A Green P-N-Al Synergistic System for Eco-Friendly Flame-Retardant Polystyrene

Area of Science:

• Materials Science
• Polymer Chemistry
• Fire Safety Engineering

Background:

• Polystyrene (PS) is a versatile polymer with widespread applications.
• Its high flammability poses significant safety risks.
• Developing effective halogen-free flame retardants for PS is a critical challenge.

Purpose of the Study:

• To develop a green, intumescent flame-retardant system for polystyrene.
• To evaluate the fire safety and mechanical performance of PS composites incorporating this system.
• To elucidate the flame-retardant mechanism of the developed system.

Main Methods:

• Sequential solution grinding and hot pressing were used to incorporate the flame retardant system into PS.
• Limiting Oxygen Index (LOI) and UL-94 tests were performed to assess fire safety.
• Mechanical properties, specifically tensile strength, were evaluated.
• Thermogravimetric analysis and cone calorimetry were used to study the flame-retardant mechanism.

Main Results:

• The optimal formulation (PS/10ADP/15PA-TETA) achieved an LOI of 28.5% and a UL-94 V-0 rating.
• Peak heat release rate and total heat release were reduced by 73.8% and 46.2%, respectively.
• The composite retained 78.4% of the tensile strength of neat PS.
• The ADP/PA-TETA system demonstrated a cooperative condensed-phase charring and gas-phase dilution mechanism.

Conclusions:

• The ADP/PA-TETA system offers an effective and eco-friendly solution for enhancing PS flame retardancy.
• This strategy achieves a balance between high fire safety and preserved mechanical properties in PS composites.
• The findings provide a viable pathway for fabricating high-performance, flame-retardant PS materials.