Authors: C. Semaan, G. Pecastaings, M. Schappacher, A. Soum
Affilation: Laboratoire de Chimie des Polymères Organiques LCPO, France
Pages: 219 - 222
Keywords: carbon nanotubes, amphiphilic block copolymers, nanocomposite, percolation threshold
The scope of carbon nanotubes (CNT) applications in practical devices has been hampered by poor dispersion and weak interfacial bonding with polymer matrices. Therefore, effective method for CNT dispersion is required for industrial applications. We report our success in wrapping Multi-wall carbon nanotubes (MWCNT) with amphiphilic block copolymers in aqueous solution. We selected poly(ethylene oxide) (PEO) as hydrophilic block, while for hydrophobic block we used one of the following polymers: polyethylene, polybutadiene, polystyrene, poly(propylene oxide), polythiophene. Based on the collected data analysis, we could establish the influence on CNT dispersion quality of the molar mass of copolymers, the nature and the length of the hydrophobic block. A key aspect of our study was our findings related to nanocomposites composed of the PEO or poly(methyl methacrylate)-wrapped MWCNT. We investigated by means of their rheological and electrical percolation behavior in order to obtain information about the structure and the dispersion of the nanoparticles in the polymer matrix. In terms of the rheological behavior, we observed a progression from liquid-like to solid-like behavior and two rheological percolations; one at 0.085wt% MWCNT and another one at 2wt% MWNCT. Electrical measurements showed one electrical percolation at 2wt% MWCNT. Mechanical properties of nanocomposites were also investigated.