• 동력기계공학회지
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• 제18권5호
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• pp.106-114
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• 2014

For the purpose of development of polyurethane sealing material, polyurethane resins reinforced with CuO were prepared from polyol and MOAC(4,4'-Methylenebis(2-chlorobenzeneamine)). And the effects of compositions on the mechanical properties of the reinforced polyurethane resin were experimentally examined. The polyurethane resin got to be thermally decomposed at $260^{\circ}C$ and completely carbonized around $500^{\circ}C$. Tensile strength, elongation and hardness of the polyurethane resin increased with the content of MOCA. CuO was uniformly dispersed in the polyurethane resin by 1 minute's ultrasonic radiation. Tensile strength, elongation and hardness of the polyurethane resin reinforced with CuO increased with the content of CuO. Tensile strength and hardness of the reinforced polyurethane resin increased with particle size of the CuO, but elongation decreased. CuO showed higher tensile strength and hardness than any other additives, and lowest elongation.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.345-351
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• 2007

The research which it sees will confront to the coating with paint material and a coating with paint public law application of the river bridge and it will present it will sleep and it will execute, it will reach and a comparison - an analysis from the research which it tries to respect middle of special environment the polyurethane system which is a method coating with paint system and fluorine resin system, against a ceramic system it executed more an objectivity and rational fundamental data. With research method against each coating with paint evening sunlight a research investigation material and structure, it separated with spatial-temporal characteristic and economic viewpoint it executed. When considering overview from material viewpoint, fluorine resin system ceramic system polyurethane system pure with it is judged with the fact that it is excellent. There is a possibility of saying that the coefficient of friction of the fluorine resin system which uses the weapon quality zinc end coating compound ever so hard and polyurethane system is excellent ceramic system than from structure viewpoint. That fluorine resin system = polyurethane system ceramic system pure with it is excellent, it is judged from spatial-temporal characteristic viewpoint. It measures but it considered an internal troubles year grudge in the standard which becomes disturbance the place where it executes the market the expectation life person of the general bridge against 100 years the result fluorine resin system polyurethane system ceramic system which compares a materials unit cost pure with it appeared.

• 한국염색가공학회지
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• 제28권1호
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• pp.40-47
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• 2016

As a coating material for loudspeaker dampers, resilient polyurethane/epoxy hybrid resins were synthesized to replace conventional phenol resin and examined the physical properties, which are not only environmentally friendly but also not harmful to human. Five types of polyurethane resins were synthesized in the step-shot method using methylene diisocyanate, three polyols such as poly tetramethylene ether glycol(PTMEG, MW:2000), poly(1,4-buthylene adipate(PBAP, MW:2000), and poly carbonatediol(PCD, MW:2000), and three chain extenders such as ethylene glycol(EG), neopentyl glycol(NPG), and 1,4-buthandiol(1,4-BD). The five types of synthesized polyurethane resins and commercially available bisphenol A type epoxy resin were blended in weight ratios of 90:10, 70:30, and 50:50 to synthesize 15 types of polyurethane/epoxy hybrid resins. Among the polyurethane resins, the one that was synthesized using PCD and 1,4-BD showed excellent tensile strength, 100% modulus, low extension, and relatively high viscosity. Polyurethane/epoxy hybrid resins with higher epoxy resin contents showed better thermal properties and water resistance while those with higher polyurethane contents showed higher flexibility. The polyurethane/epoxy hybrid resin made by blending the polyurethane based on PCD and 1,4-BD with a bisphenol A type epoxy resin in a weight ratio of 70:30 was identified to be the most suitable to be used in speaker dampers.

• 대한치과기공학회지
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• 제34권3호
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• pp.227-235
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• 2012

Purpose: This study compared the surface hardness (Vickers) and microstructural characteristics between a type IV stone with and without die hardening treatment, a polyurethane die material. Methods: Materials used were a type IV stone(MG Crystal Rock), two die hardeners (Hardening bath, Epox-it), and a polyurethane resin material(Polyluck). Six specimens per group were prepared according to manufacturer's directions. The prepared specimens were tested by means of hardness test, one-way ANOVA analysis, scanning electron microscopic(SEM) observations and energy dispersive spectroscopic(EDS) analysis. Results: In the hardness test and its statistical analysis, there was no significant difference in the surface hardness between a type IV stone and type IV stone with die hardener coating, type IV stone mixed with an epoxy like material instead of water. In contrast, polyurethane resin material exhibited significantly greater surface hardness than other specimen groups (p<0.05). Conclusion: By considering the results of the hardness test, SEM observations and EDS analysis, although the die hardeners on type IV stone did not show remarkable improvement in surface hardness, the die hardener coating on the surface of type IV stone material did show decrease of microporous and improvement of surface defects.

