Poly(vinyl alcohol)/chitosan oligosaccharide blend submicrometer fibers prepared from aqueous solutions by the electrospinning method

Submicrometer fibers of poly(vinyl alcohol) (PVA) and chitosan oligosaccharide [COS; i.e., (1→4)-2-amino-2-deoxy-β-D-glucose] were prepared by an electro-spinning method with aqueous solutions with polymer concentrations of 7.5-15 wt%. Scanning electron microscopy, Fourier transform infrared, X-ray diffraction, differential, scanning calorimetry, and thermogravimetric analysis were used to characterize the morphology and properties of the PVA/COS fibers. The PVA/COS mass ratio, the total polymer concentration, and processing parameters such as the applied voltage and capillary-to-collector distance played important roles in controlling the fiber morphology. Fourier transform infrared and X-ray diffraction data demonstrated that there were possibly hydrogen bonds between COS and PVA molecules that weakened the interactions in COS and improved the electrospinnability of PVA/COS. Moreover, with a higher percentage of COS in the PVA/COS blend fibers, superior thermal stability could be obtained.