In this paper, a novel bi-layered Janus fibrous electrospun membrane with robust moisture permeable, breathable and directional water transport properties is successfully fabricated and reported for the first time.

This study aims to produce polypropylene (PP)/titanium dioxide (TiO2) melt-blown membranes for oil/water separation and photocatalysis. PP and different contents of TiO2 are melt-blended to prepare master batches using a single screw extruder. The master batches are then fabricated into PP/TiO2 melt-blown membranes. The thermal properties of the master batches are analyzed using differential scanning calorimetry and thermogravimetric analysis, and their particle dispersion and melt-blown membrane morphology are evaluated by scanning electron microscopy. TiO2 loaded on melt-blown membranes is confirmed by X-ray diffraction (XRD). The oil/water separation ability of the melt-blown membranes is evaluated to examine the influence of TiO2 content. Results show that the thermal stability and photocatalytic effect of the membranes increase with TiO2 content. TiO2 shows a good dispersion in the PP membranes. After 3 wt.% TiO2 addition, crystallinity increases by 6.4%, thermal decomposition temperature increases by 25 °C compared with pure PP membranes. The resultant PP/TiO2 melt-blown membrane has a good morphology, and better hydrophobicity even in acetone solution or 6 h ultraviolet irradiation, and a high oil flux of about 15,000 L·m−2·h−1. Moreover, the membranes have stabilized oil/water separation efficiency after being repeatedly used. The proposed melt-blown membranes are suitable for mass production for separating oil from water in massively industrial dyeing wastewater.

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A bark-like imitated polypr opylene (PP)/polycarbonate (PC) nanofibrous membrane was constructed by one-step meltblown technique for efficient particulate matter (PM) removal. The effects of PC content (0%, 1%, 3%, 5%, and 7%) on membrane thermal stability, microscopic characteristics, filtration performance, hydrophilicity, and water vapor transmission were investigated. The results demonstrated that using facile design of incompatibility and viscosity difference between PC and PP polymers decreases average fiber diameter, creating a bark-like groove appearance and increasing surface potential, making a new PP/PC membrane with high filtration performance. The resultant PP/PC membrane had finer average fiber diameter of 0.63 μm, which was nearly 89.41% lower than PP membranes (5.95 μm), and its quality factor (0.036 Pa−1) was nearly 2.12 times than that of PP membranes (0.017 Pa−1) with the die hole diameter of 0.5 mm. This fabrication technique of a special meltblown filter membrane saves the cost of die retrofitting and post-processing, which provides an innovative method for particulate efficient removal of high efficient filters.