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Showing 1 to 20 of 20 for “"disulfonated poly(arylene ether sulfone)"”.
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Solution-casting of Disulfonated Poly(arylene ether sulfone) Multiblock Copolymer Films for Proton Exchange Membranes
… on the final morphology and properties of disulfonated poly(arylene ether sulfone) multiblock copolymer films from the viewpoint of phase separation of block copolymers. Of equal importance to this work, is a possibility of utilizing a rheological technique for monitoring the transformation …
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Synthesis, crosslinking and characterization of disulfonated poly(arylene ether sulfone)s for application in reverse osmosis and proton exchange membranes
… were developed by synthesis and crosslinking of disulfonated biphenol-based poly (arylene ether sulfone)s (BPS). Crosslinking is a prospective option to reduce the water swelling and improve the dimensional stability of hydrophilic BPS copolymers. Several series of controlled molecular weight, …
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Synthesis and Characterization of Disulfonated Poly(Arylene Ether Sulfone) Random Copolymers as Multipurpose Membranes for Reverse Osmosis and Fuel Cell Applications
… on the synthesis and utilization of several disulfonated poly(arylene ether) random copolymer membranes in fuel cell and reverse osmosis applications. Poly(arylene ether)s were prepared by direct step copolymerization using a third monomer 3,3–-disulfonated 4,4–-dichlorodiphenylsulfone. The …
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Synthesis and Characterization of Hydrophilic-Hydrophobic Disulfonated Poly(Arylene Ether Sulfone)-Decafluoro Biphenyl Based Poly(Arylene Ether) Multiblock Copolymers for Proton Exchange Membranes (PEMs)
Hydrophilic/hydrophobic block copolymers as proton exchange membranes (PEMs) has become an emerging area of research in recent years. Three series of hydrophilic/hydrophobic, fluorinated/sulfonated multiblock copolymers were synthesized and characterized in this thesis. These copolymers were …
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Polymeric and Polymer/Inorganic Composite Membranes for Proton Exchange Membrane Fuel Cells
… Nafion, the current perfluorosulfonic acid copolymer benchmark membrane for both DMFCs and hydrogen/air fuel cells, shows very high methanol crossover. Directly copolymerized disulfonated poly(arylene ether sulfone)s copolymers doped with zirconium phosphates and phenyl phosphonates were …
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Synthesis and Characterization of Hydrophobic-Hydrophilic Segmented and Multiblock Copolymers for Proton Exchange Membrane and Reverse Osmosis Applications
… focused on the synthesis and characterization of disulfonated poly(arylene ether sulfone) hydrophilic-hydrophobic segmented and multiblock copolymers for application as proton exchange membranes (PEMs) in fuel cells or as reverse osmosis (RO) membranes for water desalination. The first objective …
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The Influence of Aromatic Disulfonated Random and Block Copolymers' Molecular Weight, Composition,and Microstructure on the Properties of Proton Exchange Membranes for Fuel Cells
The purity of the disulfonated monomer, such as 3,3"-disulfonated-4,4"-dichlorodiphenyl sulfone (SDCDPS), was very important for obtaining high molecular weight copolymers and accurate control of the oligomer's molecular weight. A novel method to characterize the purity of disulfonated monomer, …
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Synthesis and Characterization of Hydrophilic-Hydrophobic Poly (Arylene Ether Sulfone) Random and Segmented Copolymers for Membrane Applications
Poly(arylene ether sulfone)s are high-performance engineering thermoplastics that have been investigated extensively over the past several decades due to their outstanding mechanical properties, high glass transition temperatures (Tg), solvent resistance and exceptional thermal, oxidative and …
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Synthesis and Characterization of Multiblock Copolymer Proton Exchange Membranes for High Temperature Fuel Cell Applications
… In this dissultation, novel multiblock copolymers based on disulfonated hydrophilic-hydrophobic multiblocks were synthesized and investigated for their potential application as PEMs. The relationship between copolymer chemical composition and resulting properties was probed with a variety …
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Solid-State NMR Studies of Polymeric and Biomembranes
