Collaborative Research: A Scalable Processing Method to Produce Thermoplastic Nanofibers from Melt

聚合物纳米纤维可以在许多应用中产生重大的社会影响，包括水过滤，药物输送，能量存储以及用于汽车和航空航天领域的轻质复合材料。尽管具有重要的潜在应用，但生产纳米纤维的可扩展方法仍处于起步阶段。目前的方法，如众所周知的静电纺丝工艺，通常依赖于从溶液中加工聚合物，其中大量溶剂释放到环境中。该溶剂显著增加了原材料成本和生产单位的环境足迹，并要求采取极端的安全通风措施来保护员工。该奖项支持基础研究，以产生以无溶剂和工业规模化方法生产聚合物纳米纤维所需的知识。该方法适用于广泛的聚合物。 这项研究的结果将通过建立无溶剂和“绿色”清洁生产方法，影响先进制造业，从而影响美国经济。研究目标的实现将通过多学科的努力，在材料科学，化学工程，纤维加工和能量-物质耦合的专业知识的指导下。这一努力还将扩大代表性不足的学生团体在STEM领域的参与。目标是以环境可持续和可扩展的方式开发制造连续聚合物纳米纤维的科学和技术。为此，计划了一种新形式的熔体静电纺丝，其中聚合物熔体通过电磁辐射通电并通过静电场牵引。具有碳纳米管夹杂物的微纤维将用作碳纳米管前体。这项工作的智力意义部分在于试图发展新的理解耦合能量到开发纳米纤维所需的物质。利用微纤维的提议在智力上也很重要，是可扩展性的关键。微纤维中的纳米管将作为辐射的能量吸收剂，以提高射流的温度，调节其粘度并通过静电力帮助减小射流直径。研究小组将通过实验研究复合纤维对微波辐射的能量吸收。然后，该团队将开发基于物理的模型，以探索从微纤维形成纳米纤维。基于模型输出，该团队将开发处理纳米纤维的设置。该装置将允许真实的时间监测的形成，以获得更多的洞察力，以能量物质耦合。

Polymeric nanofibers can have major societal impacts in many applications including water filtration, drug delivery, energy storage, and light-weight composites for automotive and aerospace sectors. Despite significant potential applications, scalable methods to produce nanofibers are in their infancy. Current methods such as the well-known electrospinning process often rely on polymer processing from solutions in which a large quantity of solvent is released to the environment. The solvent significantly increases the cost of raw materials and the environmental footprint of the production units, and demands extreme measures for safe ventilation to protect the workforce. This award supports fundamental research to generate the knowledge required to produce polymeric nanofibers in a solvent-free and industrially scalable method. The method is applicable to a wide range of polymers. The results from this research will impact advanced manufacturing and, hence, the U.S. economy, by establishing solvent-free and thus "green" nanofiber production methods. The fulfillment of the research goal will be through a multidisciplinary effort, guided by expertise in material science, chemical engineering, fiber processing and energy-matter coupling. This effort will also broaden the participation of underrepresented student groups in STEM fields. The goal is to develop the science and technology of manufacturing continuous polymeric nanofibers in an environmentally sustainable and scalable fashion. To this end, a novel form of melt electrospinning, where polymer melts are energized via electromagnetic radiation and pulled by electrostatic fields is planned. Microfibers with carbon nanotube inclusions will be utilized as nanofiber precursors. The intellectual significance of this work partly lies in attempts to develop new understanding for coupling energy to matter required to develop nanofibers. The proposition to utilize microfibers is also intellectually significant and is a key to scalability. The nanotubes in microfibers will serve as energy absorbers from radiation to raise the temperature of the jet, regulate its viscosity and assist with reducing the jet diameter via electrostatic forces. The research team will experimentally study the energy absorption by composite fibers from microwave radiation. The team will then develop physics-based models to explore the formation of nanofibers from microfibers. Based on model output, the team will develop the setup to process nanofibers. The setup will allow for real time monitoring of the nanofiber formation to obtain more insight into energy-matter couplings.