Fabrication and Characterization of PVA/SPI/SiO2 Hybrid Fibres via Electrospinning Technique
In this work, an electrospinning technique was developed for the fabrication of poly(vinyl alcohol) (PVA)/soy protein isolate (SPI)/SiO2 hybrid fibres with PVA, SPI and tetraethyl orthosilicate (TEOS) as precursors. The effects of SiO2 content, sodium dodecylsulfate and electrospinning electrical field strength on the morphology and structure of the hybrid fibres were investigated. Scanning electron microscopy (SEM) showed that uniform hybrid fibres about 200 nm in diameter were obtained at a weight ratio of PVA to SPI 8:2, SiO2 content 5.0 wt.%, sodium dodecylsulfate 0.6 wt.% and electrical field strength 0.90 kV cm-1. X-ray diffraction (XRD) patterns showed that the crystalline structure of PVA was somewhat destroyed as PVA was hybridized with SPI and SiO2, and further destroyed under electrospinning process as the stretched molecular chains of the fibre solidified rapidly at high elongation rates, resulting in the amorphism of PVA/SPI/SiO2 hybrid fibres. Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) showed that the components of PVA, SPI and SiO2 nanoparticles were linked by hydrogen bonds or Si–O–C bonds in the hybrid fabric networks. Differential scanning calorimetry (DSC) tests showed that the presence of SiO2 nanoparticles considerably improved the thermal stability of the hybrid fibres. Therefore, the PVA/SPI/SiO2 hybrid fibres may have potential as a new fibre in dressings, tissue engineering or drug delivery.