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、可扩展的制造纳米颗粒的方法提供了资金，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。表面张力驱动流体的不稳定性，即所谓的高原-瑞利毛细不稳定性，它导致逐渐减弱的水射流破碎成液滴。这里利用相同的基本现象将嵌入纤维内的所选材料的完整圆柱形纳米线的延伸长度转化为彼此隔离的球形纳米颗粒的项链。该项目将研究该工艺可产生的最小粒度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化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子结构的纳米颗粒提供一条途径，这仍然是纳米尺度的基本技术挑战。这种跨学科的努力的智力价值源于解决这一根本性的挑战，通过结合热诱导纤维拉伸和流体动力学，这最初似乎无关。该项目还为纳米尺度的流体动力学基础研究提供了一种新的物理实现。该项目的更广泛影响在于这些纳米结构的广泛应用。例子包括从生物可降解聚合物颗粒中控制释放药物，到具有新颖光学特性的油漆和涂料。此外，还将开展多方面的宣传计划，包括为橙子县（佛罗里达）学校举办为期一天的夏季活动，题为“自己制作纤维日”，让高中生了解纤维生产的奇迹。

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.