The thermal properties of rigid polyurethane foams treated with flame retardant

A novel cheap macromolecular intumescent flame retardants (MIFR), was synthesized, and its structure was a caged bicyclic macromolecule containing phosphorus characterized by IR. Rigid polyurethane foam (PUF) were modified with MIFR to get the flame retardant PUF, whose flammability and burning behavior were characterized by UL 94 and limiting oxygen index (LOI). 25% of weight of MIFR were doped into PUF to get 24.5 of LOI and UL 94 V-0. The thermal properties of epoxy resins containing MIFR were investigated with thermogravimetry (TG). Activation energy for the decomposition of samples was obtained using Kissinger equation. The resultant data show that for PUF containing MIFR, compared with PUF, MIFR decreased weight loss, thermal stability, increased the char yield. The activation energy for the decomposition of EP is 205 kJ/mol while it becomes 162 kJ/mol for PUF containing MIFR, decreased by 42 kJ/mol, which shows that IFR can catalyze decomposition and carbonization of PUF.