Flexible sensing fibers based on polyaniline-coated polyurethane for chloroform vapor detection

Abstract

Novel flexible composite fibers with good structural stability were fabricated by coating nanostructured polyaniline (PANI) layers on the surface of traditional polyurethane (PU) fibers through in situ chemical oxidative polymerization. Their chemoresistive characteristics for organic vapor compounds showed a rapid and sensitive response, and especially high selectivity. The influence of the fiber structures on the sensing properties for chloroform vapor detection was further discussed, and some features such as high sensitivity (4 × 10⁻⁴ ppm⁻¹), fast response time (less then 30 s), and low detection limit (30 ppm) were achieved. The remarkable sensing performances of the composite fibers are not only related to the change in the conformation of the PANI chains, but also in the conducting pathway of the PANI layers due to the reversible solvent-swelling of the PU matrix.