• 접착 및 계면
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• 제16권3호
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• pp.108-115
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• 2015

본 연구는 poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/그래핀 복합체의 제조 및 특성에 관한 연구이다. 투입하는 그래핀의 함량에 따른 복합체의 전기적 물성, 소수성, 및 열적 성질에 미치는 영향에 대해 연구하였다. 표면주사전자현미경 연구결과 PHBV 고분자 matrix에 판상의 그래핀이 고르게 잘 분산되었음을 확인하였다. X-선 회절 연구와 시차열량주사계 분석을 통하여 그래핀을 첨가할수록 PHBV의 결정도를 증가시켰고, 투입하는 그래핀의 함량이 증가할수록 복합체의 열적 안정성, 소수성 및 전기전도도 등이 증가하는 것으로 나타났다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.185-190
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• 2005

Safe, economical and environment-friendly tunnel construction are required again along with social continuous development, the importance of waterproof work that is portion that actually all of user and builder can find that is embossed by tunnel construction's one of important construction. Also, ECB (Ethylen Copolymer Bitumen) sheet that is used in existing tunnel waterproofing method (ECB waterproofing method) being black because asphalt (Bitumen) is added, by purpose that make illumination of tunnel interior brightly and scar discovery eases in sheet with coating white film, but ECB that is used present according as ECB that asphalt is added does not satisfy high tensile strength of construction field, quality standard of extension. Also ECB denigrates color of black M/B that asphalt is excepted.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.157-160
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• 2005

The surface energies and acid-base interaction between the untreated and treated Jute or Hemp fibers and different matrix compositions of polypropylene-maleic anhydride polypropylene copolymers (PP-MAPP) were investigated using dynamic contact angle measurement. The contribution of the acid-base property into the interfacial adhesion of the natural fibers/matrix systems were characterized by calculating the work adhesion coming from the acid-base interaction. On the other hand, microfailure mechanism of both single Jute and Hemp fiber bundles were investigated using the combination of single fiber tensile test and acoustic emission. Distinctly different micro failure modes of the different natural fiber/polypropylene systems wet ε observed using optical microscope and determined indirectly by AE and their FFT analysis.

• 한국전기전자재료학회논문지
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• 제19권9호
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• pp.868-872
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• 2006

In this work, the effects of the corona treatment on surface properties of semiconducting silicone rubber were investigated in terms of contact angles, ATR-FTIR(Attenuated total reflection fourier transform infrared spectroscopy) and XPS(X-ray photoelectron spectroscopy). And the adhesive characteristics were studied by measuring the T-peel strengths. Based on chemical analysis, the surface modification can be mainly ascribed to the creation of chemically active functional groups such as C-O, C=O and C-OH on semiconducting silicone surface. This oxidized rubber layer is inorganic silica-like structure of Si bound with three to four oxygen atoms ($SiOx,\;x=3{\sim}4$. The Corona treatment produces an increase in joint strength that is maximum for 10 min treatment. However, due to brittle property of this oxidized layer, the highly oxidized layer from too much extended treatment could be act as a weak point, decreasing the adhesion strength.

• 대한기계학회논문집
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• 제16권12호
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• pp.2340-2348
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• 1992

본 연구에서는 드릴(SKH9종)에 스퍼터링법으로 Ti 중간층을 약 0.2$\mu\textrm{m}$의 두께 로 코팅한후, 그 위에 플라즈마 화학증착법으로 TiN박막을 코팅한 드릴로 드릴링 시험 을 행하여 수명을 평가하였으며, 드릴의 내마멸성 및 드릴링한 구멍 내면의 조도를 코 팅하지 않은 드릴 및 TiN 코팅한 드릴과 비교하므로서 Ti/TiN코팅처리에 의한 공구성 능 및 수명향상 효과를 평가하고자 하였다.

• 접착 및 계면
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• 제14권3호
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• pp.121-127
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• 2013

본 연구에서는 열가소성 폴리우레탄(TPU)과 EPDM, NBR 및 BR을 용융 블렌딩하여 TPU/Rubber 블렌드 필름을 제조하고 이들의 조성이 마찰시 표면 파괴와의 관계를 연구하였다. TPU/EPDM과 TPU/BR 블렌드의 마찰시 표면 파괴 특성이 개선되었으며 특히 BR이 우수하였다. 또한, TPU/BR 블렌드에서 BR의 함량이 10 wt% 이상 투입될 때 표면 파괴 및 마킹 특성이 개선되었다. Scanning electron microscopy (SEM) 분석으로부터 BR 함량이 증가할수록 연질상의 증가로 인한 표면 파괴 및 마킹 특성의 개선으로 추정할 수 있었다.

