Electrospun polyimide nanofibrous membranes for absorption of oil spills

The demand for an efficient method for absorbing oil in harsh environments is increasingly urgent around the world. In this study, polyimide nanofibrous membranes were fabricated via electrospinning of polyamic acid precursor solutions followed by a thermal imidization. Polytetrafluoroethylene (PTFE) microparticles were added to modify the performance of polyimide nanofibrous membrane. Their morphologies were observed by field emission scanning electron microscopy, which revealed that polyimide nanofiber diameters ranged from 200 +/- 20 to 350 +/- 35 nm by adjusting polyamic acid concentrations. Polytetrafluoroethylene microparticles were embedded in polyimide matrices, which enhanced the mechanical strength and hydrophobicity of the polyimide nanofibrous membrane. Adding 1.8% polytetrafluoroethylene microparticles, the tensile strength of sample P6 was increased by 6.44-fold and water contact angles rose from 105 to 133 degrees. Sample P2 had a maximum oil adsorption capacity of 2650% and a water contact angle of 107 degrees, which might be considered a competitive future candidate for oil absorption at high temperatures.