Cone Calorimeter Combustion and Gasification Studies of Polymer Layered Silicate Nanocomposites.
Cone Calorimeter Combustion and Gasification Studies of
Polymer Layered Silicate Nanocomposites.
Zanetti, M.; Kashiwagi, T.; Falqui, L.; Camino, G.
Chemistry of Materials, Vol. 14, No. 2, 881-887,
nanocomposites; cone calorimeters; combustion;
gasification; experiments; heat flux; x ray diffraction
Polymer composites based on organically modified
phyllosilicates (organoclay) and poly(ethylene-co-vinyl
acetate) (EVA) were prepared by melt processing to study
their combustion behavior. Their degrees of dispersion
and intercalation spacings as determined by transmission
electron microscopy (TEM) and X-ray diffraction (XRD)
were typical of either a microcomposite or an exfoliated
nanocomposite, depending on the type of organoclay.
Combustion experiments showed that the microcomposite
burns in the same way as pure EVA, whereas the heat
release is reduced by 70-80% when nanocomposites with
low silicate loadings (2-5%) are burned, because a
protective charred ceramic surface layer is formed as a
result of reassembly of the clay layers and catalyzed
charring of the polymer. A chemical mechanism for this
charring is proposed.