Authors: P. Longo, C. Costabile, F. Grisi, N. Latorraca, P. Ciambelli, M. Sarno, C. Leone, D. Sannino
Affilation: University of Salerno, Italy
Pages: 756 - 759
Keywords: ROMP, MWNT, covalent bond, activity
The synthesis of “homogeneuos” polymeric composites containing multi-walled carbon nanotubes (MWNT), that could effectively combine the properties of carbon nanotubes with the solubility and processability of polymers, has emerged as one of the most important and challenging topics in the area of nanostructured materials. The main approaches to obtain “homogeneous” nanocomposites aim to set up a covalent bond polymer-carbon nanotube. In particular, for the “grafting from” approach, catalyst functionalized nanotubes behave as polymerization initiators. Herein, the synthesis of polynorbornene by ring opening metathesis polymerizations (ROMP) in the presence of 2nd generation Grubbs catalyst-functionalized nanotube initiators 1-4 is reported. All initiators have a Grubbs catalyst linked to the nanotube through “chemical arms” differing for the alcoholic group connecting the catalyst to the –COOH functionality of the MWCNTs. A full characterization of the Grubbs catalyst-functionalized nanotubes was performed by FTIR and TG-DTG coupled with Mass Spectrometer in order to quantify the amount of catalyst grafted to the nanotube. The activities of 1-4 depend on the length of the arm connecting the catalyst to the nanotube. These results can be rationalized by considering the lower accessibility of the monomer to the catalyst grafted to the nanotube through a shorter arm.