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The membrane of pure poly(4-methyl-1-pentene) (TPX) and the
4-vinylpyridine (4-VP) modified TPX membranes, TPX/P4-VP, were
prepared in this study. The induction of high hydrophilic 4-VP
monomer into the TPX matrix was synthesized by free radical
polymerization. The TPX/P4-VP membranes were used in the
pervaporation process for the separation of aqueous alcohol
solution and aqueous acetic acid solution. The effects of
additive P4-VP content on the membranes morphology,
crystallinity and thermal stability for these membranes were
studied by SEM, ${\chi}$-ray and TGA, respectively. The effect
of the P4-VP content on the pervaporation performance was
discussed in this study. The separation factor and the
permeation rate of TPX/P4-VP membrane with 3.6 wt\% P4-VP
content for separation of 25 $^{o}$C, 90 wt\% aqueous ethanol
solution are increased from 13 to 999 and decreased from 116 g/
m$^{2}$h to 45 g/m$^{2}$h, respectively. The permeation
mechanism of aqueous acetic acid solution through the TPX/P4-VP
membranes were studied by the FTIR and water permeation
behavior. The permeation mechanism was found to fit the
Michaelis-Menten equation. Due to this permeation mechanism,
the TPX/P4-VP membranes can effectively increase the separation
and permeation rate of the aqueous acetic acid solution to 807
and 68 g/m$^{2}$h, respectively.
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