Combustion behavior of polypropylene-based composites used in industrial plasticollar

Abstract

In this research, we investigated the effect of two types of flame retardants, such as ammonium polyphosphate (Exolit AP 760 – trademark) (EXOLIT) and magnesium hydroxide (Magnifin H5 GV – trademark) (MH) on burning polypropylene (PP) filled either with calcium carbonate (CCPP) or with talc (TPP) by means of number of techniques, such as Cone Calorimeter, limiting oxygen index (LOI), and UL94 tests. A significant decrease in the heat release rate, depending by the type of flame retardant used, was observed. Furthermore, with the consideration that the life safety during the fire could be improved by a decrease in the fire hazard, a decrease in the quantity of smoke, depending also on the type of flame retardant, was revealed. With regard to the LOI test, EXOLIT has a little influence on flame retardancy of the CCPP and TPP matrices, whereas MH showed a significant increase of flame retardancy on both types of composites. To understand the flame-retardancy mechanism of these CCPP and TPP composites, we thoroughly investigated their thermal decomposition behavior.

Keywords:

• flame retardance
• polypropylene
• calcium carbonate
• talc
• ammonium polyphosphate
• magnesium hydroxide

Acknowledgments

The authors thanks Piedmont Region for the financial support for the Plasticollar project in the Industrial Research call 2008.