Linear and Nonlinear Rheology Combined with Dielectric Spectroscopy of Hybrid Polymer Nanocomposites for Semiconductive Applications
Artikel i vetenskaplig tidskrift, 2017

The linear and nonlinear oscillatory shear, extensional and combined rheology-dielectric spectroscopy of hybrid polymer nanocomposites for semiconductive applications were investigated in this study. The main focus was the influence of processing conditions on percolated poly(ethylene-butyl acrylate) (EBA) nanocomposite hybrids containing graphite nanoplatelets (GnP) and carbon black (CB). The rheological response of the samples was interpreted in terms of dispersion properties, filler distortion from processing, filler percolation, as well as the filler orientation and distribution dynamics inside the matrix. Evidence of the influence of dispersion properties was found in linear viscoelastic dynamic frequency sweeps, while the percolation of the nanocomposites was detected in nonlinearities developed in dynamic strain sweeps. Using extensional rheology, hybrid samples with better dispersion properties lead to a more pronounced strain hardening behavior, while samples with a higher volume percentage of fillers caused a drastic reduction in strain hardening. The rheo-dielectric time-dependent response showed that in the case of nanocomposites containing only GnP, the orientation dynamics leads to non-conductive samples. However, in the case of hybrids, the orientation of the GnP could be offset by the dispersing of the CB to bridge the nanoplatelets. The results were interpreted in the framework of a dual PE-BA model, where the fillers would be concentrated mainly in the BA regions. Furthermore, better dispersed hybrids obtained using mixing screws at the expense of filler distortion via extrusion processing history were emphasized through the rheo-dielectric tests.

extensional rheology

graphite nanoplatelets

polymer nanocomposites

carbon black

electrical conductivity

shear rheology

Författare

Roland Kádár

Chalmers, Material- och tillverkningsteknik, Polymera material och kompositer

Mahdi Abbasi

Karlsruher Institut für Technologie (KIT)

Roxana Figuli

Karlsruher Institut für Technologie (KIT)

Mikael Rigdahl

Chalmers, Material- och tillverkningsteknik, Polymera material och kompositer

Manfred Wilhelm

Karlsruher Institut für Technologie (KIT)

Nanomaterials

20794991 (eISSN)

Vol. 7 23

Styrkeområden

Nanovetenskap och nanoteknik

Materialvetenskap

Ämneskategorier

Textil-, gummi- och polymermaterial

Annan materialteknik

DOI

10.3390/nano7020023