Morphological, electrical, electromagnetic interference (EMI) shielding, and tribological properties of functionalized multi-walled carbon nanotube/poly methyl methacrylate (PMMA) composites

The functionalized multi-walled carbon nanotubes (MWCNTs) had been prepared via Friedel-Crafts acylation with maleic anhydride. X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA) confirmed the functionalization of MWCNTs. The composites with maleic anhydride modified MWCNTs (Mah-g-MWCNTs) and poly (methyl methacrylate) were then prepared by the in situ and ex situ solution polymerization system. The Electromagnetic Interference (EMI) shielding effectiveness (SE) of Mah-g-MWCNTs/PMMA composites increased with the increasing of the Mah-g-MWCNTs content, and the in situ system shows higher EMI SE value. The wear resistance was enhanced while the loading of the Mah-g-MWCNTs was above the percolation threshold, and the in situ system provides higher efficiency than that of ex situ system. (C) 2009 Published by Elsevier Ltd.