Thermal and Flammability Properties of a Silica-PMMA Nanocomposites.
Thermal and Flammability Properties of a Silica-PMMA
Nanocomposites.
(325 K)
Morgan, A. B.; Antonucci, J. M.; VanLandingham, M. R.;
Harris, R. H., Jr.; Kashiwagi, T.
Polymeric Materials Science and Engineering, Vol. 83,
57-58, 2000.
Keywords:
nanocomposites; thermal properties; flammability;
polymethyl methacrylate
Abstract:
The properties of a polymer composite material depend
not only upon the properties of the individual
components, but also upon the polymer's phase morphology
and interfacial properties with the other component. If
the area of the interface between the two components
becomes significantly large, the latter consideration,
or interphase, becomes of primary importance in
determining the overall properties of the composite
material. For example, polymers filled with nanoscale
silica particles generated a second glass transition
that was much higher than that of the polymer resins.
This phenomenon was accounted for by the formation of
tightly and loosely bound polymer chains around the
particles. Other studies reported an improvement in
physical properties and also some improvement in thermal
stability. An improvement in flammability properties of
polymers using the concept of enhanced interfaces with
layered silicates has been demonstrated for
clay-nanocomposites. In this study, the use of
nanoscale silica particles as a flame retardant
additive, in a polymer nanocomposite is investigated
with regard to improvements in both the flammability
properties and the physical properties of poly(methyl
methacrylate) (PMMA). In contrast, conventional flame
retardant additives, such as brominated compounds and
hydrides, improve flammability of polymers but tend to
reduce their physical properties.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899