Improving mechanical properties of electrospun cellulose acetate nanofiber membranes by cellulose nanocrystals with and without polyvinylpyrrolidone

Good mechanical properties of electrospun nanofiber membranes are essential for their successful application for commercial applications by providing sufficient mechanical strength to withstand severe operational conditions and guarantee structural integrity. Cellulose acetate nanofiber membranes modified with both polyvinylpyrrolidone (PVP) coated cellulose nanocrystals (CNC@PVP) and pristine CNCs were prepared using the reinforcement concentration varying from 0 to 0.135 wt%. The stability of dispersed CNCs and CNC@PVP in dimethylacetamide (DMAc) were compared visually. The apparent viscosity as a function of shear rate was compared for both CNCs and CNC@PVP in electrospun solution. Internal structure of obtained nanofiber membranes were compared using scanning electron microscopy to reveal the nanofibers diameter and its distribution. FTIR was used to disclose the different chemical structure of the two groups of membranes. Mechanical properties of nanofiber membranes were also compared. Finally, the thermogravimetric analysis was utilized to compare the thermal stability of different nanofiber membranes.