the microphase separation of hydrated perfluorinated sulfonic acid membrane nafion was investigated using dissipative particle dynamics (dpd). the nafion as a polymer was modelled by connecting coarse grained beads which corresponds to the hydrophobic backbone of polytetrafluoroethylene and perfluorinated side chains terminated by hydrophilic end particles of sulfonic acid groups [1, 2]. each f...

The microphase separation of hydrated perfluorinated sulfonic acid membrane Nafion was investigated using Dissipative Particle Dynamics (DPD). The nafion as a polymer was modelled by connecting coarse grained beads which corresponds to the hydrophobic backbone of polytetrafluoroethylene and perfluorinated side chains terminated by hydrophilic end particles of sulfonic acid groups [1, 2]. Each f...

From in vitro experiments it is known that human endothelial cells show poor adhesion to hydrophobic polymers. The hydrophobicity of vascular prostheses manufactured from Teflon or Dacron may be the reason why endothelialization of these grafts does not occur after implantation in humans. We modified films of polytetrafluoroethylene (Teflon) by nitrogen plasma and oxygen plasma treatments to ma...

In this paper, we describe the surface modification of polytetrafluoroethylene (PTFE) through plasma treatment process. Several parameters including different active gases, RF power, distance between source and sample, duration were optimized to reduce hydrophobic nature PTFE. Three gases used (i.e., N2, O2, (Ar+H2)); N2 was effective hydrophobicity PTFE within a shorter 2 min. characterization...

The fabrication of activated carbon air cathodes for larger-scale microbial fuel cells requires a diffusion layer (DL) that is highly resistant to water leakage, oxygen permeable, and made using inexpensive materials. A hydrophobic polyvinylidene fluoride (PVDF) membrane synthesized using a simple phase inversion process was examined as a low cost ($0.9/m(2)), carbon-free DL that prevented wate...

The electrochemical sensor for detecting hydrogen sulfide was fabricated. H2S gas molecules pass through polytetrafluoroethylene membrane with 0.22 mm pore size. Carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) were used to fabricate working and counter electrodes. It can be seen from Field Emission Scanning Electron Microscopy (FESEM) images of the working electrode that...

Recovery of ammonia (NH3) from residual waters offers various reuse opportunities, such as the production fertilisers and generation electricity heat. However, simultaneous evaporation water (H2O) during NH3 stripping under vacuum results in diluted recovered gas with high H2O contents. Whereas porous gas-permeable membranes are already used for stripping, use non-porous silica-based pervaporat...

As the hydrogen market is projected to grow in next decades, development of more efficient and better-performing polymer electrolyte membrane fuel cells (PEMFCs) certainly needed. Water management one main issues faced by these devices strictly related employment fluorinated materials gas diffusion medium (GDM). Fluorine-based polymers are added as hydrophobic agents for layers (GDL) or ink com...