Polycarbonate/silica nanocomposite membranes: Fabrication, characterization, and performance evaluation

Abstract

Polycarbonate/silica nanocomposite membranes at low silica loading were fabricated by solution blending and solvent evaporation technique. The functionalized silica nanoparticles used were synthesized by co-condensing hydrolyzed tetraethylorthosilicate with 3-aminopropyl trimethoxysilane in the sol-gel process. The membranes morphology, composition, surface, structure, thermal and mechanical properties were analyzed by the standard characterization techniques. The gas permeation tests were conducted in four-channel permeation cells. Field emission scanning electron microscopy results reveal that membranes above 3 wt % silica content formed distinguishable voids and agglomerates. Fair distribution of silica nanoparticles and absence of residual solvents were observed by energy dispersive X-ray and thermogravimetric analysis. Fourier transform infrared spectroscopy spectra confirmed the presence of new functional groups (NAH) and (OAH) bonds. The X-ray diffraction pattern revealed the polymer-particle interactions, the formation of rigidified polymer chain, and nanostructured silicon crystals. Further, the thermogravimetric analysis results revealed thermal stability enhancement while differential scanning calorimetry results of increased glass transition temperatures confirmed the presence of rigidified polymer chain. Furthermore, enhancements in mechanical strength of the membranes were observed. Moreover, at all feed pressures, increased CO 2 , N 2 , and CH 4 gas permeation was observed. At 6 bar feed pressure, the CO 2 /N 2 and CO 2 /CH 4 ideal selectivities of PC membranes with 3 wt % silica loading have increased from 19.2 to 38.0 and 29.2, respectively.

Probing toughness of polycarbonate (PC: ductile and brittle)/polypropylene (PP) blends and talc‐triggered PC/PP brittle composites with diverse impact fracture parameters

“…Polycarbonates (PCs) are one of the most common engineering plastics used in a myriad of applications ranging from household appliances to medical devices because of their transparency; ductility; and good mechanical, physical, thermal, flame‐retardant, and electrical properties . There have been attempts to extend the PC to commodity plastic applications by incorporating inexpensive inorganic fillers such as talc and calcium carbonate, and blending with partially miscible commodity plastics such as polystyrene (PS), polyethylene (PE), and polypropylene (PP) .…”

CO2-Philic [EMIM][Tf2N] Modified Silica in Mixed Matrix Membrane for High Performance CO2/CH4 Separation

“…The dense flat sheet membrane was prepared from a solution consisting of PC (20 wt%), DCM (80 wt%), and modified silica particles (3 wt% of total polymer-solvent solution, optimum loading as recommended elsewhere [34]). The PC polymer was first dried in an oven at 60 ∘ C for 24 h to remove adsorbed moistures.…”

“…Gas permeation test was done by using a constant pressure variable volume method in a four channel permeation cells setup [34]. The membranes were tested against pure gases in a sequence from CH 4 to CO 2 .…”

Compatibilizing effects for semicrystalline polymer‐infiltrated amorphous polymer matrix: Mechanical (toughness), thermal, and morphological behavior of compatibilized polypropylene/polycarbonate blends

“…at room temperature. The specimen dimensions were 64 × 12.7 × 3.2 (or 6.4) mm 3 . The notch depth of specimens was 2.5 mm.…”

“…Polycarbonates (PCs) have been extensively used in numerous applications such as electronic and medical devices, due to their transparency, ductility, mechanical robustness, electrical properties, and reasonable price. [1][2][3][4] To further reduce the price, PCs have been routinely mixed with inexpensive inorganic fillers, such as talc and CaCO 3 , [5][6][7] or blended with polyolefins (also to further reduce the density) such as polyethylene and polypropylene (PP). [8][9][10][11] In addition to the monetary benefits, blend systems preferably reduce the viscosity, thereby enhancing processability of ductile PCs (M w > ca.…”