Kwak S-Y – Page 2 – TechConnect Briefs

Preparation and Characterization of Nafion/Microporous Titanosilicate Composite Membranes as Ion-Conducting Materials

Ryu S.-Y., Jeon J-D, Kwak S-Y, Seoul National Univesity, KR

Nafion is currently the most frequently used polymeric electrolyte in membranes for many fuel cell applications. Direct methanol fuel cells this electrolyte membrane are currently being considered as a desirable electrochemical power source in potable [...]

Characterization on Dioxin Emission of TiO2 Nanoparticle-Encapsulating Poly(vinyl chloride) (TEPVC) compared to conventional PVC

Yoo H., Kim S-H, Lee A.R., Kwak S-Y, Seoul National University, KR

In our previous study, we first prepared TiO2 nanoparticle-encapsulating poly(vinyl chloride) (TEPVC) aiming at breakthrough to enhance the dispersibility of TiO2 nanoparticles in PVC matrix to maximize catalytic activities of TiO2 nanoparticles. The present study [...]

Novel Supramolecules Based on Architecturally Variant alpha-Cyclodextrin Polyrotaxanes and Nanorod-Like alpha-Cyclodextrin Self-Assembly

Chung J.W., Yu B.-Y., Kwak S-Y, Seoul National University, KR

Self-assembly (SA-ICs) of architecturally variant alpha-cyclodextrin (alpha-CD) inclusion complexes (ICs) formed by host-guest reaction with four polymeric guest having different molecular architectures (star-shaped, hyperbranched, diblocked, and linear polymer) and nanorod-like self-assembly (SA-CD) of alpha-CD could [...]

Synthesis and Characterization of a Series of Star-Branched Poly(epsilon-caprolactone)s with Nanoscale Molecular Architectural Variation

Choi J., Song H.J., Kwak S-Y, Seoul National University, KR

In this study, a series of star-branched poly(epsilon-caprolactone)s (SPCLs) was synthesized with nanoscale molecular architectural variation in arm numbers and lengths by ring-opening polymerization under bulk condition. Arm numbers were varied to be 3, 4, [...]

Viscoelastic Relaxation and Molecular Mobility of Hyperbranched Poly(epsilon-caprolactone)s in Their Melt State

Song H.J., Choi J., Kwak S-Y, Seoul National University, KR

The dynamic viscoelastic relaxation behavior and the molecular mobility of hyperbranched poly(epsilon-caprolactone)s (HPCLs) possessing the molecular architectural variation and their linear counterpart, linear poly(epsilon-caprolactone) (LPCL), were characterized and evaluated in conjunction with their specific molecular [...]

Effects of the Addition of TiO2 Nanoparticles for Polymer Electrolytes Based on Porous Poly(vinylidene fluoride-co-hexafluoropropylene)/Poly(ethylene oxide-co-ethylene carbonate) Membranes

Jeon J-D, Kim M-J, Chung J.W., Kwak S-Y, Seoul National University, KR

In order to ameliorate the performance of polymer electrolytes, we report on a novel solvent-free polymer electrolyte filled with viscous poly(ethylene oxide-co-ethylene carbonate) (P(EO-EC)) into a porous membrane. In addition, to enhance the conductivity and [...]

Evaluation of the Degree of Exfoliation in Poly(epsilon-caprolactone) Nanocomposites Using by the Dynamic Mechanical Analysis

Chung J.W., Jeon J-D, Kwak S-Y, Seoul National University, KR

Nanocomposites composed of poly(epsilon-caprolactone) (PCL) and the organoclays which were layered silicate with the organic modifiers, i.e., nonpolar (OC25A) and polar (OC30B), were prepared by melt mixing. After mixing, we imposed additional heat to PCL/organoclay [...]