Influence of Small Molecule Additives on Gemini Dicarboxylate Lyotropic Liquid Crystal Structure and Stability

小分子添加剂对Gemini二羧酸盐溶致液晶结构和稳定性的影响

• 批准号: 1507711
• 负责人: Mahesh Mahanthappa
• 金额: $ 44.19万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2016-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1507711&HistoricalAwards=false
• 关键词: Influence; Small; Molecule; Additives; Gemini

In this project funded by the Macromolecular, Supramolecular and Nanochemistry Program of the NSF Chemistry Division, Mahesh Mahanthappa of the University of Wisconsin-Madison is studying how small molecule surfactants, in which a water-soluble headgroup is attached to a water-insoluble tail, self-assemble in water. At high surfactant concentrations in water, these molecules spontaneously form a variety of structurally periodic soft materials known as liquid crystals. Certain liquid crystal structures are particularly useful in practical technical applications, yet these structures are difficult to access and their properties are limited. This project addresses these problems by investigating how adding salts and oils to water/surfactant mixtures enables the formation of these useful liquid crystals. A subset of the resulting materials may find long term application in fields such as therapeutic drug delivery. Another aspect of this project focuses on converting these liquid crystals into useful polymer membranes for energy efficient separations of complex chemical mixtures and for the generation and use of renewable fuels derived from solar energy. The broader impacts of this work include mentoring graduate and undergraduate students in research projects at the boundary between fundamental science and technological innovation, which will is expected to lead to useful materials for future healthcare and renewable energy applications.This project investigates how small molecule additives control the water concentration-dependent self-assembly of gemini ("twin tail") dicarboxylate surfactants to form lyotropic liquid crystals (LLCs). A special emphasis in this project is placed on identifying methods for stabilizing network phase LLCs with interwoven, periodic, and percolating 3D-networks of aqueous and hydrophobic domains. The influence of various hydrophilic, hydrophobic, and amphiphilic molecular additives on LLC structure formation and stability are being evaluated by polarized light microscopy and temperature-dependent X-ray scattering. These studies are informing the development of mixtures of reactive surfactants and molecular additives that spontaneously form network phase LLCs for subsequent polymerization into functional, nanoporous polymer membranes. Professor Mahanthappa is translating related research results into public outreach demonstrations that showcase the utility of simple "soaps" in hydraulic fracturing applications ("fracking") for oil and gas recovery, to engage the public in broader discussions of energy harvesting technologies and global energy demands.

在这个由 NSF 化学部大分子、超分子和纳米化学项目资助的项目中，威斯康星大学麦迪逊分校的 Mahesh Mahanthappa 正在研究小分子表面活性剂（其中水溶性头基连接到水不溶性尾部）如何在水中自组装。在水中表面活性剂浓度较高时，这些分子会自发形成各种结构周期性软材料，称为液晶。某些液晶结构在实际技术应用中特别有用，但这些结构难以获得且其性能受到限制。该项目通过研究如何在水/表面活性剂混合物中添加盐和油来形成这些有用的液晶，从而解决这些问题。所得材料的一部分可能会在治疗药物输送等领域得到长期应用。该项目的另一个方面侧重于将这些液晶转化为有用的聚合物膜，用于复杂化学混合物的节能分离以及产生和使用源自太阳能的可再生燃料。这项工作的更广泛影响包括指导研究生和本科生参与基础科学和技术创新之间的研究项目，预计这将为未来的医疗保健和可再生能源应用带来有用的材料。该项目研究小分子添加剂如何控制Gemini（“双尾”）二羧酸盐表面活性剂的水浓度依赖性自组装形成溶致液晶（LLC）。该项目的特别重点是确定稳定具有交织、周期性和渗透的水性和疏水性 3D 网络的网络相 LLC 的方法。通过偏光显微镜和温度依赖性 X 射线散射评估各种亲水性、疏水性和两亲性分子添加剂对 LLC 结构形成和稳定性的影响。这些研究为开发反应性表面活性剂和分子添加剂的混合物提供了信息，这些混合物可以自发​​形成网络相 LLC，以便随后聚合成功能性纳米多孔聚合物膜。 Mahanthappa 教授正在将相关研究成果转化为公共宣传演示，展示简单“肥皂”在石油和天然气回收的水力压裂应用（“水力压裂”）中的效用，让公众参与更广泛的能量收集技术和全球能源需求讨论。