Fabrication and properties of poly(tetrafluoroethylene) nanofibres via sea-island spinning

Abstract Polytetrafluoroethylene (PTFE) has some unique properties such as high hydrophobicity and high resistance to elevated temperatures, chemicals and solvents which make it of interest for fibres and textiles. However, PTFE normally decomposes before melting, meaning that it cannot be readily melt-spun into fibres. In addition, PTFE is insoluble in all common organic solvents, prohibiting its use in common solution spinning methods such as dry, wet or electrospinning. Here we aim to develop an easy and environmentally friendly alternative for the production of PTFE nanofibres, using a modified island-in-the-sea solution spinning process. For this, first a dispersion of a PTFE homopolymer, PVA and water are compounded to create a blend of PTFE particles in a PVA solution. After the solid-state drawing of this blend and removal of the PVA, we are able to collect PTFE nanofibres with finest diameters of around 50 nm and lengths up to 15 μm. The effects of blend composition, morphology and drawing on PTFE fibre formation and properties are studied and discussed.