• 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.

• Carbon letters
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• v.5 no.2
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• pp.68-74
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• 2004

The polymer with contents of $C_{60}$ up to 57 wt.% was produced by mutual condensation of fullerene $C_{60}$ and ethylenediamine. The investigations of this polymer as well as pristine fullerene to comparison were carried out by FT-IR and UV-Vis spectroscopy, ToF-SIMS, TGA, and elemental analysis. At least three kinds of components was revealed as building blocks of polymer. The fullerene cage underwent only distortion but didn't destroy during formation of polymer. The pure fullerene was found as an intermediate of the thermal decomposition of polymer. The conclusion that this polymer could serve as precursor to produce carbon nanomaterial with high concentration curved graphene sheets and can be used for gas adsorption and electrochemical application was made.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.695-698
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• 2004

Recently, the usage of polymer concrete mortar gathering an interest as a new construction material rapidly increases inside and outside of the country because it is an environment-friendly and endurable material. However, up to these days, the researches about the polymer composite have not been satisfactorily conducted. The polymer concrete is superior to the general cement materials in the properties of strength and durability while it is inferior in elastic modulus. Because that the members using the polymer concrete have therefore higher strength and ductility than the members of general cement concrete, an analysis equation of high-strength cement concrete can be referenced but it is not applied for the researches about the polymer concrete members. In this study, the flexural properties of T-shaped beam of the steel- and GFRP-reinforced polymer concrete are analyzed to examine the suggested analysis equation. Results of this experimental researches are to be used as the basic data in a structural design of the polymer concrete.

• Journal of the Korean Graphic Arts Communication Society
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• v.11 no.1
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• pp.71-84
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• 1993

Practically to put use high-photosensitive polymer, poly(vinyl cinnamoyl acetate), we investigated and confirmed UCHIDA`s synthesis, according to control solvent, which is the esterification of poly (vinyl alcohol) with monochloroacetic acid and can be freely conrolled the successive cinnamoyl acetoxyl esterfication of PVCiA, and intruducing photosensitizers,studied the photosensitivity of PVCiA.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.462-463
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• 2003

With Fixate$^{TM}$ G-100 polymer, a whole new world of styling product possibilities awaks you. Fixate$^{TM}$ G-100 polymer satisties the demand for high performance products that offer significant consumer perceptible benefits, while meeting the tormulator's needs for cost control and manufacturing efficiency.(omitted)ted)

• Polymer Science and Technology
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• v.8 no.2
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• pp.169-174
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• 1997

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.159-160
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• 2022

The purpose of this study is to evaluate the adhesion in flexure depending on the cement type, polymer type, polymer-cement ratio, and silica fume ratio of the polymer-cement composites(PCCs) for crack repair in RC structures to induce optimal mix proportions. The adhesion in flexure of PCCs for crack repair of RC structure has a significant effect on the polymer type and polymer-cement ratio, and the adhesion in flexure is generally improved with mixing of silica fume as a mixture. The adhesion in flexure according to the type of polymer is slightly higher in the order of SAE, EVA, and SBR, and it is relatively high at the polymer-cement ratio of 60% or 80%. In addition, the adhesion in flexure of PCCs with silica fume ratio of 10% or 20% to the cement weight is higher than that without silica fume. In order to improve the adhesion in flexure of PCCs for repairing cracks in RC structures, the optimal mix design is to properly adjust the cement type, polymer type, polymer-cement ratio, and silica fume ratio.

• Transactions of Materials Processing
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• v.17 no.8
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• pp.633-642
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• 2008

It's important to measure quantitative properties about thermal-nano behavior of polymer for producing high quality components using Nanoimprint lithography process. Nanoscale indents can be used to make the cells for molecular electronics and drug delivery, slots for integration into nanodevices, and defects for tailoring the structure and properties. In this study, formability of polymethylmetacrylate(PMMA) and polycarbonate(PC) were characterized Polymer has extreme variation in thermo mechanical variation during forming high temperature. Because of heating the polymer, it becomes softer than at room temperature. In this case it is particularly important to study high temperature-induced mechanical properties of polymer. Nanoindenter XP(MTS) was used to measure thermo mechanical properties of PMMA and PC. Polymer was heated by using the heating stage on NanoXP. At CSM(Continuous Stiffness Method) mode test, heating temperature was $110^{\circ}C,120^{\circ}C,130^{\circ}C,140^{\circ}C$ and $150^{\circ}C$ for PMMA, $140^{\circ}C,150^{\circ}C,160^{\circ}C,170^{\circ}C$ and $180^{\circ}C$ for PC, respectively. Maximum indentation depth was 2000nm. At basic mode test, heating temperature was $90^{\circ}C$ and $110^{\circ}C$ for PMMA, $140^{\circ}C,160^{\circ}C$ for PC. Maximum load was 10mN, 20mN and 40mN. Also indented pattern was observed by using SEM and AFM. Mechanical properties of PMMA and PC decreased when temperature increased. Decrease of mechanical properties from PMMA went down rapidly than that of PC.

• Polymer(Korea)
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• v.32 no.4
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• pp.313-321
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• 2008

Acrylic pressure sensitive adhesive(PSA) was prepared by UV radiation curing and the peel energy and physical properties of PSA were investigated. The increase of amount of acrylic acid leads to improve the peel energy, associated with the substrate having smooth surface and high layer thickness. The high peel energy is obtained when the direction of irregularity in substrate is horizontal with the peeling direction. This is attributed to the increase of resistance to peeling in spite of decrease of wetting and the result corresponds to our supposition.

• Korea-Australia Rheology Journal
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• v.18 no.2
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• pp.83-90
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• 2006

Supercritical carbon dioxide ($scCO_2$) has advantages of being incorporated in polymer with high solubility and of being recovered easily by depressurizing. $scCO_2$ reduces the viscosity of polymer melt and it is expected to be use as a plasticizing agent. In this work, we studied on the effect of $scCO_2$ on the rheological properties of polymer melts during extrusion process. Slit die attached to twin screw extruder was used to measure the viscosity of polymer melts plasticized by supercritical $CO_2$. A gas injection system was devised to accurately meter the supercritical $CO_2$ into the extruder barrel. Measurements of pressure drop within the die, confirmed the presence of a one phase mixture and a fully developed flow during the measurements. The viscosity measurement of polypropylene was performed at experimental conditions of various temperatures, pressures and $CO_2$ concentrations. We observed that melt viscosity of polymer was dramatically reduced by $CO_2$ addition.