Summary: It is a big challenge to improve simultaneously both the flame retardancy and the melt‐dripping resistance of polymeric materials such as PET. In this paper, a novel intumescent flame retardant, DPSPB, was synthesized and blended with copolyester PET‐co‐DDP/O‐MMT nanocomposites, which were synthesized by polycondensation of TPA, EG, DDP, and O‐MMT. The resulting PET‐co‐DDP/O‐MMT/DPSPB nanocomposites exhibit very good flame retardance and dripping resistance, e.g., LOI = 29, UL‐94 V‐0. SEM, XRD, and XPS were used to investigate the relationships between the structures and properties of the composites. It is proved that DPSPB offers excellent protection for the structure of nanocomposites, which is responsible for the good anti‐dripping properties of the nanocomposites.
Residues of copolyesters after combustion: common nanocomposite residue of PDMN (left) and the novel nanocomposite residue of PDMN/DPSPB (right).
