ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
A dry process of chemical vapor deposition and polymerization (CVDP) was employed to prepare a polyimide composite membrane for water-ethanol separation, using an apparatus newly developed for this investigation. The characteristics of the apparatus were studied by depositing pyromellitic dianhydride (PMDA) and 4,4′-diaminodiphenyl ether (P,P′-oxydianiline, ODA) in a vacuum of 10-6 Torr. Deposited layers were converted to a thin polyimide film by heating at 200°C for 3 h in a vacuum. The composite membranes were prepared by forming a polyimide layer of 0.2 μm thickness on the surface of asymmetric supporting membranes made by the phase-inversion process. The polyimide composite membranes prepared under the best conditions exhibited a separation factor α (H2O/EtOH) of over 140 for 95 vol% aqueous ethanol solution with flux of 0.1 kg/m2 h at 25°C in pervaporation mode. Also, it was demonstrated that this new technique of chemical vapor deposition and polymerization (CVDP) was very useful for the preparation of a solvent-resistant composite membrane in a completely dry process. © 1993 John Wiley & Sons, Inc.
Additional Material:
11 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1993.070490402
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