• Macromolecular Research
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• v.14 no.2
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• pp.187-193
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• 2006

Organoclay, was applied as a filler, in place of carbon black and silica, to a natural rubber (NR)/butadiene rubber (BR) blend. A compounding method was used to disperse and separate the layered silicates. The effect of a coupling agent on the vulcanizates was evaluated using both the silica and organoclay filled compounds. After the compounding processes were completed, the XRD diffraction peaks disappeared, but then reappeared after vulcanization. The scorch times for the organoclay-filled compounds were very short compared to those for carbon black and silica-filled compounds. The organoclay-filled compounds showed high values of tensile strength, modulus, tear energy, and elongation at the break. When ranked by viscosity, the compounds appeared in the following order: silica > silica (Si-69) > organoclay > organoclay (Si-69) > carbon black. Fractional hysteresis, tensile set, and wear rates were very consistent with the viscosity of the vulcanizates. The Si 69 coupling agent increased reversion resistance, the maximum torque values in the ODR, modulus, and wear resistance, but decreased elongation at the break, fractional hysteresis, and tension set of the vulcanizates.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.3
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• pp.74-82
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• 2004

The botanical antimicrobial agent prepared from citrus fruits (BAAC) was prepared to provide inhibitory ability to packaging paper The BAAC diluted in 0.5% and 1% starch solution respectively was applied to packaging paper by the thin coating technique. The antimicrobial packaging paper displayed great inhibitory effect against the putrefying microbes including fungi, yeast and bacteria. Tn addition to antimicrobial activity of the packaging papers, their physical properties such as tensile strength, burst strength, tear strength and bending stiffness could be improved by simultaneous treatment with starch. Both the item packaging by tissue paper and the outer packaging by corrugated boxes, which were treated by the thin coating of BAAC and starch, exhibited great ability in preserving freshness of stored mandann oranges. The more treatment of BAAC was made in the packaging paper, the greater freshness-preserving ability was generated.

• Journal of the Korean Applied Science and Technology
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• v.12 no.2
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• pp.51-58
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• 1995

To prepare a durable softening water repellent, quaternized octadecyl methacrylate-2-diethyl-aminoethyl methacrylate as a mother resin and quaternized 1, 3-dioctadecyl-2, 7-dioxy-6, 8-di(2-hydroxyethyl)-1, 3, 6, 8-tetraazacyclodecane which increase the softening effect and the hydrostatic pressure blended with waxes and their emulsifier in various proportions to give water repellent PADWC. As the results of the measurement of water repellency, washable, tear strength and crease recovery to polyestercotton(P/C) blended fabrics treated with PADWC only or addition of textile finishing resin, the physical properties were increased. There was no significant lowering effect in water repellency when PADWC was treated the antistatic agent by the one-bath method, and the effect of water repellency by the adding the catalyst was studied. PADWC was confirmed as durable water repellent with the results of making little difference of water repellency as ${\pm}5$ point after and before washing.

• Journal of Korean Orthopaedic Sports Medicine
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• v.12 no.1
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• pp.8-15
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• 2013

Although total meniscectomy had been performed as a treatment of meniscal tear, many published articles reported progression of the degeneration process in the articular cartilage and development of the osteoarthritis after meniscectomy. With the increased knowledge of the biomechanical properties of the meniscus, meniscal repair has been performed increasingly to maintain the important functions of the meniscus. Outside-in, inside-out, all-inside technique have been used as meniscal repair methods. In this review, indications, operative technique, and outcomes of the all-inside meniscal repair are discussed.

• Elastomers and Composites
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• v.38 no.2
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• pp.122-127
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• 2003

Compounding, using such thermoplastic elastomer as styrene-ethylene-butadiene-styrene (SEBS) blended with polypropylene(PP), oil, and other ingredients, was studied to develop a new material with excellent impact resistance and resilience for the replacement of environmentally toxic PVC sheet. Hardness decreased linearly with oil content in the SEBS/oil blend, and the tensile strength increased with PP content whereas elongation showed no effects over 50 phr of PP in SEBS/oil/PP blend. In the practical SEBS composition, proposed to replace the PVC sheet material, tensile and tear strength, as well as hardness, increased proportionally with PP content, while melt index decreased.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.173-179
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• 2018

