• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.173-176
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• 1999

Crosslinked Decree is an important 7actor to determine dielectric property of crosslinked polyethylene(XLPE) used for the insulation material in Power cables. Recently, though it is necessary to investigate electrical properties according to crosslinked degree as a Part of the whose characterization of cable. it is not examined closely. In this study. crosslinked degree of samples were measured according to temperature and holding time of crosslinking. electrical tree characteristics of these characteristics of these samples were analyzed by crosslinked degree and applied temperature that was chanced from normal temperature to operating temperature of power cables. As a result. when the crosslinked degree was low, dielectric properties were decreased and influence of temperature was increased. but the crosslinked degrees were high, initiation voltages of treeing were increased and dielectric properties were improved. It is proved that the optimum crosslinked degree was one of most important factor for aging time and residual lifetime of Power cable.

• Elastomers and Composites
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• v.33 no.3
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• pp.193-200
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• 1998

It is well known that EPDM(ethylene propylene diene monomer) rubber has inherently excellent resistance to the weathering, ozone, heat, cold and moisture, whereas crosslinked IIR (isobutylene isoprene divlnyl benzene terpolymer) shows proper resistance to the water and gas permeation. Various characteristics of EPDM blend with crosslinked IIR such as curing characteristics, mechanical properties, dispersion of minor component and gas impermeability were explored. The optimum curing time $(t_{90})$ examined with peroxide was decreased by adding small amount of crosslinked IIR to the EPDM rubber. Mechanical properties of blends such as tensile strength, hardness and elongation at break were enhanced by increasing EPDM content. These results might be explained with the affinity of carbon black to the EPDM rubber. On the other hand, the physical properties were not changed significantly after aging, and the increase of crosslinked IIR fraction caused the decrease of compression set to small rate. EPDM rubber shows different behavior with crosslinked IIR in oxygen permeability. By adding 30wt.% crosslinked IIR to the EPDM rubber, the resistance to the oxygen permeation was improved up to three times than that of pure EPDM rubber. Conclusively, EPDM blend containing 30wt.% crosslinked IIR might be commercially applied to the o-ring and electric parts because of its proper resistance to the weathering, ozone and oxygen permeability.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1468-1472
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• 2007

The present study was carried out to determine the optimum conditions of different factors (ratio of lard to water, ${\beta}$-CD concentrations, mixing temperature, mixing time and mixing speed) on cholesterol reduction from lard by using crosslinked ${\beta}$-CD. Crosslinked ${\beta}$-CD was prepared with adipic acid. When the lard was treated under different conditions, the range of cholesterol removal was 91.2 to 93.0% with 5% crosslinked ${\beta}$-CD, which was not significantly different among treatments. In a recycling study, cholesterol removal with crosslinked ${\beta}$-CD in the first trial was 92.1%, which was similar to that with new crosslinked ${\beta}$-CD. In up to eight time trials, over 90% of cholesterol removal was found. The present study indicated that the optimum conditions for cholesterol removal using crosslinked ${\beta}$-CD were a 1:3 ratio of lard to water, 5% crosslinked ${\beta}$-CD concentration, $40^{\circ}C$ mixing temperature, 1 h mixing time and 150 rpm mixing speed. In addition, crosslinked ${\beta}$-CD made by adipic acid resulted in an effective recycling efficiency.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.901-903
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• 1998

Crosslinked Degree is an important factor to determine dielectric property of crosslinked polyethylene(XLPE) used for the insulation material in power cables. Recently, though it is necessary to investigate electrical properties according to crosslinked degree as a part of the whole characterization of cable. it is not examined closely. In this study, crosslinked degree of samples were measured according to temperature and holding time of crosslinking, electrical tree characteristics of these samples were analyzed by crosslinked degree and applied temperature that was changed from normal temperature to operating temperature of power cables. As a result. when the crosslinked degree was low, dielectric properties were decreased and influence of temperature was increased. but the crosslinked degrees were high. initiation voltages of treeing were increased and dielectric properties were improved. It is proved that the optimum. crosslinked degree was one of most important factor for aging time and residual lifetime of power cable.

• Journal of the Korean Electrochemical Society
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• v.12 no.3
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• pp.245-250
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• 2009

Crosslinked membrane based on sulfonated polyimide was prepared by the introduction of crosslinkable monomer in polymerization process and crosslinking during membrane casting. Crosslinked membranes showed different properties from non-crosslinked membranes. Crosslinking decreased methanol crossover and therefore unit cell using crosslinked membrane showed increased open circuit voltage, 0.81 V, in comparison with unit cell using noncrosslinked membrane, 0.71 V. In addition, water uptake of crosslinked membrane, 40.5%, was lower than that of non-crosslinked membrane, 57.0%, and this resulted in improved dimensional stability. However, proton conductivity of crosslinked membranes showed rather low relative to non-crosslinked membrane due to reduced water uptake.

• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.140-145
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• 2001

In order to apply for silane crosslinking process to PTC products, especially. self-regulating heater, silane crosslinked samples were compared with radiation crosslinked sample in terms of PTC characteristic and PTC stability. Silane crosslinked samples have lower PTC intensity than radiation crosslinked sample. It can be explained that multiple networks of silane crosslink restrict the movement of molecules in the composite as the sample is heating. As a result of heat cycles at $140^{\circ}C$, the changes of volume resistivity and PTC intensity for radiation crosslinked sample were higher than those of silane crosslinked samples. Whereas, in the case of heat cycles at $85^{\circ}C$, which is limiting temperature for self-regulating heater, both silane and radiation crosslinked samples show stable results without pronounce changes of resistivity up to five cycles.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.793-797
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• 2005

Optimum conditions for cholesterol removal in egg yolk were evaluated based on ratio of egg yolk-to-water, crosslinked ${\beta}$-cyclodextrin (${\beta}$-CD) concentration, and mixing temperature, time, and speed by adding crosslinked ${\beta}$-CD treated with adipic acid. Cholesterol removal in egg yolk-water mixture increased with increasing ${\beta}$-CD level (10-25%). About 95% was removed by 25% ${\beta}$-CD at 1:1 ratio of egg yolk-to-water and 800 rpm mixing at $40^{\circ}C$ for 30 min. In recycling study, removal rates were measured using ten times recycled crosslinked ${\beta}$-CD in egg yolk, and 85% cholesterol removal was observed with eight times reuse. These results indicated that over 90% cholesterol was removed at 1:1 ratio of egg yolk-to-water, 20% crosslinked ${\beta}$-CD addition, and 30 min mixing with 600 rpm at $40^{\circ}C$.

• Journal of Electrochemical Science and Technology
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• v.13 no.3
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• pp.339-346
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• 2022

Silicon (Si) has attracted considerable attention due to its high theoretical capacity compared to conventional graphite anode materials. However, Si-based anode materials suffer from rapid capacity loss due to mechanical failure caused by large volume change during cycling. To alleviate this phenomenon, crosslinked polymeric binders with strong interactions are highly desirable to ensure the electrode integrity. In this study, thermally crosslinked polyimide binders were used for Si-alloy anodes in Li-ion batteries. The crosslinked polyimide binder was found to have high adhesion strength, resulting in enhanced electrode integrity during cycling. Therefore, the Si-alloy anodes with crosslinked polyimide binder provide enhanced electrochemical performance, such as Coulombic efficiency, capacity retention, and cycle stability.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1794-1799
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• 2005

The present study was carried out to develop crosslinking of $\beta$-cyclodextrin ($\beta$-CD) using adipic acid, and to determine the optimum conditions of different factors ($\beta$-CD concentration, mixing temperature, mixing time and mixing speed) on cholesterol reduction from homogenized milk. Crosslinked $\beta$-CD was prepared with adipic acid. When the milk was treated with different conditions, the cholesterol removal rate was in the range of 92.1 to 93.1% with 1% $\beta$-CD addition, which were not significantly different among treatments. After cholesterol removal from milk, the used crosslinked $\beta$-CD was washed for cholesterol dissociation and reused. For recycling study, the cholesterol removal rate in the first trial was 92.5%, which was mostly same as that using new crosslinked $\beta$-CD. With repeated ten time trials using same sample, 81.4% of cholesterol was removed from milk. Therefore, the present study indicated that the optimum conditions for cholesterol removal using crosslinked $\beta$-CD were 1% $\beta$-CD addition and 10 min mixing with 400 rpm speed at 5$^{\circ}C$ with over 90% cholesterol removal. In addition, crosslinked $\beta$-CD made by adipic acid resulted in the effective recycling efficiency.

• Journal of Dairy Science and Biotechnology
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• v.25 no.1
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• pp.9-13
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• 2007

The present study was carried out to examine the effect of crosslinked ${\beta}$-cyclodextrin(${\beta}$-CD) made by adipic acid on cholesterol removal rate and find the structural change after recycling on SEM observation. The size reduction and morphological changes were found during the recycling process and the profound changes were observed at 8th time reuse. After cholesterol removal in milk, the used crosslinked ${\beta}$-CD was washed for cholesterol dissociation and reused. In recycling study, the cholesterol removal rate at first trial was 92.5% in milk, which was mostly same as that using new crosslinked ${\beta}$-CD(92.4%). With repeated 10th reuse of crosslinked ${\beta}$-CD resulted in 81.4% of cholesterol removal in milk. Similar trend was found in cream and cholesterol removal was 91.5% at 1st trial and 83.4% at 10th trial. In both milk and cream samples, the removal rate at 1st reuse was not significantly different from that at 6th reuse(p>0.05). The present study indicated that crosslinked ${\beta}$-CD made by adipic acid resulted in the effective recycling efficiency, especially up to 6th reuse and morphological modifications were not distinguishable up to 8th reuse.