Scalable Manufacturing of Size-controllable Structured Nanoparticles via Capillary Instabilities in Multimaterial Fibers

这项拨款为研究一种新颖的、可扩展的纳米颗粒制造方法提供了资金，该方法以所需材料的延伸纤维为起点。这个过程依赖于每天从滴水的水龙头中看到的同样的不稳定性。表面张力导致流体不稳定，即所谓的高原-瑞利毛细管不稳定，这导致逐渐减少的水射流破裂成水滴。这里利用同样的基本现象，将所选材料的完整圆柱形纳米线的延伸长度嵌入纤维中，转化为彼此隔离的球形纳米粒子项链。该项目将研究该工艺可生产的最小颗粒尺寸以及与该工艺兼容的材料。将探索各种材料，从软玻璃到生物相容性聚合物。此外，该项目将为数字化设计结构纳米颗粒的内部结构奠定基础。这种方法将为大规模生产具有复杂亚结构的纳米粒子提供一条途径，这一任务仍然是纳米尺度上的一个基本技术挑战。这种跨学科努力的智力价值源于通过结合热诱导纤维拉伸和流体动力学来解决这一基本挑战，这两者最初看起来是无关的。该项目还为纳米尺度流体动力学的基础研究提供了一种新的物理实现。这个项目更广泛的影响在于这些纳米结构的广泛应用。例如，从可生物降解的聚合物颗粒中控制药物释放到具有新型光学特性的油漆和涂层中。此外，还将开展一项多方面的推广计划，包括为佛罗里达州奥兰治县（Orange County）的学校举办为期一天的夏季活动，名为“自制纤维日”（Make Your Own Fiber Day），这将使高中生了解纤维生产的奇妙之处。

This grant provides funds for the investigation of a novel, scalable approach to fabricating nanoparticles that takes as its starting point extended fibers of a desired material. The process relies on the same instability that is witnessed every day from a dripping faucet. Surface tension drives the fluid instability, the so-called Plateau-Rayleigh capillary instability, which causes a waning jet of water to break up into droplets. The same basic phenomenon is utilized here to transform extended lengths of intact cylindrical nanowires of the material of choice embedded inside a fiber into necklaces of spherical nanoparticles held isolated from each other. The project will investigate the smallest particle size that could be produced by this process and the materials compatible with such a procedure. A variety of materials will be explored, ranging from soft glasses to biocompatible polymers. In addition, this project will lay the foundations for digitally designing the internal architecture of structured nanoparticles. This methodology will provide a pathway to large-scale production of nanoparticles with sophisticated sub-structure, a task that remains a fundamental technological challenge at the nano-scale. The intellectual merit of this interdisciplinary effort stems from addressing this fundamental challenge by combining heat-induced fiber drawing and fluid dynamics, which initially appear unrelated. The project also provides a new physical implementation for fundamental studies of fluid dynamics at the nano-scale. The broader impact of this project lies in the wide range of applications for these nanostructures. Examples include the controlled-release of drugs from biodegradable polymer particles, to paints and coatings with novel optical properties. In addition, a multi-faceted outreach plan will be carried out, including daylong summer events for Orange County (Florida) schools entitled "Make Your Own Fiber Day", which will bring high school students to the wonders of fiber production.