DMREF: Collaborative Research: Polymeric Composites and Foams Based on Two Dimensional Surfactants

混合不同材料（如塑料、颗粒和溶剂）的挑战是阻碍具有新性能或改进性能的功能材料未来发展的主要因素之一。一个突出的例子是石墨烯基材料，石墨烯？由于缺乏与其他材料的相容性，石墨烯片往往会聚集在一起并堆叠，因此，高强度、高表面积和高导电性的非凡组合尚未得到充分利用。氮化硼片是另一个受同样问题限制的有前途的材料的例子。该项目试图克服这一障碍，利用两种不混溶溶剂之间的高能界面，迫使堆叠的石墨烯片剥离和扩散。对石墨烯和氮化硼表面活性的控制物理原理的理解将被应用于形成乳剂，作为合成具有优化机械和电气性能的石墨烯或氮化硼增强的泡沫状材料的前体。这些增强聚合物材料有潜力被用作强而轻的结构材料、电容器和电池的电极、柔性电子产品的衬底、导电、高表面积催化剂支撑和高吸收材料。该项目还将带来社会效益，因为它是建立在“化学奇才计划”基础上的推广活动，该计划的目标是学习科学探究的中学生。该项目旨在鼓励来自弱势群体的学生在STEM领域进行高等教育和职业发展。化学和物理上不同的物质如聚合物链、胶体颗粒和溶剂的混合是阻碍功能材料未来发展的主要因素之一。一个突出的例子是石墨烯基聚合物材料，石墨烯？相容性/溶解度的缺乏通常是通过牺牲其优越的电学、热学和机械性能的方法来克服的，从而使复合材料在未来的发展中不那么有吸引力。该项目试图克服这一障碍，利用两种不混溶溶剂之间的高能界面，迫使堆叠的石墨烯片剥离和扩散。降低系统的总自由能会推动薄片的重新排列。本研究的重点是建立一个统一的理论、计算和实验框架来描述二维材料在液/液界面的行为。该方法是多尺度的，从原子维度到介观维度。以石墨烯和氮化硼为例，这项工作将揭示溶剂对和反应条件的一般选择原则，从而实现使用二维薄片作为表面活性剂的新概念。对石墨烯和氮化硼表面活性的控制物理原理的理解将应用于形成乳剂，作为合成石墨烯或氮化硼增强泡沫状材料的前体。这些复合泡沫材料的理论和计算模型旨在设计具有最佳力学和电学性能的材料。这些设计工具将通过纳米和中尺度的实验研究进行测试和校准。最终，这项工作将概述具有定制性能的纳米结构、多功能、二维表面活性剂增强聚合物复合材料的设计原则，使材料的开发在一小部分时间内完成，而这将需要单独的试验和错误方法。增强聚合物材料有潜力被用作强而轻的结构材料、电容器和电池的电极、柔性电子产品的衬底、导电、高表面积催化剂支撑和超吸收材料。该项目还将带来社会效益，因为它是建立在“化学奇才计划”基础上的推广活动，该计划的目标是学习科学探究的中学生。该项目旨在鼓励来自弱势群体的学生在STEM领域进行高等教育和职业发展。

The challenge of mixing different materials such as plastics, particles, and solvents is one of the major factors hindering future advances in the development of functional materials with new or improved properties. A prominent example of this are graphene-based materials, where graphene?s extraordinary combination of high strength, surface area, and conductivity cannot yet be fully utilized as graphene sheets tend to clump together and stack due to a lack of compatibility with other materials. Boron nitride sheets are another example of a promising material limited by the same problem. This project attempts to overcome this obstacle by utilizing the high-energy interface between two immiscible solvents to force stacked graphene sheets to exfoliate and spread. The understanding of governing physical principles of surface activity of graphene and boron nitride produced by this activity will be applied to form emulsions that serve as precursors for the synthesis of foam-like materials reinforced with graphene or boron nitride with optimized mechanical and electrical properties. These reinforced polymeric materials have the potential to be used as strong and lightweight structural materials, electrodes in capacitors and batteries, substrates for flexible electronics, electrically conductive, high surface area catalyst supports, and super-absorbent materials. The project will also be of societal benefit as a result of outreach activities built on the Chemistry Wizards Program designed to target middle school children learning about scientific inquiry. The program aims to spur students from underrepresented populations to pursue post-secondary study and careers in STEM fields.Mixing of chemically and physically different species such as polymer chains, colloidal particles, and solvents is one of the major factors hindering future advances in the development of functional materials. A prominent example of this are graphene based polymeric materials, where graphene?s lack of compatibility/solubility is commonly overcome by approaches that compromise its superior electrical, thermal, and mechanical properties and make the composite materials less attractive for future development. This project attempts to overcome this obstacle by utilizing the high-energy interface between two immiscible solvents to force stacked graphene sheets to exfoliate and spread. Lowering the overall free energy of the system drives this rearrangement of sheets. This research is centered on the development of a unifying theoretical, computational and experimental framework to describe the behavior of two-dimensional materials at the liquid/liquid interface. The approach is multi-scale, reaching from the atomic to mesoscopic dimensions. Using graphene and boron nitride as examples, this work will reveal general selection principles for solvent pairs and reaction conditions for which the novel concept of using two-dimensional sheets as surfactants can be realized. The understanding of the governing physical principles of surface activity of graphene and boron nitride will be applied to form emulsions that serve as precursors for the synthesis of foam-like materials reinforced with graphene or boron nitride. The developed theoretical and computational models of these composite foams aim at the design of materials with optimized mechanical and electrical properties. These design tools will be tested and calibrated through experimental studies at nano- and meso-length scales. Ultimately, the work will outline design principles for nanostructured, multifunctional, two-dimensional surfactant-reinforced polymeric composites with tailored properties, enabling material development in a fraction of the time that would be required by a trial and error approach alone. The reinforced polymeric materials have the potential to be used as strong and lightweight structural materials, electrodes in capacitors and batteries, substrates for flexible electronics, electrically conductive, high surface area catalyst supports, and super-absorbent materials. The project will also be of societal benefit as a result of outreach activities built on the Chemistry Wizards Program designed to target middle school children learning about scientific inquiry. The program aims to spur students from underrepresented populations to pursue post-secondary study and careers in STEM fields.