Glass nanofibers and lanthanide aluminate nanoparticles as reinforcement nanofillers for polyurethane composite toward smart applications

Abstract

Mechanically reliable photoluminescent bricks were prepared from polyurethane (PUR) by reinforcement with electrospun glass nanofibers (EGNF). To enhance the mechanical qualities of the PUR sheets, EGNF were electrospun and applied to the PUR sheets as a reinforcement agent. We physically incorporated nanoparticles of rare-earth doped strontium aluminate (NRSA) into EGNF@PUR bricks to create photoluminescent and photochromic properties. In order to confirm the transparency of EGNF@PUR with the ability to change color to greenish beneath ultraviolet irradiation, both photoluminescence spectra and CIE (Commission Internationale de l'Eclairage) Lab coordinates were examined. When irradiated at 365 nm, an emission peak was monitored at 519 nm. With low concentrations of NRSA, the emission characteristic of the EGNF@PUR hybrid bricks was immediately reversible, revealing fluorescence emission. Persistent emission with delayed reversibility was observed in EGNF@PUR when using high concentrations of NRSA. Examining the morphological properties of NRSA and EGNF using transmission electron microscopy (TEM) revealed diameters of 4-9 nm and 75-125 nm, respectively. Both EGNF and EGNF@PUR bricks were subjected to morphological analysis using different analytical methodologies. As the concentration of NRSA rose, the material became more hydrophobic and more ultraviolet-protective. When compared to NRSA-free EGNF@PUR bricks, those containing NRSA had superior scratch resistance.