▎ 摘　　要

NOVELTY - High carbon-forming and halogen-free composite expansion fire retardant comprise 1-20 pts. wt. phosphorus nitrogen and fire retardant, 1-20 pts. wt. carbon forming agent, where the phosphorus nitrogen fire retardant (I) USE - High carbon-forming and halogen-free composite expansion fire retardant for use in polypropylene plastic and fiber, polystyrenes foam plastic, unsaturated polyester, polycarbonate, polyethylene, and synthetic rubber. ADVANTAGE - The high-carbon halogen-free composite has simple, easy to realize industrial production, is green and environment-friendly, has excellent heat resistance, has a flame-retardant synergistic effect, and carbon-forming property, and has reduced polystyrene smoke amount, DETAILED DESCRIPTION - High carbon-forming and halogen-free composite expansion fire retardant comprise 1-20 pts. wt. phosphorus nitrogen and fire retardant, 1-20 pts. wt. carbon forming agent, where the phosphorus nitrogen fire retardant of formula (I). An INDEPENDENT CLAIM is included for flame-retardant polystyrene, which comprises high carbon-forming halogen-free composite expansion fire retardant and polystyrene.