Oxygen index of various plastics

Thread Content

The oxygen index of various plastics, abbreviated as OI, is the lowest oxygen concentration required for a sample to maintain a steady combustion in a mixture of oxygen and nitrogen gases under specified conditions, expressed as a volume percentage of oxygen. A high oxygen index indicates that a material is difficult to burn, while a low oxygen index suggests that the material burns easily. Generally, an oxygen index of 27 is considered to indicate a flame-retardant material. The oxygen indices of various plastics are shown in the table below: Plastic type Oxygen index Polyoxymethylene (POM) 14.9 (flammable) Polyurethane (PU) 17 (flammable) Polymethyl methacrylate (PMMA) 17.3 (flammable) Polyethylene (PE) 17.4 (flammable) Polypropylene (PP) 18 (flammable) Polystyrene (PS) 18.1 (flammable) Acrylonitrile-butadiene-styrene (ABS) 18.2 (flammable) Polybutylene (PB) 18.3 (flammable) Polybutylene terephthalate (PBT) 20 (flammable) Polyethylene terephthalate (PET) 20.6 (flammable) Polyamide (PA66) 24.3 (combustible) Polycarbonate (PC) 24.9 (combustible) Polyphenylene oxide (PPO) 28 (difficult to ignite) Rigid polyvinyl chloride (PVC) 36 (difficult to ignite) Polyphenylene sulfide (PPS) 45 (difficult to ignite) Polyvinylidene chloride (PVDC) 60 (difficult to ignite) Polytetrafluoroethylene (PTFE) 95 (difficult to ignite)