• Applied Biological Chemistry
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• v.39 no.2
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• pp.123-126
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• 1996

Simple and rapid method of purification of plasma proteins from bloods of slaughtered animals was developed and the proteins were applied to plywood products as a blood 히ue to utilize waste materials. Plasma protein was obtained by adding 2% trichloroacetic acid (TCA) or 0.6 N HCI as optimal concentration to the supernatant, after centrifugation of bloods. Molecular properties of beef and pig plasma proteins were examined on SDS-PAGE. Application of blood glue to plywood was quite satisfactory compared to the synthetic amino resin by tensile-shear test for the strength of adhesive bonding.

• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.536-542
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• 1996

Water-based acrylic sizing agent(GSW-7000) was prepared by emulsion copolymerization for sizing polyester yarns. Ammonium salt version of the acrylic sizing agent offered greater abrasion resistance to weaving forces and water resistance for water jet loom. GSW-7000 exhibited proper viscosity for sizing, high penetration ability and excellent adhesion to polyester yarn. It was possible to reduce the size pick-up to 70~80% of ordinary solvent-based sizing agent due to excellent adhesive strength of GSW-7000.

• Transactions of the Society of Information Storage Systems
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• v.5 no.2
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• pp.82-88
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• 2009

Understanding the adhesion behavior and characteristics of toner film is required to achieve image and text printing with high quality resolution. Toner can be considered as a thin film coating on a media such as paper or polymer film. Quantitative measurement of adhesion characteristics of the thin film is important to assess the reliability of the system. In this work the main objective was to investigate the adhesion characteristic between the toner and the media by ramp loading scratch test method. The scratch test may be used to obtain quantitative information about the adhesion of the film to the substrate. In the scratch test a diamond tip was used to scratch the surface of the toner film under an increasing normal load until the toner detached or fractured. The critical load (LC) was obtained from the experimental results. Also, the relationship between the critical load and the adhesive strength of the interface between the substrate and the toner was obtained by measuring the normal and tangential forces during the scratch test. Finally, theoretical analysis of the toner scratch characteristics was performed based on Benjamin and Weaver theory, Plowing model, and Laugier model.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.6
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• pp.627-634
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• 2007

A bonded plate or a coated part can be debonded by external impact or thermal expansion. To analyse adhesive strength, the blister test is generally adopted. In this paper, a blister test is modelled theoretically and then the stability and bifurcation of the blister are studied under several different cases. The blister is simplified to consist of a pure bending plate attached elastically to the rigid substrate. Expression of the energy release rate is obtained as a form of an explicit function for a circular-type blister or tunnel-type blister grown by controlling the internal pressure or internal volume. Stability and bifurcation are also studied in the frame of the quasi-static evolution. The study shows that the circular- type blister propagates with the first mode of bifurcation and that the tunnel-type blister propagates with a regular wave. It is proved that the waves have the same form on two side lines of the tunnel and that the wave length can be obtained. When the internal pressure is controlled, the blister is unstable, but when the internal volume is controlled, it is stable.

• Journal of Power System Engineering
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• v.22 no.1
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• pp.64-71
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• 2018

Currently, functional patterns are formed by screen printing on stretchable films, and they are applied to wearable and stretchable devices. In this study, three types of silver paste were prepared using three polyester binders with different Tg and molecular weights in order to impart elasticity to the conductive pattern itself. Rheological properties and DSC measurements were performed for each silver paste. Then, each silver paste was screen printing and cured by an IR dryer to evaluate adhesive strength, pencil hardness, resistance and surface shape change according to strain. As a result, it was found that the silver paste using a binder with a low Tg and a high molecular weight has the smallest resistance change depending on the strain. Namely, it was found that it is most preferable to use a binder with a low Tg and a high molecular weight as the stretchable electrode.

• Journal of Welding and Joining
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• v.35 no.3
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• pp.15-20
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• 2017

In this paper, two types of assemblies using CNT-filled SACAs (with 0.03 wt% CNTs and without CNT) were prepared to investigate the influence of carbon nanotubes (CNTs) on the reliability properties of solderable anisotropic conductive adhesives (SACAs) with a low-melting-point alloy (LMPA). Two types of reliability test including thermal shock (TS: -55 to $125^{\circ}C$, 1000 cycles) and high-temperature and high-humidity (HTHH: $85^{\circ}C$, 85% RH, 1000 h) tests were conducted. The SACA assemblies with and without CNTs showed stable electrical reliability properties due to the formation of wide and stable metallurgical interconnection between corresponding metallizations by the molten LMPA fillers. Although the mechanical pull strength of CNT-filled SACA assemblies was decreased after thermal aging (because of the excessive layer growth and planarization of the IMCs), the CNT-filled SACA with 0.03wt% CNTs showed enhanced mechanical reliability properties compared with the SACA assemblies no CNTs. This enhancement in mechanical performance was due to the reinforcement effect of the CNTs. These results demonstrate that CNTs within the CNT-filled SACAs can improve the reliability properties of CNT-filled SACAs joints due to their superior physical properties.

