Thermosensitive luminous fibers based on cresol red-boric acid reversible thermochromic pigments

In this study, thermosensitive luminous fibers (TLFs) were prepared by wet spinning, using polyacrylonitrile as the filament material and rare-earth long-afterglow luminescent materials as the optical source. Reversible thermochromic cresol red-boric acid (CB) pigment in the TFLs served as the luminescence conversion agent. The reflectivity curves and fluorescence spectra were recorded at 25 and 65 °C to investigate the thermosensitive characteristics of the TLFs. The results demonstrated that CB pigment functioned as a luminescent conversion agent that could convert the luminescence of rare-earth luminescent materials depending on the temperature. The luminescence of the TLFs can be converted from blue to fuchsia upon changing their temperature due to the structural transformation of the CB dye. The thermosensitivity can also be verified by observing the TLFs in water at 65 °C with the naked eye.