Photosensitive PEEK Ink Enables Digital Light Processing 3D Printed High-performance Small Architected-Plastics

Abstract: Polyetheretherketone (PEEK), as a semi-crystalline high-performance engineering plastic, has demonstrated good application prospects since its introduction. The ability of PEEK to be fabricated in complex architecture is a major limitation due to the inherent shortcomings of material extrusion 3D printing technology in terms of low resolution, low surface quality, and interlayer bonding. We propose a novel PEEK ink processing process based on digital light processing (DLP) 3D printing, which is based on high solid content PEEK ink to achieve green bodies with high accuracy, and one-step sintering to enhance the crystallinity of PEEK. We have investigated the processing mechanism of this process and constructed perfect process parameters in terms of mouldability, printing accuracy, material thermal properties, and PEEK crystallinity. Furthermore, the material and architecture performance of the proposed process was evaluated in terms of comprehensive thermal performance (including heat resistance of the substrate, thermal stability, surface energy after heat treatment, and coefficient of static friction and coefficient of kinetic friction), mechanical performance, and corrosion resistance (20 wt% hydrochloric acid, 20 wt% sodium hydroxide, 99 wt% acetone, and 99.5 wt% chloroform). The process is a bold extension of PEEK processing methods to utilize the properties of PEEK in more flexible and efficient applications.