Collaborative Research: Designer Microstructures by Additive Manufacturing of Functional Emulsions

功能乳液是一种新兴的材料结构，用于创建柔软且可弹性变形的高功能弹性体复合材料。然而，缺乏控制乳液中复合材料的局部组成和微观结构的技术，这些技术最终控制着固化的弹性体复合材料的材料性能和性能。该奖项支持基础研究，以开发一种添加剂制造技术来控制乳液中的液体夹杂微结构，以实现弹性体复合材料中前所未有的热、电和机械功能的组合。通过开发材料和制造知识来编程夹杂微结构，新一代功能材料的复合材料架构中的新范例成为可能，从而在电子和机器人领域产生新的应用，从而使美国经济和社会受益。通过团队成员制作的《研究背后》视频集和面向9-12年级学生的制造车间，该项目为添加剂制造和软机器人新兴领域的未来领导者提供灵感和培训。该项目建立了可固化成复杂几何形状的弹性体复合材料的添加制造功能乳液的加工-结构-性能关系。这是通过创建模型乳液油墨、加工方法和现场过程监控来实现的，以确定材料组成和印刷条件如何影响材料微结构。这些基本的工艺和材料洞察力与乳液挤出的新理论模型相结合，以预测整个制造部件中液相夹杂物的微观结构。液态金属包裹体和甘油液态包裹体表现出明显不同的基本性质，但两者在软物质工程领域都具有广泛的适用性。与形状和尺寸固定的刚性炭黑、铜或二氧化硅颗粒填料相比，通过直接墨写工艺按需控制液体夹杂物形态为制造弹性体复合材料提供了一种新的有效方法。在制造过程中，积极地定制局部材料成分和液体夹杂微观结构，以控制弹性体复合材料的电、热和机械性能。通过将油墨特性和过程控制与工具设计和建模相结合，这项工作为创建可扩展的加工乳剂制造策略提供了新的基础知识。这导致了具有可编程工艺-结构-性能关系的新型模型材料系统，以确定多组分软物质的基于物理的特性。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。

Functional emulsions are an emerging material architecture for creating highly functional elastomer composites that are soft and elastically deformable. However, techniques to control local composition and microstructure of the composite material in emulsions, which ultimately govern material properties and performance of the cured elastomer composite, are lacking. This award supports fundamental research to develop an additive manufacturing technique to control liquid inclusion microstructure in emulsions to achieve unprecedented combinations of thermal, electrical, and mechanical functionalities in elastomer composites. By developing the material and manufacturing knowledge to program inclusion microstructure, new paradigms in composite architecture for next generation functional materials are enabled leading to new applications in electronics and robotics, which benefits the U.S. economy and society. Through a collection of ‘behind the research’ videos generated by team members and a manufacturing workshop for 9-12 grade students, the project provides inspiration and training for future leaders in the emerging fields of additive manufacturing and soft robotics.This project establishes the processing-structure-property relationships of additively manufactured functional emulsions that can be cured into an elastomer composite of complex geometry. This is achieved by creating model emulsion inks, processing methods, and in-situ process monitoring to determine how material composition and printing conditions influence material microstructure. These fundamental processing and material insights are combined with new theoretical models for emulsion extrusion to predict the microstructure of liquid phase inclusions throughout a manufactured part. Liquid metal and glycerol liquid phase inclusions are examined as they present distinctly different fundamental properties, but both offer broad applicability in the field of soft matter engineering. In contrast to rigid carbon black, copper, or silica particle fillers that have fixed shape and size, the on-demand control of liquid inclusion morphology via direct ink write processing provides a new and efficient method to manufacture elastomeric composites. During the manufacturing process, the local material composition and liquid inclusion microstructure are actively tailored to control the electrical, thermal, and mechanical properties of elastomeric composites. By combining printing ink properties and process control with tool design and modeling this work provides new fundamental knowledge to create scalable manufacturing strategies for processing emulsions. This leads to novel model material systems with programmable processing-structure-property relationships to determine physics-based properties of multi-component 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.