• 한국물환경학회지
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• 제16권4호
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• pp.469-477
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• 2000

Bisphenol-A (BPA), a known endocrine disruptor, is a main building block of epoxy resin which is widely used as a coating agent in residential water storage tanks. Therefore, BPA leaching from the epoxy resin may have adverse effects on human health. The possibility of BPA leaching from three epoxy resins were tested with a modified KS D 8502 method at 20, 50, 75 and $100^{\circ}C$ in deionized water and the specified test water, respectively. BPA leached to the test water was identified using GC-MS and quantified with GC-FID after a sequential extraction and concentration. The results showed that BPA leaching has occurred in all three samples tested. The quantify of BPA leaching from unit area of epoxy resin coating was in the range of $10.677{\sim}273.120{\mu}g/m^2$ for sample A, 29.737~1734.045 for sample B and 52.857~548.778 for sample C depending on the test temperature, respectively. In general, the amount of BPA leaching increased as the water temperature increases. This result implies a higher risk of BPA leaching to drinking water during a hot summer season. In addition, microbial growth, measured by colony forming units, in epoxy coated water tanks was higher than that in a stainless steel tank suggesting that compounds leaching from epoxy resin may support the growth of microorganisms in a residential water holding tank.

• 조명전기설비학회논문지
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• 제17권2호
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• pp.95-101
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• 2003

본 논문에서는 모의 GIS를 에폭시로 코팅하고, 금속이물 혼입시의 부분방전, 부상전압, 절연파괴전압 등을 측정하여, 코팅하지 알았을 경우와 비교 분석하였다. 또한, 여러 경우의 절연사고를 모의하기 위해, SF$_{6}$/$N_2$가스 혼합비, 금속이물의 재질, 직경, 코팅두께, 압력 등을 변화시키면서 전기적특성을 관찰하였다. 실험결과, 코팅두께가 증가할수록 부분방전개시전압이 증가하였으며, 부분방전의 크기는 감소하였다. 또한 철합금 파티클의 부상전압이 구리파티클보다 높았으며, 직경이 증가할수록 부상전압도 증가하였으며, 코팅두께가 두꺼워질수록 절연파괴 전압이 증가하였다. 이상의 연구결과 GIS를 에폭시로 코팅함으로써 절연성능을 향상시킬 수 있음을 확인하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.325-330
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• 1999

The objectives of this study were to compare the development of compressive strength of epoxy resin mortars used as repairing materials with respect to maturity, and to propose a predictive model for strength development of epoxy resin mortar. A series of tests were carried out for the hardener contents of 30, 40 and 50 percentage of resin and compressive strength were measured at the of 6, 12, 24, 72, 120 and 168 hours respectively under temperature of 0, 10, 20 and 3$0^{\circ}C$. The datum temperature was estimated by measured strength, and the maturity is calculated with the estimated datum temperature. The compressive strength of epoxy resin mortar could be predicted by regression analysis from the maturity-compressive strength relationship.

• Elastomers and Composites
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• 제43권1호
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• pp.39-48
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• 2008

상용 에폭시 수지의 접착력은 XNBR을 첨가함으로써 달성할 수 있으나 이는 필연적으로 유리전이온도(Tg)의 감소를 수반하여 접착제의 내열성을 저하시킨다. 1,3-bis(3-aminopropyl) tetramethyldisiloxane과 hydroxy phthalic anhydride를 반응시켜 siloxane-imide를 합성하고, 이를 상용 에폭시 수지와 공중합시켜 변성 에폭시 수지를 합성하였다. 변성 에폭시 수지의 siloxaneimide 함량을 결정하기 위하여 접착력 및 유리전이온도를 2관능성 에폭시 수지의 경우와 비교하여 조성비를 정하였다. Siloxane-imide와 공중합된 30% 변성 에폭시 수지는 5% XNBR을 첨가한 경우 0.42 N/mm의 박리 강도와 $155^{\circ}C$의 유리전이온도를 나타내어 die-bond용 접착제에 요구되는 물성 값인 0.3 N/mm 이상의 박리 강도와 $150^{\circ}C$ 이상의 유리전이온도를 충분히 만족 시킴을 알 수 있었다. 변성 에폭시 수지의 내 산성, 내 알칼리성 및 내습성을 평가한 결과 벤젠 링과 이미드 링의 영향으로 산, 염기 조건에서는 상용 에폭시 수지 대비 무게 변화폭이 감소하였지만 수분 조건에서는 무게 변화폭이 증가한 것을 알 수 있었다. 5% XNBR을 첨가한 30% 변성 에폭시 수지의 경우, 인장응력과 신장률이 상용 에폭시 수지 대비 약 220% 향상되었는데 이는 siloxane의 유연한 성질 때문인 것으로 판단된다.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2004년도 추계학술발표대회 논문집
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• pp.96-99
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• 2004

Silica fillers were coated by plasma polymer coatings of 1,3-diaminopropane, allylamine, pyrrole, 1,2-epoxy-5-hexene, allyl mercaptan and allyl alcohol using RF plasma (13.56 MHz). The coated fillers were then mixed with biphenyl epoxy, phenol novolac (curing agent) and/or triphenylphosphine (catalyst), and subjected to DSC analyses in order to elucidate the chemical reaction between functional moieties in the plasma polymer coatings and the epoxy resin. Only the samples with 1,3-diaminopropane and allylamine plasma polymer coated silica fillers showed heat of reaction peaks when they were mixed with biphenyl epoxy resin only, while these samples as well as the samples with 1,3-diaminopropane, allylamine and pyrrole plasma polymer coated silica fillers exhibited heat of reaction peaks when mixed with both biphenyl epoxy and phenol novolac (curing agent).

