Exploring the Role of Polymer Melt Viscosity in Melt Flow and Flammability Behavior.
Exploring the Role of Polymer Melt Viscosity in Melt
Flow and Flammability Behavior.
Ohlemiller, T. J.; Shields, J. R.; Butler, K. M.;
Collins, B.; Seck, M. D.
New Developments and Key Market Trends in Flame
Retardancy. Fall Conference. Proceedings. Fire
Retardant Chemicals Association. October 15-18, 2000,
Ponte Vedra, FL, Fire Retardant Chemicals Assoc.,
Lancaster, PA, 1-28 pp, 2000.
flame retardants; polymers; flammability; viscosity;
Thermoplastic polymers are widely used in roles where
molding facilitates cost effective, high volume
applications. Such polymers exhibit uniquely complex
behavior in a fire because of their tendency to liquefy
and flow. This behavior was explored in two stages. In
the first, the melt behavior was examined in a
non-flaming situation that subjected one face of a
polymer slab to a radiant heat flux. The transient flow
behavior was recorded for comparison to a model that
uses the separately-measured melt viscosity as an input.
In the second stage of the study, the burning behavior
was examined in a facility that allows heat release rate
measurements. These experiments explored the sensitivity
of the evolved heat release rate to polymer type,
polymer melt viscosity and physical aspects of the
experimental set-up. The results demonstrate that the
burning behavior of a thermoplastic object can vary
strongly with the conditions under which it is burned if
its melt viscosity permits appreciable flow.