STTR Phase II: High-Strength Low-Cost Fiber Via Multi-Component Nanofiber (MCN) Spinning

这个小型企业技术转移研究（STTR）二期项目的总体目标是开发一种多组分熔融纺丝方法，使用标准的低成本聚合物生产新的高性能纤维系列。新的高强度和/或高模量聚合物纤维将使用先进的商业纺纱技术和一套创新的、以前未开发的纺纱工艺参数来制造。由此产生的新纤维在性能上可与目前市场上的其他高性能纤维相媲美，但成本要低得多。纺纱实验将在实验室/实验规模和中试线水平进行。将对实验纤维纺丝线进行修改，以使纤维生产保持一致。将使用各种工具（聚焦离子束、扫描和透射电子显微镜、x射线、拉伸、侧向压缩、密度、差示扫描量热法和动态力学分析）对生产的纤维进行表征，以了解导致强度和/或刚度提高的新机制。使这些机构的纺丝条件将被优化，以满足目标强度和/或刚度目标。还将研究引入抗紫外线添加剂和/或其他特定用途成分的可能性，以及对性能的任何相应影响。该项目的更广泛影响/商业潜力是基于实现新纤维的性能目标，其强度为15 gf/旦尼尔和/或初始模量为400 gf/旦尼尔或更高。考虑到预期的低成本大批量生产能力，这些新纤维的成本将接近标准高强度工业纤维（约7美元/磅），而特种高性能纤维（如芳纶和高性能聚乙烯（HPPE））的典型成本为20美元/磅。新纤维产品的性能将高于目前的高强工业纤维（HT聚酯和尼龙），但低于目前的特种高性能纤维（芳纶、HPPE）。这些纤维的成本降低将导致各种应用的成本降低，这将有利于社会（例如，通过防切割服装和其他安全/保护装置的更大扩散）。除了这些经济效益外，所提出的工作将提供纳米级纤维的广泛表征，这将有助于科学地理解聚合物纤维的结构和行为。

This Small Business Technology Transfer Research (STTR) Phase II project has the overall objective of developing a multi-component melt spinning approach to produce a new family of high performance fibers using standard low-cost polymers. The new high-strength and/or high-modulus polymeric fiber is to be made using cutting-edge but commercially available spinning technology and an innovative and previously unexplored set of spinning process parameters. The resulting new fiber will be comparable in performance to other high-performance fibers on the market today, but will cost significantly less. Spinning experiments will be conducted at both the laboratory/bench scale, and at the pilot line level. Experimental fiber spinning lines will be modified to enable consistent fiber manufacturing. Produced fibers will be characterized using a variety of tools (focused ion beam, scanning and transmission electron microscopy, X-ray, tensile, lateral compression, density, differential scanning calorimetry, and dynamic mechanical analysis) to understand the new mechanisms that lead to improved strength and/or stiffness. The spinning conditions which enable these mechanisms will be optimized to meet target strength and/or stiffness goals. The possibility of introducing UV-resistant additives and/or other application-specific components, and any corresponding effects on performance, will also be studied. The broader impact/commercial potential of this project is based on achieving a performance goal for the new fibers of tenacity 15 gf/denier and/or an initial modulus of 400 gf/denier or greater. Given the anticipated capability for low-cost high-volume production, these new fibers will have a cost approaching that of standard high tenacity industrial fibers (~ $7/lb) as compared to the typical $20/lb for specialty high performance fibers such as aramids and high-performance polyethylene (HPPE). The new fiber products will be designed to have a performance above current high-tenacity industrial fibers (HT polyester and nylon) but below current specialty high-performance fibers (aramids, HPPE). The reduced cost for these fibers will result in lower costs over a variety of applications, which will benefit society (for example, by the greater proliferation of cut-resistant apparel and other safety/protective devices). In addition to these economic benefits, the proposed work will provide extensive characterization of nano-scale fibers that will contribute to the scientific understanding of polymeric fiber structure and behavior.