• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.327-329
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• 2008

We have studied the optically compensated splay (OCS) mode using reactive mesogen monomer to reduce critical voltage, setting voltage and phase transition time from initial bend to splay state. The high pretilt angle from vertical alignment was formed through the polymerization of UV curable RM monomer at the surfaces. In this way, orientation of the LC with OCS can be achieved without setting voltage.

• Macromolecular Research
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• v.11 no.3
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• pp.194-197
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• 2003

A new 2,5-di(t-octylphenoxy) group substituted poly(p-phenylenevinylene) derivative was synthesized by Gilch polymerization. The obtained polymer was characterized by NMR, FT-IR, and chemical analysis and completely soluble in common organic solvents. The polymer showed good thermal stability with T$_{g}$ of 105$^{\circ}C$. The polymer dissolved in chloroform showed maximum emission at 514 nm with a shoulder peak at around 560 nm. The EL spectrum of the ITO/PEDOT/TOP-PPV/Al device was observed maximum emission at 545 nm with a shoulder peak at around 585 nm.m.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.3
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• pp.15-20
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• 2016

In an effort to overcome the weakness of aerogel, polymer aerogels have been prepared by copolymerizing the different types of monomers through sol-gel process. Polymerizing the successive phase of a high internal phase emulsion, which has interconnected porous structure, porous polymer aerogel can be manufactured. In this paper, we use the styrene/divinylbenzene chain as a basic monomer structure, and additionally use 2-ethylhexyl methacrylate (2-EHMA) or 2-ethylhexyl acrylate (2-EHA) as monomers for distinguishing the visible mechanical properties of synthesized polymer aerogel. We can observe the different tendency of polymer aerogels by kinds of monomer or ratio. Flexibility and microstructure can be changed by the types of monomer. EHA polymer aerogel shows high flexibility and thin microstructure, and EHMA polymer aerogel shows high hardness and thick microstructure. EHA/EHMA polymer aerogel shows the intermediate nature between them. By utilizing the mechanical properties of three types of polymer aerogels to adequate situation or environment, polymer aerogels could be used as drug agent, ion exchange resin, oil filter and insulator, and so on.

• Macromolecular Research
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• v.14 no.2
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• pp.173-178
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• 2006

Poly(3-(2-hydroxyethyl)thiophene) (P3HET) was synthesized using oxidative coupling polymerization that involved the protecting and deprotecting of hydroxyl groups but not the chlorine substitution or oxidative decomposition of the hydroxyl groups. The resulting P3HET exhibited good solubility in aprotic solvents, in contrast to the insoluble polymer product synthesized directly from the monomer, 3-(2-hydroxyethyl)thiophene (3HET). P3HET had low conductivity due to the strong hydrogen bonding of its hydroxyl groups. The ester-functionalized poly(3-(2-acetoxyethyl)thiophene) and poly(3-(4-pentylbenzoateethyl)thiophene) were also prepared with reasonably high molecular weights in order to examine how this functionalization modified the physical and chemical properties of P3HET. These polymers exhibited better solubility in common solvents and higher conductivity than P3HET. All these polymers exhibited bathochromic shifts of their film state absorption maxima with respect to those found in the UV-visible spectra of their solution phases. The extent of the bathochromic shift was found to vary with the lengths of the side chains of the ester-functionalized polymers.

• Korean Membrane Journal
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• v.11 no.1
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• pp.8-14
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• 2009

The sulfonated poly(styrene-divinylbenzene-acrylonitrile) (ST-DVB-AN) composite polymer electrolyte membrane based on the original PVC film was successfully synthesized to improve oxidative stability using semi-interpenetrated polymer network (semi-IPN). Weight gain ratio after copolymerization was enhanced by the DVB and AN contents, and the sulfonated membranes were characterized in terms of proton conductivity (k), ion exchange capacity (IEC), and water uptake ($W_U$). The effect of DVB content and AN addition were thoroughly investigated by comparing the resulted properties including oxidative stability. The obtained ST-DVB-AN composited semi-IPN membranes showed relatively high proton conductivity and IEC compared with Nafion117, and greatly improved oxidative stability of the synthesized membrane was obtained. This study demonstrated that a semi-interpenetrated sulfonated ST-DVB-AN composited membrane reinforced by PVC polymer network is a promising candidate as an inexpensive polymer electrolyte membrane for fuel cell applications.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.91-92
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• 2006

The fine-tuned dendrons provide unique supramolecular self-assemblies in various environments such as in water, organic media, and solid-liquid interfaces. They form nanotubes, vesicles, thin films, columns, lamellar nanoribbons depending on the condition of self-assembly process. Unique characteristics of self-assembly of the amide dendrons are described. In addition, elucidation of the structural correlation between the building blocks and the assemblies, stabilization of assembled structure, and transformation of supramolecular assemblies by using external stimuli. Particular emphasis is placed on the formation of cyclodextrin-covered organic nanotubes derived from self-assembly of amide dendrons and their supramolecular transformation. Finally, unique biosensory characteristics of the self-assembled nanotubes will be discussed.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.90-90
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• 2006

Mesogen-Jacketed Liquid Crystalline Polymers, MJLCPs, are polymers with mesogenic side groups directly attached to main-chains without using flexible connecting spacers and are able to form liquid crystalline structures. Later work on structure-property of the polymers revealed that the side groups are not necessarily mesogenic for the polymers to form a mesophase so long as that the side groups are directly attached to the backbones and the side groups are large enough. Because of its inherent chain stiffness and that the monomers of MJLCPs are readily polymerizable by "living" free radical polymerizations, MJLCP offered a unique handy tool for making block copolymers. In addition, MJLCP offered also new opportunities for novel functional materials.

• Macromolecular Research
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• v.17 no.5
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• pp.352-355
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• 2009

• Polymer Science and Technology
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• v.25 no.3
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• pp.214-231
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• 2014

• Polymer Science and Technology
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• v.19 no.6
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• pp.512-529
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• 2008