Preparation of acrylic/MWNTs nanocomposite latexes via ultrasonically-assisted emulsion polymerization: A comparative study

In this study, an efficient method has been presented for preparation of uniform dispersion of modified multiwall carbon nanotubes (G-MWNTs) in poly (methyl methacrylate-co-butyl acrylate) via ultrasonically-assisted emulsion polymerization. Two steps were exploited for this reason: first, MWNTs were modified via Friedel-Crafts acylation and polymerizable functional groups were incorporated to their surfaces and second, an optimized ultrasonically-assisted emulsion polymerization was applied to reach to the desired nanocomposites. The progress of modification reaction was followed by FT-IR and TGA analyses and morphology of the obtained latexes were observed by TEM. Studies on the final properties revealed that the inclusion of G-MWNTs in the acrylic copolymer has significant enhancement in thermo-mechanical properties of the resulting films. Thermal conductivity of the samples increased remarkably as a function of MWNTs content. It was found that at 3 wt% of G-MWNTs, thermal stability increased more than 29% and tensile strength and Young modulus of the resulting films were improved up to 70% and 75%, respectively. To elucidate the importance of this technique, similar nanocomposite latexes were prepared by simple mixing and compared with the above obtained results. (C) 2015 Elsevier Ltd. All rights reserved.