In-situ co-precipitation synthesis of Zn/Fe-LDH modified melamine polyphosphate for enhanced flame retardancy in polypropylene

In this study, a novel approach was employed to enhance the flame retardant efficiency of an intumescent flame retardant (IFR) by growing a layered double hydroxides (LDHs) of Zn/Fe on the surface of melamine polyphosphate (MPP), denoted as Zn/Fe-LDH@MPP (LDHMPP). This modification was carried out via in-situ co-precipitation, and the resulting composite was subsequently applied to polypropylene (PP) in conjunction with piperazine pyrophosphate (PAPP). Under the same proportion and concentration, the PP/16 %LDHIFR formulation achieved a preferred V-0 rating in the UL-94 test. Furthermore, this formulation exhibited an enhanced ability to form a protective char layer, as evidenced by both cone calorimetry tests (CCT) and thermogravimetric analysis (TGA) tests. Additionally, the synergistic effect of Zn/Fe-LDH on flame retardancy was also studied.