Co-continuous nanostructured nanocomposites by reactive blending of carbon nanotube masterbatches

Masterbatches of reactive polymers containing carbon nanotubes are used to prepare nanocomposites by reactive blending. By mixing masterbatches of low molecular-weight amino-terminated polyamide-6 (PA6) containing similar to 10 wt% or similar to 17 wt% of multi-walled carbon nanotubes (MWNT) with maleic anhydride functionalized polyethylene (PE*) at temperatures above melting of PA6 it is possible to obtain fine and homogeneous dispersions of carbon nanotubes. In the PA6 concentration range explored, from 19 wt % to 37 wt%, nanostructured co-continuous blend morphologies are achieved. Selective extractions show that a high amount of graft copolymer PE*-g-PA6 is synthesized during mixing. The swelling experiments in selective solvents demonstrate co-continuous blend morphologies. Electron microscopy confirms good quality of MWNT dispersion and shows structures on mesoscopic scales. Fine dispersion of carbon nanotubes and the matrix co-continuity concur to yield a unique combination of properties such as solvent resistance, electrical conductivity, mechanical strengthening and ductility. (C) 2012 Elsevier Ltd. All rights reserved.