Article

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

Journal of Materials Science (Impact Factor: 2.31). 07/2009; 44(13):3476-3482. DOI: 10.1007/s10853-009-3464-1

ABSTRACT 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 0.2wt%,
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.

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