RUI: Dual Domain Organogels: A Novel Material Platform

第1部分：非技术概述聚合物凝胶是一种固体状材料，主要由液体组成。它们出现在各种各样的应用中，从食品和化妆品到农业用途，到药品和生物医学设备，也与水的可持续性有关。到目前为止，几乎所有关于“负载凝胶”的研究都集中在水基材料上，因为水丰富、用途广泛、具有生物相容性。然而，由碳氢化合物溶剂（例如矿物油）而不是水组成的负载凝胶具有许多优点，包括大大提高了保质期，消除了复杂的水-聚合物和水-纳米载体相互作用。这个本科院校研究项目将提供一种制造装载纳米载体的碳氢化合物基凝胶的方法。然后，将建立凝胶配方量与所得纳米级结构以及随后的纳米级结构与纳米载体的释放速度和凝胶物理特性（例如柔韧性和强度）之间的关联原理。这些结果将为负载凝胶纳米结构对实际性能的孤立影响提供基本的理解。此外，研究结果将有助于未来负载凝胶材料在健康、农业、水可持续性和相关行业的发展。与技术贡献同等重要的是，这项工作将部分由STEM本科生进行，从而培养他们的科学/技术专长和兴趣。学生们还将接触到国家实验室的尖端仪器和研究。首席研究员将在这些有抱负的工程师/科学家的支持下，将获得的知识应用于本科教学和初中/高中的推广活动。第2部分：技术概述聚合物凝胶扩展了大分子的用途，包括它们装载纳米载体的能力，如胶束、囊泡和纳米颗粒。负载纳米载体的聚合物凝胶比其独立成分（即，含有有效载荷的凝胶和分散在液体中的纳米载体）表现出优越的性能，这在需要高有效载荷存储和缓慢稳定释放的应用中特别有益，例如在农业和药物输送设备中。该RUI奖支持负载嵌段共聚物有机凝胶（称为双畴有机凝胶（DDOGs）或其嵌段共聚物和纳米载体域）的研究，其中溶剂和嵌段共聚物为非极性碳氢化合物，纳米载体为反胶束。这种组合消除了水凝胶中存在的复杂的、远距离的相互作用，如静电和偶极-偶极力，也消除了对单一溶剂的依赖，并大大延长了保质期。这项工作的目标包括：(i)合成DDOGs的配方-结构设计规则，以便它们的许多纳米级特征可以有系统地定制，以及（ii）建立定制有机凝胶中反向胶束扩散和机械行为的结构-性能关系。这项工作的结果不仅将促进科学界对负载凝胶配方和特性的理解，而且还可能为这些材料在许多高影响力技术中的使用提供信息，包括传感器、水净化、离子交换过程（例如电池）、农业和健康。同样重要的是，这项工作将培养STEM本科生的职业生涯，包括在国家实验室操作尖端仪器、解释结果数据和展示他们的发现的特殊经验。在这些有抱负的工程师/科学家的支持下，首席研究员将把获得的知识扩展到本科教学和初中/高中的推广活动中。该奖项反映了美国国家科学基金会的法定使命，并通过基金会的智力价值和更广泛的影响审查标准进行了评估，认为值得支持。

Part 1: NON-TECHNICAL SUMMARYPolymer gels are solid-like materials that are mostly composed of liquid. They appear in a wide variety of applications ranging from food and cosmetic products, to agricultural uses, to pharmaceuticals and biomedical devices, and also are relevant to water sustainability. Nearly all research on "loaded gels" thus far has concentrated on water-based materials since water is abundant, versatile, and biocompatible. However, loaded gels comprised of hydrocarbon solvent (e.g., mineral oil), instead of water, offer many benefits including greatly improved shelf life and elimination of complicated water-polymer and water-nanocarrier interactions. This RUI (Research in Undergraduate Institutions) project will deliver an approach to fabricate hydrocarbon-based gels loaded with nanocarriers. Then, principles correlating gel formulation quantities with resultant nanoscale structure and subsequently nanoscale structure with release rate of the nanocarriers and gel physical characteristics (e.g., flexibility and strength) will be established. These results will provide a fundamental understanding of the isolated effects of loaded gel nanostructure on practical properties. Furthermore, the findings will contribute to future developments of loaded gel materials in the health, agricultural, water-sustainability, and related industries. Of equal importance to its technical contributions, this work will be partially conducted by undergraduate STEM students, thereby cultivating their scientific/technical expertise and interests. The students will also be exposed to cutting-edge instrumentation and research at national laboratories. The principal investigator, along with support from these aspiring engineers/scientists, will apply acquired knowledge in undergraduate teaching and middle/high school outreach activities.Part 2: TECHNICAL SUMMARYPolymer gels extend the usefulness of macromolecules, including their ability to be loaded with nanocarrier species such as micelles, vesicles, and nanoparticles. Nanocarrier-loaded polymer gels exhibit superior properties over their stand-alone constituents (i.e., payload-containing gels and nanocarriers dispersed in liquids), which is particularly beneficial in applications where high payload storage and slow, steady release are desired, such as in agricultural and pharmaceutical delivery devices. This RUI award supports investigation of loaded block copolymer organogels (referred to as dual domain organogels (DDOGs) or their block copolymer and nanocarrier domains) wherein the solvent and block copolymer are nonpolar hydrocarbons and the nanocarriers are reverse micelles. This makeup eliminates the complex, long-range interactions, such as electrostatic and dipole-dipole forces, present in hydrogels as well as eradicates dependence on a single solvent and greatly extends shelf-life. Objectives of the work include: (i) synthesis of formulation-structure design rules for DDOGs such that a number of their nanoscale features can be methodically tailored, and (ii) establishment of structure-property relationships for reverse micelle diffusion and mechanical behavior in the tailored organogels. The results from this work will not only advance the scientific communities' understanding of loaded gel formulation and properties, but may also inform use of these materials in a number of high-impact technologies including sensors, water purification, ion-exchange processes (e.g., batteries), agriculture, and health. Of equal importance, the work will cultivate the careers of undergraduate STEM students including exceptional experiences to operate cutting-edge instrumentation at national laboratories, interpret resultant data, and present their findings. The principal investigator, along with support from these aspiring engineers/scientists, will extend acquired knowledge to inform undergraduate teaching and middle/high school outreach activities..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.