The influence of carbon-encapsulated transition metal oxide microparticles on reducing toxic gases release and smoke suppression of rigid polyurethane foam composites

Abstract

The rapid development and massive consumption of rigid polyurethane foams (RPUF) has drawn attention to their fire safety related problems, such as the heat release and notable generation of smoke and toxic gases in fire. Three novel types of carbon-encapsulated transition metal oxide microparticles, Cu@C, Fe2O3@C and Cu2O@Fe2O3@C, were prepared via a simple hydrothermal method in this research. Potential smoke and toxicity suppression by the as-prepared carbon-encapsulated hybrids in flame-retardant RPUF composites with ammonium polyphosphate (APP) and dimethylmethylphosphonate (DMMP) were investigated. Compared with pure RPUFs, the peak heat release rate (pHRR) value of RPUF/A5-D5/5.0Fe2O3@C decreased by 40.5%, indicating the obvious improved flame retardancy. Besides, the related mechanisms of smoke suppression and toxic based on the catalytic effect of transition metal oxide was also proposed on the basis of experiment results.