分散型石墨烯/奈米矽片複合材料於抗靜電應用

Abstract

此次實驗探討同為片狀結構之石墨烯與奈米矽片之交互作用以應用於抗靜電。兩種片徑與親疏水性不同之碳材來源被作為實驗比較。經由在水中混合與超聲波震盪後，發現片徑較大、本質上較為疏水之碳材能有效的被奈米矽片分散於水中。此外，經由穿透式電子顯微鏡(Transmission electron microscopy, TEM)觀察，在水中及油相中，石墨烯/奈米矽片複合材可形成水包油及油包水這種類似微胞結構型態。而後導入先前實驗室自製之分散劑POEM之變形，短鏈POEM，用於更深入探討分散機制、增加分散性以及增加分散液之長效穩定性。將製備好之分散液與水性聚氨酯做混參、塗佈與乾燥後，形成石墨烯/奈米矽片/水性聚氨酯複合膜。單純石墨烯/水性聚氨酯複合膜發現到大部分石墨烯皆沉降於薄膜底部，形成不均勻之複合膜。若導入奈米矽片，發現奈米矽片可提升石墨烯在水性聚氨酯中之分散性。從薄膜之電阻值可觀察到導入石墨烯/奈米矽片複合材於水性聚氨酯中，可將電阻值從10的12次方降低至10的7次方，且石墨烯在固定比例下可均勻分散在水性聚氨酯中，達到抗靜電之功能。

The interaction between the platelet-like materials of graphene and nano silicate platelet (NSP) was studied for antistatic applications. Two different source of graphite, electronic graphite and CPC graphite-like materials were compared for illustrating the dispersion mechanism involving the effect of the silicate platelet (NSP) presence. It was discovered that CPC graphite-like with the properties of oleophilic could be well dispersed in aqueous medium. Furthermore, the amphiphilic property and irreversibly dispersion behaviour either in water or in toluene, depending on the exposing order, were achieved for the graphene/NSP nanohybrid. The mechanism involved micelle-like microstructure of oil-in-water and water-in-oil forms. Low molecular weight of POEM (s-POEM), compared with home-made dispersant poly(oxyethylene)-segmented imide (POEM), was synthesized for affecting the dispersibility and long term stability of graphene. As prepared graphene/NSP nanohybrid was solution blending with WPU to form graphene/NSP/WPU nanocomposites film. The comparison among graphene/WPU, NSP/WPU and graphene/NSP/WPU was made. In the absence of NSP, graphene showed sedimentation in the bottom of composite film and resulted in the uneven performance of sheet resistance. The presence of NSP prevented graphene from sedimentation, leading to the Graphene/NSP/WPU nanocomposites, shown the sheet resistance from larger than 1012 of pristine WPU, to 107 ohm/sq with uniform electrical property in both side of film. These graphene/NSP/WPU composites can well meet the requirement of antistatic uses.