Epoxy Resin 첨가 및 제조공정에 따른 MDF 시멘트 복합재료의 수분안정성 연구

노준석,김태진,박춘근,최상홀 한국세라믹학회 1998 한국세라믹학회지 Vol.35 No.4

HAC/PVA계 MDF 시멘트 복합재료의 수분안정성을 향상시키기 위하여 수용성 epoxy resm을 시멘트 중량에 대해 5wt% 에서 15wt%까지 첨가하고 calendering법, extruding법, warm pressing법으로 성형하여 epoxy resin첨가량 및 제조공정이 수분안정성에 미치는 영향을 살펴보았다. 제조된 시편은 건조상태 및 3일, 7일, 14일간 물 속에 침적 후 습윤강도를 3점 곡강도로 측정하고 SEM으로 표면 가까운 부분의 파단면을 관찰하고 수은압입법으로 기공분포 및 기공율을 분석하여 침수 재령벌 MDF 시멘트 복합재료의 미세조직 변화를 살펴보았다. 적량의 epoxy resin 첨가에 의해 건조강도는 감소하였으나 전반적으로 수분안정성이 향상되었다. 그러나 전반적으로 epoxy의 함량이 많아지면 초기건조강도는 감소하는 경향을 나타나었으며 epoxy 첨가량이 7wt% 이상일 경우에서는 수분안정성 역시 별다른 효과를 볼 수 없었다. 제조공정별로는 warm pressing법에 의해 성형된 경우 epoxy 첨가에 의한 강도 및 수분안정성 향상 효율이 다른 방법보다 월등히 뛰어났으며 epoxy resinmdmf 5wt%, 7wt% 첨가하였을 때, 최적의 강도 및 수분안정성 효과를 얻을 수 있었다. The effect of epoxy resin on the water stability of HAC/PVA based MDF cement composite were stu-died through the three different forming methods calendering extruding and warm pressing. In prexing step the epoxy resin was added in 5-15wt% of cement weight. The 3-point flexural strength of each dry and wet specimen which were immersed in water during 3. 7, 14 days was estmated and the mi-crostructural change of epoxy resin-added MDF cement composite due to water immersion was charac-terized by scanning electron microscopy. As the addition amount of epoxy resin the im-provement of water stability of MDF cement composite was achieved in most case. Especially through the warm press forming method the effectiveness of epoxy resin addition to the water stability was enhanced. When the epoxy resin was added by 5wt% to 7wt% the optimum flexural strength and water stability

고온 시효 시험에 따른 Epoxy 솔더 접합부의 접합 특성 평가

강민수,김도석,신영의 한국전기전자재료학회 2019 전기전자재료학회논문지 Vol.32 No.1

고온에 노출된 무연솔더 접합부는 금속간화합물이 성장하여 접합특성을 저하시킨다. 접합특성 저하를 보완하기 위해 에폭시가 함유된 솔더페이스트를 통해 솔더 접합부를 형성하였으며, 고온에의한 접합특성 저하를 비교 분석하였다. 실험시편은 R3216 규격 Chip으로 SAC305, Sn58Bi와 Epoxy를 함유한 솔더페이스트를 준비하여 OSP 마감된 PCB에 리플로우 공정을 통해 접합하였다. 솔더접합부의 고온의 접합특성을 분석하기 위해 150도의 고온 시효 시험을 14day(336h) 수행하였으며, 전단력 측정을 통해 접합특성을 비교 분석하였다. Epoxy를 함유한 솔더를 사용하여 접합공정을 수행한 결과, 솔더 접합부 외각 및 Chip과 Cu pad 사이에 Epoxy 경화가 발생하여 Epoxy 필렛을 형성하였다. 고온 시효 시험 후 솔더 접합부에는 Cu6Sn5의 금속간화합물이 형성되었으며, 이로 인해 기존의 솔더접합부의 전단력은 크게 감소하였다. 그러나 에폭시 솔더가 함유된 솔더 접합부의 전단력 저하는 크게 나타나지 않았으며, 솔더 접합부 외각에 경화된 Epoxy가 솔더 접합부를 지지하여 솔더 내부의 금속간화합물이 성장하였음에도 전단력의 저하는 크지 않았다. 에폭시를 통해 솔더 접합부에서 형성되는 금속간화합물 등 금속학적 조직변화에 대응하여 높은 접합특성을 확보할 수 있다. Bonding properties of epoxy-containing solder joints were investigated by a high temperature aging test. Specimens were prepared by bonding an R3216 standard chip resistor to an OSP-finished PCB by a reflow process withtwo basic types of solder (SAC305 & Sn58Bi) pastes and two epoxy-solder (SAC305+epoxy & Sn58Bi+epoxy) pastes. In all epoxy solder joints, an epoxy fillet was formed in the hardened epoxy, lying around the outer edge of the solderjoint, between the chip and the Cu pad. In order to analyze the bonding characteristics of solder joints at hightemperatures, a high-temperature aging test at 150℃ was carried out for 14 days (336 h). After aging, the intermetalliccompound Cu6Sn5 was found to have formed in the solder joint on the Cu pad, and the shear stress on the conventionalsolder joint was reduced by a significant amount. The reason that the shear force did not decrease much, even thoughin epoxy solder, was thatbecause epoxy hardened at the outer edge of the supported solder joints. Using epoxy solder,strong bonding behavior can be ensured due to this resistance to shear force, even in metallurgical changes such as thosewhere intermetallic compounds form at solder joints.

