• Polymer(Korea)
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• v.26 no.1
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• pp.1-8
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• 2002

In this study, poly(arylene ether sulfone) (PAES) having thermal stability and excellent mechanical properties was synthesized to be useful for the matrix of anion exchange resin. $1^{\circ}$-Aminated poly(arylene ether sulfone) ($1^{\circ}$-APAES) was prepared by reduction reaction after lithiation of PAES. Then $3^{\circ}$-APAES was Prepared by alkylation of the amino group of $1^{\circ}$-APAES. The structures of PAES and APAESs were confirmed with FT-IR and $^1H-NMR$ spectroscopy. Also, thermal properties of the resins were characterized by DSC and TG analysis. The introduction of amine groups in PAES resulted in the increase of glass transition temperature and decrease of initial thermal degradation temperature. The ion exchange capacities of $1^{\circ}$-APAES and $1^{\circ}$-APAES were 1.19 and 1.45 meq/g, respectively.

• Macromolecular Research
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• v.13 no.6
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• pp.514-520
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• 2005

Composite membranes of Nafion and sulfonated poly(arylene ether sulfone) were prepared. Sulfonated poly(arylene ether sulfone)s with different degrees of sulfonation were blended with Nafion to reduce the methanol crossover. The morphology, proton conductivity and methanol permeability of the resulting composite membranes were investigated by SEM, EDAX, AC impedance spectroscopy and permeability measuring instrument. The cross­sections of the composite membranes showed a phase separated morphology. The morphology and phase separation mechanism could be controlled by varying the blend ratio and the degree of sulfonation of poly(arylene ether sulfone). These complex morphologies can be applied for reducing methanol crossover. The methanol permeability and proton conductivity of the composite membranes were lower than those of Nafion 117 membrane since the development of an ionic pathway in the blend membrane was more difficult than that in Nafion itself.

• Membrane Journal
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• v.22 no.3
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• pp.191-200
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• 2012

New composite membranes were manufactured by impregnating post-sulfonated poly(arylene ether sulfone)s containing perfluorocyclobutane (PFCB) groups into porous polytetrafluoroethylene (PTFE) films. Two kinds of post-sulfonated poly(arylene ether sulfone)s with two different monomer ratios (sulfonable biphenylene monomer : non-sulfonable sulfonyl monomer = 6 : 4, 4 : 6) were first prepared through three synthetic steps: synthesis of trifluorovinylether-terminated monomers, thermal cycloaddition polymerization and post-sulfonation using chlorosulfonic acid (CSA). The composite membranes were then prepared by adjusting the concentrations (5~20 wt%) of the resulting copolymers impregnated in the PTFE films. The water uptake, ion exchange capacity (IEC) and ion conductivity of the composite membranes were characterized and compared with their unreinforced dense membranes and Nafion. All the synthesized compounds, monomers and polymers were characterized by $^1H$-NMR, $^{19}F$-NMR and FT-IR and the composite membranes were observed with scanning electron micrographs (SEM).

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.671-676
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• 2013

Recently, there are many efforts focused on development of Redox Flow Battery (RFB) for large energy storage system. Economical hydrocarbon membranes alternative to fluorinated membranes for RFB membrane are receiving attention. In this study, characteristics of poly(arylene ether sulfone) (PAES) were compared with expensive fluorinated membrane at VRB (Vanadium Redox Flow Battery) operation condition. Permeability of vanadium ion through membrane, ion exchange capacity (IEC), change of OCV, swelling, charge-discharge curves and energy efficiency were measured. PAES membrane showed lower permeability of vanadium ion, higher IEC and then higher energy efficiency compared with Nafion 117 membranes.

• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.556-560
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• 2013

Recently, there are many efforts focused on development of more economical non-fluorinated membranes for use in PEMFCs (Proton Exchange Membrane Fuel Cells). In this study, characteristics of poly(arylene ether sulfone)(PAES) were compared with fluorinated membrane at PEMFC operation condition. I-V polarization curve, hydrogen crossover, electrochemical surface area, membrane resistance and charge transfer resistance were measured. PAES membrane showed similar performance compared with fluorinated membrane at 100% relative humidity, but the performance of PAES membrane decreased largely due to low ionic conductivity at low relative humidity.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.11a
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• pp.165-166
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• 2004

• Membrane Journal
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• v.27 no.2
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• pp.182-188
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• 2017

Sulfonated poly(arylene ether sulfone) (SPAES)-3-mercaptopropyl silica gel (3MPTSG) composite membranes with improved oxidative stability were prepared for polymer electrolyte fuel cell application. It has been reported that ether part of main chain of aromatic hydrocarbon based membranes were weak to radical attack to decrease membrane durability. In this study, the hydrophilic inorganic particles were introduced by minimizing a decrease in ion conductivity and increasing an oxidative stability. The composite membranes were investigated in terms of ionic conductivity, ion exchange capacity (IEC), FT-IR, TGA and contact angle, etc. As a result, increasing amount of the 3MPTSG resulted in decrease in proton conductivities and water uptakes at 100% R.H. but enhanced thermal and oxidative stabilities.

• Composites Research
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• v.12 no.4
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• pp.55-61
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• 1999

Interfacial shear strength (IFSS) of poly(arylene ether phosphine oxide) (PEPO) coated carbon fibers was evaluated via microdroplet test and compared with results obtained from carbon fibers coated with poly(arylene ether sulfone) (PES), Udel$^{\circledR}$ P-1700 and Ultem$^{\circledR}$ 1000. Interfacial adhesion between thermoplastics and uncoated carbon fibers was also measured in order to understand the adheion mechanism. PEPO coated carbon fibers showed the highest IFSS, followed by PES, Udel and Ultem coated fibers. A similar trend was observed for thermoplastic/uncoated fibers. SEM analysis indicated that only PEPO coated fiber exhibited cohesie failure in the vinylester resin, while others showed failure at or near the interface of polymer coating and vinylester resin. The enhanced interfacial adhesion by PEPO coating could be attributed to the strong interaction of P = 0 moiety to the fiber as well as to the vinylester resin.

• Journal of the Korean Electrochemical Society
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• v.18 no.2
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• pp.75-80
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• 2015

Multi-block sulfonated poly(arylene ether sulfone) (SPAES) copolymer was synthesized via nucleophilic aromatic substitution reaction for proton exchange membrane fuel cell application. After synthesizing the hydrophilic and hydrophobic precursor oligomers having different end-groups (F-terminated or OH-terminated), the effect of end group on the molecular weight was investigated. Hydrophilic oligomers with hydroquinone showed better performance as fuel cell membranes. SPAES membranes showed comparable proton conductivity to that of Nafion at $80^{\circ}C$ and above 70% RH. In particular, SPAES 9 with hydroquinone showed higher proton conductivity than SPAES 10 in the whole RH range studied. Increased local concentration of sulfonic acids within hydrophilic block might develop the hydrophilic-hydrophobic phase separation in the block copolymers.

• Membrane Journal
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• v.21 no.1
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• pp.1-12
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• 2011

Partially fluorinated poly(arylene ether sulfone) block ionomer membranes with different branch degree for fuel cell applications were investigated. A sulfonable monomer, a non-sulfonable monomer and a trifunctional branching agent were synthesized and the sulfonable monomer was oligomerized to obtain block structures. The oligomer was then further polymerized with the non-sulfonable monomer and the branching agent. The mole ratio of oligomer : non-sulfonable monomer was fixed at 4:6 and the content of the branching agent was varied from 0 to 2 mol% (BBC-40Bx). Post-sulfonation of BBC-40Bx was carried out using chlorosulfonic acid (CSA) (SBBC-40Bx). All the synthesized compounds were characterized by $^1H$-NMR, $^{19}F$-NMR and FT-IR. It was confirmed that the ion exchange capacity (IEC), water uptake and ion conductivity of SBBC-40Bx increased with the increment of branching agent content.