TY - JOUR
T1 - MOF-mixed matrix membranes: Precise dispersion of MOF particles with better compatibility via a particle fusion approach for enhanced gas separation properties
AU - Shahid, S.
AU - Nijmeijer, Dorothea C.
AU - Nehache, Sabrina
AU - Vankelecom, Ivo
AU - Deratani, Andre
AU - Quemener, Damien
PY - 2015
Y1 - 2015
N2 - Mixed matrix membranes (MMMs) incorporating conventional fillers frequently suffer from insufficient adhesion between the polymer matrix and the fillers. This often results in the formation of non-selective voids at the filler/polymer interface, which decreases the performance of the membrane. A novel approach is presented here to develop metal organic framework (MOF) based MMMs by using the self-assembly of MOF and polymer particles followed by their controlled fusion. MOF-polymer interaction is optimized through this strategy and it overcomes MOF-polymer incompatibility, MOF agglomeration and MOF distribution problems, happening especially at high loadings of MOFs when applying conventional methods. Matrimid® polymer particles were first prepared by precipitating a Matrimid® polymer solution in water. The surface of these particles was then modified by the introduction of imidazole groups, enhancing the chemical compatibility with the selected ZIF-8 MOF. ZIF-8 nanoparticles were then grown in-situ to this modified polymer particle suspension by addition of the precursor for ZIF-8 synthesis. The resulted suspension was cast to dryness and annealed in a solvent–vapor environment to induce particle fusion, leading to a dense MMM structure. Scanning electron microscopy (SEM) images showed an excellent dispersion of the ZIF-8 nanoparticles forming a percolating pathway without any agglomeration, even at 40 wt% loading of the ZIF-8. Excellent dispersion of ZIF-8 and an excellent ZIF-8-polymer interfacial adhesion resulted in a significant improvement in both CO2 permeability and CO2/CH4 selectivity. The CO2 permeability of the MMMs increased by 200% and the CO2/CH4 selectivity increased by 65% as compared to unfilled Matrimid®. More detailed analysis of the gas transport performance of the MMMs showed that the CO2 permeability and the CO2/CH4 selectivity are mainly governed by the increase in CO2 diffusivity. The presented approach is a very versatile MMM preparation route, not only for this specific ZIF and polymer but for a wide range of material combinations
AB - Mixed matrix membranes (MMMs) incorporating conventional fillers frequently suffer from insufficient adhesion between the polymer matrix and the fillers. This often results in the formation of non-selective voids at the filler/polymer interface, which decreases the performance of the membrane. A novel approach is presented here to develop metal organic framework (MOF) based MMMs by using the self-assembly of MOF and polymer particles followed by their controlled fusion. MOF-polymer interaction is optimized through this strategy and it overcomes MOF-polymer incompatibility, MOF agglomeration and MOF distribution problems, happening especially at high loadings of MOFs when applying conventional methods. Matrimid® polymer particles were first prepared by precipitating a Matrimid® polymer solution in water. The surface of these particles was then modified by the introduction of imidazole groups, enhancing the chemical compatibility with the selected ZIF-8 MOF. ZIF-8 nanoparticles were then grown in-situ to this modified polymer particle suspension by addition of the precursor for ZIF-8 synthesis. The resulted suspension was cast to dryness and annealed in a solvent–vapor environment to induce particle fusion, leading to a dense MMM structure. Scanning electron microscopy (SEM) images showed an excellent dispersion of the ZIF-8 nanoparticles forming a percolating pathway without any agglomeration, even at 40 wt% loading of the ZIF-8. Excellent dispersion of ZIF-8 and an excellent ZIF-8-polymer interfacial adhesion resulted in a significant improvement in both CO2 permeability and CO2/CH4 selectivity. The CO2 permeability of the MMMs increased by 200% and the CO2/CH4 selectivity increased by 65% as compared to unfilled Matrimid®. More detailed analysis of the gas transport performance of the MMMs showed that the CO2 permeability and the CO2/CH4 selectivity are mainly governed by the increase in CO2 diffusivity. The presented approach is a very versatile MMM preparation route, not only for this specific ZIF and polymer but for a wide range of material combinations
KW - IR-97354
KW - METIS-311936
U2 - 10.1016/j.memsci.2015.05.015
DO - 10.1016/j.memsci.2015.05.015
M3 - Article
VL - 492
SP - 21
EP - 31
JO - Journal of membrane science
JF - Journal of membrane science
SN - 0376-7388
ER -