Recycled poly(propylene-co-methy1 methacrylate) as printing binder for photoluminescent textiles

Abstract

Photochromic fabrics change color upon exposure to an external light source. Photoluminescent textiles can undergo phosphorescence or fluorescence emissions. Fluorescent textiles emit light only under an illumination light source, whereas phosphorescent textiles continue emitting light after switching the illumination light source off. Herein, an industrial spinning process was carried out to produce nonwoven fibrous mat from polypropylene plastic waste. Poly(propylene-co-methy1 methacrylate) binder was synthesized via free-radical polymerization of borane-containing polypropylene and methyl methacrylate. A screen-printing composite of rare-earth strontium aluminate nanoparticles and poly(propylene-co-methy1 methacrylate) binder was printed onto recycled nonwoven polypropylene fabrics to introduce photochromic and photoluminescent textiles. Direct application of aqueous pigment-binder composites comprising various ratios of inorganic pigment with outstanding thermal and photostability was deposited onto polypropylene textiles. Screen printing allowed for the application of a consistent photoluminescent layer onto polypropylene surface. The printed nonwoven polypropylene samples had their excitation tracked at 368 nm, and an emission wavelength at 519 nm. The printed cloth with lower phosphor concentrations were found to reversibly emit a green color only under ultraviolet light, demonstrating fluorescence emission. At greater phosphor concentrations, a reversible green emission was monitored under the excitation light source, and greenish-yellow afterglow in the dark. A number of analytical techniques were used to gather microscopic information on the morphology of pigment nanoparticles and printed polypropylene textiles. The phosphor nanoparticles were measured to have diameters of 8–23 nm as reported by transmission electron microscopy (TEM), while X-ray diffraction examination revealed a crystal size of 21 nm. Increasing the pigment ratio enhanced the fabric UV protection, antibacterial activity, and superhydrophobicity. Upon increasing the pigment ratio, the contact and sliding angles were observed to increase in the ranges of 127.5°–160.4° and 11-7°, respectively. The impacts of phosphor ratio on comfort and colorfastness were examined.