• Fibers and Polymers
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• v.3 no.4
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• pp.153-158
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• 2002

A series of waterborne polyurethanes (WBPU) were prepared from 4,4-dicyclohexylmethane diisocyanate ($H_{12}$MDI),2,2-bis(hydroxylmethyl) propionic acid (DMPA), othylenediarnine (EDA), triethylamine (TEA), and triblock glycol [TBG, ($\varepsilon$-caprolactone)$_{4.5}$-poly(tetramethylene ether) glycol (MW= 2000)-($\varepsilon$-caprolactone)$_{4.5}$: $(CL)_{4.5}$-PTMG-$(CL)_{4.5}$, MW=3000] as a soft segment. Two melting peaks of TBG at about 14$^{\circ}C$ and 38$^{\circ}C$ were observed indicating the presence of two different crystalline domains composed of CL and PTMG dominant component. The effect of soft segment content (60-75 wt%) on the colloidal properties of dispersion, and thermal and mechanical properties of WBPU films, the water vapor permeability (WVP) and water resistance (WR) of WBPU-coated Nylon fabrics, and the adhesive strength of WBPU- coated layer and Nylon fabrics was investigated. As soft segment contents increased, the water vapor permeability of WBPU- coated Nylon fabrics increased from 3615 to 4502 g/$m^2$day, however, the water resistances decreased from 1300 to 500 mm$H_2$O.O.

• Journal of Ocean Engineering and Technology
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• v.10 no.2
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• pp.88-97
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• 1996

The pupose of this study is to improve the mechanical properies and to evaluate the residual stresses of flame-sprayed Alumina ceramic coating layer. The first work in this study is to investigate the effects of strengthening heat treatments on the mechanical properties of coating layer. Strengthening heat treatments for sprayed specimens were carried out in vaccum furnace. The mechanical properties such as microhardness, thermal shock resistance, adhesive strength and erosion resistance were tested for the sprayed specimens after strengthening heat treatments. And it was clear that the mechanical properties of coating layer were much improved by strengthening heat treatments. The second work in this study is to evalute the residual stresses in coating lsyer by numerical analysis. FDM and FEM were used to analyze temperature distribution and residul stresses in coating layer. It was proved that are tensile stresses in coating layer and that residual stresses can be controlled by the appropriate selection of the spraying parameters such as preheat temperature, coating thickness and bond coat thickness.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.729-732
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• 2010

본 논문에서는 이산 변수 최적화에 적합한 유전 알고리듬을 이용하여 복합재 적층 패치의 최적강도설계를 수행하였다. 기저판(substrate)와 접착제(adhesive), 그리고 복합재 적층 패치로 이루어진 구조물에서 패치의 강도를 효율적으로 구하기 위해서 응력 함수 기반의 해석적 방법을 도입하였다. 면외 방향의 응력 함수를 가정하여 가상 공액일의 법칙(complementary virtual work principle)에 적용하였으며, 복합재 패치의 자유 경계조건으로부터 면내 방향의 응력함수를 결정하였다. 응력 함수를 통하여 구한 층간 응력 값은 자유 경계 효과를 잘 나타내었고, 이를 이용하여 패치의 강도 해석을 수행하였다. 강도 해석 시, 복합재 패치의 파괴 기준은 면내 응력들에 대해서는 최대 응력 척도를 사용하였으며, 층간 응력들에 대해서는 quadratic delamination 척도를 사용하였다. 유전 알고리듬을 이용한 최적강도설계 과정에서는 임의의 염색체가 주어진 적층 구속 조건을 만족할 수 있게 수정(repairing)하는 과정을 도입하였다. 또한 다수의 전역해(global optima)를 효과적으로 찾기 위해서 multiple elitism 기법을 도입하였다. 응력 함수 기반의 강도 해석방법과 유전 알고리듬과의 연계를 통한 복합재 적층 패치의 강도최적설계 기법은 패치 구조물의 해석 및 설계에 있어서 효율적인 도구로서 사용할 수 있을 것이라 사료된다.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.781-784
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• 2004

Method of Steel plate reinforced by fiber sheet is advantageous in the secure loading facility. For this method are a light weight and a high strength, the thickness of steel can be reduced Effects of composite system are depreciated when the thickness of steel is thin. This is the result of the difference of ductility ratio with steel plate. Steel plate reinforced by fiber sheets confirms the ability of transformation. This is the result of the property of steel materials Steel plate reinforced by fiber sheet didn't display an enough performance when theadhesives are epoxy rosin. This is the result of the slide of the surface of stee1. The adhesive ability is varied by the number and span of anchor bolts. There wasn't happening the separation between steel and epoxy. Thus the method used in combination with anchor and epoxy is best excellent. This is the result of the upward of accumulation effects Shearing force is in proportion to the number of bolts. But the ability of shearing force per one bolt is reducing. Thickness of steel plate reinforced by fiber sheet must be designed so that steel is endure before concrete is wreck.