Invited Speaker

Abstract: Polyetherimide (PEI), polyetheretherketone (PEEK), polysulfone (PSU), and other thermoplastic resins are classified as special engineering plastics due to their excellent mechanical properties, wear resistance, heat resistance, and long-term service temperatures exceeding 150°C, which have wide applications in aerospace, automotive, electronics, and other demanding fields. To further enhance the overall performance of these special engineering plastics, short fibers are commonly incorporated. Currently, the primary methods for preparing short fiber-reinforced composites based on special engineering plastics are melt blending extrusion followed by injection molding. However, a significant limitation of this conventional process is the resulting short retained fiber length in the composites, which severely compromises their mechanical properties. To address this issue, the applicant systematically investigated the influence of preparation process parameters on the mesostructure of the composites. This led to the proposal of a novel composite preparation technology designed to achieve high retained fiber length. Based on this technology, short fiber-reinforced PEI composites were developed, demonstrating a 50% increase in tensile strength and Young’s modulus compared to traditional composites produced via extrusion and injection molding. Furthermore, the mechanical properties—including tensile and flexural behavior—and service performance of injection-molded PEI composites under various temperature environments were systematically investigated. This work revealed the interfacial failure mechanisms of SCF/PEI at different temperatures. The potential of these injection-molded PEI composites for use as load-bearing components was explored. Additionally, their friction and wear characteristics under service conditions, such as dry contact, water lubrication, and oil lubrication, were comprehensively studied. The high-performance injection-molded composites developed have found successful application in aerospace, defense and other fields.

Keywords: Thermoplastic composite, injecting-molding, short fiber, strength, wear

Biography: Dr. Li is a Professor at College of Aerospace Engineering, Chongqing University. He has worked in the research fields of polymer matrix composites for aerospace, smart composites, composite mechanics, and published more than 170 papers in peer-reviewed journals, including 120 first author and/or corresponding author papers. His research work received good attention by the international community, his total citations based on the Scopus is more than 10000 times with an h-index 51. He also holds more than 10 patents, and published 5 book chapters. He is currently the Academic Editor and Editorial Board Member of Nano Materials Science, Member of Nano-Micro Composites Committee, Smart Composites Committee, Composites Health Monitoring Committee of Chinese Society for Composites. He has been listed in the World’s Top 2% Scientists lists by Stanford University on Elsevier in Career-long Impact list since 2023 and Single-year Impact since 2021.