GOALI: Melt Processable Polymer Nanocomposites for Low Friction and Low Wear Applications

几乎每台机器都至少有一个性能关键的滑动界面。接头、衬套和轴承必须在低摩擦和低磨损的情况下可靠地运行，才能使机器移动并执行所需的任务。据估计，仅在美国，每年因摩擦和磨损造成的损失就超过5000亿美元。开发用于可持续滑动应用的新材料具有广泛和实质性的需求。该奖项支持开发一种超低磨损聚合物系统，该系统可以通过注塑和其他理想的制造技术来制造。杜邦和利哈伊大学之间的关系将使这种材料的技术、工业和商业发展成为可能。最后，尽管有明显的影响，但美国在摩擦学(摩擦和磨损)方面的教育不足，落后于许多国家。这个项目通过增加社会各阶层对摩擦学的教育、接触和兴趣来应对这些挑战，包括：1)动手K-12摩擦学实验，2)将摩擦学纳入LeHigh工程课程，3)LeHigh和杜邦实验室的研究生和本科生培训，以及4)为工业工程师提供研讨会和在线资源。这个学术联系(GOALI)计划奖支持LeHigh大学和杜邦的研究人员之间的合作，开发和研究超低磨损熔融可加工氟聚合物复合材料，目标1)了解摩擦学性能与材料结构、组成、2)对超低磨损全氟聚合物滑动磨损中复杂的摩擦机械和摩擦化学过程有了完整的机械理解。这一智力优势源于对含5%纳米填料的全氟聚合物(例如，全氟烷氧基--一种可熔融加工的含氟聚合物)的磨损性能大幅提高(10,000倍)的机械理解。耦合的、多尺度的、物理、材料、机械和化学机制在很大程度上是难以捉摸的。假设的机理包括氟聚合物的摩擦化学链断裂，导致转移膜共价连接到对比物表面，以及形成虚拟交联物(键合到纳米填料上的多个端基)以稳定聚合物的磨损表面。这项研究将使用学生建造的仪器来直接验证假设的机制，即原位摩擦化学反应产物改变其他惰性氟聚合物的性质。一种多方面的表征方法将系统地检验这些假设，并发现这些材料的新机制，最终可能使材料的科学设计成为可能。

Nearly every machine has at least one performance-critical sliding interface. Joints, bushings and bearings must operate reliably with low friction and low wear in order for the machine to move and perform desired tasks. The costs of friction and wear are estimated to be greater than $500 billion per year in the U.S. alone. There is a broad and substantial need to develop new materials for sustainable sliding applications. This award supports the development of an ultralow-wearing polymer system that can be manufactured by injection molding and other desirable manufacturing techniques. The relationship between DuPont and Lehigh University will enable the technical, industrial and commercial development of this material. Finally, despite the obvious impacts, education on tribology (friction and wear) is insufficient in the US, falling behind many countries. This project addresses these challenges through increased education, exposure and interest in tribology at all levels of society, including: 1) hands-on K-12 tribology experiments, 2) incorporating tribology in Lehigh engineering curriculum, 3) graduate and undergraduate student training at Lehigh and DuPont labs, and 4) provide industry engineers with seminars and online resources.This Grant Opportunity for Academic Liaison with Industry (GOALI) Program award supports a collaboration among researchers at Lehigh University and DuPont, to develop and study ultralow-wear melt processable fluoropolymer composites with goals of 1) understanding the relationship between tribological performance and material structure, composition, processing and operating conditions and 2) developing a complete mechanistic understanding of the complex tribomechanical and tribochemical processes in the sliding wear of ultralow wear perfluoropolymers. The intellectual merit is rooted in a mechanistic understanding of the substantial (10,000 x) improvement in wear performance of perfluoropolymers (e.g. perfluoroalkoxy -a melt processable fluoropolymer) with 5 vol percent nanofillers. The coupled, multi-scale, physical, material, mechanical and chemical mechanisms have been largely elusive. The hypothesized mechanism includes tribochemical chain scission of the fluoropolymer resulting in a transfer film that is covalently attached to the surface of a countersample as well as formation of virtual crosslinks (multiple end groups bonded to the nanofiller) that stabilize the wear surface of the polymer. The research will use student-built instruments to directly validate the hypothesized mechanism that in situ tribochemical reaction products alter the properties of otherwise inert fluoropolymers. A multi-faceted characterization approach will systematically test the hypotheses and discover new mechanisms of these materials that could, ultimately, enable science-based design of materials.