Effects of Aspect Ratio of MWNT on the Flammability Properties of Polymer Nanocomposites.
Effects of Aspect Ratio of MWNT on the Flammability
Properties of Polymer Nanocomposites.
Cipiriano, B. H.; Kashiwagi, T.; Raghavan, S. R.; Yang,
Y.; Grulke, E. A.; Yamamoto, K.; Shields, J. R.;
Douglas, J. F.
Polymer, Vol. 48, No. 1620, 6086-6096, September 2007.
nanocomposites; flammability; aspect ratio; carbon;
rheology; polystyrene; experiments; particles; mass
loss; composite materials; morphology; viscoelasticity;
thermal stability; equations
The effects of the aspect ratio of multi-walled carbon
nanotubes (MWNTs) on the rheology and flammability of
polystyrene/MWNT nanocomposites are studied using two
MWNTs having average aspect ratios (length to outer
diameter) of 49 and 150. Dynamic rheological experiments
show that the particles with the larger aspect ratio
impart much higher storage moduli and complex
viscosities to the nanocomposites compared to equivalent
mass loadings of particles with the smaller aspect
ratio. Additionally, in flammability experiments, the
larger aspect ratio particles lead to a greater
reduction in mass loss rate, i.e., they are more
effective at reducing flammability. These results
demonstrate that the aspect ratio of MWNTs is a key
parameter in controlling the rheology and flammability
of polymer nanocomposites.