Solid Epoxy를 이용한 패키지 및 솔더 크랙 신뢰성 확보를 위한 실험 및 수치해석 연구

조영민,좌성훈,Cho, Youngmin,Choa, Sung-Hoon 한국마이크로전자및패키징학회 2020 마이크로전자 및 패키징학회지 Vol.27 No.1

반도체 패키지에서 언더필의 사용은 패키지의 응력 완화 및 습기 방지에 중요할 뿐만 아니라, 충격, 진동 시에 패키지의 신뢰성을 향상시키는 중요한 소재이다. 그러나 최근 패키지의 크기가 커지고, 매우 얇아짐에 따라서 언더필의 사용이 오히려 패키지의 신뢰성을 저하하는 현상이 발견되고 있다. 이러한 이슈를 해결하기 위하여 본 연구에서는 언더필을 대신 할 소재로서 solid epoxy를 이용한 패키지를 개발하여 신뢰성을 향상시키고자 하였다. 개발된 solid epoxy를 스마트 폰의 AP 패키지에 적용하여 열사이클링 신뢰성 시험과 수치해석을 통하여 패키지의 신뢰성을 평가하였다. 신뢰성 향상을 위한 최적의 solid epoxy 소재 및 공정 조건을 찾기 위하여 solid epoxy 의 사용 개수, PCB 패드 타입 및 solid epoxy의 물성 등, 3 개의 인자가 패키지의 신뢰성에 미치는 영향을 고찰하였다. Solid epoxy를 AP 패키지에 적용한 결과 solid epoxy가 없는 경우 보다, solid epoxy를 적용한 경우가 신뢰성이 향상되었다. 또한 solid epoxy를 패키지의 외곽 4곳에 적용한 경우 보다는 6 곳에 적용한 경우가 더 신뢰성이 좋음을 알 수 있었다. 이는 solid epoxy가 패키지의 열팽창에 따른 응력을 완화 시키는 역할을 하여 패키지의 신뢰성이 향상되었음을 의미한다. 또한 PCB 패드 타입에 대한 신뢰성을 평가한 결과 NSMD (non-solder mask defined) 패드를 사용할 경우가 SMD (solder mask defined) 패드 보다 신뢰성이 더 향상됨을 알 수 있었다. NSMD 패드의 경우 솔더와 패드가 접합하는 면적이 더 크기 때문에 구조적으로 안정하여 신뢰성 측면에서 더 유리하기 때문이다. 또한 열팽창계수가 다른 solid epoxy를 적용하여 신뢰성 평가를 한 결과, 열팽창계수가 낮은 solid epoxy를 사용한 경우가 신뢰성이 더 향상됨을 알 수 있었다. The use of underfill materials in semiconductor packages is not only important for stress relieving of the package, but also for improving the reliability of the package during shock and vibration. However, in recent years, as the size of the package becomes larger and very thin, the use of the underfill shows adverse effects and rather deteriorates the reliability of the package. To resolve these issues, we developed the package using a solid epoxy material to improve the reliability of the package as a substitute for underfill material. The developed solid epoxy was applied to the package of the application processor in smart phone, and the reliability of the package was evaluated using thermal cycling reliability tests and numerical analysis. In order to find the optimal solid epoxy material and process conditions for improving the reliability, the effects of various factors on the reliability, such as the application number of solid epoxy, type of PCB pad, and different solid epoxy materials, were investigated. The reliability test results indicated that the package with solid epoxy exhibited higher reliability than that without solid epoxy. The application of solid epoxy at six locations showed higher reliability than that of solid epoxy at four locations indicating that the solid epoxy plays a role in relieving stress of the package, thereby improving the reliability of the package. For the different types of PCB pad, NSMD (non-solder mask defined) pad showed higher reliability than the SMD (solder mask defined) pad. This is because the application of the NSMD pad is more advantageous in terms of thermomechanical stress reliability because the solderpad bond area is larger. In addition, for the different solid epoxy materials with different thermal expansion coefficients, the reliability was more improved when solid epoxy having lower thermal expansion coefficient was used.

