Patent ID: 8691994

Claim:
A method of inhibiting the unwanted polymerization of an ethylenically unsaturated monomer prone to polymerization, wherein the ethylenically unsaturated monomer is selected from a list of acrylonitrile, (meth)acrolein, (meth)acrylic acid, acrylate esters, butylacrylate, ethylacrylate, methyl methacrylate, ethylene, propylene, styrene, divinylbenzene, vinyl acetate, vinyl alcohol, and any combination thereof, the method comprising the steps of: a) providing a nitroxide stable free radical solution having a solvent; b) adding a sufficient amount of dialkyl/aryl hydroxylamine to the solution to reduce the nitroxide to the nitroxide hydroxylamine; c) adding to the solution a polymerization prevention component, thereby forming an inhibiting composition; and d) adding the composition to a fluid containing ethylenically unsaturated monomers; wherein the polymerization prevention component is one selected from the list consisting of phenolic antioxidants, phenylenediamine and phenylenediamine derivatives, phenothiazine and phenothiazine derivatives, and any combinations thereof, and the polymerization prevention component is targeted towards ethylenically unsaturated monomers, and the polymerization prevention component is an item that would otherwise react with the nitroxide stable free radical but for the conversion of the nitroxide into nitroxide hydroxylamine.