… of ssNMR, with particular emphasis on uses in polymeric and biosciences. First, dynamics investigations on two polymers will be discussed: (1) disulfonated poly(arylene ether sulfone)s /poly(ethylene glycol) blends (BPS-20_PEG), which are under development as chlorine-resistant reverse osmosis …
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High Temperature Polymers for Proton Exchange Membrane Fuel Cells
… PEM fuel cells. The need for thermally stable polymers immediately suggests the possibility of heterocyclic polymers bearing appropriate ion conducting sites. Accordingly, monomers and random disulfonated poly(arylene ether) copolymers containing either naphthalimide, benzoxazole or …
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Morphological and Structure-Property Analyses of Poly(arylene ether sulfone)-Based Random and Multiblock Copolymers for Fuel Cells
… uptake, and proton conductivities of random copolymers. Changes in block length, however, have a pronounced effect on multiblock copolymers, affecting surface and bulk morphologies, water uptake, proton conductivity, and hydrolytic stability, suggesting that multiblock copolymer PEM properties …
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High Performance Disulfonated Poly(arylene Sulfone) Co- and Terpolymers For Proton Exchange Membranes For Fuel Cell And Transducer Applications: Synthesis, Characterization And Fabrication Of Ion Conducting Membranes
… Direct aromatic nucleophilic substitution polycondensations of disodium 3,3′ S-disulfonate-4,4′ S-difluorodiphenylsulfone (SDFDPS), 4,4′ S-difluorodiphenylsulfone (DFDPS) (or their chlorinated analogs, SDCDPS, DCDPS) and 4,4′ S-thiobisbenzenethiol (TBBT) in the presence of potassium …
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Synthesis and Characterization of Multiblock Copolymers for Proton Exchange Membrane Fuel Cells (PEMFC)
… hydrophilic-hydrophobic multiblock copolymers are promising proton exchange membrane (PEM) materials due to their ability to form various morphological structures which enhance transport. Four arylene chlorides monomers (2,5-Dichlorobenzophenone and its derivatives) were first …
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Synthesis and Characterization of Sulfonated Poly(arylene ether sulfone)s for Membrane Separations
Sulfonated poly(arylene ether sulfone)s are a class of engineering thermoplastics well-known for their mechanical properties and chemical/oxidative stability. The research in this dissertation focuses on modifying the structure of sulfonated poly(arylene ether sulfone)s to improve membrane …
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Gas Transport in Proton Exchange Membranes for use in Fuel Cell Applications
… of proton exchange membranes (PEM), namely disulfonated poly(arylene ether sulfone) (BPSH-35), post sulfonated diels-alder poly(phenylene) (SDAPP), and poly(perfluoro sulfonic acid) (Nafion). The O2 gas permeabilities were found to be lower in BPSH and SDAPP as compared to poly(perfluoro …
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NMR Applications in Soft Materials Science: Correlation of Structure, Dynamics, and Transport
… investigation of structure and dynamics of three polymeric membranes: hydroxyalkyl-containing imidazolium homopolymers, poly(arylene ether sulfone) segmented copolymers, and disulfonated poly(arylene ether sulfone) random copolymers using a wide array of SSNMR techniques, including: 1) ¹³C …
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Effect of Backbone Structure on Membrane Properties for Poly(arylene ether) Random and Multiblock Copolymers
Poly(arylene ether)s are a well-established class of thermoplastics that are known for their mechanical toughness, thermal stability, and fabrication into membranes. These materials can undergo a myriad of modifications including backbone structure variability, sulfonation, and crosslinking. In …
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Melt Processable Poly(acrylonitrile)-based Precursors for Carbon Fiber Production and Advanced Polymeric Membranes for Gas Separation and Water Electrolysis Applications
… the feasibility of achieving melt-processable polyacrylonitrile copolymer system precursors for producing high modulus carbon fibers is detailed. High molecular weight poly(acrylonitrile-ran-methyl acrylate) (PAN-MA) copolymer with high acrylonitrile content were mixed with various water …
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Synthesis and Characterization of Hydrophobic-Hydrophilic Multiblock Copolymers for Proton Exchange Membrane Applications
… separated hydrophilic-hydrophobic block copolymer ionomers are believed to be desirable for this purpose Three series of hydrophobic/hydrophillic, partially fluorinated/sulfonated multiblock copolymers were synthesized and characterized in this thesis. The hydrophilic blocks were based upon …