• Polymer(Korea)
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• v.26 no.5
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• pp.615-622
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• 2002

Weather-resistant coatings were prepared by mixing a synthesized mill-base and let-down silicone/acrylic resin in weight ratios of 4 : 6, 3 : 7, and 2 : 8. The weatherability of the prepared coatings was tested. The thermal stability, general physical properties, and weatherability of the films of the coatings were improved with silicone content. Among the three mixing ratios mentioned, the ratio of 2 : 8 was the most suitable for the preparation of weather-resistant Coatings. The coatings containing 30 wt% of silicone proved to be a high weather-resistant coating.

• Proceedings of the Korean Reliability Society Conference
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• 2002.06a
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• pp.115-115
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• 2002

최근 중장비용 도료의 외관 즉 색상 및 광택의 변화는 상품가치를 결정하는 중요한 요소의 하나로 대두되고 있다. 이와 관련 도장 품질향상을 위해서 각종의 신도료가 개발되고 있고 물성 확인은 필수적이다. 특히 검사 항목중 내후성 확인은 Field에서 2년 이상 장시간의 시험기간이 필요하나 검증기간 단축을 위해 시험실에서 Weathering test를 시행하고 있다. 그러나 이러한 Lab. test 결과와 실제 Field data와의 상관관계를 알 수 없어 추정에 그치는 것이 현실이었다. 본 연구에서는 중장비용 우레탄도료의 내후성에 영향을 미치는 인자를 고려, 물성을 대폭 향상시킨 도료에 대해 시험실 Weathering test 결과와 옥외폭로시험 결과, 실제 장비에 적용한 Data를 토대로 중장비용 우레탄 도료의 내후성시험 가속계수를 도출하여 개발도료의 내후성 검증기간을 단축하고자 하였다.

• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.722-730
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• 1994

The effects of antioxidant and carbon black on weatherability of crosslinked polythylene(XLPE) for electrical insulation were investigated. 16 compositions were prepared in other to determine the weathering resistance. Samples were exposed in xenon-arc lamp Weather-Ometer for 500, 1000, 1500, 2000 hours respectively. Tensile strength, elongation at break, dielectric strength and tan ${\delta}$ were measured to evaluate the weatherability of XLPE. The results indicated that the effect of carbon black was more prominent than antioxidant and synergistic effect, was observed when two additives were mixed.

• Polymer(Korea)
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• v.30 no.4
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• pp.350-356
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• 2006

In order to investigate the effect of the composition of weather-resistant coatings on physical properties, three different weather-resistant coatings were prepared by varying the ratio of a mill-base silicone/acrylic resin and let-down silicone/acrylic resin in weight ratios of 2 : 8, 3 : 7, and 4 : 6. The physical properties and weather-resistance of the prepared coatings were tested. It was found that the thermal stability, salt spray exposure, and weather-resistance were improved with increasing the amount of silicone. The optimum mixing ratio of mill-base silicone/acrylic resin to the let-down silicone/acrylic resin was 2 : 8. The coating containing silicone component of 30 wt% was found to be suitable as high weather-resistant coatings.

• Journal of Korean Society of Steel Construction
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• v.15 no.2
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• pp.147-157
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• 2003

The application in steel structures is increasing the mill sheet for the weathering steels by minimum maintenance cost in a life cycle cost. These have been collected and statistically analyzed to investigate chemical compositions, mechanical properties, weldability indices, weathering index and impact absorbed energy. From this study, although the band of dispersion in chernical compositions, mechanical properties and impact absorbed energy of the weathering steels appeared a little larger, the results revealed that these values have adequately satisfied the standard values of the Korean Standard. Furthermore, it was found that the weldability indices and the weathering index for the weathering steels have respectively satisfied the value prescribed by the Japanese Highway Specification and ASTM.

• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.497-510
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• 2018

In this study, the decay resistance of larch wood, which was heat treated by superheated steam, was evaluated by the field decay test. During the field decay test of 12 months, non-treated wood has been severely damaged by termite, however, no visible damage has occurred in the preservative-treated wood and superheated steam heat-treated wood. Results of field decay test showed approximately 5% mass loss of the non-treated wood and the preservative-treated wood, and approximately 1% mass loss of the superheated steam heat-treated wood. After the field decay test for 12 months, the residual amount of preservatives remaining in the preservative-treated wood was lower than that before the field decay test. It was considered that the preservative was partially eluted during the field decay test, and the mass loss of the preservative-treated wood was thought to be similar to that of the non-treated wood. Through this study and additional long-term monitoring test, superheated steam heat treatment can be considered to be an environmental-friendly method to enhance the decay resistance of wood against rot fungi and/or insect without chemical treatment such as preservative injection.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.265-269
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• 2001

nylon 6의 단점인 저온에서의 연성 및 내충격성 저하를 개선하는 동시에 nylon 6의 내후성도 개선시키는 방법의 하나로 유리전이온도가 매우 낮고, 내가수분해성, 내후성 및 연성(ductile property)이 뛰어난 불소함유 고분자계의 한 종류인 PVDF(polyvinylidene fluoride)를 nylon 6에 용융블렌드 하는 방법이 제안되었다. [1-5] (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.366-367
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• 2003

토목합성재료의 내후성은 사용되는 원료 물질, 기후조건, 하중조건, 노출 기간 등에 따라 상이한 결과를 나타내며, 이러한 영향인자에 대한 많은 연구가 국내외적으로 이루어졌으나 이는 각 적용지역의 환경조건을 고려하여 실시된 경우로 지역적인 조건과 기후 차이로 국내 여건에 적합한 데이터라 할 수 없다. 본 연구에서는 임시구조물로 적용된 분리형 보강토 옹벽의 전면체를 형성하는 부직포 지오텍 스타일에 대해 현장 적용 노출시험을 실시하였으며 약 1년 간의 지속적인 계측을 통해 실제 국내 현장에서 나타나는 부직포 지오텍스타일의 내후성 거동에 대해서 평가하였다. (중략)

• Journal of Conservation Science
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• v.17 s.17
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• pp.19-32
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• 2005

The exterior of Korean traditional wooden buildings have been painted with Danchung of painting method using glue and pigments. However because of losing traditional techniques and materials through the period of colonization and industrialization, many problems are occurring today. Especially after several years from painting, occurrence of scalings and flakings in painting layer is a serious problem. To improve weathering resistance of painting layer caused by stress from the difference of swelling and shrinkage between painting layer and wood plate, was examined by weathering tests. The stress is due to the hydrophilic property of wood, mechanical properties(tensile property and stress relaxation) of painting layer, and priming methods by various binders such as glue, acrylic emulsion(Primal AC-3444), acrylic resin(Paraloid B-72). Because stress relaxation of acrylic emulsion of which glasf transition temperature is below room temperature$(7^{\circ}C)$ is high, painting layers with acrylic emulsion generate no scalings and flakings and are in the most durable state in all weathering tests. Priming method which starts from low concentration to high concentration, is more effective to improve durability than other priming methods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2391-2400
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• 2015

Weather proof steels are used for steel bridges due to its high corrosion resistance under atmospheric conditions. However, instead of forming stabilized rust layers, general rust occurs on weather proof steels under high humidity condition close to seawater or shady places. In Japan, therefore, they perform rust stabilization treatment instead of unpainted treatment due to severe atmospheric conditions. However, most of domestic weather proof steels were constructed unpainted in the form of closed box-girder, which makes the periodical repetition of dry and wet hard to occur. For the steel bridges constructed on the Han river, the evaporation of water, dew condensation due to temperature change, and stagnant water due to rain affect harmfully on the formation of passive film on weather proof steels. Thus, in this research, in order to analyze corrosion properties inside the closed box-girder for the unpainted weather proof steel bridge in the waterworks safety zone, multiple ways of analysis such as observation with eyes, cellophane-tape test, steel thickness measurement, surface corrosion potential measurement, electron microscope analysis, and X-ray diffraction analysis of the rust were performed. As a result, unstable rust layer was observed inside the closed box-girder, and severe corrosion was observed on the top and bottom of the flanges due to the effects of stagnant water caused by rain, dew condensation, and de-icing materials.