Electrospinning of cellulose acetate nanofiber membrane using methyl ethyl ketone and N, N-Dimethylacetamide as solvents

Cellulose acetate (CA) nanofiber membrane was prepared by electrospinning method using solvent mixtures of methyl ethyl ketone (MEK) and N, N, - dimethylacetamide (DMAc) in different ratios (2:1, 1:1, 1:2) and also different concentration of CA (7-19%). MEK was selected in place of acetone due to its high boiling point, thereby, minimises the evaporation loss of the solvent enabling the longer duration of electrospinning. The morphology of electrospun nanofibers was observed by Scanning Electron Microscope (SEM). It was observed that cylindrical fibers formed at higher concentration of polymer with increase of DMAc. Fiber diameters were in the range of 40-500 nm with large diameters formed at higher polymer concentration. Contact angle measurement revealed that membranes have good wetting property. The water flux measurements of membranes were carried out under gravity. A water flux of 10,197 Lm(-2) h(-1) was measured initially and was reduced subsequently to 365-200 Lm(-2) h(-1). The membranes could be reused up to four times without rupture. The above experiments suggest that MEK and DMAc could be an alternate solvent system in addition to other systems.