Polymer Coated Multi-walled Carbon Nanotubes And The Effects On Of The Properties Of Epoxy Resin

The influences of polymer coated CNTs on the dispersion of CNTs in the epoxy matrix, and their effect on the mechanical properties, thermal performance of epoxy resin, have been studied with dynamic mechanical thermal analysis(DMA), thermal gravimetric analysis(TGA), thermal conductivity tester, scanning electron microscope(SEM). In addition, optical microscopy(OM) and scanning electron microscopy(SEM) were used to study the influences of polymer coated CNTs on the reaction induced phase separation(RIPS) of the epoxy resin(EP)/polyetherimide(PEI)blends.1、Carbon nanotubes(CNTs) functionalized by a nanothin poly(dopamine)(PDA)layer were produced by a one-pot, nondestructive approach, with direct polymerization of dopamine on the CNT surface. The thickness of the PDA layer can be well-controlled by the reaction time and the proportion of dopamine, and this thickness is found to be the key factor in controlling the dispersion of CNTs and the extent of the interfacial interactions between the CNT@PDA and epoxy resin. SEM results indicated that the dispersion of CNTs in epoxy was improved significantly by coating a nanothin PDA layer onto the CNT surface. In agreement with this finding,the CNTs funtionalized with the thinnest PDA layer(5 nm layer) provided the best mechanical and thermal properties. This result confirmed that a thinner PDA layer could provide optimized interfacial interactions between the CNT@PDA and epoxy matrix and weaken the self-agglomeration of CNTs, which led to an improved effective stress and heat transfer between the CNTs and polymer matrix.2、The effect of the CNT@PDA on the cloud points and the phase separation process of the EP/PEI blends were studied. The results show that the CNT@PDA might inhibit the phase separation process and enhance the phase separation temperatures of the EP/PEI system.3、Carbon nanotubes(CNTs) functionalized by a nanothin polyphosphazenes(PZS) layer was synthesized and the effect on the properties of epoxy resin was studied. The dispersion of CNTs in epoxy matrix could be improved by the PZS coating, while improving the mechanical properties, thermal properties of the epoxy resin nanocomposite. It might be explained that PZS coating can improve the crosslinking density and the curing degree of the epoxy resin.