Study On The Functionalization Of CNTs Via Plasma-induced Grafting And The CNTs/Epoxy Composites

Functionalized carbon nanotubes with good dispersion in thermosetting resin matrix,goodinterface compatibility and high interface bonding strength were prepared in a simple,economicaland environment-friendly way.The argon plasma method, argon plasma-assisted thermal initiationmethod, maleic anhydride (MAH) plasma induced-grafting polymerization method, MAH plasmaassisted terminal group modification method of CNTs functional methods and processingconditions were studied in this paper. We use the universal thermosetting epoxy resin as theresearch object,and prepared the functionalized carbon nanotubes/epoxy resin nanocompositematerials.Argon plasma activated CNTs, influence of the plasma processing parameters (Such as power,temperature, time, the chamber pressure, etc) on the a-CNTs microstructure, composition andstructure were examined. The dispersion of a-CNTs is better than the primitive CNTs in EP resin.A-CNTs/EP composite materials have excellent mechanics, heat, and other comprehensiveproperties. The method has characteristics of simple and easy, low carbon, good functionalizationeffect, can satisfy the requirements of the industrial production.Starting from the active a-CNTs, choose MAH of economy, easy to sublimate andvaporization as grafting monomer, get r-CNTs through the hot trigger polymerization of MAH inthe surface of the CNTs. Highly reactivity and good interfacial compatibility given by maleicanhydride film that formed on its surface, overcomed problems between CNTs surface inert andEP matrix compatibility to some extent, which improved the mechanic performance of EP curingcontent.Through argon plasma pretreatment and oxygen activation, formed peroxide on CNTs surfacefrom the primitive CNTs. After the functionalization of the grafting agent MAH plasma, its keyfracture to form free radicals which contains oxygen, thus lead to grafted polymerization of MAHin CNTs surface, get the m-CNTs that modified by PMAH film(One end of polymer chain fixedon the surface of CNTs as covalent bond, the other end can free extend).PMAH chain that graftingin M-CNTs surface not only gives it high reactivity and interface ability, but also can use its vastspace resistance to solve the serious problems since gathered and winded effectively,and realizethe good dispersion of m-CNTs in EP matrix, which improves the interface bonding strength.Thismethod has the characteristics of simple operation, no solvents intervention, high purity and highlyfunctionalizatoin, large-scale production, it is the important breakthrough of CNTs functiontechnology. The free extend of m-CNTs were modified by three ethylene four amine, prepared then-CNTs that surface modified with amino groups. Carboxy reacts with amino formed the firmamide key, it greatly enhanced the interface bonding strength of the n-CNTs and EP matrix,n-CNTs highly improved strong toughness of crosslinked epoxy resin,as well as excellent thermalstability. This technology has not reported in the literature and patent, which novelty andoriginality.