• Title/Summary/Keyword: Glass stability

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Effect of Acrylonitrile Content on the Glass Transition Temperature and Melt Index of PVC/SAN Blends

  • Liu Wang;Kim Hwan-Chul;Pak Pyong-Ki;Kim Jong-Chun
    • Fibers and Polymers
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    • v.7 no.1
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    • pp.36-41
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    • 2006
  • PVC and SAN are often mixed to compensate for the disadvantages of each polymer. Miscibility and thermal stability of PVC/SAN blend were investigated in this study by blending SAN polymer having 20, 24, 28, 32 % of acrylonitrile contents. Two polymers were mixed using a melt blending method with a single screw extruder. DSC thermogram was used to evaluate miscibility of the two polymers. SAN having 24 % of acrylonitrile showed the best miscibility with PVC. In order to evaluate degradation behavior, blended polymer was heat treated in DSC furnace and glass transition temperature was measured consecutively. Glass transition temperature increased continuously with annealing time due to degradation and cross-linking of polymer chains. Melt index of blended polymer was always higher than that of PVC.

A Study on the Acryl Object as Artistic element to the Furniture - Centering around the subject of WINIER, MOUNT, SPRING - (가구의 조형적 요소로서 아크릴 Object에 관한 연구 -겨울, 산, 샘의 주제를 중심으로-)

  • 김광렬
    • Journal of the Korea Furniture Society
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    • v.12 no.2
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    • pp.61-71
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    • 2001
  • In furniture design, it is very important to choose adequate materials. Transparent materials provide expectations and reveals unique effects unlike others. As transparent materials, glass and acrylic have light and fresh impression from their transparency, and are frequently used in structuring neat space. Despite its good merits, glass is not able to satisfy designers desire in making various shape and structure. It has defect in manufacturing process because it requires professional, specialized studio. Compared to glass, acrylic has its merit in processing and stability, and also is very economical. Acrylic is easily used with woodworking tool. In addition, acrylic has unique texture. This study is on the attempt to apply acrylic to the furniture as artistic element.

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The Behavior of Mechanical property of Thermoplastic Composite in Compression Molding (복합재료의 압축성형에 따른 기계적 특성변화)

  • 이중희;이호언
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2000.11a
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    • pp.261-264
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    • 2000
  • The objective of this work was to characterize mechanical properties of thermoplastic composites for various forming condition in compression molding. Randomly oriented long glass fiber reinforced polypropylene(PP) was used in the work. The composite materials contained 20%, 30%, and 40% glass fiber by weight. Compression molding was conducted to make the test specimen. Dimensional stability was measured on each forming condition with the spring-forward angle. Tensile test was conducted to characterize mechanical properties of formed parts in various forming conditions.

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Re-Ir Coating Effect of WC Core Surface for Aspheric Glass Lens Molding (비구면 Glass 렌즈 성형용 초경합금 코어면 Re-Ir 코팅 효과)

  • Kim, Hyun-Uk;Kim, Sang-Suk;Kim, Hye-Jeong;Kim, Jeong-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.441-441
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    • 2007
  • As Rhenium-Iridium{Re-Ir) coating possesses such features as, high hardness, high elasticity, abrasion resistance and chemical stability, there have been exerted continuous efforts in research works in a variety of fields, and this technology has also been applied widely to industrial areas. In this research, the optimal grinding condition was identified using Microlens Process Machine in order to contribute to the development of aspheric glass lens for mobile phone module having 3 mega pixel and 2.5X zoom, and molding core(WC) was manufactured having performed ultra-precision machining. Effects of Re-Ir coating on form accuracy (P-V) of molding core and surface roughness(Ra) were measured and evaluated.

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A Study about Decrease of Oxygen Permeability with Adding Glass Flakes and (3-Aminopropyl)triethoxysilane on Polyimide Films (Glass Flake 및 (3-Aminopropyl)triethoxysilane 첨가에 따른 폴리이미드 필름의 산소투과도 감소 연구)

  • Ha-Yoon Nah;Taehee Kim;Haryeong Choi;Ji-Seoung Kim;Won-Jun Lee;Eunkyung Jeon;Joon Hyuk Lee;Hyung-Ho Park
    • Journal of the Microelectronics and Packaging Society
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    • v.31 no.3
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    • pp.80-86
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    • 2024
  • Polyimide has advantages that are different with other polymers, such as high thermal stability, heat resistance, and high chemical resistance. Various application methods for Polyimide have been studied. In this study, research was conducted to manufacture Polyimide films. While implementing Polyimide films with excellent adhesion and pencil hardness through optimized manufacturing conditions, the applicability as a packaging material was considered by adding glass flakes to reduce oxygen permeability. As a result, Polyimide films with glass flakes and (3-Aminopropyl)triethoxysilane have a thickness of about 50 ㎛ were uniformly implemented, and it was confirmed that the adhesion of Polyimide films was 4B, pencil hardness was 5H, and oxygen permeability was below 8.795 × 10-9 cc/s, respectively.

