• Proceedings of the Membrane Society of Korea Conference
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• 1999.10b
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• pp.49-51
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• 1999

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.544-548
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• 1993

Glass transition temperatures($T_g$) of poly(phenylene sulfide sulfone)[PPSS], which were heat treated at various temperature and time, were studied by DSC. Up to $230^{\circ}C$, $T_g$ of heat treated PPSS were increased with increasing the heat treated time. When the sample was heated at $260^{\circ}C$ for 30 minute and $280^{\circ}C$ for 10 minute, however, $T_g$ of those samples were decreased. These phenomena can be explained by the factors of chain extension reaction, oxidative crosslinking, and thermal crosslinking.

• Membrane Journal
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• v.29 no.3
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• pp.155-163
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• 2019

The anion exchange membrane using the blending polymer of poly(ether sulfone) and poly(phenylene sulfide sulfone) was prepared. It was confirmed by EDXS and FT-IR analysis that the prepared anion exchange membrane had the -N- as an anion exchange group. The ionic conductivity in 1 mol/L $H_2SO_4$ aqueous solution was measured. The ionic conductivity of the prepared anion exchange membrane was 0.015~0.083 S/cm, and had a high value compared with AFN and APS as a commercial anion exchange membrane. Permeabilities of the vanadium ions through the prepared anion exchange membrane were tested to evaluate the possibility as a separator in vanadium redox flow battery. Vanadium ion permeation rate in the prepared anion exchange membrane had a low value compared with Nafion 117 as a commercial cation exchange and AFN as a commercial anion exchange membrane.

• Applied Chemistry for Engineering
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• v.9 no.3
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• pp.440-444
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• 1998

Poly(phenylene sulfide-co-phenylene sulfide sulfone), PPS/PPSS copolymers were synthesized from p-dichlobenzene(DCB), p-dibromobenzene(DBB), p-diiodobenzene(DIB), 4-chlorophenyl sulfone(CPS) and sodium sulfide as comonomers under high temperature and pressure utilizing N-methyl-2-pyrrolidinone(NMP) as solvent. The yield of PPS/PPSS copolymer shoed maximum at $190^{\circ}C$ with [DBB]/[CPS] and [DIB]/[CPS] comonomer pair, while [DCB]/[CPS] pair exhibited maximum yield at $230^{\circ}C$. The change of yield is in the order of I>Br>Cl as leaving groups were in accordance with nucleophilic aromatic substitution reaction mechanism suggested for the synthesis of PPS type polymers. The molecular weight of PPS/PPSS copolymer was the highest($M_w=8,330g/mol$) with [DBB]/[CPS] comonomers in which [CPS] was 10 mole%. The PPS/PPSS copolymer made with 10 mole% of [CPS] showed about $15^{\circ}C$ higher $T_g$ and $15^{\circ}C$ lower $T_m$ than those of PPS homopolymer, which may be useful from the processing and thermal property point of view. The PPS/PPSS copolymer with 30 mole% of CPS or above did not exhibit Tm. The PPS/PPSS copolymer obtained with comonomer feed ratio of [DBB]/[CPS] = 95/5 mole% under $240^{\circ}C$ showed even higher molecular weight($M_w=10,300g/mole$) than PPS homopolymer made under similar reaction condition, retaining high crystallinity and thermal stability.

• Membrane Journal
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• v.10 no.2
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• pp.66-74
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• 2000

In consideration that a high tensile strength and ion exchange capacity are maintained as the swelling of membrane is controlled by the coagulation of PSf with the introduction of ion exchange groups and PPSS without the introduction of ion exchange groups, the block copolymer of PSf and PPSS were synthesized. The cation exchange membrane was prepared by sulfonation with CSA and casted. The synthesized block copolymer and cation exchange membrane were characterized by FT-IR and their thermal stability was confirmed by TGA. The optimum sulfonation could be accomplished at a mole ratio of BPSf to CSA 1:3. The best electrochemical properties obtained by the optimal condition were area resistance of 4.37 $\Omega$ㆍ$\textrm{cm}^2$, ion exchange capacity of 1.71 meq/g dry membrane, water content of 0.2941 g $H_2O$/g dry membrane, and fixed ion concentration of 5.81 meq/g $H_2O$. When GBL was used as an additive, area resistance was increased by 13.7 % and ion exchange capacity was increased by 14.6%. When the membrane was fabricated in a form of composite using non woven cloth as a support. the tensile strength of membrane could be improved, but the electrochemical characteristics were not influenced.

• Proceedings of the Membrane Society of Korea Conference
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• 1991.10a
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• pp.9-16
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• 1991

The current status of reverse osmosis and ultrafiltration membranes are reviewed with the view for the future. In the case of reverse osmosis (RO) membranes, as examples, new crosslinked aromatic polyamide membranes exhibited the superior separation performance with the sufficient water permeability, the high tolerance for oxidizing agents and chemicals. Ultrafiltration (UF) membrane based on poly(phenylene sulfide sulfone) (PPSS) also exibited the superior separation performance with the high solvent, heat and fouling resistance.

• Journal of Hydrogen and New Energy
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• v.16 no.2
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• pp.103-110
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• 2005

Proton conducting solid polymer electrolyte (SPE) membranes have been used in many energy technological applications such as water electolysis, fuel cells, redox-flow battery, and other electrochemical devices. The availability of stable membranes with good electrochemical characteristics as proton conductivity at high temperatures above 80 $^{\circ}C$ and low cost are very important for its applications. However, the presently available perfluorinated ionomers are not applicable because of high manufacturing cost and high temperature use to the decrease in the proton conductivity and mechanical strength. In order to make up for the weak points, the block copolymer (BPSf) of polysulfone and poly (phenylene sulfide sulfone) were synthesized and sulfonated. The electrolyte membranes were prepared with phosphotungstic acid (HPA)/sulfonated BPSf via solution blending. This study would be desirable to investigate the interaction between the HPA and sulfonated polysulfone. The results showed that the characteristics of SPSf/HPA blend membrane was a better than Nafion at high temperature, 100 $^{\circ}C$. These membranes proved to have a high proton conductivity, $6.29{\times}10-2$ S/cm, a water content, 23.9%, and a ion exchange capacity, 1.97 meq./g dry membrane. Moreover, some of the membranes kept their high thermal and mechanical stability.

• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.158-161
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• 2008