Cellulose derivative and liquid crystal blend membranes for oxygen enrichment

Citation
Xg. Li et al., Cellulose derivative and liquid crystal blend membranes for oxygen enrichment, EUR POLYM J, 35(1), 1999, pp. 157-166
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
EUROPEAN POLYMER JOURNAL
ISSN journal
0014-3057 → ACNP
Volume
35
Issue
1
Year of publication
1999
Pages
157 - 166
Database
ISI
SICI code
0014-3057(199901)35:1<157:CDALCB>2.0.ZU;2-6
Abstract
Oxygen enriching property and stability of the blend membranes, 10-45 mu m thick, fabricated from ethyl cellulose, cellulose nitrate, cellulose diacet ate, and cellulose triacetate, with thermotropic cholesteric or nematic liq uid crystals (LC). such as cholesteryl oleyl carbonate, p-heptyl-p'-cyanobi phenyl, p-pentylphenol-p'-methoxybenzoate, benzoate containing liquid cryst al mixture, and triheptyl cellulose, were studied by a variable volume meth od. The membranes with 1.5-4 wt% LCs showed the maximum oxygen-enriching ab ility in the temperature range of their LC phase. The oxygen-enriched air f lux Q(OEA) and the oxygen concentration Y-O2 increased simultaneously as th e operating pressure increased. The 30 mu m-thick triheptyl cellulose-ethyl cellulose (8/92) homogeneous membrane exhibited almost constant oxygen- en riching efficiencies of Q(OEA) 1.0 x 10(-4) ml(STP)/s . cm(2) and Y-O2 40% at 30 degrees C and 0.41 MPa in a single step for a 35 day operating time. (C) 1998 Elsevier Science Ltd. All rights reserved.