Theory
2.1. First component of flammability e ease of ignition
As heating of a polymer occurs, a temperature rise of the polymer
cause it to go through melting, degradation, and decomposition
into smaller molecules (oligomers, monomers and smaller
decomposition products). Vapors of the smaller molecules can be
ignited if the mixture is within its flammability limits. The lower
the ignition temperature, the higher the flammability, and a higher
need for flame retardants to prevent or delay ignition.
2.2. Second component of flammability e speed of burning
Once a polymer is ignited, the amount of heat generated will
sustain combustion. So, the important parameter for the speed of
burning is the heat release rate. Babrauskas & Peacock [3] state that
the heat release capacity is the most important variable in predicting
flammability. This is because heat release capacity is
directly proportional to the heat release rate demonstrated by
Walters and Lyon [4] and Walters [5]. Heat release capacity has
units equivalent to heat capacity (energy/mass-degree), and is
related to the heat of combustion released per degree temperature