Surface modification of α‐zirconium phosphate by zeolitic imidazolate frameworks‐8 and its effect on improving the fire safety of polyurethane elastomer

Abstract

A novel type of ZIF‐8/α‐ZrP (zeolitic imidazolate frameworks‐8/α‐zirconium phosphate) hybrid was obtained through surface modification of α‐ZrP by ZIF‐8 and was characterized. Subsequently, ZIF‐8/α‐ZrP was added to polyurethane elastomer (PUE) by simple blending, and the thermal behavior, flame retardancy, and smoke suppression properties of the ZIF‐8/α‐ZrP hybrid on PUE were studied. Compared with pure PUE, the test results showed that the char yield of the ZIF‐8/α‐ZrP/PUE composite at 700°C and its Tg values were increased, respectively. The peak heat release rate and total heat release of the ZIF‐8/α‐ZrP/PUE composite decreased by 69.6% and 45.6%, respectively. Meanwhile, its smoke production rate and total smoke production decreased by 59.3% and 40.5%, respectively. The improved flame retardancy and smoke suppression were primarily ascribed to the physical barrier and catalytic carbonization effects of α‐ZrP. Furthermore, the metal oxide decomposed by ZIF‐8 could further facilitate the production of char residue and raise the compactness of the char layer.