Highly Branched Nanostructures and their Assemblies

技术概述：该项目专注于理解新型高支链纳米结构定向组装的基本原理：(1)具有响应性离子块的星形嵌段共聚物和(2)具有多臂功能的高支链无机-有机纳米结构。将一套传统的表征工具扩展到中子小角散射和中子反射率，将有助于更深入地了解界面上复杂大分子组装的分子内和分子间组织。该小组将重点研究完全有机和混合有机-无机分支纳米结构在不同界面上的形态、微观结构和构象，作为化学成分、外部条件和表面拓扑/功能的函数。-星形嵌段共聚物的表面行为，重点研究在具有定制功能和地形的平面和模板表面上具有不同分子结构的离子嵌段的复杂星形共聚物，这些环境条件会改变响应离子嵌段的构象和组成；-设计和形成具有不同分支和化学组成的功能化臂的高支化无机-有机多面体低聚硅氧烷纳米结构及其在定制表面和界面上的组装行为；-了解新型“多光谱点”的表面行为和光谱特性，作为具有低光散射和吸收的无机-有机纳米结构，并将其定向组装成纳米工程材料。PI期望这些新型纳米结构组装在模板化的功能化表面上，并具有引导其组织的能力，可能具有潜在的有趣的响应和光谱特性，这对化学传感和柔性纳米复合材料等领域至关重要。非技术总结：预计该项目将对高级研究和高等教育产生影响。首先，对于具有独特物理（光学和表面）特性的新型有组织混合纳米材料的应用研究和开发的进一步进展至关重要，这些材料可应用于能量转换、比色和化学传感器等不同领域。第二，学生教育的进步将通过加强国际培训来实现，重点是早期参与与美国和欧洲不同的学术和政府研究实验室的跨学科合作。通过这种紧密的合作，研究将使博士生成为熟悉纳米材料前沿研究的成熟科学家。PI将继续努力，通过积极与GT的校长本科生研究奖和夏季本科生研究项目合作，增加攻读科学和工程高级学位的学生人数。PI将继续强调招募代表性不足的学生。PI的一名少数民族研究生将作为导师参与GT综合科学，数学和计算教育中心（CEISMC），与亚特兰大公立学校系统的少数民族初高中学生一起工作，帮助少数民族学生为大学生活做好准备。

TECHNICAL SUMMARY:The PI focuses on the understanding of fundamental principles of directed assembly of novel highly branched nanostructures: (1) star block copolymers with responsive ionic blocks and (2) highly branched inorganic-organic nanostructures with multiple arm functionalities. Expanding a traditional set of characterization tools to neutron small angle scattering and neutron reflectivity will allow deeper understanding of the intra- and intermolecular organization of complex macromolecular assemblies at interfaces. The group will focus on morphology, microstructure, and conformation of fully organic and hybrid organic-inorganic branched nanostructures at different interfaces as a function of chemical composition, external conditions, and surface topology/functionalities: -- surface behavior of star block copolymers with emphasis on complex stars with ionic blocks with different molecular architectures on planar and templated surfaces with tailored functionalities and topography under different environmental conditions which vary conformation and composition of responsive ionic blocks;-- design and the formation of highly branched inorganic-organic polyhedral oligomeric silsesquioxane nanostructures with different branching and chemical composition of functionalized arms and their assembling behavior at tailored surfaces and interfaces;-- the understanding of surface behavior and spectral properties of novel "multispectral dots" as inorganic-organic nanostructures with low light scattering and absorption and their directed assembly into nanoengineered materials.The PI expects that these novel nanostructures assembled onto templated functionalized surfaces with the ability to guide their organization might possess potentially intriguing responsive and spectral properties critical for such fields as chemical sensing and flexible nanocomposites. NON-TECHNICAL SUMMARY:An impact of this project is anticipated in both advanced research and higher education. First, the fundamental understanding will be critical for further progress in applied research and developments of novel organized hybrid nanomaterials with unique physical (optical and surface) properties that are applicable in such diverse fields as energy conversion, colometric and chemical sensors. Second, advances in student education will be achieved through internationally-enhanced training with emphasis on early involvement in interdisciplinary collaboration with diverse academic and government research labs in US and Europe. Through this intense collaboration, the research will enable Ph.D. students to become mature scientists familiar with cutting-edge research in nanomaterials. The PI will continue his efforts to increase the number of students pursuing advanced degrees in science and engineering by actively working with the President's Undergraduate Research Award and Summer Undergraduate Research Programs at GT. The PI places continued emphasis on recruiting under-represented students. One of PI's minority graduate students will be involved as a mentor with GT Center for Education Integrating Science, Math, and Computing (CEISMC) working with minority middle/high school students in Atlanta Public School System helping to prepare minority students for college life.