An Integrated Experimental and Computational Platform for Discovery and Processing of Functional Nano-Emulsions

通过控制加工历史合理设计新材料并设计其性能的能力，将使合成出具有独特性能且易于制造的全新材料类别成为可能。这项研究旨在通过操纵由纳米颗粒和聚合物纳米乳液组成的简单系统来开发这些技术，使其成为具有可调机械和相关性能的各种结构形式。由聚合物、粒子、乳液和表面活性剂制成的软材料被广泛应用于一系列新兴的和社会相关的应用中，包括医疗和能源技术，以及人体和电子领域之间的接口。因此，这可能会打开新的制造模式，帮助推动经济中的新领域，并促进我们在材料设计方面的知识。软材料的发现和加工是独一无二的。对于每一种应用，都需要一套材料特性：弹性模量、屈服应力、屈服应变、渗透率、导电率等，材料选择范围很广。这项研究着眼于通过利用外场进行结构的组合设计和制造来减少可能材料的设计空间。这项研究将开发生成材料设计空间的方法，以及从生成的数据高效推导结构的方法。在制造过程中，利用与聚合物复合材料的组件密切相互作用的外场在微尺度上排列组件，以产生新的机械结构。这种数据驱动的材料设计和加工是材料选择和结构开发的新方法和新范式。与这项研究相辅相成的是，开发了一款视频游戏，扩大了公众对软材料及其特性的理解，并将公开发布。新的软材料和生物材料的发现在很大程度上是由反复试验推动的，许多经验和一些理论结构-性质关系促进了这一过程。当这些关系已知时，可以通过瞄准适当的微结构(例如，结晶的、玻璃的、分形的、各向异性的)来合成具有期望功能的材料。此外，许多软物质材料被淬火以组装成不是最低能态的结构，并且强烈地依赖于加工历史。因为软材料是多功能的，应用广泛：生物医学研究和技术，石油和天然气勘探和运营，消费者护理产品，以及整个农业和食品工业，都需要高度定制的材料来满足特定应用的需求。这项研究将开发设计多功能软材料所需的实验和计算工具，这些材料由纳米乳液构建，纳米乳液是由悬浮在水中的各种油组成的纳米级液滴。通过改变悬浮液中液滴和添加剂的化学组成，可以合成具有良好颗粒间相互作用的纳米乳液。通过改变温度、盐度、外加磁场和流场的时间，可以诱导纳米乳液聚集成具有广泛不同形态特征的凝胶结构。这项工作的一个具体目的是了解和控制如何利用工艺历史来对这些纳米复合材料的微结构和由此产生的性能进行精细控制。这将通过进行详细的模拟来实现，这些模拟探索了广阔的、可实验访问的参数空间，然后利用机器学习工具选择富有成效的纳米乳液和加工方法来产生新型软材料。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The ability to design new materials rationally and engineer their properties through control of processing history will enable the synthesis of whole new classes of materials with unique properties that are easily manufacturable. This research looks to develop those techniques through the manipulation of a simple system consisting of nanoparticles and polymer nano-emulsions into a wide variety of structural forms with tuned mechanical and related properties. Soft materials built from polymers, particles, emulsions, and surfactants are employed in a broad array of emerging and societally relevant applications including medical and energy technologies, and the interface between the human body and the electronic domain. As such, this could open new manufacturing paradigms assisting driving new areas in the economy and advancing our knowledge in materials design. The discovery and processing of soft materials is idiosyncratic. For each application, a set of material properties: elastic modulus, yield stress, yield strain, permeability, conductivity, among others is needed and the materials choices are vast. This research looks to reducing the design space of possible materials through the combined design and fabrication of structures utilizing external fields. The research will develop approaches to generating the materials design space and the means to efficiently derive structures from the generated data. The use of external fields which interact intimately with the components of the polymer composite to arrange the components at the microscale during fabrication to produce new mechanical structures. This data-driven material design and processing is a new approach and paradigm to materials choice and structure development. The research is complemented by the development of a video game broadening the public understanding of soft materials and their properties which will be made publicly available. The discovery of new soft and biomaterials is driven largely by trial and error facilitated by many empirical and a few theoretical structure-property relations. When such relations are known, materials with a desired functionality can be synthesized by targeting the appropriate microstructure (e.g. crystalline, glassy, fractal, anisotropic). Moreover, many soft matter materials are quenched to assemble into structures which are not the lowest energy state and depend strongly on processing history. Because soft materials are multifunctional and applied broadly: to biomedical research and technologies, for oil and gas exploration and operations, in consumer care products, and throughout agriculture and the food industry, highly tailored materials are required to meet application specific needs. This research will develop the experimental and computational tools needed for the design multifunctional soft materials built from nano-emulsions, nano-scale droplets composed of a diverse array of oils suspended in water. Through variation of chemical composition of the droplets and the additives in the suspending solvent, nano-emulsions with well defined inter-particle interactions can be synthesized. By varying in time the temperature, salinity, applied magnetic fields, and flow fields, the nano-emulsions can be induced to aggregate into a gelled structure with a wide range of different morphological characteristics. A specific aim of this work is to understand and control how processing history can be used to exert fine control over this micro-structure and resulting properties of these nano-composites. This will be achieved by performing detailed simulations that explore the vast, experimentally accessible parameter space, and then utilizing machine learning tools to select fruitful nano-emulsions and processing methods to yield novel soft materials.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.