Fire performance of piperazine phytate modified rigid polyurethane foam composites

Abstract

Using phytic acid (PA) and piperazine (Pi) as raw materials, piperazine phytate (PA‐Pi) was fabricated by simple ionic reaction. Furthermore, A series of rigid polyurethane foam/piperazine phytate (RPUF/PA‐Pi) composites were prepared by one‐step water‐blown technology. Thermogravimetric (TG) results showed that the addition of PA‐Pi improved the thermal stability of RPUF/PA‐Pi composites at high temperature. At 700°C, RPUF/PA‐Pi20 exhibited the highest carbon residue of 25.8 wt%. Cone calorimetry and smoke density tests suggested that PA‐Pi could reduce the heat and smoke release during combustion process of the composites, thus reducing their fire hazard. Thermogravimetric‐Fourier transform infrared spectroscopy (TG‐FTIR) indicated that PA‐Pi significantly inhibited the release of toxic gases (isocyanate compounds, aromatic compounds, CO and HCN) and flammable gases (hydrocarbons and esters) during the decomposition process of RPUF/PA‐Pi composites, effectively improving fire performance of the composites. Scanning electron microscope (SEM), Raman and Fourier transform infrared spectroscopy (FTIR) were used to characterize the carbon residue of RPUF/PA‐Pi composites. The results showed that PA‐Pi could promote the formation of dense carbon layer of composites and effectively prevented heat and mass transfer in the combustion process.