Blend electrospinning of citronella or thyme oil-loaded polyurethane nanofibers and evaluating their release behaviors

Abstract

Integration of essential oils into nanofibers not only enhances the bioactivity of these substances but also offers greener solutions for many applications including protective textiles and coatings. Herein, citronella or thyme oil-loaded polyurethane nanofibers were fabricated via blend electrospinning, and their release behavior was evaluated. Initially, polyurethane nanofibers with different citronella or thyme oil concentrations (5%, 10%, and 15%) and spinning parameters (tip-to-collector distance: 15-20 cm, voltage: 15-20 kV) were fabricated. The nanofiber mats were characterized in terms of surface morphology, wettability, and porosity. Afterward, the release behaviors of the selected mats were examined. Depending on the oil concentration and spinning parameters, nanofibers with diameters in the range of 175-442 nm were produced. The incorporation of essential oil increased contact angles from 102 degrees to 125 degrees, while the bulk porosities were decreased from similar to 76% to similar to 58%, depending on the oil. Fourier-transform infrared spectroscopy analysis validated successful essential oil integration. The release studies revealed that thyme oil exhibited a release of similar to 10% and citronella essential oil similar to 5% over 18 h, indicating a controlled and sustained release. This study demonstrates the potential of essential oil-loaded polyurethane nanofibers as eco-friendly materials for protective textiles and coatings.