Synergistic effects of BHDB-IPC with AlPi/MCA on flame retarding TPEE

Abstract

The deoxybenzoin-based copolyarylate BHDB-IPC with perfect charring ability was synthesized. The synergistic effects of BHDB-IPC as a charring agent in TPEE flame retarded by the phosphorous–nitrogen flame retardant (P–N FR) based on AlPi/MCA were studied using the limiting oxygen index (LOI), UL94 test, thermogravimetric analysis (TGA), temperature dependent FTIR, laser Raman spectroscopy (LRS), and scanning electron microscopy (SEM). The UL94 test showed that with BHDB-IPC added, TPEE/P–N FR systems had a synergistic FR effect in condensed phase with AlPi. The TGA data illustrated that BHDB-IPC increased the thermal stability of the TPEE/P–N FR systems and especially the residues at high temperature (T > 700 °C). The synergistic mechanisms between AlPi and BHDB-IPC were analyzed from the temperature dependent FTIR. The residues were analyzed with LRS and SEM, which could provide useful information on the carbonaceous microstructures and the morphological structures. It was demonstrated that BHDB-IPC promoted the formation of stable and compact carbonaceous char, which could prevent the melt dripping and improve the flame retardancy. Thus, BHDB-IPC was a promising synergist for the P–N flame retardant in TPEE.