Preparation of core−shell structured carbon nanotube-silsesquioxane hybrids by a direct free-radical reaction

• We prepared the core−shell structured POSS-coated CNT hybrids by a radical reaction.
• The POSS shell was in situ crosslinked on a CNT surface with adjustable thickness.
• The electrical performance of hybrids was controlled with varied shell thicknesses.
• This approach has industrial potential owing to the radical initiators and reaction.

Traditional methods to functionalize carbon nanotubes (CNTs) for preparing composites involve complex acid-treatment processing. In this study, a synthetic strategy is reported to prepare crosslinked octa-methacrylate polyhedral oligomeric silsesquioxane (POSS) coated multi-walled CNTs (MWCNTs) by direct in situ free-radical polymerization in a controlled manner. A series of core−shell structured hybrids with MWCNT at the center were obtained. The thickness of the shell was adjusted from about 5, 15, 25, to 40 nm. The hybrids of coated MWCNTs were well dispersed in the organic solvent and showed a controlled electrical performance (from 0.75 Ω cm to 2505 Ω cm) with varied coating layer thicknesses. The process is well suited for industrial production on larger surfaces.