Metal Copper Clad Laminate (MCCL)의 고방열 특성을 위한 Epoxy/BN 복합체 개발

최호경,최재현,최봉구,윤도영,최중소 한국화학공학회 2020 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.58 No.1

In this study, metal copper clad laminate can be prepared using epoxy composite filled with thermally conductive fillers. In order to improve the thermal conductivity of epoxy composites, it is important factor to form conductive networks through appropriate packing of conductive fillers in epoxy composite matrix and to decrease the amount of thermally resistant junctions involving a epoxy composite matrix layer between adjacent filler units. This is because epoxy has a thermal conductivity of only 0.2-0.3W, so in order to maintain high thermal conductivity, thermally conductive fillers are connected to each other, so that the gap between particles can be reduced to reduce thermal resistance. The purpose of this study is to find way to achieve highly thermally conductive in the epoxy composite matrix filled with Al2O3 and Boron Nitride(BN) filler by filler loading and uniform dispersion. As a results, the use of Al2O3/BN hybrid filler in epoxy matrix was found to be effective in increasing thermal conductivity of epoxy composite matrix due to the enhanced connectivity offered by more continuous thermally conductive pathways and uniform dispersion without interfacial voids in epoxy composite matrix. In addition, surface treatmented s-BN improves the filler dispersion and adhesion between the filler and the epoxy matrix, which can significantly decrease the interfacial thermal resistance and increase the thermal conductivity of epoxy composite matrix. 본 연구에서는, 열 전도성 충진제로 충진 된 에폭시복합체를 사용하여 금속 구리판에 이를 코팅한 기판이 제조되었다. 에폭시 복합체의 열전도도를 향상시키기 위해서는 에폭시 매트릭스에 있는 전도성 필러의 최적 분산을 통한전도성 네트워크를 형성하게 하고, 인접한 필러 입자들 사이에서 열 저항 접합의 수를 감소시키는 것이 중요한 요소이다. 이는 에폭시는 열전도도가 0.2~0.3W 밖에 안되기 때문에 높은 열전도도를 유지하기 위해선 열전도성 필러가서로 연결되어 입자간에 갭이 적어야 열저항을 감소시킬수 있기 때문이다. 본 연구의 목적은 에폭시 수지에 Al2O3와Boron Nitride (BN) 충진제를 균일하게 분산시켜 고방열 에폭시 복합체를 개발하는 데 있다. 그 결과, Al2O3와 Boron nitride Filler가 에폭시 수지 매트릭스에 서로 연결되어 에폭시 수지와 알루미나/Boron nitride 하이브리드 필러 간에계면 공극 없이 분산되어 열전도도 특성 향상을 확인 할 수 있었고, 표면 처리한 s-BN 필러가 에폭시 수지의 매트릭스의 계면접착력을 향상시켰으며, 계면 공극을 최소화함에 따라 높은 열전도도 특성을 확보 할 수 있었다.

