Collaborative Research: Sub-Voxel Molecular Patterning of Actuators and Photonic Structures in 3-Dimensional Free-Forms

这笔赠款支持对宏观聚合物结构进行3D打印的研究，这些结构具有可以在亚微米尺度上定义的工程分子顺序。在任意形状因子的易印刷结构中，具有特殊光学和力学性能的分子工程结构可以改善许多应用领域。这些特性包括可以随周围环境变化的结构颜色，以及创造人造肌肉的能力，这些肌肉可以根据环境刺激产生机械功。控制可打印材料中的分子结构和组成是实现这些功能的关键因素。基础研究的进步可以使软机器人能够在3D打印结构中集成执行器和传感器。自感知驱动和光学报告变形状态的能力为软机器人开发新的控制策略提供了可能。这将是它们在未来医疗器械中潜在应用的关键，这些医疗器械用于微创手术和需要操纵易碎物体的工业应用。这项研究还将为本科生和研究生提供培训机会，他们将接触到具有活性软物质的制造业中的新兴概念。这个项目将控制立体平版印刷系统中液晶单体的表面锚定、磁中介排列和手性自组装之间的相互作用。单体的结构和组成对3D打印体素中手性向列序的影响将被理解为打印参数的函数。工艺-结构关系将被用来体素自由形状几何形状中的平面内和贯穿厚度的蓝图微结构。我们将探索分子图案化所能达到的分辨率的基本极限。这将被用来告知空间的光学和机械特性，以及它们对施加的刺激的敏感性。最终，这项研究设想了3D打印结构，能够通过耦合对光学特性的机械响应来变形并向观察者自我报告状态。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。

This grant supports research into the 3D printing of macroscopic polymeric structures with an engineered molecular order that can be defined at the sub-micrometer-scale. The molecularly engineered structures with unusual optical and mechanical properties in easily printed structures with arbitrary form factors could improve many application areas. These properties include structural color that can change in response to the surrounding environment and the ability to create artificial muscles that generate mechanical work from an ambient stimulus. Control of the molecular structure and composition in printable materials is the key enabler of these functionalities. Fundamental research advances can enable soft robots that integrate actuators and sensors within a 3D printed structure. The ability to self-sense actuation and optically report deformation state allows for the development of new control strategies in soft robots. This will be key to their potential applications in future medical devices for minimally invasive surgery and industrial applications that require manipulation of fragile objects. This research will also result in training opportunities for undergraduate and graduate students who will be exposed to emerging concepts in manufacturing with active soft matter. Outreach initiatives targeted at the K-12 levels will prioritize inclusion of traditionally underrepresented groups.This project will control the interplay between surface anchoring, magnetically-mediated alignment, and chiral self-assembly of liquid crystal monomers in a stereolithographic printing system. The effect of the monomer’s structure and composition on the chiral nematic order in 3D printed voxels will be understood as a function of the printing parameters. Process-structure relationships will be used to voxelate the blueprinted microstructure both in-plane and through-thickness in freeform geometries. Fundamental limits on the resolution at which the molecular patterning can be enforced will be explored. This will be used to inform the space of optical and mechanical properties, as well as their sensitivity to an applied stimulus. Ultimately, this study envisions 3D printed structures that are capable of morphing and self-reporting state to an observer via a coupling of the mechanical responses to the optical properties.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.