NAUGARD® SFR inhibitor

NAUGARD® SFR inhibitor by SI Group is a sterically hindered nitroxyl stable free radical. It is used as a polymerization inhibitor in the manufacture of styrene monomer. This inhibitor is less toxic than dinitrophenols, reduces the molecular weight of polymer formed, so that polymer and tar viscosity are dramatically reduced. The recommended dosage of NAUGARD® SFR inhibitor is 25% at which it reduces polymer formation by 75%. It is successful in plants with reboiler temperatures as high as 126°C. It has a shelf life of approximately six months.