Flexural behavior of carbon nanotube-modified epoxy/basalt composites

Man-Tae Kim,Kyong-Yop Rhee 한국탄소학회 2011 Carbon Letters Vol.12 No.3

The use of carbon nanotubes (CNTs) as a reinforcing material in a polymer matrix has increased in various industries. In this study, the flexural behavior of CNT-modified epoxy/basalt (CNT/epoxy/basalt) composites is investigated. The effects of CNT modification with silane on the flexural properties of CNT/epoxy/basalt composites were also examined. Flexural tests were performed using epoxy/basalt, oxidized CNT/epoxy/basalt, and silanized CNT/epoxy/basalt multi-scale composites. After the flexural tests, the fracture surfaces of the specimens were examined via scanning electron microscopy (SEM) to investigate the fracture mechanisms of the CNT/epoxy/basalt multi-scale composites with respect to the CNT modification process. The flexural properties of the epoxy/basalt composites were improved by the addition of CNTs. The flexural modulus and strength of the silane-treated CNT/epoxy/basalt multi-scale composites increased by approximately 54% and 34%, respectively, compared to those of epoxy/basalt composites. A SEM examination of the fracture surfaces revealed that the improvement in the flexural properties of the silane-treated CNT/epoxy/basalt multi-scale composites could be attributed to the improved dispersion of the CNTs in the epoxy.

Preparation of ultra-low CTE epoxy composite using the new alkoxysilyl-functionalized bisphenol A epoxy resin

Chun, Hyunaee,Kim, Yun-Ju,Tak, Sang-Yong,Park, Sook-Yeon,Park, Su-Jin,Oh, Chang Ho Elsevier 2018 Polymer Vol.135 No.-

<P><B>Abstract</B></P> <P>The high <I>coefficient of thermal expansion</I> (CTE) of the epoxy composite frequently causes the CTE-mismatch problem in semiconductor packaging. However, when the <I>epoxy resins available currently</I> are used for composite, the CTE-mismatch problem is inevitable even at the highly-filled conditions. In this study, the new type of bisphenol A (BPA) epoxy resin, <I>i.e., ethoxysilyl-functionalized</I> BPA epoxy was synthesized for the ultra-low CTE epoxy composite. The new epoxy composite with 85 wt% of silica content showed the ultra-low CTE of 3.2 ppm/°C and 6.0 ppm/°C at the temperature ranges of T < T<SUB>g</SUB> and T > T<SUB>g</SUB>, respectively. For comparison, the <I>non-functionalized</I> BPA epoxy composite was prepared under the similar conditions and it showed the CTE values of 8 ppm/°C and 40 ppm/°C at the temperature ranges of T < T<SUB>g</SUB> and T > T<SUB>g</SUB>, respectively. In order to understand the unique feature of the alkoxysilyl-functionalized epoxy, the reaction mechanism of the new epoxy was investigated using the model compound.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New class of epoxy resin, <I>i.e,</I> alkoxysilyl-functionalized epoxy is synthesized. </LI> <LI> The epoxy composite shows the ultra-low CTE of 4.6 ppm/°C, slightly higher than wafer. </LI> <LI> The curing mechanism is studied in order to understand unique feature of new epoxy. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Tensile and Electrical Insulation Properties of Epoxy/Micro‑silica Composites

박재준 한국전기전자재료학회 2019 Transactions on Electrical and Electronic Material Vol.20 No.1

The effect of epoxy species on the tensile and electrical insulation properties of epoxy/micro-silica composites was studied by using three species of epoxy resins for high voltage insulators. The mixing ratio of spherical type micro-silica was varied at 40–70 wt% in each epoxy systems. Tensile strength of three Epoxy/micro-silica composites was lower than that of the each neat epoxy system and increased with increasing micro-silica content in each system. The maximum tensile strength was 86.0 MPa in Epoxy 2/micro-silica (70 wt%) composite. Electrical insulation breakdown strength of three Epoxy 1/micro-silica, Epoxy 2/micro-silica, Epoxy 3/micro-silica composites was higher than that of the each neat Epoxy 1, Epoxy 2 and Epoxy 3. The maximum electrical insulation breakdown strength was 55 kV/2mm in Epoxy 2/micro-silica (50 wt%) composite.

