Time resolved strain dependent morphological study of electrically conducting nanocomposites

[摘要] An efficient and reliable method is introduced to understand the network behaviour of nano-fillers in a polymeric matrix under uniaxial strain coupled with small angle x-ray scattering measurements. The nanoparticles (carbon nanotubes) are conductive and the particles form a percolating network that becomes apparent source of electrical conduction and consequently the samples behave as a bulk conductor. Polyurethane based nanocomposites containing 2% w/w multiwall carbon nanotubes are studied. The electrical conductivity of the nanocomposite was (3.28×10-5s/m).The sample was able to be extended to an extension ratio of 1.7 before fracture. A slight variation in the electrical conductivity is observed under uniaxial strain which we attribute to the disturbance of conductive pathways. Further, this work is coupled with in- situ time resolved small angle x-ray scattering measurements using a synchrotron beam line to enable its measurements to be made during the deformation cycle. We use a multiscale structure to model the small angle x-ray data. The results of the analysis are interpreted as the presence of aggregates which would also go some way towards understanding why there is no alignment of the carbon nanotubes.

[发布机构] Centre for Rapid and Sustainable Product Development, Institute Polytechnic Leiria, Marinha Grande, Portugal^1;NCD Beamline, Alba Synchrotron Light Source, Cerdanyola del Vallès, Barcelona, Spain^2

[效力级别] 数学

[关键词] Conducting nanocomposites;Electrical conduction;Electrical conductivity;Morphological study;Multi-scale structures;Percolating networks;Synchrotron beamlines;Time resolved small-angle x-ray scattering