Mixed matrix membranes of polysulfone/polyimide reinforced with modified zeolite based filler: Preparation, properties and application

In this work, polysulfone/polyimide (PSf/PI) mixed matrix membranes were fabricated by reinforcement of modified zeolite (MZ) particles through solution casting method for investigation of antibacterial activity against two gram negative bacteria (Salmonella typhi, Klebsella pneumonia) and two gram positive bacteria (Staphylococcus aureus, Bacillus subtilis). The modified zeolite particles were incorporated to PSf and PI matrix and the influence of these particles on thermal, mechanical and structural properties was evaluated. The morphological evolution was investigated through scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis, which revealed good compatibility between organic polymer matrix and inorganic filler. Mechanical stability was investigated by tensile testing while thermal analysis was evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). This revealed improvement in thermal properties with increasing filler concentration from 1 wt% to 10 wt%. Structural analysis was successfully done using X-ray diffraction analysis (XRD) and Fourier transform infrared (FTIR) spectroscopy. Solvent content of fabricated mixed matrix membranes was observed to decrease while moving from more hydrophilic to less hydrophilic solvent. However, addition of filler content enhanced the porosity of fabricated membranes. The synthesized mixed matrix membranes exhibited good antibacterial activity and the highest activity was shown by PSf/PI/MZ mixed matrix membrane. Therefore, the combination effect of PSf, PI and MZ sufficiently enhanced the antibacterial activity of mixed matrix membranes.