• Elastomers and Composites
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• 제48권3호
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• pp.241-248
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• 2013

polyester형 polyurethane foam은 낮은 내가수분해성을 가지므로 quasi prepolymer법에 의한 acrylic polyol을 사용함으로써 극복될 수 있다. acrylic polyol을 함유한 polyurethane foam은 acrylic polyol 함량이 증가함에 따라 인장강도와 경도가 증가하였다. 하지만 split 인열강도와 인열강도는 약간씩 변화되었다. polyurethane foam의 내가수분해성은 인장강도의 손실 백분율로 측정하였으며 acrylic polyol 함량이 25.5g에서 102g으로 증가함에 따라 향상되었다.

• 한국안전학회지
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• 제25권1호
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• pp.38-43
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• 2010

The smoke density and noxious gas for phenol foam and polyurethane foam were measured according to test methods in ASTM E 662 and KS F 2271. It was observed that phenol foam had the possibility of application for sandwich panel and board compared with polyurethane foam. In the experimental results, phenol foam showed comparatively excellent property than polyurethane foam in smoke density and noxious gas. The polyurethane foam showed comparatively high smoke density and didn't meet the evaluation standard of noxious gas in KS F 2271. From the experimental results of smoke density and noxious gas, it can be said that phenol foam has both comparatively good safety and high possibility of application than polyurethane foam in the building fire of sandwich panel structure because of lower smoke density and noxious gas.

• 대한기계학회논문집A
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• 제24권12호
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• pp.3018-3025
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• 2000

It is possible to shorten developing process by making model using polyurethane foam in the area of automobile development process, etc. However, this skill is too difficult to be of practical use because machining is not easy due to characteristic of polyurethane foam. Domestic and foreign automobile company use clay, polyurethane foam. etc,, those are easy to handle and to make model after completing design sketch. But these materials is difficult to the machined and be worked by humans hand, There are so many difficult problem for machining by making model using polyurethane foam since cutting of elastic body like polyurethan foam has never been studied. Therefore, in this study, it is investigated to measured cutting force that is generated in case of polyurethane foam machining, and to make systematize tool compensation of polyurethane foam cutting work on automobile model by modification of tool offset method on existing steel.

• KSBB Journal
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• 제7권3호
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• pp.172-178
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• 1992

담체로 사용된 polyurethane foam은 Rizopus chinensis의 균사가 부착하여 안정하게 증식할 수 있게 하였다. 고정화를 위해 사용된 네 종류의 polyurethane foam중 GP-160이 고정하ㅗ 매체로 우수한 성질을 보였고, 입자의 크기는 7-8mm가 적당하였다. Rizopus chinensis의 현탁 배양과 polyurethane foam에서의 고정화 배양을 비교할 때, 전체 리파아제의 활성도는 큰 변화가 없었지만, 고정화 배양의 경우 extracellualar lipase의 생성을 억제하여 intracellular lipase의 활성도를 현탁 배양의 경우보다 약 2배가량 높일 수가 있었다. 고정화 세포의 열안정성을 조사하기 위하여 35~$50^{\circ}C$사이에서 열에의한 비활성화 에너지값을 구해본 결과, 그 값이 28.7kcal/mol로서 본 연구에서 제조된 고정화 세포의 생촉매가 배교적 좋은 열안정성을 갖고 있다.

• 대한의용생체공학회:의공학회지
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• 제19권3호
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• pp.215-224
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• 1998

본 논문은 급성 간 부전 환자나 간이식 대기상태에 있는 환자에 이용하기 위한 체외 간 보조장치를 개발하기 위한 기초 실험에 관한 것이다. 밀도 33kg/m, 평균 직경 500um, 60-70%의 window를 가진 폴리우레탄 폼을 15% NCO-프리폴리머로 제조하였다. 폴리우레탄 폼에 접종된 간세포는 3일 후에 거의 모두 100-150um 크기의 구상체를 형성하였다. BSA 코팅을 한 폴리우레탄 폼은 BSA로 코팅하지 않은 폴리우레탄 폼보다 간세포 구상체 형성 시간이 더 짧았다. 폴리우레탄 폼에 형성된 간세포 구상체의 간 기능을 증명하기 위하여 암모니아 제거율과 요소 및 알부민 분비율을 측정하였다. 폴리우레탄 폼은 간세포 구상체 배양에 적합하며, 폴리우레탄 폼 내에서의 간세포 구상체 배양은 체외 간 보조장치로의 개발 가능성이 높다.

