• Elastomers and Composites
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• v.50 no.3
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• pp.159-166
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• 2015

Silica which is used for reinforcing filler in tire industry is widely known as eco-friendly material exerting $CO_2$ reduction effect through decrease of rolling resistance and improvement of wet grip. Generally silica is classified as a highly polar filler because it contains a large number of silanol (Si-OH) group on its surface. And also silica gives a lower reinforcing effect than carbon black due to its poorer rubber-filler interaction. Therefore silica is treated with silane coupling agent or activator, then following the conventional rubber blend method, vulcanized sheets were prepared using a hot press, and cure characteristics, mechanical properties and abrasion resistance of the test specimens were investigated. It was found that with an increase in the silane coupling agent content the tensile strength, 300% modulus and abrasion resistance increased while Mooney viscosity decreased and crosslink density slightly increased with an increase of activator.

• Journal of Powder Materials
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• v.1 no.2
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• pp.135-144
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• 1994

Silicon carbide powder was prepared from mixtures of Sangdong silica sand and carbon black by SHS (Self propagating High temperature Synthesis) method which utilizes magnesiothermic reduction of silica. In the powder preparation process, the reacted powder was leached by chloric acid to remove the magnesium oxide and was subsequently roasted to remove free carbon. The impurities were mostly eliminated by hot acid treatment. The resultant SiC powder showed the mean particle size of 0.22 ${\mu}{\textrm}{m}$ and the specific surface area of $66.55 m^2/g$. The SiC powder was mixed with 1 wt% of boron and of carbon to increase densification rate. The mixed powder was pressed and sintered pressurelessly at $2100^{\circ}C$ for 30 min in argon gas. The sintered body showed the hardness of $2550 kg{\cdot}f/mm^2$ and the fracture toughness, KIC of $3.47 MN/m^{3/2}$.

• Macromolecular Research
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• v.17 no.9
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• pp.718-720
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• 2009

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.1
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• pp.5-14
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• 2023

In this study, LiDAR-reflective black hollow-structured silica/titania(B-HST) materials are successfully synthesized by employing the NaBH₄ reduction and etching method on silica/titania core/shell(STCS) materials, which also effectively enhance near-infrared(NIR) reflectance. Moreover, core-etched supernatant solutions are collected and recycled for the synthesis of extracted silica(e-SiO₂) process, which successfully applies as filler materials for semiconductor epoxy molding compound(EMC). In detail, B-HST materials, fabricated by the sequential experimental steps of sol-gel, reduction, and sonication-mediated etching method, manifest blackness(L^*) of 13.2 similar to black paint and excellent NIR reflectance(31.1%). Consequently, B-HST materials are successfully prepared as LiDAR-reflective black materials. Additionally, core-etched supernatant solution with silanol precursors are employed for synthesis of homogeneous silica filler materials via sol-gel method. As-synthesized silica fillers are incorporated with epoxy resin and carbon black for the preparation of semiconductor EMC. Experimentally synthesized EMC exhibits comparable mechanical-chemical properties to commercial EMC. Conclusively, this study successfully proposes designing procedure and practical experimental method for simultaneously synthesizing the NIR-reflective black materials for self-driving vehicles and EMC materials for semiconductors, which are materials suitable for the industrial 4.0 era, and presented their applicability in future industries.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.608-613
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• 1998

The purpose of this experiment was the physical properties of rubber compounds with DPCB and pure carbon black. Si-O peak in the silcia surface was observed at the range of wavenumber from 1,100 to 1,200 in the DPCB by FT-IR analysis. Cure rate of rubber compounds containing DPCB and organic silane coupling agent were (Si69) delayed compared with those containing pure carbon black. 300% modulus and interaction coefficient of DPCB with silane coupling agent were higher than those of pure carbon black and PICO weight loss amount showed constant value. It was found that $0^{\circ}C$ tan$\delta$ of rubber compounds with DPCB was larger than those of pure carbon black at 2.0% silane coupling agent based on 50 phr DPCB and $60^{\circ}C$ tan$\delta$ of rubber compounds with DPCB decreased as increasing the usage coupling agent. Consequently, it is postulated that DPCB is strong candidate material for lowering rolling resistance under constant abrasion resistance.

