# 산화그래핀이 폴리우레탄 폼 기계적 강도에 미치는 영향

• Kim, Jong-Min (Department of Naval Architecture and Ocean Engineering, Pusan National University) ;
• Kim, Jeong-Hyeon (Department of Naval Architecture and Ocean Engineering, Pusan National University) ;
• Choe, Young-Rak (Department of Naval Architecture and Ocean Engineering, Pusan National University) ;
• Park, Sung Kyun (Department of Physics, Pusan National University) ;
• Park, Kang Hyun (Department of Chemistry, Pusan National University) ;
• Lee, Jae-Myung (Department of Naval Architecture and Ocean Engineering, Pusan National University)
• Received : 2016.03.07
• Accepted : 2016.06.05
• Published : 2016.07.31
• 163 40

#### Abstract

In the present study, graphene oxide based polyurethane foams were manufactured as a part of the development process of mechanically strengthened polyurethane foam insulation material. This material is used in a liquefied natural gas carrier cargo containment system. The temperature of the containment system is $-163^{\circ}C$. First, graphene oxide was synthesized using the Hummers' method, and it was supplemented into polyol-isocyanate reagent by considering a different amount of graphene oxide weight percent. Then, a bulk form of graphene-oxide-polyurethane foam was manufactured. In order to investigate the cell stability of the graphene-oxide-polyurethane foam, its microstructural morphology was observed, and the effect of graphene oxide on microstructure of the polyurethane foam was investigated. In addition, the compressive strength of graphene-oxide-polyurethane foam was measured at ambient and cryogenic temperatures. The cryogenic tests were conducted in a cryogenic chamber equipped with universal testing machine to investigate mechanical and failure characteristics of the graphene-oxide-polyurethane foam. The results revealed that the additions of graphene oxide enhanced the mechanical characteristics of polyurethane foam. However, cell stability and mechanical strength of graphene-oxide-polyurethane foam decreased as the weight percent of graphene oxide was increased.

#### Acknowledgement

Supported by : 한국연구재단

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