Preparation and mechanical properties of silicon oxycarbide fibers from electrospinning/sol–gel process

Silicon oxycarbide (SiOC) fibers were produced through the electrospinning of the solution containing vinyltrimethoxysilane and tetraethoxysilane in the course of sol–gel reaction with pyrolysis to ceramic. The effect of the amount of spinning agent Polyvinylpyrrolidone (PVP) on the dope spinnability was investigated. At a mass ratio of PVP/alkoxides = 0.05, the spinning sol exhibited an optimal spinnable time of 50 min and generated a large quantity of fibers. Electrospun fibers were characterized by Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis–differential scanning calorimetry (TGA–DSC), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The SEM results revealed that the SiOC fibers had a smooth surface and dense cross-section, free of residue pores and cracks. The XPS results gave high content of SiC (13.99%) in SiOC fibers. The SiOC fibers prepared at 1000 °C had a high tensile strength of 967 MPa and Youngʹs modulus of 58 GPa.