• KIEAE Journal
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• v.17 no.3
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• pp.107-112
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• 2017

Purpose: Both silica gel and activated carbon black particles were adopted for use as PCM absorbed porous media applicable as construction materials. To investigate usable methods for absorbing PCM into the media, they were soaked into PCM and also tested for enhancement of PCM absorption into them. Method: To test PCM absorption into some porous media such as both ${\varphi}1{\sim}2mm$ and $10{\mu}m$ silica gels, and $50{\mu}m$ activated carbon black, $43^{\circ}C$ PCM was used as a laten heat material. The method, soaking into PCM was applied to this study, and the media were moderately rotated by centrifuge to have the extra PCM flow out. DSC analysis was conducted to investigate the melting and solidifying of the PCM absorbed into the porous media. Result: It was found that PCM was absorbed into the porous media by over 85 wt% of all particles. In addition, it was noted that the ultrasonic vibrator was accelerating the PCM absorption into the particles to three times higher speed than simple soaking. Centrifuge was adopted to remove extra PCM sticking on the particle surfaces and extra PCM was moderately removed from the surfaces of the particles. DSC analysis indicated that the latent heat of the absorbed PCM particles was 160 J/g, and the melting temperature was approximately $40^{\circ}C{\sim}50^{\circ}C$.

• Elastomers and Composites
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• v.48 no.3
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• pp.181-189
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• 2013

Unfilled, carbon black-filled, and silica-filled natural rubber (NR) composites were aged with a circular deformation at $60-90^{\circ}C$ and the recovery behaviors were investigated. The samples were aged under the altering aging medium systems of air and distilled water every day for 10 days. The order of the recoveries according to the filler systems was unfilled > silica > carbon black. The recoveries of the samples aged in the air to water altering system were greater than those of the samples aged in the water to air altering system. The initial aging medium dominantly influenced the deformation level.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.73-75
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• 2012

In this study, basic physical properties and color development of the black concrete depending on CASB-SP dosages are investigated. According to results, It showed that the slump and air contents of the concrete containing CASB-SP meet all requirements of concrete except when CASB-SP 5.0 % is used. It also showed that the more the CASB-SP is used, the higher the compressive strength becomes. On the other hand, It is found that if the CASB-SP 5.0 % is used, the compressive strength was reduced as the more CASB-SP 5 % is used. In terms of color, it was found out that the more CASB-SP is used, the darker the black becomes.

• Elastomers and Composites
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• v.48 no.2
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• pp.125-132
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• 2013

In this work, we have discussed new engineering systems for preparing carbon master batch composed by carbon black and various organic compounds. In general, polymer resin, which applied for automobile tire, household items, and various industry items, is used with the fillers including carbon black and silica to control the color or properties. Domestic part and material industry has been remarkably developed in that the development of materials including the compounding of raw materials. Meanwhile, the engineering technique for mass production has not reached to a requirement of industry due to slow technique development and high dependence on foreign. Thus, we will focus on the introduction of new engineering technique developed by domestic company for preparing carbon master batch.

• Elastomers and Composites
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• v.42 no.4
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• pp.201-208
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• 2007

In this study, the thermal shrinkage and expansion stresses of filled NR and SBR vulcanizates were measured to investigate the dimensional stability at an elevated temperature. When a rubber sample was held at constant pre-strain, a thermal stress developed upon heating due to the entropic consideration. The peak shrinkage stress of carbon black or silica filled NR decreased with increasing filler content. In SBR compounds, however, the peak shrinkage stress of SBR with 30 phr filler content was higher than that of unfilled compounds. The expansion stress of carbon black filled NR was changed little, but that of filled SBR increased with increasing the filler content. The peak expansion stress of silica filled NR and SBR vulcanizates increased with increasing silica content.