Polymeric Fibers with High Strength and High Toughness at Extreme Temperatures.

Developing strong and simultaneously tough polymeric materials with excellent thermal stability and mechanical performance even under extreme temperatures is truly a challenge. In a disruptive progress, we develop continuous polymeric yarns with a combination of high tensile strength of (1145 ± 44) MPa and ultra-high toughness of (350 ± 24) J/g and high thermomechanical properties from -196 °C to 200 °C. The comprehensive thermomechanical performance of this yarn surpasses that of previously developed polymeric materials and dragline spider silks. Our results demonstrate that the molecular structure of polyimide with the incorporation of flexible-rigid macromolecular, hierarchically spiral-oriented fibers, and high glass transition temperature (248 °C) are keys for the yarn's notable comprehensive performance in thermomechanical properties. Our materials are ideal for technical components exposed to high thermomechanical loadings, such as those encountered in spacecraft or automotive engineering for safety-critical applications. This article is protected by copyright. All rights reserved.