• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.309-309
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• 2006

Latest developments on hybrid nanostructured materials fabricated by applying self-assembly strategies on organic/inorganic nanotemplates are discussed. Within this frame, numerous functional nanomaterials including arrays of composite metal/semiconductor nanoparticles, planar waveguides and functional multilayer thin films are generated using self-assembled polymers as templates or building blocks. In particular, surface plasmon resonance based optical sensing is employed to investigate nanofabrication processes occurring in nanoscale dimention. We also suggest unprecedented pathways to hybrid supramolecular multilayer nanoarchitectures in 1D or 2D geometry via layer-by-layer self-assembly.

• Carbon letters
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• v.28
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• pp.111-115
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• 2018

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3845-3848
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• 2012

• Polymer(Korea)
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• v.29 no.4
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• pp.385-391
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• 2005

Reactive melt processing has been carried out to investigate crosslinking characteristics of high density polyethylene OTDPE) with dicummyl peroxide (DCP) and perbutyle peroxide (PBP). The increase of torque in the internal mixer indicated that the crosslinking in HDPE has been occurred by peroxides. As a result, the substantial decrease of density, melting temperature, and melt enthalpy were found while the melt viscosity increased in partially crosslinked HDPE. In the mechanical properties of partially crosslinked HDPE, the increase of maximum strength and the decrease in elongation at break were clearly noticed and these were more pronounced when PBP was applied as a crosslinking agent. It seems that the maximum strength was obtained with reactive processing temperature at $150^{circ}C$, however, the mixing time did not affect to the strength of partially crosslinked HDPE.

• Polymer Science and Technology
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• v.24 no.1
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• pp.3-9
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• 2013

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.6
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• pp.405-411
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• 2012

The spontaneous axon regeneration of damaged neurons is limited after spinal cord injury (SCI). Recently, mesenchymal stem cell (MSC) transplantation was proposed as a potential approach for enhancing nerve regeneration that avoids the ethical issues associated with embryonic stem cell transplantation. As SCI is a complex pathological entity, the treatment of SCI requires a multipronged approach. The purpose of the present study was to investigate the functional recovery and therapeutic potential of human MSCs (hMSCs) and polymer in a spinal cord hemisection injury model. Rats were subjected to hemisection injuries and then divided into three groups. Two groups of rats underwent partial thoracic hemisection injury followed by implantation of either polymer only or polymer with hMSCs. Another hemisection-only group was used as a control. Behavioral, electrophysiological and immunohistochemical studies were performed on all rats. The functional recovery was significantly improved in the polymer with hMSC-transplanted group as compared with control at five weeks after transplantation. The results of electrophysiologic study demonstrated that the latency of somatosensory-evoked potentials (SSEPs) in the polymer with hMSC-transplanted group was significantly shorter than in the hemisection-only control group. In the results of immunohistochemical study, ${\beta}$-gal-positive cells were observed in the injured and adjacent sites after hMSC transplantation. Surviving hMSCs differentiated into various cell types such as neurons, astrocytes and oligodendrocytes. These data suggest that hMSC transplantation with polymer may play an important role in functional recovery and axonal regeneration after SCI, and may be a potential therapeutic strategy for SCI.

• Macromolecular Research
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• v.17 no.5
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• pp.285-288
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• 2009

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.225-230
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• 1995

Concrete structures need repair and rehabilitation due to functional deficiencies such as cracks, scaling and spalling. Loss of section such as spalling is caused by corrosion of reinforcing bar, fire, temperature change, poor design and etc. This study aims to examine the characteristics of polymer(epoxy)and polymer-cement(latex) for repair materials and to provide the proper repair scheme through static and fatigue tests. Totally 12 beams were tested. Results from static and fatigue tests of beams repaired with polymer and polymer-cement were compared.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.110-111
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• 2006

Most applications of polymers involve blends and mixtures of components including solvents, surfactants, copolymers, fillers, organic or inorganic functional additives, and various processing aids. These components provide unique properties of polymeric materials even beyond those tailored into the basic chemical structures. In addition, skillful processing extends the properties for even greater applications. The perennial challenge of polymer science is to understand and exploit the structure-processing-property interplay relationship. We are developing and demonstrating combinatorial methods and high throughput analysis as tools to provide this fundamental understanding.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.123-124
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• 2006

Ionic liquids (ILs) are collecting keen interests as an advanced substituent of electrolyte solution as well as novel solvents. In the present talk, I will introduce some strategies to fix IL structure on polymer chains to prepare polar polymers with low glass transition temperature. Namely, cationic, anionic, and zwitterionic monomers have been prepared, and they have been homopolymerized or copolymerized to prepare polymer electrolytes with different properties. The polymers themselves showed very poor ionic conductivity, but it was improved by suitable spacer between charged site and main chain. Other unique characteristics of functional ILs and new polymerized ionic liquids will also be mentioned.