Multiwalled carbon nanotubes functionalized with 7-octenyltriclorosilane and n-octyltrichlorosilane: dispersion in Sylgard®184 silicone and Young modulus

• Published in: Journal of materials science 2009, Vol.44 (13), p.3476-3482
• Main Authors: Vast, L., Carpentier, L., Lallemand, F., Colomer, Jean-Francois, Tendeloo, G.V., Fonseca, A., B.Nagy, J., Delhalle, J.
• Format: Article
• Language: English
• Subjects: Chemical Sciences
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-009-3464-1

Sylgard®184/multiwalled carbon nanotube (MWNT) composites have been prepared by in situ polymerization using purified and functionalized multiwalled carbon nanotubes (f-MWNTs) as fillers. Surface modification of the MWNTs has been carried out by silanization with 7-octenyltrichlorosilane (7OTCS) and n-octyltrichlorosilane (nOTCS). The modification and dispersion of the carbon nanotubes in composites were characterized by X-ray photoelectron spectroscopy (XPS), transmission electron spectroscopy (TEM), and high-resolution transmission electron spectroscopy (HRTEM). Young’s modulus results were derived from indentation testing. It is shown that the terminal-vinyl group of 7OTCS molecules plays an essential role for both the dispersion of the f-MWNTs in the composite and its mechanical properties. At loading as low as 0.2 wt%, the Young’s modulus is shown to increase up to 50%. This is interpreted as resulting from a combination of the good compatibility in the forming silicone matrix of the MWNTs coated with a siloxane network, on the one hand, and the covalent links created between the terminal-vinyl groups and the host matrix in formation, on the other hand.