Synthesis of a Triazine-Based Hyper Branched Macromolecule Charring Agent and its Effect on Flame-Retardant Thermoplastic Polyester Elastomer to Improve Anti-Dripping

A triazine-based charring agent (CDS) was synthesized and combined with diethyl aluminum hypophosphite (AlPi) to develop an intumescent flame retardant (IFR) system to improve thermoplastic polyester elastomer (TPEE) anti-dripping. The results showed that the limiting oxygen index (LOI) of the TPEE/15AlPi/5CDS composite reached 30.2%, and it passed the V-0 test in vertical combustion (UL-94). The results of thermogravimetric analysis (TGA) showed that CDS had good thermal stability and high char residue (50.8wt%) at 700°C. And when combined with AlPi added to TPEE, which can improve its char residue ranges from 1.68wt% to 23.52wt%. The structure evolution during the heating process was studied by heating infrared spectroscopy (IR), and the morphology and chemical structure of char residues were studied by scanning electron microscope (SEM) and laser Raman spectroscopy (LRS). The high-efficiency flame-retardant TPEE composite formed a continuous, dense and porous char layer containing triazine ring and aromatic ring structure after combustion.