Elastic electrospun membrane with stable temperature and humidity fluorescence performance for metal dust detection

Metal dust prevention and control is the safety guarantee for industrial production. In order to effectively improve the stability and portability of detection, fluorescent polyimide with excellent thermal stability (thermal decomposition temperature around 400 °C in air) and solubility was synthesized. Specifically, the pyrene units were introduced into the molecule chain as the side groups, endowed the polymer with good processability. The dimensional stability of the detector is an important factor affecting the sensitivity and reusability. Therefore, polymers with different morphologies were composited onto polyurethane membranes. The results showed that polyimide dispersed evenly on the substrate layer had the excellent fluorescence and mechanical performance. The repeated tensile strain and strength of optimized membrane could reach 350 % and 3.5 MPa, respectively. Furthermore, the influence of humidity on the fluorescence of membrane was relatively small, which was attributed to the waterproof performance of the sample. In response to metal dust, the sample appeared a significant fluorescence enhancement effect on Fe dust. Compared with the high-precision commercial instrument, our fiber detector is not only effective but also have the advantage of real-time monitoring. This work provides a way for the visualization of metal dust recognition sensor with flexible and wearable in the future.