• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2357-2360
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• 2014

Phosphorus-doped soft carbons were successfully prepared by carbonizing petroleum cokes treated with phosphorus acids, such as $H_3PO_2$, $H_3PO_3$, and $H_3PO_4$. The effect of the type of phosphorus acids used on the composition, structure, and electrochemical performance of the soft carbons was extensively investigated. The soft carbons modified with $H_3PO_3$ and $H_3PO_4$ exhibited dramatically improved reversible capacities and outstanding rate capabilities.

• Carbon letters
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• v.15 no.4
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• pp.277-281
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• 2014

A series of high capacity soft carbons with different phosphorus contents were successfully prepared by carbonizing petroleum cokes treated with hypophosphorous acid at $900^{\circ}C$. The effect of phosphorus content on the electrochemical performance of the soft carbons was extensively investigated. The P-doped soft carbons exhibited greatly enhanced discharge capacities and outstanding rate capabilities with increasing phosphorus content. In addition, the influence of temperature on the electrochemical behaviors of the soft carbons was investigated in a wide temperature range of $25^{\circ}C$ to $50^{\circ}C$. Surprisingly, the electrochemical properties of the pristine and P-doped soft carbons were highly sensitive to the operating temperature, unlike conventional graphite. The pristine and P-doped soft carbons exhibited significantly high discharge capacities of 470 and 522 mAh/g, respectively, at a high temperature of $50^{\circ}C$.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.144.2-144.2
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• 2013

With the synthesis of graphene sheets as large-scale and high quality, it is essentially important to develop suitable graphene patterning process for future industrial applications. Especially, transfer or patterning method of CVD-grown graphene has been studied. We report simple soft lithographic process to develop easily applicable patterning method of large-scale graphene sheets by using chemically functionalized polymer stamp. Also important applications, the prototype capacitors with graphene electrode and commercial polymer dielectrics for the electrostatic-type touch panel are fabricated using the developed soft lithographic patterning and transfer process.

• Natural Product Sciences
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• v.1 no.1
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• pp.70-85
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• 1995

The chemical constituents of the soft corals of Lobophytum are reviewed.

• Bulletin of the Korean Chemical Society
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• v.23 no.4
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• pp.613-616
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• 2002

• Polymer(Korea)
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• v.31 no.6
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• pp.543-549
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• 2007

We synthesized various polyurethanes(PU) haying different hard segments with different molecular weights of the soft segment to explore the effect of structure on the dispersion of silver particle in the phase of synthesized polyurethanes matrix. The thermal stability was increased by increasing the number of aromatic compound, while the degree of dispersion for silver particle was decreased. Silver particles showed better dispersion in the PU matrix having aromatic compounds when the soft segments were held constant. On the contrary, when the hard segment was held constant, silver particles on the PU matrix haying low $M_w$ of soft segment showed better dispersion than high $M_w$ of soft segment because poor chain mobility of low $M_w$ of soft segment restricted re-aggregation of silver particle. A sheet resistance of composite materials showed different aspects. In this case, the inter connection between silver particles was more important than its dispersion. In this study, the NDI-PEG 900/silver particle composite film showed the best thermal stability and electro conductivity.

• Journal of Sensor Science and Technology
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• v.33 no.1
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• pp.7-11
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• 2024

Soft-pressure sensors have numerous applications in soft robotics, biomedical devices, and wearable smart devices. Herein, we present a highly sensitive electronic skin device with an isotropic wrinkled pressure sensor. A conductive ink for soft pressure sensors is produced by a solution process using polydimethylsiloxane (PDMS), poly 3-hexylthiophene (P3HT), carbon black, and chloroform as the solvents. P3HT provides high reproducibility and conductivity by improving the ink dispersibility. The conductivity of the ink is optimized by adjusting the composition of the carbon black and PDMS. Soft lithography is used to fabricate a conductive elastic structure with an isotropic wrinkled structure. Two conductive elastic structures with an isotropic wrinkle structure is stacked to develop a pressure sensor, and it is confirmed that the isotropic wrinkle structure is more sensitive to pressure than when two elastic structures with an anisotropic wrinkle structure are overlapped. Specifically, the pressure sensor fabricated with an isotropic wrinkled structure can detect extremely low pressures (1.25 Pa). Additionally, the sensor has a high sensitivity of 15.547 kpa^-1 from 1.25 to 2500 Pa and a linear sensitivity of 5.15 kPa^-1 from 2500 Pa to 25 kPa.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.176.2-176.2
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• 2014

In this work, we demonstrated that the fabrication of flexible graphene-based chemical sensor with heaters by soft lithographic patterning method [1]. First, monolayer and multilayer graphene were prepared by thermal chemical vapor deposition transferred onto SiO2 / Si substrate in order to fabrication of patterned-sensor and -heater. Second, patterned-monolayer and multilayer graphene were detached through soft lithography process, which was transferred on top and bottom sides of PET film. Third, Au / Ti (Thickness : 100/30 nm) electrodes were deposited end of the patterned-graphene line by sputtering system. Finally, we measured sensor properties through injection of NO2 and CO2 gas on different temperature with voltage change of graphene heater.

• Macromolecular Research
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• v.10 no.4
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• pp.230-235
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• 2002

Alternating polyols of oxymethylene and oxyalkylene were synthesized and used as precursors for thermoplastic poly(ether-ester) elastomers (TPEs). The polyols were synthesized by reacting diols having different methylene units with dichloromethane in the presence of a phase transfer catalyst. The number of methylene units in the alkylene oxides was varied from 3 to 6. TPEs were prepared using the polyols as soft segments and poly(butylene terephthalate) units as hard segments. The polyols and TPEs synthesized were characterized using FTIR, NMR, GPC, DSC, and polarized optical microscopy. The polyols showed a profound odd-even effect on the melting (T$_{m}$) and glass transition temperatures (T$_{g}$). Polyols with odd numbers of methylene groups in the alkylene units have higher transition temperatures than polyols with odd number of methylene groups. The tendency is still kept in TPEs, even though the T$_{g}$ of soft segment in TPEs are slightly higher than those of corresponding neat polyols. The T$_{m}$ and T$_{g}$ of soft segments are almost constant in the range of 20 to 60 wt % contents of soft segments. On the other hand, the normalized heat of fusion of hard segment decreased with increasing the content of loft segment.ent.t.ent.

• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1361-1364
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• 2003