Fabrication of Luminescent Thermoplastic Polyurethane Fibers through Surface Functionalization with AIEgens

Luminescent fibers with aggregation-induced emission (AIE) characteristics possess great application potential in functional and smart textiles. However, introduction of AIE luminogens (AIEgens) through a blending method often affects the mechanical properties of fibers, and the optical properties of AIEgens, especially those containing donor–acceptor (D–A) push–pull electronic structure, are also influenced by the fiber matrix. In this work, luminescent thermoplastic polyurethane (TPU) fibers with high luminescence performance and excellent mechanical properties were prepared by a facile surface functionalization method with AIEgens. Benefiting from the synergistic effect of hydrogen bonding and chemical bonding, even when the dye concentration is as low as 0.1 mg mL–1 and the staining time is as short as 1 min during the dyeing process, the resulting fibers emit bright fluorescence (blue and red, respectively) under ultraviolet light excitation. Meanwhile, the luminescent fibers still maintain the excellent mechanical properties of TPU fibers, which allow weaving them into functional fabrics for flexible pattern displays, clothing designs, and anticounterfeiting. Compared with many reported luminescent fibers obtained through blending or chemical modification, our approach to combine AIEgens and fibers through surface functionalization shows great potential in luminescent fibers/fabrics.