Mechanical Properties of Tow Prepreg Applied to AFP using Surface-tackiness

JaeHyeon Lim,Ki-Young Kim,Joonmyung Choi,Jae-Chul Lee 한국섬유공학회 2022 Fibers and polymers Vol.23 No.6

This study presents the production of a carbon-fiber composite material using a thermosetting epoxy resin andPolyether Sulfone (PESU), a thermoplastic toughening agent. A tow prepreg was fabricated using the proposed hightoughnessresin, and it was applied to the automated fiber placement (AFP) process. To obtain resin with different viscosities,different ratios of solid epoxy YD-011 were mixed with the high-toughness resin, which contained liquid epoxy YD-128 and10 phr of PESU, at certain ratios. The surface-tackiness of each mix of resin was then compared by applying the tow prepregthat was produced to the AFP process. The results indicate that the resin mix that contained 10 % of solid epoxy was the mostsuitable for the AFP process. Subsequently, the mechanical and thermal properties of the resin and tow prepregs using onlythe liquid epoxy containing the PESU were compared with the resin and tow prepregs that contained 10 % solid epoxy. Theresin produced by adding 10 % solid epoxy to the liquid epoxy exhibited improvements of 3 % in tensile strength, 16% intensile modulus, and 27 % in impact strength when compared to the resin that used only the liquid epoxy. Furthermore, thefracture toughness test results using single-edge notched bending and compact tension methods showed a decrease of 10 %and 16% , respectively, and the glass transition temperature decreased by 5 %. In the case of the tow prepreg specimenproduced by adding 10 % solid epoxy to the liquid epoxy, it exhibited a decrease of 0.6% in the 0 ° tensile strength, adecrease of 1.6% in tensile modulus, and an increase of 4 % in the 90 ° tensile strength when compared to the tow prepregthat applied only the liquid epoxy. In addition, the ILSS interfacial strength increased by 1 %, while the double cantileverbeam fracture toughness decreased by 8 %. A comparison of the results showed that the tow prepreg prepared by adding10 % solid epoxy to the liquid epoxy had excellent mechanical properties, and the tow prepregs were laminated mostappropriately in the AFP process, thus verifying its applicability as a resin in tow prepregs for the AFP process. Keywords: Carbon fiber reinforced plastic (CFRP), Automated fiber placement (AFP), Tow prepreg, Toughened

