Jh. Kim et al., Incorporation effect of fluorinated side groups into polyimide membranes on their pervaporation properties, J MEMBR SCI, 169(2), 2000, pp. 185-196
Incorporation effects of fluorinated alkyl side groups into polyimide membr
anes on their pervaporation properties were investigated for several dilute
aqueous organic solutions. The pervaporation experiments were carried out
as functions of the nature of permeating solvents, feed concentration, perm
eate pressure and feed temperature. The polyimide membranes containing fluo
rinated side groups showed high pervaporation selectivity and high permeati
ng flux towards hydrophobic solvents. They were explained in terms of their
enhanced sorption/sorption selectivity and concentration-average diffusion
coefficient/diffusivity selectivity towards organic solvent over water due
to enhanced hydrophobicity and increased fractional free volume (FFV) obta
ined by the introduction of fluorinated side groups. (C) 2000 Elsevier Scie
nce B.V. All rights reserved.