Influence of the solvent and nonsolvent composition on the electrospinning of a cellulose acetate ternary system

A series of cellulose acetate (CA) ternary system solutions consisting of the CA, N,N-dimethylacetamide, and various non-solvents, such as 1-propanol, 1-hexanol, 1-octanol, 1-decanol, 1,3-propane diol, and glycerol, were prepared, and the effects of the component composition on the solutions characteristics and electrospinning were examined. In particular, the effects of the nonsolvent concentration, structure, and degree of miscibility with other components were studied. In some cases, increasing the nonsolvent content increased the solution viscosity and facilitated the electrospinning process. However, we found that electrospinning was also governed by the structure of the nonsolvents and by the solution viscosity. An increase in the number of hydroxyl groups or an increase in the hydrocarbon chain length of the monohydroxyl alcohol nonsolvent improved the fiber formation. The calculated Hansen sphere [D(S-p)] values of the CA ternary system solution were then used to explain their electrospinnability. The increases in the hydrophilicity and hydrophobicity of system caused by changes in the nonsolvent structure increased the D(S-p) values and improved fiber formation in electrospinning process. The calculated D(S-p) values were also shown to be in good agreement with the obtained microscopy images of the electrospun fiber. (C) 2015 Wiley Periodicals, Inc.