• Advanced Composite Materials
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• 제17권4호
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• pp.333-341
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• 2008

A novel manufacturing method for hybrid composites filled with carbon nanotubes (CNTs) and aramid fibers is proposed. To disperse the CNTs in the epoxy matrix with the presence of aramid fibers, CNT/polyethyleneoxide (PEO) composites are prepared and utilized because PEO is miscible in the epoxy resin. After thin films are made of the CNT/PEO composite and placed together with the aramid fibers, the epoxy resin is infused to them. The PEO is dissolved in the epoxy and then the CNTs are dispersed in the PEO/epoxy matrix between aramid fibers before the pre-heated matrix is cured. It is found that the PEO is completely miscible with the epoxy resin and CNTs are dispersed well in the space between the aramid fibers.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.465-468
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• 2006

This paper investigates the effect of curing conditions on the strength improvement of polymer-modified mortars using epoxy resin with various curing methods. The polymer-modified mortars using epoxy resin are prepared with various polymer-cement ratios, and subjected to standard, hot water, heat cure and autoclave cures. The epoxy-modified mortars are tested for flexural and compressive strengths at desired curing methods. From the test results, the flexural and compressive strengths of the epoxy-modified mortars are hardly improved by the autoclave and hot water cures compared to the ideal cure of $20^{\circ}C$. Among the four types of curing methods, the strengths of the heat cured epoxy-modified mortars is largely improved. Especially, it is obtained in the mortars sealed with PVDC film.

• Carbon letters
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• 제15권1호
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• pp.32-37
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• 2014

Multi-walled carbon nanotube (MWCNT)/epoxy composites are prepared by a vacuum assisted resin transfer molding (VARTM) method. The mechanical properties, fracture surface morphologies, and thermal stabilities of these nanocomposites are evaluated for epoxy resins with various amounts of MWCNTs. Composites consisting of different amounts of MWCNTs displayed an increase of the work of adhesion between the MWCNTs and the matrix, which improved both the tensile and impact strengths of the composites. The tensile and impact strengths of the MWCNT/epoxy composite improved by 59 and 562% with 0.3 phr of MWCNTs, respectively, compared to the epoxy composite without MWCNTs. Thermal stability of the 0.3 phr MWCNT/epoxy composite increased compared to other epoxy composites with MWCNTs. The enhancement of the mechanical and thermal properties of the MWCNT/epoxy nanocomposites is attributed to improved dispersibility and strong interfacial interaction between the MWCNTs and the epoxy in the composites prepared by VARTM.

• 한국농공학회지
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• 제25권2호
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• pp.67-75
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• 1983

The objectives of this paper were to measure the bond strengths of reinforced concrete in which the steel rods were coated with five different kinds of anticorrosion paints, and to compare their prevention effects in salt water. The paints used in the study were epoxy resin I . II . III, Z.R. P., and silicone resin, which were applied at rates recommended by the manufacturers. The bond strengths were measured on the 7-, 14-, and 28-th days after molding. Corrosion conditions of coated steel plate under fresh water, seawater, 10 % salt water, and 20% salt water, were inspected every month during four months test peoriods, respectively. The results obtained from tests are summarized as follows: 1. Paint-coating may reduce the bond strengths of reinforced concrete. Silicone resin paint showed some 20% reduction in the strength compared to those without the paint. However, the other paints seemed not to significantly affect the strength. 2. Picture analyses showed that epoxy resin I and II significantly prevented corrosion steel plates in seawater. Epoxy resin I and silicone resin coating did not do a good job in corrosion prevention. Z.R. P. paint was found to be moderate as preventive coating paint. 3. Varying soluble salt contents had little effects on the corrosion prevention of tested paints. 4. Epoxy resin I and II were found to be appropriate as a coating material to prevent the corrosion of steel rods in seawater. Z.R.P. may also be used for the purpose.

• Composites Research
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• 제31권6호
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• pp.293-298
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• 2018

본 논문에서는 항공기용 스트링거(Stringer)로 사용하기 위한 브레이드 복합재료(Braided composites)의 물성에 대해 연구하였다. 브레이드 프리폼(braid preform)을 $30^{\circ}$, $45^{\circ}$, $60^{\circ}$로 제작하기 위해 드럼 와인더 속도, 브레이드 속도, 멘드럴 직경과 같은 공정변수들을 정량화시켰고, 에폭시 수지 종류를 TGDDM, YD-128로 브레이드 프리폼에 다르게 적용하여 각도에 따른 브레이드 복합재료의 인장강도, 굽힘강도를 섬유부피분율에 따라 규명하였으며, TGA 분석으로 열적 특성과 에폭시 수지의 분해 온도를 조사하였다. 그 결과 브레이드 프리폼의 각도가 낮을수록 인장강도와 굽힘강도가 향상됨을 확인하였고, 분자량이 높은 에폭시 수지를 사용할 때 물리적 성질이 향상되었다.