• 한국결정성장학회지
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• 제26권5호
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• pp.209-214
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• 2016

Foam reaction injection molding (FRIM) is a widely used process for manufacturing polyurethane foam with complex shapes. Numerical model for polyurethane foam forming reaction during FRIM process has been intensively investigated by a number of researchers to precisely predict final shapes of polyurethane foams. In this study, we have identified a problem related with a previous theoretical model for polyurethane foam forming reaction. Thus, previous theoretical model was modified based on experimental and computational results.

• 한국화재소방학회논문지
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• 제34권2호
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• pp.7-13
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• 2020

경질 폴리우레탄(Polyurethane) 폼(Foam)의 난연 성능을 개선하기 위하여 외부에 물유리를 코팅하였다. 무기질인 물유리 코팅층이 적용된 우레탄폼의 콘칼로리메터의 열방출율(Heat release rate)은 급격히 감소하였다. 폴리우레탄 표면에 코팅된 물유리는 화염에 노출되었거나 가열되었을 때 유리화 반응과 미 탈출 수분에 의한 발포현상으로 인해 유리질 폼을 형성하게 된다. 폴리우레탄 폼 위에 형성된 유리질 폼은 단열층이 되어 10 min 이상 폴리우레탄 폼의 연소를 억제하였다. 이러한 결과에 따라서 물유리는 경질 폴리우레탄 폼의 난연 특성을 개선할 수 있음을 확인하였다.

• 한국안전학회지
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• 제32권1호
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• pp.108-114
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• 2017

According to an increase in demand for polyurethane soft foam for thermally insulated containers, the purpose of this study is based on redefining existing rigid polyurethane foam insulation KS standard which has been limited to building material-based authentication techniques. Since there are arising concerns of consumer rights and safety due to humidifier fungicides and urethane track incidents, there are elements to be further researched on rigid polyurethane foam insulation for refregerated containers. Thus, we reviewed the prior standards for rigid polyurethane foam insulation and verified the validity of certification testing method for the new standard with self-foamed polyurethane.

• 한국산업보건학회지
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• 제23권2호
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• pp.57-64
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• 2013

Objectives: Skin exposure to diisocyanates may be an important risk factor for respiratory sensitization to leading asthma. However little is known about the extent of worker's diisocyanates skin exposure and the effectiveness of personal protective equipments in polyurethane foam manufacturing companies. This study provides data on diisocyanates skin exposure, surface diisiocyantes contamination of foams and the effectiveness of personal protective gloves in five polyurethane foam manufacturing companies. Materials and methods Colorimetric SWYPE pads are used for the determination of diisocyanates on surfaces of workers skin and polyurethanes foams. Results: The forearms, necks and faces of workers in polyurethane foam manufacturing companies were found to be contaminated with diisocyanates. Heavy contamination with uncured diisocyanates at large block foams surfaces were found. Personal gloves of workers for skin protection showed significant penetrations by diisocyanates. Conclusions: We found that all workers in polyurethane foam manufacturing companies could be exposed to diisocyanates by skin exposure. Also further researches which would better quantify skin exposure are needed.

• 대한조선학회논문집
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• 제56권4호
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• pp.291-297
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• 2019

Polyurethane foam is the most efficient, high-performance insulation material, used for liquefied natural gas carrier (LNGC) insulation. Because LNGC is exposed to sloshing impact load due to ship motion of 6 degrees of freedom, polyurethane foam should be sufficient dynamic properties. The dynamic properties of these polyurethane foam depends on temperature and density. Therefore, this study investigates the dynamic response of polyurethane foam for various temperature($25^{\circ}C$, $-70^{\circ}C$, $-163^{\circ}C$) and density($90kg/m^3$, $113kg/m^3$, $134kg/m^3$, $150kg/m^3$) under drop impact test with impact energy of 20J, 50J, and 80J. For dynamic response was evaluated in terms of peak force, peak displacement, absorb energy, and the mechanical property with minimized density effects. The results show the effect of temperature and density on the polyurethane foam material for the dynamic response.