Utilizing 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) as catalyst, alkyl functionalized multi-walled carbon nanotubes (alkyl-MWNT) were prepared by the esterification reaction of bromoalkane and carboxyl. To graft alkyl with different chain lengths onto MWNT, bromoalkanes with different numbers of carbon atoms, e.g. 1,6-dibromohexane, 1-bromooctane, 1-bromododecane and 1-bromohexadecane, were used to react with MWNT, which was pretreated with concentrated nitric acid. The prepared alkyl-MWNT can be readily dispersed in organic solvents, such as dichloromethane and chloroform, and the dispersibility increases with the increment of the alkyl chain length.

Key words: carbon nanotube, esterification reaction, chemical functionalization, bromoalkane