Surface initiated grafting of polymer chains on carbon nanotubes via one-step cycloaddition of diarylcarbene

In the present study, we report a direct and nondestructive method to functionalize carbon nanotubes (CNTs). Novel highly reactive diarylcarbene derivative is designed and synthesized. Different to previous approaches, this diarylcarbene contains atomic transfer radical polymerization (ATRP) initiator segments, which can serve as starting points for further polymer grafting. Then, the initiator segments are covalently bonded to the CNTs via one-step cycloaddition of diarylcarbene and the succeeding ATRP links polystyrene (PS) chains to the CNTs. In order to further verify the effectiveness of modification, we use the obtained CNTs (PS-fCNTs) as reinforcement to enhance PS films. By addition 0.5 wt% PS-fCNTs, the PS composite films reveal 79.3 and 85.2% increases in tensile strength and Young's modulus. The protocol is believed to offer alternate strategy to modify the CNTs and greatly expand the application field of CNTs in material science.