Sheathless electrospray ionization with integrated metal emitter on microfluidic device (전기 분무 이온화를 이용한 단백질 질량분석용 마이크로 유체 소자의 제작 및 실험)

  • Kim, Min-Su;Joo, Hwang-Soo;Lee, Kook-Nyung;Kim, Byung-Gee;Kim, Yong-Kweon
    • Proceedings of the KIEE Conference
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    • 2004.07c
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    • pp.2102-2104
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    • 2004
  • In this study, sheathless electrospray from PDMS/glass microchips with conducting metal emitter tip is described. A chip-based capillary electrophoresis/mass spectrometry (CE/MS) system has advantages of the CE separation and on-line electrospray detection of peptide solution. We have fabricated a new electrospray ionization(ESI) device composed of the metal emitter tip and CE separation channel monolithically in a glass microchip. The separation channel and metal emitter tip are fabricated using a glass wet etching and gold electro plating process, respectively. The fabricated micro electrospray chip was tested by spraying peptide sample for mass spectrometric analysis. Singlely-charged peak and doublely-charged peak of peptide were detected and further MS/MS fragmentation was performed in each peak. Direct comparisons with conventional glass or fused silica emitters showed very similar performance with respect to signal strength and stability.

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A Study on Sheet Resistance and Temperature Stability of $RuO_2$-based Thick Film Resistors with Varying Glass Composition ($RuO_2$를 기본으로 한 후막 저항체의 유리질 성분에 따른 저항값과 온도 안정성에 관한 연구)

  • Choi, Dong-Wook;Kim, Jun-Chul;Kim, Geun-Young;An, Chul
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.29A no.11
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    • pp.84-90
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    • 1992
  • The dependence of electrical characteristics of RuO$_2$-based thick film resistors on the RuO$_2$ contents, glass composition variation and the firing temperatures was measured. The sheet resistance of resistors decreased as the contents of RuO$_2$ increased and at firing temperatures higher than C, the sheet resistance increased as the firing temperature increased. In case of using lead borosilicate glass-containing $Bi_{2}O_{3}$, the sheet resistance decreased as the contents of $Bi_{2}O_{3}$ increased. TCR changes from negative to positive values as RuO$_2$ contents increased and from positive to negative values as the firing temperature increased. TCR increased to positive values as $Bi_{2}O_{3}$ increased in the glass.

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High Temperature Plastic Deformation Behaviors of the Bulk Metallic Glass Zr-Ti-Cu-Ni-Be Alloy (벌크 비정질 Zr-Ti-Cu-Ni-Be 합금의 고온 소성 변형 특성)

  • Lee K. S.;Ha T. K.;Ahn S. H.;Chang Y. W.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2001.10a
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    • pp.272-276
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    • 2001
  • Multicomponent $Zr_{41.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ bulk matallic glass alloy shows good bulk glass forming ability due to its high resistance to crystallization in the undercooled liquid state.1) In this study, DSC and X-ray diffractometry have been performed to confirm the amorphous structure of the master $Zr_{41.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ alloy. To investigate the mechanical properties and deformation behaviors of the bulk metallic $Zr_{41.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ alloy, a series of compression tests has been carried out at the temperatures ranging from $351^{\circ}C$ to $461^{\circ}C$ and at the various initial strain rates from $2{\times}10^{-4}s^{-1}\;to\;2{\times}10^{-2}s^{-1}$. There are two types of nominal stress-strain curves. The one shows linear stress-strain relationship meaning fracture at maximum stress, the other shows plastic deformation including steady-state flow. Also DSC analysis for the compressed specimens has been performed to investigate the change of thermal stability and crystallization behavior for the various test conditions.

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High Temperature Compressive Deformation Behavior of the Bulk Metallic Glass Zr-Ti-Cu-Ni-Be Alloy (벌크 비정질 Zr-Ti-Cu-Ni-Be 합금의 고온 압축 변형 특성)

  • 이광석;하태권;안상호;장영원
    • Transactions of Materials Processing
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    • v.10 no.7
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    • pp.565-572
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    • 2001
  • It is well known that a multicomponent $Zr_{4l.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ bulk metallic glass alloy shows good bulk glass forming ability due to its high resistance to crystallization in the undercooled liquid state. DSC and XRD have been performed to confirm the amorphous structure of the master alloy. To investigate the mechanical properties and deformation behavior of the bulk metallic $Zr_{4l.2}Ti_{13.8}Cu_{12.5}Ni_{10}Be_{22.5}$ alloy, a series of compression tests has been carried out at the temperatures ranging from $351^{\circ}C$ to $461^{\circ}C$at the various initial strain rates from $2{\times}10^4s^1$ to $2{\times}10^2s^1$. Three types of nominal stress-strain curves have been identified such as linear stress-strain relationship meaning fracture at maximum stress, plastic deformation including stress overshoot and steady-state flow, plastic deformation without stress overshoot depending on the strain rate and test temperature. Also DSC analysis for the compressed specimens was carried out to investigate the change of structure, thermal stability and crystallization behavior for the various test conditions.

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DLC Coating Effect of WC Core Surface Roughness for Glass Molding Lens (Glass Lens 성형용 WC Core 표면조도의 DLC 코팅 효과)

  • Kim, Hyun-Uk;Jeong, Sang-Wha;Lee, Dong-Gill;Kim, Sang-Suk;Kim, Jeong-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.487-488
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    • 2006
  • As DLC coating possesses such features as, high hardness, high elasticity, abrasion resistance and chemical stability, there have been exerted continuous efforts in research works in a variety of fields, and this technology has also been applied widely to industrial areas. In this research work, the optimal grinding condition was identified using Microlens Process Machine in order to contribute to the development of aspheric glass which is to be used for mobile phone module having 2 megapixel and $2.5{\times}$ zoom, and mold core (WC) was manufactured having performed ultra-precision machining and effects of DLC coating on shape accuracy(P-V) of mold core and surface roughness(Ra) as well were measured and evaluated.

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