Study On Dispersion Of Carbon Nanotubes In Epoxy Resin And Performance Of Composites

Ever since the carbon nanotubes (CNTs) were found, they have been admired for its excellent mechanical property, electronic property and heat transfer ability. They have been applied in the modification of polymer including epoxy resin (EP). However, CNTs agglomerate easily and have chemical inertia. The poor dispersibility of CNTs become one of main obstacle for its broad application in the polymer matrix. Therefore modification to CNTs become one of effective ways to improve its dispersibility.In this paper, we mainly studied the dispersion of CNTs in solvent and in epoxy matrix, except that we also did some further researches on the mechanical and rheological properties of composite. Firstly, multi-walled carbon nanotubes (MWNTs) were modificated by an acidic solution and several kinds of surfactant, through investigating modificated CNTs by FT-IR, XRD, SEM and TEM, we found that their dispersive capability had been greatly improved, the dispersing performance from high to low is as follows:CNTs with surfactant modification>CNTs with acidification treatment>raw CNTs. Secondly, considering the factors of the ultrasound dispersion and surfactant dispersion, the effects of each factors on dispersibility of CNTs in solvent and EP matrix have been studied. The dispersion stability of MWNTs suspension and TEM analysis indicate that at the best ultrasonic conditions, CNTs were dispersed well with the BYK-9077in EP matrix while CNTs with the SDS or CTAB were dispersed well in solvent. Furthermore, MWNTs/EP composites were made by blending in solution. Then the mechanical and rheological properties of the composite were studied according to SEM and TEM images, and then the effects of such factors as before and after modification of MWNTs, different amounts of MWNTs, and different amounts of surfactant on properties of the composites were surveyed. The results show that adding of MWNTs, especially the modified MWNTs, help to improve the mechanical properties of the composites. The characterization of rheological properties showed indirectly that the modified MWNTs disperse evenly in EP matrix.