本論文探討以奈米分散技術製備氧化石墨烯混成材料，將氧化石墨烯混入聚氨酯(Polyurethane, PU)中，製備具阻氣能力之薄膜。研究以分散碳材為主軸，從第四章開始首先探討高分子型分散劑對不同氧化數之氧化石墨烯進行分散，並添加自行合成之聚乙基醚段鏈與異氰酸鹽衍生之高分子型界面活性劑(Poly(oxyethylene)-segmented urea, POEU)，控制氧化石墨烯與分散劑之不同比例下(1：1、1：10及1：20)，此POEU為非離子型親水/親油界面活性劑，從分子結構的觀點，苯環結構式存在於高分子型界面活性劑中，提供高分子界面活性劑與氧化石墨烯於界面上，促成π-π電子的影響，且構造上包含Urea的官能基，則Urea上之hydrogen bonding可使氧化石墨烯分子呈現可控制性分子級分散效應。最後將POEU/氧化石墨烯奈米混成物均勻分散於油性PU當中，控制氧化石墨烯不同氧化數含量(0%、4%、40%)以不同比例(0.5wt%、1wt%及3wt%)分散於PU高分子基材中，並比較不同片徑之石墨烯對阻氣能力之影響。由於氧化石墨烯本身的立體結構與高長寬比等特性，能在PU中形成立體結構障礙，作為阻擋氣體通過的路障，製作出具高阻氣能力的PU/氧化石墨烯複合薄膜，且機械性能上展現出極佳的效應。

Because of graphene oxide mechanical, and thermal properties, it is being explored for various applications and has attracted enormous academic and industrial interest. In this study, the preparation of polyurethane (PU) nanocomposites with graphene oxide (GO) using a simple solution dispersion processing method with surfactant poly(oxyethylene)-segmented urea (POEU). Well-dispersed graphene oxide/PU nanocomposties have good gas barrier properties, mechanical properties and thermal properties. The gas barrier properties of the graphene oxide-based nanocomposite with molecule-level dispersion are significantly improved. Graphene layers in the polymer matrix are capable of producing a tortuous path, which acts as a barrier for gases. A high tortuosity leads to superior barrier properties and lower permeability of PU. PU/GO have a 44.31% increase in gas barrier properties. Furthermore, a 507% increase in tensile strength and a 96.26% improvement of toughness and a 19.75% increase of water contact angle and a 14.5% increase of degradation temperature are achieved by addition of 3wt% of GO 4% which oxygen content is 4%. The improved properties of the composite film could lead to potential applications in food package.

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