Thermal and Flame Retardant Properties of Ethylene-Vinyl Acetate Copolymer/Modified Multiwalled Carbon Nanotube Composites

The synthesized flame retardant 9,10-dihydro-9-oxa-10-phosphaphanthrene-10-oxide/vinyl methyl dimethoxysilane (DV) was used to modify multiwalled carbon nanotubes (MWNTs). The results of FTIR, H-1-NMR, and TGA measurements show that DV has been covalently grafted onto the surfaces of MWNTs, and the MWNTs-g-DV is obtained successfully. Transmission electron microscopy images show that a core-shell nanostructure appears with MWNTs as the core and the DV thin layers as the shell, and the modified MWNTs with DV can achieve better dispersion than unmodified MWNTs in EVM matrix. Thermogravimetric analysis and cone calorimeter tests indicate that the thermal stability and flame retardant are improved for the presence of the MWNTs in EVM matrix. Moreover, the improvement is more evident for EVM/MWNTs-g-DV composite compared to unmodified MWNTs-based composite, which can be attributed to the better dispersion of the DV-modified MWNTs and to the chemical structure of the combustion residue. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 2974-2983, 2011