Application of the PAPP/MCA/APP intumescent flame retardant system in polypropylene

Abstract

AbstractAmmonium polyphosphate (APP), piperazine pyrophosphate (PAPP), and melamine cyanurate (MCA) were used as raw materials to develop an intumescent flame retardant system (IFRS) for polypropylene (PP). The synergistic flame retardancy among APP, PAPP, and MCA was explored. The effect of the proportion of APP, PAPP, and MCA on the IFRS flame‐retardant performance was studied. For the range of samples tested, the IFRS with the proportion of PAPP, MCA, and APP at 4:1:7.5 showed the best flame retardancy. When the addition of PAPP/MCA/APP IFRS in PP was 20%, the prepared flame‐retardant PP composite (PP‐PMA‐3) passed UL‐94 V‐0 rating. Moreover, the PP‐PMA‐3 total heat release (THR) decreased by 46.4% compared with PP‐0. Meanwhile, PAPP/MCA/APP IFRS showed good smoke suppression performance because the total smoke production (TSP) of PP‐PMA‐3 decreased by 65.0% compared with PP‐0. In addition, the high flame retardancy and the flame‐retardant mechanism of the prepared IFRS was explained.