采用树脂传递模塑(Resin Transfer Molding, RTM)工艺制备碳纳米管(Carbon Nanotubes, CNTs)/玻璃纤维/环氧混杂多尺度复合材料, 研究其结构与电性能的相关性。采用优化的分散工艺将CNTs分散于环氧树脂中制成纳米复合树脂基体, 经RTM工艺制备玻璃纤维/碳纳米管混杂多尺度复合材料, 考察CNTs形态结构变化和复合材料的导电行为。研究表明, RTM复合材料的电渗流阈值为0.3 wt%, 而使用非离子表面活性剂Triton X-100作为分散助剂的复合材料电渗流阈值为0.1 wt%。当CNTs含量为0.3 wt%时, RTM模具入口处复合材料电阻率比中间和出口处低2个数量级。TEM分析表明, CNTs动态渗流网络形成以及CNTs在复合材料内部的分布是导致RTM复合材料电性能呈现梯度变化的原因。
Carbon Nanotubes (CNTs)/glass fabric hybrid multi-scale composites was fabricated via Resin Transfer Molding(RTM)technique to explore the relationship of its structure and electrical properties. CNTs was dispersed in epoxy resin to gain a nano-composite matrix used for RTM process. The resulting hybrid multi-scale composites were studied with respect to the structural changes and electrical properties. The research shows that the hybrid composites with and without surfactant, Triton X-100, bear the percolation thresholds of 0.1 wt% and 0.3 wt%, respectively. At CNTs content of 0.3 wt%, the specimens taken from the inlet gate region of the RTM equipment show a decrease of electrical volume resistivity by two magnitudes compared with those of the samples taken from the middle and outlet gate region. The analysis of Transmission Electron Microscopy (TEM) indicates that the variation in the network structure of the CNTs within the nano-composite matrix during the injection molding process is responsible for the gradient in resistivity of the RTMed laminates.
[1]Sandler J, KirK J.Ultra-low electrical percolation threshold in carbon-nanotube-epoxy composites[J].Polymer, 2003, 44(19):5893-5899.
[2]Indra Vir Singh, Masataka Tanaka.Effect of interface on the thermal conductivity of carbon nanotube composites[J].International Journal of Thermal Sciences, 2007, 46(9):842-847.
[3]Eitan A, Fisher F, Andrews R, et al.Reinforcement mechanisms in MWCNT-filled polycarbonate[J].Composites Science and Technology, 2006, 66(9):1162-1173.
[4]邓杰.高性能复合材料树脂传递膜技术(RTM)研究[J].纤维复合材料, 2005, 22(1):50-53.
[5]Chen G X, Li Y J.Ultrahigh-shear processing for the preparation of polymer/carbon nanotube composites[J].Carbon, 2007, 45(12):2334-2340.
[6]Hao X Y, Gai G S.Development of the conductive polymermatrix composite with low concentration of the conductive filler[J].Materials Chemistry and Physics, 2008, 109(1):15-19.
[7]Kota A K, Cipriano B H.Electrical and rheological percolation in polystyrene/MWCNT nanocomposites[J].Macromolecules, 2007, 40(20):7400-7406.
[8]Shaffer M S P, Fan X, Windle A H, et al.Dispersion and packing of carbon nanotubes[J].Carbon, 1998, 36(11):1603-1612.
[9]江琳沁, 高濂.化学处理对碳纳米管分散性能的影响.无机材料学报[J].2003, 18(5):1135-1138.
[10]Elisabete F, Reia da Costa.RTM processing and electrical performance of carbon nanotube modified epoxy/fibre composites[J].Composites(Part A), 2012, 43(4):593-602.
