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Journal articles
Covalent and Selective Grafting of Polyethylene Glycol Brushes at the Surface of ZIF-8 for the Processing of Membranes for Pervaporation
Abstract : The so-called Graftfast reaction in water and at room temperature (RT) was applied to graft polyethylene glycol (PEG) at the surface of the microporous zeolitic imidazolate framework ZIF-8 nanoparticles (NPs) using acrylPEG of different chain lengths (480 Da and 5 kDa). In comparison to non-modified ZIF-8 NPs, both chemical and colloidal stabilities of PEGylated ZIF-8 NPs are significantly enhanced in water. A series of colloidal complex fluids by mixing PEG grafted ZIF-8 (i. e. PEG-g-ZIF-8) NPs with different amounts of polyvinylalcohol (PVA) was prepared and characterized by advanced characterization tools such as dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS) thereby showing their long-term colloidal stability. Finally, dense and supported mixed matrix membranes were cast from PEG-g-ZIF-8/PVA solutions and have shown high performance in isopropanol (IPA) dehydration by pervaporation. The permeation flux of the supported MMM (i. e. 0.091 kg/(m$^2$h) is eleven times higher than that of the pure PVA membrane and these MMMs present a high separation factor (i. e. 7326). These transport properties are presumably due to the molecular sieving effects induced by ZIF-8 and the good interfacial properties of the membrane. The computational exploration of the ZIF-8/PVA and PEG/PVA interfaces provides a microscopic scale explanation for the enhanced compatibility of PVA with the PEGylated MOF when compared to that for the composite based on the bare ZIF-8 as a filler.
Cited literature [79 references]
https://hal-cea.archives-ouvertes.fr/cea-02072200
Contributor : Serge Palacin Connect in order to contact the contributor
Submitted on : Tuesday, March 19, 2019 - 8:47:17 AM
Last modification on : Friday, April 1, 2022 - 9:37:11 AM
Long-term archiving on: : Thursday, June 20, 2019 - 12:47:23 PM
Contributor : Serge Palacin Connect in order to contact the contributor
Submitted on : Tuesday, March 19, 2019 - 8:47:17 AM
Last modification on : Friday, April 1, 2022 - 9:37:11 AM
Long-term archiving on: : Thursday, June 20, 2019 - 12:47:23 PM
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Benzaqui_ACSSCE2019_V0.pdf
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