Ethylene-co-norbornene copolymers grafted carbon nanotube composites by in situ polymerization

摘要

Vinyl functionalized multiwalled carbon nanotubes (MWCNT-vinyl) are synthesized and used as monomers to prepare poly(ethylene-co-norbornene)-grafted carbon nanotube composites by in situ polymerization with Ti(· ~5-C _5Me _5)(N=C ~tBu _2)Cl _2 activated with methylalumoxane (MAO). The glass transition temperatures (T _g) of grafted MWCNT composites are more than 30 °C higher than those of copolymers. This difference is rationalized by the immobilization of the copolymer chain to the MWCNT surface by a covalent bond. The Young's modulus is shown to increase by more than 200 compared to poly(ethylene-co-norbornene) by incorporating 3.4 wt functionalized MWCNT.