Improving fire safety of thermoplastic poly(ether ester) elastomer by black phosphorus nanosheets and aluminum diethylphosphinate system

Thermoplastic poly(ether ester) elastomer (TPEE) is a highly flammable material with severe melt-dropping, which greatly limits its range of applications. Here, black phosphorus nanosheets (BPs) and aluminum diethylphosphinate (ADP) were used to improve the fire safety of TPEE for the first time. Results demonstrated that ADP/BPs as a synergistic combination exhibits good dispersity and excellent flame retardancy, also has minimal negative effects on the mechanical performances of the TPEE composites. By comparing TPEE/ADP-22 and TPEE/ADP-10/BPs-4, the introduction of BPs significantly reduced the addition of ADP while keeping the material at the higher vertical burning grade, ~54.5% reduction in ADP usage. Compared with neat TPEE, TPEE/ADP-10/BPs-4 fulfilled V-0 level, avoided dripping, and the limiting oxygen index value increased to 34.0%. Moreover, TPEE/ADP-10/BPs-4 performed the best in cone calorimetry test, both the peak heat release rate and total heat release reduced the largest, by 44.2% and 25.3%, respectively. The detailed studies of the flame-retardant mechanism found that ADP/BPs showed the fire-retardant impact of the condensed phase and gaseous phase. This work expands BPs in the flame-retardant application and could facilitate to prepare the anti-dripping flame-resistant TPEE.

Highlights

• BPs as an efficient flame retardant were added into TPEE for the first time.
• ADP/BPs as a synergistic combination has an excellent fire-retardant effect.
• The introduction of BPs significantly reduced the addition of ADP.
• TPEE/ADP-10/BPs-4 showed the highest FPI and the lowest FGI.
• ADP/BPs has lowest negative effects on the mechanical performances of matrix.