Electrochemical characterization was conducted on poly(vinyl alcohol) (PVA)-ceramic composite (PVA-CC) separators for supercapacitor applications. The PVA-CC separators were fabricated by mixing various ceramic particles including aluminum oxide ($Al_2O_3$), silicon dioxide ($SiO_2$), and titanium dioxide ($TiO_2$) into a PVA aqueous solution. These ceramic particles help to create amorphous regions in the crystalline structure of the polymer matrix to increase the ionic conductivity of PVA. Supercapacitors were assembled using PVA-CC separators with symmetric activated carbon electrodes and electrochemical characterization showed enhanced specific capacitance, rate capability, cycle life, and ionic conductivity. Supercapacitors using the $PVA-TiO_2$ composite separator showed particularly good electrochemical performance with a 14.4% specific capacitance increase over supercapacitors using the bare PVA separator after 1000 cycles. With regards to safety, PVA becomes plasticized when immersed in 6 M KOH aqueous solution, thus there was no appreciable loss in tear resistance when the ceramic particles were added to PVA. Thus, the enhanced electrochemical properties can be attained without reduction in safety making the addition of ceramic nanoparticles to PVA separators a cost-effective strategy for increasing the ionic conductivity of separator materials for supercapacitor applications.

• Textile Coloration and Finishing
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• v.30 no.4
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• pp.321-328
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• 2018

Wet polyurethane resin was synthesized by using polytrimethylene ether glycol prepared from 1,3-propanediol produced by fermentation from corn sugar as bio polyol and polyether-polyol(PTMG). Physical properties and cell characteristics by wet coagulation were investigated using the synthesized wet polyurethane resin. The tensile strength of wet polyurethane resin decreased with increasing content of bio polyol as copolymer polyol, but it tended to increase elongation at break and tear strength. As a result of thermal characteristic analysis, it was found that the glass transition temperature was slightly increased as the content of bio polyol increased. As a result of comparing the cell characteristics by the wet coagulation method, it was found that the shape of the cell was good when the ether polyol and the bio polyol were used alone.

• Textile Coloration and Finishing
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• v.34 no.3
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• pp.173-184
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• 2022

In this study, the TPU film was laminated on an aramid fabric or circular knits in order to implement an air cushion material that can respond to high impact forces in case of a fall and is easy to expand. To increase the bonding strength between the fabric layer and the film layer, a primer layer was formed in two ways: one for thermally bonding and laminating PET film and two for coating and aging hot melt type PUR adhesive. The tensile strength of the aramid air cushion was 2.5 times higher than that of the circular knits, but the tensile elongation of the aramid air cushion was very low compared to that of the circular knits. The tear strength of the aramid air cushion was about twice or more superior to that of the circular knits, the primer treatment method was good at A, and the peel strength was excellent at method A. The aramid air cushion was the lightest in weight. Summarizing the above results, it was best to combine the air cushion material with aramid woven fabric and primer treatment method A to cope with the high impact force applied when falling.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.269-279
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• 2021

In this study, the laminating of TPU film after coating of primer adhesive on the fabrics was applied in order to secure the strength to withstand a fall from a higher altitude by increasing the adhesion between the fabric and the film layer. It seems that the fineness of the yarn and the weave construction have a greater effect than the type of the laminating films. The order of superiority of the laminated fabrics by film type and thickness was the same for 1000 denier and 210 denier fabrics, and the tendency was consistent with the order of superiority in the film properties and peel strength tests. The tear strength of laminating fabrics increased three to four times for 1000 denier fabrics compared to the fabric alone, but it decreased by 2 times for the 210 denier fabrics. Summarizing the above results, it is most appropriate to combine 1000d fabric with three types of laminating films(100~200㎛ thickness) of A(0.2T) or B(0.15T) or D(0.1T) considering the air pressure resistance, the impact resistance during the fall, and the durability against damage during use.

• Journal of the Korean Applied Science and Technology
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• v.8 no.1
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• pp.9-20
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• 1991

In the preparation of acrylic water repellent(EDLWC). quaternized 2-diethylarrunoethylmethacrylate-stearylmethacrylate copolymer (DSACC) and quaternized 1-Iaurovlbis(aminoethyl)-2-dodecylimidazoline(LDDIC) were selected as a basic resin and the improving agent such as softening effect and hydrostatic pressure of the water repellent. EDLWC was prepared by blending waxes and emulsifier for waxes with various ratio to DSACC and LDDIC. As the results of the measurement of water repellency, washable, tear strength and crease recovery to polyester-cotton(P/C) blended fabrics treated with EDLWC only or addition of textile finishing resin, the physical properties were increased. Sodium acetate was the most effective catalyst in the water repellency among the various kinds of catalyst. and the reasonable concentration of the catalyst was 1. 4 wt%. EDLWC was confirmed as durable water repellent with the results of making little difference of water repellency as ${\pm}5$ point after and before washing. The reaction mechanism between P/C blended fabrics and EDLWC in the presence of catalyst was proposed. And also, the longitudinal view of the P/C blended fabrics treated with water repellent was observed with scanning electron microscope.