Menue

Publications

Authors McNally, T. ; Pötschke, P. ; Halley, P. ; Murphy, M. ; Martin, D. ; Bell, S.E.J. ; Brennan, G. P. ; Bein, D. ; Lemoine, P. ; Quinn, J. P.
Title Polyethylene multiwalled carbon nanotube composites
Date 30.08.2005
Number 13043
Abstract Polyethylene (PE) multiwalled carbon nanotubes (MWCNTs) with weight fractions ranging from 0.1 to 10 wt% were prepared by melt blending using a mini-twin <br />screw extruder. The morphology and degree of dispersion of the MWCNTs in the PE matrix at different length scales was investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and wide-angle X-ray diffraction (WAXD). Both individual and agglomerations of MWCNTs were evident. An up-shift of 17 cm-1 for the G band and the evolution of a shoulder to this peak were obtained in the Raman spectra of the nanocomposites, probably due to compressive forces exerted on the MWCNTs by PE chains and indicating intercalation of PE into the MWCNT bundles. The electrical conductivity and linear viscoelastic behaviour of these nanocomposites were investigated. A percolation threshold of about 7.5 wt% was obtained and the electrical conductivity of PE was increased significantly, by 16 orders of magnitude, from 10-20 to 10-4 S/cm. The storage modulus (G') versus frequency curves approached a plateau above the percolation threshold with the formation of an interconnected nanotube structure, indicative of ‘pseudo-solid-like’ behaviour. The ultimate tensile strength and elongation at break of the nanocomposites decreased with addition of MWCNTs. The diminution of mechanical properties of the nanocomposites, though concomitant with a significant increase in electrical conductivity, implies the mechanism for mechanical reinforcement for PE/MWCNT composites is filler-matrix interfacial interactions and not filler percolation. The temperature of crystallisation (Tc) and fraction of PE that was crystalline (Fc) were modified by incorporating MWCNTs. The thermal decomposition temperature of PE was enhanced by 20 K on addition of 10 wt% MWCNT.
Publisher Polymer
Wikidata Q61703076
Citation Polymer 46 (2005) 8222-8232
DOI http://dx.doi.org/10.1016/j.polymer.2005.06.094
Tags polyethylene multiwalled carbon nanotubes nanocomposites electrical-conductivity mechanical-properties polymer nanocomposites polycarbonate rheology functionalization microtubules orientation dispersion

Back to list