• Journal of Adhesion and Interface
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• v.10 no.4
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• pp.169-173
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• 2009

In this study, We were studied on the properties of polyurethane elastomer containing the polyol, chain extender and isocyanate in polyurethane elastomer. Polyurethane elastomer had the best properties with poly(tetramethylene) glycol for in-line skate wheel. With more incorporation of chain extender content in polyurethane elastomer, tensile strength and hardness increased and elongation decreased. And then properties of polyurethane elastomer with the bulky type isocyanate had better than the flexible type isocyanate.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.448-451
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• 2001

각각 소수성과 친수성을 나타내는 올레핀계 고분자인 PE 와 granule starch의 blend는 서로 다른 특성에 기인하여 거시적인 상분리 현상이 발현되며 두 물질간에 계면을 형성한다. 이와 같이 낮은 interfacial adhesion을 갖는 내부 구조는 외력에 대한 저항력이 급격히 저하되어 낮은 물성 특성을 나타낸다. (중략)

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.454-459
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• 2017

In this study, aqueous acrylic emulsion adhesives were prepared using various surfactants and their properties were also investigated. Solids content, conversion, particle size distribution and initial adhesion properties of the prepared adhesives were compared with each other. The solid content of the adhesives was evaluated 60% and the conversion rate of the emulsion polymerization was 97% at 2 wt% concentration of synthesized surfactants. The particle size distribution analysis revealed that the size distribution of adhesive particles was 290~470 nm when the synthesized cationic surfactant was added. The initial adhesion and adhesion time were also improved. The maximum adhesive strength was found to be 2.55 kgf when using a single surfactant (POE 23), and superior to that of using other surfactants. It was confirmed that the corrosion inhibition of the adhesive prepared by adding the cationic gemini surfactant was maintained for 48 hours.

• Polymer(Korea)
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• v.25 no.4
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• pp.587-593
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• 2001

In this work, red mud (RM) was chemically modified by 0.1, 1, and 5 M H3PO4 solution to prepare epoxy/RM nanocomposites. The effect of chemical treatment on pH, acid-base values, specific surface area, and porosity of RM surface was analyzed. To estimate the mechanical interfacial properties of epoxy/RM nanocomposites, the critical stress intensity factor (K$_{IC}$) was measured. From the experimental results, it was clearly revealed that the porosity, specific surface area, and acid values of RM surface were developed as the increase of the treatment concentration due to the increase of acidic functional group, including hydroxyl group on RM surface. The mechanical interfacial properties of epoxy/treated-RM nanocomposites were higher than those of epoxy/RM as-received due to an improvement of interfacial bonding between basic matrix and RM surface.

• Composites Research
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• v.33 no.6
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• pp.415-420
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• 2020

The interfacial properties in carbon fiber composites, which control the overall mechanical properties of the composites, are very important. Effective interface enhancement work is conducted on the modification of the carbon fiber surface with carbon nanotubes (CNTs). Nonetheless, most surface modifications methods do have their own drawbacks such as high temperatures with a range of 600~1000℃, which should be implemented for CNT growth on carbon fibers that can cause carbon fiber damages affecting deterioration of composites properties. This study includes the use of in-situ interfacial polymerization of polyamide 610/CNT to fabricate the carbon fiber composites. The process is very fast and continuous and can disperse CNTs with random orientation in the interface resulting in enhanced interfacial properties. Scanning electron microscopy was conducted to investigate the CNT dispersion and composites morphology, and the thermal stability of the composites was analyzed via thermogravimetric analysis. In addition, fiber pull-out tests were used to assess interfacial strength between fiber and matrix.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.5
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• pp.418-428
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• 2003

Fiber fracture is one of the dominant failure phenomena affecting the total mechanical Performance of the composites. Fiber fracture locations were measured through the conventional optical microscope and the nondestructive acoustic emission (AE) technique and then were compared together as a function of the epoxy matrix modulus and the fiber surface treatment by the electrodeposition method (ED). Interfacial shear strength (IFSS) was measured using tensile fragmentation test in combination of AE method. ED treatment of the fiber surface enlarged the number of fiber fracture locations in comparison to the untreated case. The number of fiber fracture events measured by the AE method was less than optically obtained one. However, fiber fracture locations determined by AE detection corresponded with those by optical observation with small errors. The source location of fiber breaks by AE analysis could be a nondestructive, valuable method to measure interfacial shear strength (IFSS) of matrix in non-, semi- and/or transparent polymer composites.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.04a
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• pp.17-20
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• 1998

1. 서론 : 계면중합은 제조에 따른 박막의 성능 조절이 가능한 이유로 해서 역삼투용 복합막의 주요 제조 방법으로 제시되어 왔다. 계면중합을 응용하여 제조된 복합막의 성능은 반응 단량체의 종류, 용재의 종류, 단량체의 농도, 반응시간, 열처리 유무 및 온도와 시간 등에 의해 변한다. 한편 위의 변수에 절대적인 영향을 받고 아울러 단량체간의 몰 비가 성립하지 않음으로 해서 최적의 막 성능으로 제시되는 조건을 만족하기 위하여 주로 시행착오에 의한 방법을 동원하여 여러 변수에 다른 제조 막의 성능 고찰을 실시하여 왔다. (생략)

• Journal of the Korean Society for Precision Engineering
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• v.24 no.8 s.197
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• pp.15-20
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• 2007

• Composites Research
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• v.30 no.3
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• pp.169-174
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• 2017

Demand of glass fiber reinforced composites (GFRC) increased with developing aircraft and defense industries using resin transfer molding (RTM) process to produce complex product. In this research, wetting, interfacial, and mechanical properties were evaluated with different Cross-linking Density by Molecular Weight of Hardener. Epoxy resin as matrices was used bisphenol-A type and amine-type hardeners with different molecular weight. Specimens were manufactured via RTM and wetting property of resin and glass fiber (GF) mat was evaluated to viscosity of epoxy and injection time of epoxy matrix. Mechanical property of GFRC was determined via flexural strength whereas interfacial properties were determined by interlaminar shear strength (ILSS) and interfacial shear strength (IFSS). The difference in mechanical property depends upon the fiber weight fraction (wt %) of GFRC by RTM as well as the different Molecular Weight of Hardener.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.4
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• pp.343-348
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• 2009

In this study, an efficient sequential bridging method to characterize both the particle size effect and concentration effect on the mechanical properties of nanocomposites at high volume fraction is suggested through a molecular dynamics(MD) simulations and micromechanics of composites materials. The Young's modulus and the shear modulus of the nanocomposites at various particle radius and at 12% volume fraction were obtained from MD simulations and multi-inclusion model was adopted to describe both modulus in continuum model. In order to describe the particle size effect, an additional phase, effective interface, was adopted as characteristic phase and the non-dilute concentration effect which appears at 12% volume fraction was describe via the variation of the elastic modulus of the infinite medium. Both the elastic modulus of the interface and infinite medium were fitted into functions of particle radius for the applicability of the present bridging method at various particle radii. Using the present bridging method the elastic modulus of the nanocomposites was efficiently obtained with accuracy. In addition, the effect of the interface thickness and modulus on the elastic modulus of the nanocomposite was investigated.