Definitions

There are a few terms that are helpful in discussing the flammability properties of polymers.

Amorphous: Non-crystalline and without long range order. Many polymers do not have crystalline structures, and therefore cannot be said to “melt.”

Melting temperature: In common language, we say that a solid “melts” when it turns to a liquid. In more formal language we generally understand “melt” to refer to heat-induced motion of molecules that causes the breakdown of crystalline structure.

Decomposition temperature: A measurement of the thermal stability of a polymer. Oxidation begins at the decomposition temperature. The decomposition temperature is shown in one of the tables to follow.

Polymer: Large molecules of nonmetallic elements composed of many repetitive units (mers). Commonly called plastics.

Vaporization temperature: Some polymers begin to vaporize before they appear to oxidize. In such cases, the vaporization temperature is a measure of thermal stability.