Aluminum phosphate modified brucite and its flame retardant and smoke suppression performance onethylene-vinylacetate resin

A novel halogen-free flame retardant (FR) consisting of brucite, aluminum phosphate (AlP), and silane coupling agent (B/AlP/A) was prepared via co-precipitation assembly technique. The morphology, chemical compositions, size distribution, and thermal stability of B/AlP/A were investigated. When used in ethylene-vinyl acetate (EVA) resin, the B/AlP/A could significantly enhance the flame retardant and smoke suppression performance of the EVA composites, which is mainly attributed to the AIP. With 50 wt% FR loading, the peak heat release rate (PHRR) of EVA-B/AlP/A (299.2 kW center dot m(-2)) is much lower than that of EVA-B/A (387.4 kW center dot m(-2)). Moreover, B/AlP/A shows an excellent smoke suppression performance. For example, the smoke production rate is 0.017 m(2) center dot g(-1)that has been decreased by 72.1%, compared with B/A. The improvement arises from the amorphous AlP layer on brucite, which helps to create a firm and porous protective char layers on the burning EVA composites. Meanwhile, better mechanical property could be simultaneously obtained with the large FR amount. The fluffy surface of B/AlP/A has good compatibility with EVA and tangle more polymer chains, enhancing the mechanical properties. In a word, this simple and convenient method could pave the way for developing a more efficient and cost-effective brucite-based FR.

Automated summary

The novel halogen-free flame retardant B/AlP/A, consisting of brucite, aluminum phosphate, and silane coupling agent, showed significantly enhanced flame retardant and smoke suppression performance in EVA resin, mainly attributed to the amorphous AlP layer on brucite. The improved mechanical properties and reduced smoke production rate make it a promising and cost-effective fire retardant for EVA composites.