取向碳纳米管膜/氰基树脂复合材料的制备与性能强化机制

以浮动催化化学气相沉积法(FCCVD)碳纳米管(CNT)膜为原料,通过氰基树脂溶液浸渍法制备CNT预浸膜,然后采用热辅助牵伸和热压固化的方法制备高取向CNT膜复合材料。详细分析了热处理的温度和树脂溶液浓度对CNT预浸膜拉伸性能的影响,从而得到合适的热辅助牵伸工艺,并考察固化工艺对复合材料性能的影响。在此基础上,从浸润特性、CNT取向程度和层间剪切性能方面揭示CNT膜复合材料力学性能的强化机制。结果表明与传统CNT膜牵伸工艺相比,CNT预浸膜热牵伸工艺更有利于制备高取向CNT膜复合材料。热牵伸的温度和树脂溶液的浓度是制备高取向、低孔隙CNT预浸膜的关键因素。通过固化工艺的改变可有效调控氰基树脂的反应程度碳纳米管薄膜/氰基树脂复合材料的拉伸性能。经高温后固化处理后,CNT膜/氰基树脂复合材料的拉伸强度和模量分别高达2 748 MPa和302GPa。优异的树脂浸润特性、层间剪切强度以及高的CNT取向度使CNT膜复合材料中CNT更有利于协同承载,从而提高其力学性能。

Fabrication and strengthen mechanisms of aligned carbon nanotube sheet/cyano resin composites

The CNT sheet prepregs were fabricated by cyano resin solution impregnating continuous carbon nano-tube (CNT)sheet,which was prepared by floating catalyst chemical vapor deposition grown (FCCVD)method.A well aligned CNT sheet composite was fabricated by subsequent hot-stretching treatment and hot pressing process. The effects of hot-stretching temperature and resin solution concentration on the tensile properties of the CNT prepregs were analyzed and the hot-stretching process was optimized.The effect of curing cycle on the tensile prop-erties of CNT sheet reinforced cyano resin matrix composite was studied.Through analyzing the wetting characteris-tics,CNT alignment and interlaminar shear strength,the strengthen mechanisms of CNT sheet reinforced cyano resin matrix composites were revealed.The results indicate that the CNT sheet prepreg hot stretching process is more beneficial for getting highly aligned CNTs within the CNT sheet reinforced cyano resin matrix composite than the traditional CNT sheet stretching process.The temperature and resin solution concentration are the key factors to prepare high property cyano resin impregnated CNT film,which has high CNT orientation and low porosity. Through changing the curing cycle,the extent of reaction of cyano resin and the tensile properties of the CNT sheet/cyano resin composite are improved.The tensile strength and modulus of the CNT sheet/cyano resin composite reach up to 2748 MPa and 302 GPa after postprocessing.Benefited from the superior wetting property,the high in-terlaminar shear strength and the high alignment degree of CNTs,the CNT sheet/cyano resin composite shows high tensile properties,due to efficient load bearing inside the CNT network.