Flame retardant mechanisms of phosphorus‐containing polyhedral oligomeric silsesquioxane (DOPO‐POSS) in polycarbonate composites

Abstract

AbstractThe flame retardancy mechanisms of a novel polyhedral oligomeric silsesquioxane containing 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO‐POSS) in polycarbonate (PC) composites are discussed. A nice flame retardancy performance of 6 wt % DOPO‐POSS/PC is detected from cone calorimeter testing. The peak heat release rate and total heat released of 6 wt % DOPO‐POSS/PC decrease obviously compared with that of PC. The major pyrolysis products detected from the decomposition process of PC and 6 wt % DOPO‐POSS/PC are investigated by TGA coupled with Fourier transform infrared spectrometry and mass spectrum (TGA‐FTIR and TGA‐MS), respectively. It is confirmed that DOPO‐POSS catalyzes thermal decomposition of PC, however, reduces the release of flammable volatiles during the decomposition of PC. The condensed phase products after decomposition of PC and 6 wt % DOPO‐POSS/PC are investigated by FTIR, scanning electron microscopy, energy dispersive X‐ray spectroscopy, and X‐ray photoelectron spectroscopy characterizations. They indicated that DOPO‐POSS can accelerate the formation of char during the decomposition of PC composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012