Modified with ferrocenyl-containing oligo- and polysiloxanes multi-walled carbon nanotubes for soft conductive silicone composites

Surface modification of multi-walled carbon nanotubes (MWCNT) was achieved by covalent grafting of 1,3,5,7-tetra(2-ferrocenylethyl)-1,3,5,7-tetramethylcyclotetrasiloxane (Fc4D4) and in situ forming polyFc4D4 in the presence of catalytic mixture AlCl3 and metallic Al. For composite preparation, MWCNT modified with ferrocenyl-containing oligo- and polysiloxanes were incorporated into the silicone compound and high-quality soft flexible silicone composites was obtained. In a stress-strain tests of the obtained composites, elongation at break value was an approx. two times higher that in the initial silicone matrix. The conducted modification of MWCNT surface significantly improve dispersion of modified MWCNT in silicone polymer matrix even at higher filler concentration using simple solution blending method of composite preparation. The composites demonstrated conductivity at the level of semiconductors. [Display omitted] •Ferrocenyl-containing (poly)siloxanes were covalently grafted to MWCNT surface.•Compatibility between modified MWCNT and silicone matrix was improved.•Silicone composites with modified MWCNT demonstrate conductivity at the level of semiconductors.•Tensile properties of the silicone composites containing modified MWCNT were evaluated.