Polymer-Based Capsules of Active Liquids Templated by Non-Aqueous Emulsions

非技术性总结：科学家和工程师们继续开发新材料，以提高电池、水净化、气体吸收等应用的性能。这些新材料为创造新技术提供了基础，这些新技术几乎影响和改善了现代生活的方方面面。不幸的是，一些新材料，如离子液体和低共熔溶剂，很难单独处理，它们需要某种形式的密封，限制了它们在实际系统中的使用。这项研究工作通过开发方法来制备具有包裹在聚合物壳中的专用液体核心的胶囊来解决目前的这些限制。该方法通过使用由分散在油中的活性液体的液滴组成的无水乳液以及聚合技术而成为可能。无水乳液对于这种封装系统的开发至关重要，因为它们可以使专用液体保持纯净。这项工作解决了聚合物壳的组成如何影响胶囊的性能，即机械性能和气态二氧化碳的吸收。这项研究促进了复合材料领域的进展，并在能源储存和气体分离等关键领域得到应用。除了研究之外，该项目还将支持本科生和研究生的培训以及如何视频的开发。这些视频计划公开提供，并向新的研究人员展示如何使用科学仪器来表征聚合物基材料，从而更广泛地支持科学家和工程师的发展和培训。技术概述：计划研究的目标是开发制备具有活性液体（例如，离子液体和低共熔溶剂）和具有不同渗透性、稳定性和机械性能的聚合物复合外壳。这将通过利用非水乳液中的界面聚合来实现。烷基化氧化石墨烯（GO）纳米片将用作颗粒表面活性剂以稳定Pickering乳液，甲苯或辛烷将用作连续相，离子液体或深共熔溶剂将用作不连续相。目的1集中于使用遥爪低聚物作为单体制备具有不同渗透性和机械性能的胶囊壳，所述单体通过开环易位聚合（ROMP）、可逆加成断裂链转移（RAFT）聚合和自由基死端聚合（DEP）制备。在目标2中，胶囊壳的稳定性将通过并入动态共价键来调整;这将使得胶囊壳能够破坏或融合。在目标3中，通过使用反应性颗粒表面活性剂和硫醇-烯化学，将使胶囊壳厚度最小化并且使芯流体纯度最大化。将确定胶囊的组成、形态、热性能、渗透性和机械性能。与Burcu Gurkan教授的一项无资金支持的合作将揭示外壳成分与气态CO2渗透率之间的关系。 与乔治法尔教授的一项无资金支持的合作将支持使用显微操作技术对单个胶囊进行评估，产生力-位移曲线。科学研究得到了本科生和研究生研究人员的支持，以及如何视频（HTV）的补充，这些视频展示了用于表征软物质的技术的工作原理和实际考虑。该奖项反映了NSF的法定使命，并被认为是值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估的支持。

NON-TECHNICAL SUMMARY:Scientists and engineers continue to develop new materials with improved performance in applications such as batteries, water purification, gas uptake, and so on. These novel materials provide the foundation used to create new technologies that impact and improve nearly every facet of modern life. Unfortunately, some of the new materials, such as ionic liquids and eutectic solvents, are difficult to handle by themselves, and they require containment of some kind, limiting their use in practical systems. This research work addresses these current limitations by developing methods to prepare capsules with cores of the specialized liquid wrapped in polymer shells. This approach is made possible by the use of a water-free emulsion that is composed of droplets of the active liquid dispersed in an oil, coupled with polymerization techniques. The water-free emulsions are critical to the development of this encapsulation system, as they allow the specialized liquid to remain pure and unadulterated. The work addresses how the composition of the polymer shell impacts performance properties of the capsules, namely mechanical properties and the uptake of gaseous carbon dioxide. This research promotes progress in the areas of composite materials with applications in critical areas such as energy storage and gas separations. In addition to the research, this project will support the training of undergraduate and graduate students and development of How-To Videos. These videos are planned to be publicly available and to show new researchers how to use scientific instruments to characterize polymer-based materials, thereby supporting the development and training of scientists and engineers more broadly. TECHNICAL SUMMARY:The goal of the planned research is to develop methods to prepare capsules with cores of active liquids (e.g., ionic liquids and deep eutectic solvents) and polymer composite shells of varied permeability, stability, and mechanical properties. This will be accomplished by leveraging interfacial polymerizations in non-aqueous emulsions. Alkylated graphene oxide (GO) nanosheets will be used as particle surfactant to stabilizing Pickering emulsions, toluene or octane will be used as the continuous phase, and ionic liquid or deep eutectic solvent as the discontinuous phase. Aim 1 focuses on preparing capsule shells of varied permeability and mechanical properties using telechelic oligomers as monomers, as prepared by ring opening metathesis polymerization (ROMP), reversible-addition fragmentation-chain transfer (RAFT) polymerization, and radical dead-end polymerization (DEP). In Aim 2, the stability of the capsule shell will be tuned by incorporation of dynamic covalent bonds; this will enable destruction or fusion of the capsule shells. In Aim 3, the capsule shell thickness will be minimized and the core fluid purity maximized by using reactive particle surfactants and thiol-ene chemistry. The capsule composition, morphology, thermal properties, permeability, and mechanical properties will be established. An unfunded collaboration with Prof. Burcu Gurkan will reveal the relationship between shell composition and permeability to gaseous CO2. An unfunded collaboration with Prof. George Pharr will support evaluation of individual capsules using micromanipulation techniques, producing force-displacement profiles. The scientific research is complemented by support of undergraduate and graduate researchers, as well as How-To Videos (HTVs) which demonstrate working principles and practical considerations for techniques used to characterize soft matter..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.