Application of polyhedral oligomeric silsesquioxane to the stabilization and performance enhancement of poly(4‐methyl‐2‐pentyne) nanocomposite membranes for natural gas conditioning

Abstract

The application of octatrimethylsiloxy polyhedral oligomeric silsesquioxane (POSS) nanoparticles was investigated in the fabrication of novel reverse‐selective poly(4‐methyl‐2‐pentyne) (PMP) nanocomposite membranes for the separation of heavier hydrocarbons from methane. Generally, PMP and PMP–fumed silica (FS) nanocomposite membranes suffer severe physical aging with approximately 40% permeation flux reduction over 120 days. A straightforward strategy was introduced to suppress the physical aging of PMP and also to improve the thermal stability without compromising the selectivities and permeabilities through the incorporation of a functionalized POSS–FS binary filler system. Fourier transform infrared spectroscopy and scanning electron microscopy proved productive interactions between the fillers and polymer, with a fair compatibility between them. Thermogravimetric analysis confirmed that the thermal stability of the neat PMP was enhanced by the incorporation of the fillers into the nanocomposites. The addition of POSS and FS led to improved operational performance, such as in the permeability and selectivity, over the neat PMP. The permeation stabilities of the PMP–POSS and PMP–FS–POSS nanocomposite membranes were clearly improved over a long time (120 days). The permeation data indicated that the PMP–3 wt % POSS–20 wt % FS nanocomposite membrane is promising for C3H8/N2 and C3H8/CH4 separation. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45158.

Loading-Dependent Diffusion of SO2 in 13X and 5A Using Molecular Dynamics: Effects of Extraframework Ions and Topology

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The State-of-the-Art Functionalized Nanomaterials for Carbon Dioxide Separation Membrane

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“…Great efforts have been devoted to reduce the particle size of MOFs and zeolite to improve their compatibility with the polymer matrix [ 113 ] and to introduce building units with specific gas adsorption capacity [ 114 , 115 ]. When incorporated into a polymer matrix with high free volume such as glassy polyacetylenes, cage-like POSS act as rigid barrier rendering a space-filling effect to reduce the relaxation of a polymeric chain and collapse of free volume cavities [ 116 ]. The large free volume occupied by a 3D POSS can effectively suppress physical aging.…”