Free volume and alcohol transport properties of PDMS membranes: Insights of nano-structure and interfacial affinity from molecular modeling

Molecular simulation study of penetrant gas transport properties into the pure and nanosized silica particles filled polysulfone membranes

“…The well-known experimental method to measure the cavity size distribution of a material is the Positron annihilation lifetime spectroscopy (PALS) [22,37,39,49]. But this is still a very difficult technique and the molecular modeling can provide an alternative method, namely cavity energetic-sizing algorithm (CESA) [63], to investigate the cavity size distribution of membranes.…”

“…Molecular diffusion through a polymer membrane depends strongly on its morphology and free volume. The free volume is the sum of the static voids which are created by chain packing or transient gaps generated by thermally induced chain rearrangement and provides the diffusing molecules a low-resistance path for its transport [37,39,49,78]. The larger and more numerous free volume elements, would allow larger numbers of gas molecules to migrate through a polymer based membrane.…”

“…In several studies, many researchers applied molecular simulation to the model systems to predict the transport properties (solubility, diffusivity and permeability) of various gases into the desirable nanocomposite polymeric membranes [26,[46][47][48][49]. For example, Odegard et al [50] simulated the silica nanoparticle/ polyimide composites with various nanoparticle/polyimide interfacial treatments to predict their elastic properties.…”

Composite hollow fiber membranes with different poly(dimethylsiloxane) intrusions into substrate for phenol removal via extractive membrane bioreactor

“…The Si-O units that comprise the PDMS backbone make it a highly flexible polymer and thus small molecules are able to transport through the free volume of PDMS. In addition, PDMS exhibits hydrophobicity and organophilicity, making it highly permeable for organic compounds [14,15]. However, phenol transfer rate across PDMS membranes has been found to be much lower compared with those of other aromatic compounds such as toluene, benzene, and monochlorobenzene [16,17].…”

Pervaporation performance of PPO membranes in dehydration of highly hazardous mmh and udmh liquid propellants

“…Molecular simulations were performed using the discover package of MS modeling software by employing the COMPASS (condensed-phase optimized molecular potentials for atomistic simulation studies) force field [18]. This force field has been widely used to optimize and predict the structural, conformational, and thermo-physical condensed phase properties of polymers.…”