Polypropylene Flame Retardant Piperazine Pyrophosphate IFR-PAP01 Polypropylene Flame Retardant Piperazine Pyrophosphate IFR PAP01 with Low Smoke Density and Excellent Migration Resistance for Polymer IFR-PAP01 Piperazine Pyrophosphate is a halogen-free eco-friendly intumescent flame retardant with built-in carbon source and acid source. When compounded with selected gas source and acid source components, it forms a high-efficiency IFR system that enables polymers to pass UL94