Organosilane modified silica/polydimethylsiloxane mixed matrix membranes for enhanced propylene/nitrogen separation

► Two types of chlorosilanes were successfully incorporated on fumed SiO2 surface via silanization. ► FTIR spectroscopy and elemental analysis confirmed the surface modification of SiO2. ► Defect-free composite PDMS films were produced with surface-modified SiO2 as fillers. ► PDMS membranes with surface-modified SiO2 exhibited enhanced C3H6/N2 permselectivities.