Broad-spectrum chromaticity and high color fastness of polyimide fibers via intrinsic coloration

Intrinsic coloration method of PI fiber is achieved by copolymerizing chromophore. • A broad-spectrum chromatic PI fiber library is constructed. • Chromatic PI fibers exhibit high colorfastness against extreme environment. • Intrinsic coloration method can be extended to conventional PI fibers. Due to the exceptional thermal stability, radiation resistance, and mechanical properties, polyimide (PI) fibers are widely used in various extreme environments. However, the intrinsic monochromatic golden hue and chemically inert surface of PI fiber give rise to a natural barrier to dyeing and low color fastness. Herein, a facile and transformative intrinsic coloration strategy for the dyeing of PI fibers is proposed by directly incorporating a perylene-based chromophore monomer into the backbone of PI. By tuning the concentration and categories of perylene derivatives, various intrinsic colors of PI fibers are afforded, constructing a diverse chromatic PI fiber library with a broad color gamut (spanning from warm tones to slate-grey). Significantly, the strategy successfully overcomes the long-standing trade-off between dyeing and mechanical integrity. Moreover, the incorporation of perylene-based chromophores exhibits excellent structural compatibility with the PI backbone, acting as reinforced components rather than stress-concentrating defects. Consequently, the fibers exhibit simultaneous enhancements in mechanical properties and exceptional color fastness against harsh environments. This work establishes a cost-effective and scalable paradigm for the functionalization of PI fibers, contributing to the expanding application of PI fibers in high-end textiles and smart wearables. Download: Download high-res image (238KB) Download: Download full-size image