• 풍력에너지저널
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• 제15권1호
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• pp.82-90
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• 2024

Bio-fouling has positive aspects that are used as a fish resource, but there are also negative aspects such as corrosion of the surface of the support structure, aesthetics and work safety problems. A specimen was produced using a polyurea material with excellent anti-fouling and methodology, and contact angle, high water pressure, adhesion, and real sea area tests were performed. As a result of measuring the contact angle of the specimen with a 10 cm x 10 cm area of polyurea, There was found to be an average of 124.4 ° at nine points. No surface damage was found even above 5 Mpa when high water pressure was sprayed, and adhesive strength of 300LSE adhesives was confirmed between 22.84 and 23.04 Mpa with an adhesion test. During the 6-month real sea area test, it was confirmed that about 17.24 % of the polyurea film was less generated than the comparison group.

• Elastomers and Composites
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• 제50권4호
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• pp.265-273
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• 2015

In this work, the emulsified asphalt with high phase stability and storage stability was prepared by using phase inversion emulsification and the surfactant mixed with cationic and nonionic surfactants. It was found that the asphalt together with Span 20, nonionic surfactant and DDA (Dimethyl Dodecyl Amine), cationic surfactant showed the most stable phase. The phase stability of the emulsified asphalt, therefore, was investigated through the particle size with mixed surfactant content, rheology behavior and Zeta potential value; the particle size decreased with the increase of the mixed surfactant content but the viscosity increased. The shear thinning behaviors and the Zeta potential value with 50 mV~60 mV were shown, which was found to be considered stable. In addition, SBR latex(Styrene-butadiene-rubber) and water dispersed Epoxy (EPD) were used to enhance the physical properties of the emulsified asphalt. The swelling and adhesion features of the emulsified asphalt were also studied with $CaCO_3$, Silica, and Montmorillonite (MMT). It was shown that the addition of SBR latex and MMT can be another way to improve the physical properties of the emulsified asphalt in that the lowest swelling feature was found.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.153-156
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• 2005

Nondestructive sensing of electrospun PYDF web and multi-wall carbon nanotube (MWCNT)/epoxy composites were investigated using electro-micromechanical technique. Electrospinning is a technique used to produce micron to submicron diameter polymeric fibers. Electrospun PVDF web was also evaluated for the sensing properties by micromechanical test and by measurement electrical resistance. CNT composite was especially prepared for high volume contents, 50 vol% of reinforcement. Electrical contact resistivity on humidity sensing was a good indicator for monitoring as for multifunctional applications. Work of adhesion using contact angle measurement was studied to correlate acid-base surface energy between carbon fiber and CNF composites, and will study furher for interfacial adhesion force by micromechanical test.

• Tribology and Lubricants
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• 제35권2호
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• pp.106-113
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• 2019

We investigated the application of tetrahedral amorphous carbon (ta-C) coatings to fabricate a glass lens manufactured using a glass molding process (GMP). In this work, ta-C coatings with different thickness (50, 100, 150 and 200 nm) were deposited on a tungsten carbide (WC-Co) mold using the X-bend filter of a filtered cathode vacuum arc. The effects of thickness on mechanical and tribological properties of the coating were studied. These ta-C coatings were characterized by atomic force microscopy, scanning electron microscopy, nano-indentation measurements, Raman spectrometry, Rockwell-C tests, scratch tests and ball on disc tribometer tests. The nano-indentation measurements showed that hardness increased with an increase in coating thickness. In addition, the G-peak position in the Raman spectra analysis was right shifted from 1520 to $1586cm^{-1}$, indicating that the $sp^3$ content increased with increasing thickness of ta-C coatings. The scratch test showed that, compared to other coatings, the 100-nm-thick ta-C coating displayed excellent adhesion strength without delamination. The friction test was carried out in a nitrogen environment using a ball-on-disk tribometer. The 100-nm-thick ta-C coating showed a low friction coefficient of 0.078. When this coating was applied to a GMP, the life time, i.e., shot counts, dramatically increased up to 2,500 counts, in comparison with Ir-Re coating.