Electrospun polystyrene (PS) fibre mat has been shown to have great potential as an oil sorbent due to its high sorption capacity and oil-water selectivity. Poor mechanical properties, due to the lack of inter-fibre bonding, has been a limiting factor in its use in such applications. In this study, mats of polymer-blends of polystyrene (PS) and thermoplastic polyurethane (PU) fibres, in different polymer weight ratios, were produced and investigated for possible oil sorption application. A comprehensive physico-chemical, thermal, mechanical and sorption characterisation of the different polymer-blends was undertaken, to examine the effect of blend ratio on the fibre mat. Characterisation was by field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) spectroscopy, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, differential scanning calorimetry (DSC), thermo-gravimetric and differential analysis (TG-DTA), mechanical tensile testing, and by sorption analysis. The microstructural properties of the fibres appeared significantly dependent upon the relative blend ratio. DSC revealed that good interaction/miscibility existed between the two polymers. Tensile strength characterisation showed that a pure PS fibre mat had a poor tensile strength, but the value increased over one order of magnitude with the addition of PU in the polymer matrix, attributed to the formation of inter-fibre bonds. Conversely, the sorption capacity (SC) decreased with increasing PU addition. Modulating the blend ratio could therefore provide a balance between the desired sorption capacity and the mechanical behaviour of resultant mats. Sorption capacity is a complex interaction between fibre and mat characteristics but the polymer blend technique reported here offers a simple, effective and inexpensive method of addressing the poor mechanical properties of electrospun PS fibre by adding PU and via enhancing micro/nano scale interactions between the two polymers in the blend.
