Combustibility of cyanate ester resins

Flaming and non-flaming combustion studies were conducted on a series of polycyanurates to examine the effect of chemical composition and physical properties on the fire behavior of these crosslinked, char forming, thermoset polymers. Heats of complete combustion of the polymer and fuel gases were determined by oxygen bomb calorimetry and pyrolysis-combustion flow calorimetry, respectively. Fire calorimetry experiments were conducted to measure the total heat released, the rate of heat release and the smoke generation in flaming combustion. Fire response parameters derived from the data include the thermal inertia, heat of gasification, effective heat of combustion and combustion efficiency. Halogen-containing polycyanurates exhibited extremely low heat release rate in flaming combustion compared with the hydrocarbon resins yet produced significantly less smoke and comparable levels of carbon monoxide and soot. Published in 2005 by John Wiley & Sons, Ltd.