Yong‐Jin Choi

Gwangju Institute of Science and Technology, Gwangju, Gwangju, South Korea

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Publications (2)3.98 Total impact

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    ABSTRACT: A poly(vinyl chloride) (PVC)/glycidyl methacrylate (GMA)-divinyl benzene (DVB)-based membrane was prepared via monomer sorption, and then pyridium or its derivates (that is, 4-ethyl pyridium, 4-tetrabutyl pyridium) were introduced into the PVC/poly(GMA-DVB) base membrane. The effects of pyridinium anion-exchangeable sites on the water splitting and the electrochemical properties of the membrane were investigated. The electrochemical properties and the water splitting on the anion-exchange membranes were compared with selected commercial membranes containing quaternary ammonium groups. The pyridium membranes showed good electrochemical properties, comparable to those of the commercial membranes, with electrical resistances of less than 3.0 × 10−4 Ω·m2 in 0.5 mol dm−3 NaCl and high ionic permselectivities (the transport number of Cl− ions being 0.96). Moreover, water splitting indicated by the proton transport numbers of the membranes containing pyridinium or its derivates, were about two or three orders of magnitude lower than those of the commercial membranes (such as AM-1) at the same current density because the resonance effect in the quaternary pyridinium groups contributed to their molecular stability.
    AIChE Journal 04/2004; 49(12):3213 - 3220. · 2.58 Impact Factor
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    ABSTRACT: Polystyrene cation exchange membranes were prepared by a PVC-based semi-interpenetrating polymer network (IPN) method. The reaction behaviors during polymerization and sulfonation in the preparation method were investigated. The prepared membranes were characterized in terms of the physical and electrochemical properties. The membranes exhibited reasonable mechanical properties (tensile strength, 13 MPa, and elongation at break, 52%) for an ion-exchange membrane with the ratio of polystyrene–divinylbenzene (DVB)/poly(vinyl chloride) (PVC) (RSt-DVB/PVC) of below 0.9. Fourier transform infrared/attenuated total reflectance, differential scanning calorimetry, and scanning electron microscopy studies revealed the formation of a homogeneous membrane. The resulting membrane showed membrane electrical resistance of 2.0 Ω cm2 and ion-exchange capacity of 3.0 meq/g dry membrane. The current–voltage (I–V) curves of the membrane show that the semi-IPN polystyrene membranes can be properly used at a high current density, and that the distribution of cation-exchange sites in the membrane was more homogenous than that in commercial membranes. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1488–1496, 2003
    Journal of Applied Polymer Science 02/2003; 88(6):1488 - 1496. · 1.40 Impact Factor

Publication Stats

14 Citations
3.98 Total Impact Points

Institutions

  • 2004
    • Gwangju Institute of Science and Technology
      • School of Environmental Science and Engineering
      Gwangju, Gwangju, South Korea