• 한국염색가공학회지
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• 제29권1호
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• pp.25-36
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• 2017

This study worked on the synthesis of waterborne polyurethane/epoxy hybrid resins containing aminosilane compound to replace conventional phenol resins used for a coating material for loudspeaker dampers, which are not harmful to human being. Waterborne polyurethane resins were synthesized from two diisocyanate of 4,4'-diphenylethane diisocyanate and toluene diisocyanate, two polyols of polyester polyols(PEP), polycarbonatediol(PCD), including and anionic center of dimethylol butanoic acid, a chain extenders of ethylenediamine(EDA), and a neutral agent of triethylamine. Synthesized polyurethane resins and commercially available bisphenol A type waterborne epoxy resin were blended in weight ratios of 80:20 to prepare polyurethane/epoxy hybrid resins. The synthesized waterborne polyurethane/epoxy hybrid resins were reacted with aminosilane compound to improve mechanical properties. Aminosilane-treated polyurethane /epoxy hybrid resins showed better mechanical properties.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.498-500
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• 1999

Polyacetals with melamine were investigated in terms of mechanical properties. It was found that tensile strength, impact strength and elongation were decreased with the increase of melamine content up to 30 par, flexural strength had no remarkable changes. For master-batch using polyurethane as carrier resin, in which the ratio of polyurethane to melamine was 2:1, tensile strength and flexural strength were decreased and impact strength remained unchanged with melamine me content.

• 한국응용과학기술학회지
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• 제36권4호
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• pp.1358-1364
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• 2019

스테인레스 스틸에 대한 합성된 폴리우레탄-에폭시 수지의 기계적 특성은 SEM, FT-IR, 인장특성, 그리고 EIS에 의한 특정질량손실량, 입도분석 등에 의해 물성을 측정하였다. 친환경적인 중방식 도료에 관한 관심이 고조됨에 따라 스테인레스 등의 금속에 코팅하는 무용제 도료를 합성하였다. 폴리올, IPDI, 충진제, 실리콘 계면활성제, 촉매 등이 함유된 기존 중방식수지보다 폴리올, MDI, 충진제, 실리콘 계면활성제, 촉매가 함유되어 합성된 중방식수지의 도료가 온도변화에 따른 인장강도가 증가하였고, 전해성이 높은 용액 속에서 저헝력이 크게 측정되었으며, 내구력과 강도가 양호하였다. 견고한 중방식수지의 기계적 특성은 가교와 부식환경의 차단력이 증가함에 따라 강도가 증가하였다. 결론적으로 중방식의 가교된 미세조직은 방청코팅이 어려운 스테인레스 스틸 같은 금속물질 코팅에도 좋은 실험결과를 보여주었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.38-43
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• 2001

The interfacial adhesive joining characteristics of the foams are very important for the structural integrity of sandwich structures. Peel strength is one of the best criteria for the interfacial characteristics of the sandwich structures and peel energy is most commonly used for the interfacial characteristics. The peel strength is the first peak force per unit width of bond line required to produce progressive separation by the wedge or other crack opening type action of two adherends where one or both undergo significant bending and the peel energy is the surface active energy per unit width of bond line. In this work, to investigate the strengthening effect of resin treatment on the interfacial surface of foam material, peel strength and peel energy of epoxy resin treated polyurethane foam core sandwich structures were obtained by the cleavage peel tests and compared with those of non surface treated polyurethane foam core sandwich structures.

• Journal of the Korean Wood Science and Technology
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• 제51권1호
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• pp.14-22
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• 2023

Economical use of larix (larch) boards (grade 3) in industries is lower than that of imported hardwood; thus, studies have been conducted toward performance improvement of larix boards. Herein, flexural modulus of larix board samples laminated with wood adhesives polyurethane resins, poly (vinyl acetate) resins, phenol-resorcinol-formaldehyde resins, melamine-formaldehyde resins, and urea-formaldehyde resins was compared with that of the samples bonded with adhesives reinforced with mesh-type basalt fibers. Moreover, the flexural moduli of the laminated samples bonded by mesh-type basalt fibers were compared with those of reinforced samples. The results showed that boards laminated with polyurethane and urea-formaldehyde resin adhesives had higher flexural modulus than those without the lamination. In particular, the increase in the flexural modulus was relatively significant for the 2- and 3-ply board structures laminated with polyurethane adhesives compared to those with reinforcement. The 3-ply board structure without reinforcement had the highest flexural modulus when the urea-formaldehyde resin adhesive was used.

• 공업화학
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• 제17권4호
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• pp.381-385
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• 2006

에멀젼 입자 표면의 새로운 형태학적 분석을 위하여 원자간력 현미경을 이용한 위상지연 가시화법을 응용하여 폴리우레탄 수지와 아크릴레이트 수지로 구성된 폴리우레탄 아크릴레이트 하이브리드 에멀젼의 형태 및 물성 연구를 시도하였다. 데이터의 분석을 위하여 순수한 수분산 폴리우레탄과 아크릴레이트 에멀젼 입자를 각각 합성하였고, 유사한 형태로 합성된 두 입자에 대한 각각의 서로 다른 위상지연의 크기를 얻을 수 있었다. 이들 데이터를 기준으로 수십 나노미터의 분해능으로 폴리우레탄 속에 혼성된 아크릴 수지의 입자표면을 구별하고 특성을 분석하였다. 따라서 위상지연 가시화법의 응용으로 서로 다른 2가지 화합물의 특성을 구분하고 이를 가시화 할 수 있는 새로운 가능성을 제시하였고, 이러한 분석법은 유기 합성 고분자의 입자 표면분석 및 물성연구에 유용함을 기술하였다.