IRANIAN POLYMER JOURNAL, vol.30, pp.873-883, 2021 (SCI-Expanded)
Polyurethane (PU)/poly(lactic acid) (PLA) blends having different weight ratios (80:20, 60:40, 50:50, 40:60 and 20:80) were prepared in a suitable solvent environment. A new non-woven fiber surface with a single structure was obtained from the prepared PU/PLA blend solutions by electrospinning method. The effect of different weight ratios on the characteristic properties of PU/PLA fibers was investigated. The obtained electrospun mats were characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffractometry (XRD), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), tensile and contact angle tests. The most homogeneous fiber distribution was observed at the structure of 6PU/4PLA (60PU:40PLA w/w) nanofiber. Besides, this fiber was determined to have the highest strength and tensile strain-at-break. Among all fibers, the highest contact angle was observed for 8PU/2PLA (80PU:20PLA w/w) fiber, indicating a hydrophobic structure. According to the DSC results, the melting values of the soft and hard segments of pure PU showed only a melting peak. In XRD results, all electrospun mats which were obtained by blending PLA and PU showed a semi-crystalline structure with low crystallinity. However, these specified fibers showed the thinnest diameter. Thanks to PU/PLA fibers, a new, thinner and more flexible biodegradable surface with perfectly good physical and mechanical properties was obtained. It is expected that the obtained PU/PLA fibers will find a wide range of applications in filtration, liquid-repellent surfaces, medical as wound dressing, and industrial fields.