High-throughput Method for Estimating the Time to Sustained Ignition of Polystyrene-Clay Nanocomposites Based on Thermogravimetric Analysis
Polymers for Advanced Technologies
Polymer-modified clay nanocomposites were prepared by melt blending and the time to ignition was measured by cone calorimetry at various heat fluxes. Based on these experimental results, a critical mass flux and critical percentage mass loss (pmlcrit) for piloted ignition were identified and validated for both virgin polystyrene and its composites, across a wide range of heating fluxes. Based on the assumption that the polymer degradation kinetics in the heating segment of the cone calorimetry (up to the moment of ignition) and thermogravimetry experiments are similar, and using the pmlcrit, we hypothesized that the onset degradation temperature of the TGA samples (defined here as the temperature at pmlcrit) could be used to estimate the time to sustained ignition in cone calorimetry experiments. The onset degradation temperature and the time to sustained ignition showed a good correlation, regardless of the heating flux used in cone calorimetry experiments.