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Showing 1 to 17 of 17 for “"polybenzimidazole"”.
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Evaluation of polybenzimidazole as a selective metal sorbent and controlled release agent
Polybenzimidazole (PBI) is a high performance, high thermal stability, new generation polymer that has excellent resistance to acids, bases, organic solvents, and fuels. The imidazole functionality suggests, however, that PBI should exhibit strong affinity for certain metal ions, and could be …
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Novel Polyphenylquinoxaline and Polybenzimidazole Proton Exchange Membranes For High Temperature Fuel Cell Systems
… and better utilization of system-generated heat. Polybenzimidazoles (PBIs) have been identified as one of the most prominent candidates for high temperature PEMFCs due to their excellent thermal and oxidative stability, as well as their proton conducting ability.</p><p>Recently, a novel process …
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Synthesis and Characterization of Novel Polybenzimidazoles and Post-modifications for Membrane Separation Applications
Polybenzimidazoles, a class of aromatic heterocyclic polymers, are well known due to their remarkable thermal stability, mechanical properties and chemical resistance which are often required in extreme operation conditions. Because of these properties, polybenzimidazoles are excellent candidates …
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Polymeric and Polymer/Inorganic Composite Membranes for Proton Exchange Membrane Fuel Cells
… ether sulfone) with varied amounts of polybenzimidazole. The polybenzimidazole served to decrease the water uptake and methanol permeability of the membranes, resulting in promising DMFC and hydrogen/air fuel cell performance.
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Synthesis and Characterization of High Performance Polymers for Gas Separation Membranes
… especially polyimides, polybenzoxazoles and polybenzimidazoles for gas separation applications. An abundance of monomers and novel polymers were synthesized and fabricated into membranes. Thermally rearranged polybenzoxazoles and their precursor polyimides were systematically studied with …
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Kinetic and mechanistic investigations of polyimide formation and characterization of their blends with polybenzimidazoles
… polymer blends based upon polyimides and polybenzimidazole. Imidization kinetics were successfully followed by the quantitative non-aqueous titration of the amic acid functional groups as a function of reaction conditions. The homogeneous solution imidization processes were described by …
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Synthesis and Chacterization of Novel Polybenzimidazoles and High-Solids Meta-Polybenzimidazoles
… Recently, a new process was developed to produce polybenzimidazole gel membranes for use in high temperature PEM fuel cell systems, which uses polyphosphoric acid (PPA) as both the polycondensation agent and the casting solvent. This one-pot process, called the 'PPA Process', allows for the …
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MEMBRANE DEVELOPMENT FOR ORGANIC SOLVENT NANOFILTRATION APPLICATION
… and modification of polyimide (PI) and polybenzimidazole (PBI) membranes to obtain membranes with enhanced chemical, mechanical and thermal stability, improved permeance and selectivity, and great long-term performance for various applications. High-flux mixed matrix membranes (MMMs) for …
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The application of siloxane modified polyimides as high performance textile coatings
… solution concentration, solvent, and viscosity. Polybenzimidazole and Kevlar aramid multifilament yarns were immersion coated, dried, and evaluated. Due to the surface segregation of siloxane, these coated fibers advantageously displayed lower moisture sorption as measured in three environments …
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Fabrication of Zeolite MFI Membranes on Low Cost Polymer Supports
… supports and MFI membranes supported on mesh-polybenzimidazole supports. However, cracks formed after the treatments due to the damage of polymer layer by UV light and the mismatch of linear thermal expansion co-efficient, respectively. Another approach, which utilizes the open-pore MFI …
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Synthesis and Characterization of High Performance Polymers for Gas Separation and Water Purification Membranes and as Interfacial Agents for Thermplastic Carbon Fiber Composites
… of high performance polymers, specifically polybenzimidazoles (PBIs) for gas separation applications and polyimides (PI) for water purification and as interfacial agents for thermoplastic carbon fiber composites. Two methods for improving the gas transport properties (for H2/CO2 separation) …
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High Temperature Polymers for Proton Exchange Membrane Fuel Cells
… poly(arylene ether sulfone) copolymers and polybenzimidazole (PBI). Complexation of the sulfonic acid groups with the PBI structure reduced water swelling and proton conductivity. The enhanced proton conductivity of Nafion® membranes has been proposed to be due to the aggregation of the …
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Towards a Membrane Electrode Assembly for a Thermally Regenerative Fuel Cell
… in the alcohol-ketone pair was mPBI (m-phenylene polybenzimidazole). The mPBI had to be doped with H3PO4 to enable H+ conductivity. Unfortunately, some H3PO4 leached out of the H3PO4-doped mPBI when in the presence of the alcohol-ketone pair. MEAs that were created using H3PO4-doped mPBI were …
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High Performance Electrode Materials From Carbon Nanofibers with Tunable Pore Architectures
… the behavior of PAN and 6FDA-DABA. Therefore a polybenzimidazole (PBI) and 6FDD (6FDA-DAM:DABA) blend was chosen and the kinetic behavior was studied before and after compatibilizing with 2-methylimidazole (2-MI). Chapter 1 interprets the introduction which summarizes the history of …
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Characterization, Processing, and Synthesis of Extreme-Performance Continuous Carbon Nanotube Network Composites
… we produce extreme-performance polyimide and polybenzimidazole composites through green in-situ polymerizations (ISSP) in CNTs and macroscopic fiber networks. This approach utilizes superheated water and alcohol as a powerful medium to disperse monomers and initiate polymerization of …
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Technoeconomic and mechanistic insights into the electroreduction of carbon dioxide to value added chemicals
… 5, sub 5-nm gold nanoparticles supported on polybenzimidazole wrapped carbon nanotubes are reported as catalysts for the electroreduction of CO2 in a GDL electrode based alkaline flow electrolyzer. An onset cell potential of just –1.50 V and an onset cathode potential of just –0.02 V vs. RHE …
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Synthesis and Characterization of Multiblock Copolymer Proton Exchange Membranes for High Temperature Fuel Cell Applications
The potential success of a proton exchange membrane (PEM) fuel cell as an alternative energy source depends highly upon the development of high performance PEMs. Typically, state-of-the-art PEMs have been perfluorinated sulfonated ionomer membranes such as Nafion® by DuPont. Although these …