$\mathrm{C}_{60}$ fullerene-containing polymer stars in mixed matrix membranes

Star-shaped macromolecules with $\mathrm{C}_{60}$ fullerene branching centers were used as modifiers of poly($2.6$-dimethyl-$1.4$-phenylene oxide) matrix to obtain mixed matrix membranes. Two types of star modifiers were synthesized i) six-arms star with six polystyrene arms grafted onto $\mathrm{C}_{60}$ center and ii) twelve-arms hybrid star with six polystyrene arms and six copolymer poly($2$-vinylpyridine)-block-poly(tert-butylmethacrylate) arms grafted onto $\mathrm{C}_{60}$ center. The membrane structures were studied by scanning electron microscopy. The transport properties of the membranes were determined by using sorption and pervaporation tests toward methanol and ethylene glycol over a wide concentration range. All membranes showed high affinity for methanol. The separation factor reached its maximum level at 5 wt% modifier concentration in the membrane. Polar hybrid arms were shown to change the membranes’ morphologies and considerably improve their transport properties.