The efficacy of electrospun polyurethane fibers with TiO2 in a real time weathering condition.

This study focuses on the behavior of electrospun polyurethane fibers filled with nano, micro spheres and nanotube TiO₂, thus nTiO₂, mTiO₂ or TiNT, under real time ultraviolet (UV) radiation. Analyses were conducted using scanning electron microscopy (SEM), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetric analysis and differential scanning calorimetry (DSC) techniques. Significant changes of thermoplastic polyurethane (TPU) + 0.5% nTiO₂ and TPU + 0.5% mTiO₂ fibers morphology, that is, agglomerated TiO₂ particles, were observed on material surfaces due to TPU fiber degradation, also supported by FTIR spectra given as reduction in the peaks intensities after UV radiation, especially in the case of TPU + 0.5% nTiO₂. Further, after UV radiation, the initial degradation temperature reduction of the hard segment for all materials was up to 40℃. A significant reduction in the final degradation temperature (from 397.8℃ to 274.1℃) was noticed for the mTiO₂ filled fibers, suggesting their photocatalytic activity, while T_g was increased up to 20℃ for almost all fillers added to TPU, thus indicating lower molecular chain mobility upon UV radiation. [ABSTRACT FROM AUTHOR]