduate students will benefit from the multi-disciplinary nature of this project, having significant exposure to simulations and experiments, crystals and glasses, and polymeric and low-molecular-weight materials. Personnel supported by this grant will work with UW-Madison's Pre-college Enrichment Opportunity Program for Learning Excellence (PEOPLE), which has a proven record of increasing the enrollment of minority and low-income high school students in colleges and universities. This program provides experiences that help students to become scientifically literate citizens and encourages them to consider careers in science and engineering.