에폭시 레진의 타 재료 배색 효과와 입체적 질감 표현법 연구

한은주 한국기초조형학회 2021 기초조형학연구 Vol.22 No.1

This study focuses on providing various processing information on the formative aspects of epoxy materials by demonstrating the formative and material value of epoxy and providing its method of application through experiments on the color scheme and various methods expressing three dimensional surface texture of epoxy by mixing experiments of epoxy with other materials and by using alginate, latex, and acetate paper, and T7 epoxy. This study expecially places a great emphasis on suggesting the utilization methods of color shemes and texture expressions by using other materials and various molds in expressing the surface image of epoxy. Since the scope of each experiment's material selection is so wide, this study uses a method of representative selection of what is considered highly useful for representing color effects and stereoscopic textures through various experiments, organizing and charting the results. The types of epoxy are divided into various types depending on hardness and transparency, but in this study, only #A epoxy and T7 epoxy are selected for experiments because the threedimensional texture expression using color combination effect by mixing of other materials and molding is the key process of the study. Epoxy has a properties of solidifying in the liquid state, so finding effective ways to express various colors and textures for its characteristics is the most important issue. This is because if these two conditions are all satisfied, the value of use as a formative material will be much higher. As a result, through this experimental process, it was possible to derive various approaches of three-dimensional texture and color scheme using epoxy. Of course, epoxy material has many variables depending on its type and the mixture materials. Therefore, the efforts should be made to secure more experiments and the number of cases for them, and to increase the utilization of materials. This researcher, intend to continue these studies on materials constantly to be of practical help to those who are in the formative arts. 본 연구는 에폭시와 타 재료의 혼합 실험과 알지네이트, 라텍스 및 아세테이트지를 이용해 에폭시의배색 방법과 입체적 표면 질감을 표현하는 다양한 방법에 대한 실험과 T7 에폭시를 이용한 다양한 입체 질감 표현에 대한 실험을 통해 에폭시 재료의 조형 재료적 가치를 증명하고 그 활용 방법을 제공함으로써 에폭시 재료에 대한 조형적 측면의 다양한 가공 정보를 제공하는 것에 목적이 있다. 본 연구에서는 에폭시의 표면 이미지 표현에 있어 타 재료와 다양한 틀의 가공을 이용해 배색 표현과 입체적 질감 표현의 활용방안을 제시하는 것에 중점을 둔 연구이다. 각 실험의 재료 선택에 있어 그 범위는 매우 넓기 때문에 본 연구에서는 여러 가지 실험을 통해 배색 효과와 입체적 질감을 나타내는 데에 활용성이 높다고 판단되는 것을 대표적으로 선정하여 본 연구의 결과물로 정리하고, 그 결과를 도표화하는방식을 사용한다. 에폭시의 종류는 경도, 투명도에 따라 다양한 종류로 구분되지만 본 연구에서는 타재료의 혼합을 이용한 배색 효과와 틀 성형 등을 이용한 입체적 질감표현이 연구의 핵심 과정이기에에폭시는 #A 에폭시와 T7 에폭시만을 선정하여 실험을 진행한다. 에폭시는 액상의 상태에서 고체화되는 특성을 가진 재료이기에, 그 특성에 맞게 다양한 색과 질감을 표현하는 효과적 방법을 찾는 것이가장 중요한 쟁점이다. 이 두 가지 조건이 만족하면, 조형 재료로써 활용 가치가 높아지기 때문이다. 결론적으로 이 실험 과정을 통해 에폭시를 이용한 다양한 입체적 질감과 배색의 다양한 접근 방식을도출할 수 있었다. 물론 에폭시는 변수가 많은 재료이기에 더욱 많은 실험과 그에 대한 경우의 수를확보하여 재료의 활용성을 높이는 노력이 필요하다. 본 연구자는 이러한 재료 연구를 꾸준히 이어나가조형을 하는 이들에게 실질적 도움이 되는 연구를 지속하고자 한다.

Epoxy를 사용한 수분산 폴리우레탄의 합성 및 물성

박지연 ( Ji Yeon Park ),정부영 ( Boo Young Jeong ),천정미 ( Jung Mi Cheon ),하창식 ( Chang Sik Ha ),천제환 ( Jae Hwan Chun ) 한국접착및계면학회 2015 접착 및 계면 Vol.16 No.1

본 연구에서는 수분산 폴리우레탄의 내가수분해성 및 접착력을 향상시키기 위하여 polyester polyol,epoxy resin, 4,4-dicyclohexylmethane diisocyanate (H12MDI), dimethylol propionic acid (DMPA)를 사용하여 epoxy를 함유한 수분산 폴리우레탄을 합성하였다. 또한 합성된 수분산 폴리우레탄의 물성은 DSC, UTM, adhesion test 등을 통해 평가하였다. 합성된 수분산 폴리우레탄의 Tg는 -50°C 부근에서 나타났으며, epoxy resin의 함량이 증가함에 따라 Tg도 상승하는 결과를 나타내었다. Epoxy resin의 함량이 증가함에 따라 인장강도는 증가하였고, 신율은 감소하였다. 또한 접착력 및 내가수분해 접착력은 polyol : epoxy = 99 : 1에서 최고값을 나타내었다. In this study, Waterborne polyurethanes (WPU) using Epoxy group were synthesized with polyester polyol, epoxy resin, 4,4-dicyclohexylmethane diisocyanate (H12MDI), dimethylol propionic acid (DMPA) to improve the hydrolysis resistance and adhesion. In addition, the properties of the synthesized waterborne polyurethane was evaluated through DSC, UTM, adhesion strength. Tg of the synthesized waterborne polyurethane is shown in the vicinity of -50°C. Tg were increased with as epoxy resin contents increased. The tensile strength was increased as the content of epoxy resin increases, elongation was decreased. Optimum adhesion and hydrolysis- resistance strength were obtained when polyol : epoxy ratio was 99 : 1.