RII Track-4: Advanced Morphology Characterization of Nanostructured Cyclic and Linear Polymers and their Blends

非技术说明在过去的三十年里，微电子和医疗保健行业取得了巨大的进步，产生了比最早的计算机更强大的电话，以及更有效、侵入性更小、能够治疗以前无法治疗的疾病的医疗方法。这种快速的技术增长是由于新材料的创造和充分了解其化学和物理性质的努力。为了保持这种水平的增长，必须继续寻找新材料。该项目支持大学研究人员和来自政府实验室的科学家在这项研究中的合作。在一个领域，对嵌段共聚物(一种纳米结构橡胶塑料材料)性质的基础研究有望开辟一条在纳米尺度上进行平版印刷的新途径，以促进从微电子到纳米电子的转变，后者速度更快，数据存储能力更强。在第二个领域，对生物相容、可生物降解的半结晶聚合物的研究将减少对控制结晶的不受欢迎的小分子添加剂的需求，从而提高用于医疗应用的生物兼容性和安全性。该项目通过支持只能在最先进的国家实验室进行的实验来促进科学进步。通过促进学术界和政府之间的密切互动，该项目培训学生将他们的教育经历与国家健康、繁荣、福利和培养具有公民意识的科学家和工程师的目标联系起来。技术说明环状分子结构赋予聚合物材料独特而有用的物理性能，如嵌段共聚物中较小的纳米结构微区尺寸和更大的薄膜稳定性。这些聚合物显示出作为添加剂的巨大潜力，使线性聚合物体系具有理想的性能。然而，线型和环型材料在拓扑共混物中的分子水平整合还不是很清楚。通过该研究会开展的高级表征实验提供了必要的基础知识，以了解如何使用拓扑共混物(线性和环状聚合物)来(1)增强用于纳米光刻的嵌段共聚物的纳米结构性能，以及(2)调节半结晶聚合物薄膜中的结晶动力学和形态。通过使用共振软X射线反射率(RSoXR)来表征嵌段共聚体系中的分子分布和宽带相干反斯托克斯拉曼散射(CARS)来描绘半结晶聚合物共混膜中的局域组分，来揭示这些体系中的分子机制，从而实现这些目标。主办方现场访问，即PI和学生与国家标准与技术研究所的专家密切合作，对于理解分子水平上的材料组织和维持长期的学术与政府合作非常重要。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Non-Technical DescriptionOver the past thirty years, tremendous advancements have occurred in the microelectronics and healthcare industries, resulting in phones that are more powerful than the earliest computers and medical treatments that are more effective, less invasive, and capable of treating formerly untreatable ailments. This rapid technological growth was enabled by the creation of new materials and efforts to fully understand their chemical and physical properties. In order to sustain this level of growth, the search for new materials must continue. This project supports collaboration between university researchers and scientists from government laboratories in this search. In one area, fundamental research into the properties of block copolymers, a type of nanostructured rubbery plastic material, promises a new route to lithographic patterning on the nano-scale to facilitate the move from micro-electronics to nano-electronics that are faster and capable of greater data storage. In a second area, studies on biocompatible, biodegradable, semi-crystalline polymers will reduce the need for undesirable small molecule additives to control crystallization, thereby enhancing biocompatibility and safety for use in medical applications. The project promotes scientific advancement by supporting experiments that can be conducted only in state-of-the-art national laboratories. By nurturing close interactions between academia and government, the project trains students to connect their educational experiences to the goals of national health, prosperity, welfare, and the production of civically-mindful scientists and engineers. Technical DescriptionThe cyclic molecular architecture endows polymer materials with unique and useful physical properties compared to linear counterparts such as smaller nanostructure domain sizes in block copolymers and greater thin film stability. These polymers show great promise as additives for endowing linear polymer systems with desirable properties. However, the molecular level integration of linear and cyclic materials in topological blends is not well-understood. Advanced characterization experiments made possible through this fellowship produce the fundamental knowledge necessary to understand how topological blends (linear plus cyclic polymers) can be used to (1) enhance block copolymer nanostructure properties for nanolithgraphy and (2) regulate crystallization kinetics and morphology in semi-crystalline polymer films. These goals are achieved by revealing molecular mechanisms in these systems using resonant soft X-ray reflectivity (RSoXR) for the characterization of molecular distributions in block copolymer systems and broadband coherent anti-Stokes Raman scattering (CARS) for mapping the localization components in semi-crystalline polymer blend films. Host site visits, in which the PI and students work closely with experts at the National Institute of Standards and Technology, are important for understanding organization of materials at the molecular level and for sustaining long-term academic-government collaboration.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.