碳纳米管的偶联剂修饰及其在环氧树脂复合材料中的应用

为了在环氧树脂( EP) 复合材料中改善碳纳米管(CNTs) 的分散性和获得优良的界面特性, 利用Fenton 试剂对CNTs 进行了羟基化处理, 然后分别利用硅烷偶联剂KH550、KH560、KH570 和钛酸酯偶联剂NDZ201对羟基化CNTs 进行表面修饰, 通过SEM、TGA、DSC 和阻抗分析仪研究偶联剂修饰对CNTs/ EP 复合材料性能的影响。实验结果表明: Fenton 试剂和4 种偶联剂修饰都能显著改善CNTs 在复合材料中的分散性, 提高EP的玻璃化温度(T_g) 和热稳定性, 其中偶联剂修饰比Fenton 试剂处理更有效; 然而这些改性却大幅度降低了复合材料的导电性能、介电常数以及介电损耗。4 种偶联剂中, KH560 对应的复合材料的T_g最高, 热稳定性和导电性能最好, 同时具有较高的介电常数和较低的介电损耗。 

Coupling agent modification of carbon nanotubes and their applications for epoxy resin composites

To obtain good dispersion and interface characteristics in epoxy resin ( EP) composites, carbon nanotubes (CNTs) were firstly hydroxylated with Fenton reagent treatment, and then surface-modified with silane coupling agent KH550, KH560, KH570 and titanate coupling agent NDZ2201, respectively. The influence of coupling agent modification on the properties of CNTs/EP composites was investigated by SEM, DSC, TGA and impedance analyzer. The experimental results show that Fenton reagent treatment and modification using four kinds of coupling agents can all obviously improve the dispersion of CNTs, glass transition temperature (Tg) and thermal stability of EP. All coupling agent modifications are more effective than the Fenton reagent treatment. However, these modifications can significantly reduce the electric conductivity, permittivity and dielectric loss of the composites. Among the four kinds of coupling agent modification, the composite modified by KH560 shows the highest Tg, the best thermal stability and electric conductivity, high permittivity and low dielectric loss.