• Polymer(Korea)
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• v.34 no.4
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• pp.357-362
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• 2010

Poly(ethyleneglycol diacrylate)(PEGDA) or 2-ethylhexyl acrylate(2EHA)-based gel polymer electrolytes(GPEs) which have a solid content in the range of 8～54 wt% were synthesized and their ionic conductivity and electrochemical properties were measured at room temperature. It was observed that the ionic conductivity over $1\times10^{-3}$ S/cm was obtained in a homogeneous PEGDA-based GPE with 21 wt% of solid content. However the electrochemical stability of the GPE was lower than that of a liquid electrolyte. The presence of AIBN initiator which can produce a N2 gas during polymerization process might be the reason of this low oxidation decomposition potential. As an alternative, benzoyl peroxide was used as an initiator and GPE with enhanced electrochemical stability was obtained. Finally, the formation of stable solid electrolyte interphase on a graphite anode was evidenced by cyclic voltammetry measurement.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.337-340
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• 2008

As the Ready-mixed Shotcrete using Powdered Polymer Dispersion, Shotcrete Matrix as totally shotcrete gel that a part of second binder in Shotcrete materials is dense. Also, Ready-mixed Shotcrete is showed the decreasing Rebound and rising Durability. Therefore, it is possible that Ready-mixed Shotcrete for High-Strength and High-Waterproof can apply to the Powdered Polymer Dispersion.

• Transactions on Electrical and Electronic Materials
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• v.4 no.1
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• pp.11-14
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• 2003

The regularities of immobilization of natural medicinal substances - alchidine on gels of poly(vinyl alcohol) - are investigated. It is shown that the polymer components of alchidine interact with nonionic polymer with formation of interpolymer complexes. The influence of the different factors on the properties of complexes is considered and the constants of alchidine distribution in the system gel - water are calculated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.581-584
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• 2001

For the first time, a totally solid state electric double layer capacitor has been fabricated using an alkaline polymer electrolyte and an activated carbon powder as electrode material. The polymer electrolyte serves both as separator as well as electrode binder. The capacitor has a three-layer structure; electrode-electrolyte-electrode. A cyclic voltammetry and constant current discharge have been used for the determination of the electro chemical performance of capacitors.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.3
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• pp.495-505
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• 2016

This study explores and selects an appropriate material that considers light and soft physical properties as well as activity for impact absorption pads that can be used to develop practical impact protective clothes worn during daily life by the elderly to reduce the impact of falls. Physical properties, impact absorption performance, and compression characteristics were evaluated on 5 types of foam, 2 types of 3D spacer fabric, and 3 types of polymer gel to select a material appropriate for the pad to be inserted into impact protective clothes. The evaluation of the physical properties showed that 3D spacer fabrics had lower density compared to other materials and polymer gels had the highest density. The elongation percentage was higher in foams than 3D spacer fabrics and EPDM foam had the highest elongation percentage. The impact absorption performance of honeycomb polymer gel was better than foams and 3D spacer fabrics. As a result of looking into compression energy and compression characteristics of materials, 'CR foam A' was found to absorb the largest amount of compression energy, 24.1%, among foams and polymer gels. A high energy absorption rate of 50.0% (or above) was indicated by 3D spacer fabrics; however, foams and polymer gels showed a progressive deformation of energy compression / recovery curve with 3D spacer fabrics that showed drastic deformation. Based on characteristics of materials, 'CR foam C' and EPDM with relatively high absorption performance can be used as protective pad materials among foams. Among polymer gels, 2 open-type polymer gels that have relatively low impact protective performance but a relatively lighter weight on human body (compared to closed-type) are considered appropriate protective pad materials.

• Polymer(Korea)
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• v.24 no.4
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• pp.529-537
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• 2000

The effects of the gel content on the cell structures of PP sheets by using an electron-curing system were investigated. Three extruded PP sheets crosslinked by three different doses were used for the batch foaming process with the supercritical state $CO_2$. Experiments were also performed in order to study the effects of the gel content, saturation pressure and temperature on cell structures. Then foaming conditions, such as temperature and duration of time, were changed. The amount of gas absorbed into PP samples was not affected by gel contents and the operating condition of saturation pressure, which was higher than 2000 psi. The foam cells of PP with a low gel content grew irregularly at a higher foaming temperature and for a longer duration of foaming time. However, PP samples with high gel content showed even cell structures and narrow tell size distributions under the severe conditions of high foaming temperatures and long duration of foaming time.

• Macromolecular Research
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• v.11 no.3
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• pp.172-177
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• 2003

Biphenyltetracarboximide-phenylene diamine polyimide/silica-titania ternary hybrid composites were Prepared by thermal imidization and sol-gel reaction. Fluorescence spectroscopic, scanning electron microscopy, and atomic force microscopy studies revealed that the addition of small amount of titania showed profound effects on the microstructure and photophysical behaviors of polyimide/silica hybrid composites, when the content of silica-titania mixture was small or when the ratio of silica to titania in the mixture was high.

• Journal of the Korean Chemical Society
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• v.20 no.4
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• pp.251-259
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• 1976

Graft site distribution of graft polymer was derived from a statistical model. Theoretical model was experimentally confirmed by preparing well defined graft polymer and using gel permeation chromatography(GPC). The results indicate that metalation of substrate polymer is statistically random process and anionic graft reaction products consist of ungrafted free side chain homopolymer; graft polymer with different number of graft chains and free backbone molecules when the averaged in the graft sites are small.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1451-1456
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• 2012

A novel tetrathiafulvalene (TTF)-based main-chain polymer (6TTF-polymer) was successfully synthesized via a condensation polymerization between a newly synthesized dihydroxy TTF derivative and a malonyl chloride, and its chemical structure was characterized by spectroscopic techniques. Molecular weight of the 6TTF-polymer (9,030 g/mol by gel permeation chromatography) was large enough to form the ductile film. The electrochemical and optical properties of the 6TTF-polymer were further estimated by cyclic voltammetry, ultraviolet and photoluminescence spectroscopes. The highest occupied molecular orbital level ($E_{HOMO}$=-4.79 eV) and band-gap energy ($E_g$=1.91 eV) of the 6TTF-polymer suggested that TTF-based polymer could act as a good electron donating material for the optoelectronic applications.

• Radiation Oncology Journal
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• v.20 no.3
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• pp.264-273
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• 2002

Purpose : Three-dimensional radiation dosimetry using magnetic resonance imaging of polymer gel was recently introduced. This dosimetry system is based on radiation induced chain polymerization of acrylic monomers in a muscle equivalent gel and provide accurate 3 dimensional dose distribution. We planned this study to evaluate the clinical value of this 3-dimensional dosimetry. Materials and Methods: The polymer gel poured into a cylindrical glass flask and a spherical glass flask. The cylindrical test tubes were for dose response evaluation and the spherical flasks, which is comparable to the human head, were for isodose curves. T2 maps from MR images were calculated using software, IDL. Dose distributions have been displayed for dosimetry. The same spherical flask of gel and the same irradiation technique was used for film and TLD dosimetry and compared with each other. Results : The R2 of the gel respond linearly with radiation doses in the range of 2 to 15 Gy. The repeated dosimetry of spherical gel showed the same isodose curves. These isodose curves were identical to dose distributions from treatment planning system especially high dose range. In addition, the gel dosimetry system showed comparable or superior results with the film and TLD dosimetry. Conclusion : The 3-dimensional dosimetry for conformal radiation therapy using MRI of polymer gal showed stable and accurate results. Although more studies are needed for convenient clinical application, it appears to be a useful tool for conformal radiation therapy.