Novel synergistic flame-retardant system of Mg-Al-Co-LDHs/DPCPB for ABS resins

Acrylonitrile-butadiene-styrene (ABS) resins are widely used in many sectors of the industry due to excellent mechanical properties, low temperature resistance, heat resistance, and chemical resistance. However, its flammability constitutes a key limitation in their applications. Consequently, development of flame-retarding ABS resins is imperative. Herein, we report a novel synergistic system composed of Mg-Al-Co-layered double hydroxides (LDHs) prepared via a co-precipitation method, and [4-(diphenoxy-phosphorylamino)-6-phenyl-[l,3,5] triazin-2-y1]-phosphoramidic acid diphenyl ester (DPCPB), a novel intumescent flame retardant. The properties of the as-prepared LDHs/DPCPB/ABS composites are evaluated using standard combustion performance tests including limiting oxygen index (LOI) and vertical burning test (UL-94). Novel ABS resins with the composition of ABS/DPCPB=100/25 and ABS/DPCPB/LDHs=100/2l/4 exhibit higher LOIs, 23.9 and 24.7, respectively, compared to 18.1 for the pure ABS. Meanwhile, they meet the V-2 and A-1 level, respectively, in UL-94 tests. Moreover, the prepared composites exert flame-retarding effects in gas phase and condensed phase simultaneously. Our results reveal synergistic effects between Mg-Al-Co-LDHs and DPCPB for the flame retardation of ABS resins. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46319.