Abstract: Disclosed is a process for inhibiting polymerization of polymerizable ethylenically unsaturated monomers such as hydrocarbons, acids and esters, wherein manganese nitrite, i.e. Mn(NO.sub.2).sub.2, is employed as an inhibitor. A composition including a polymerizable ethylenically unsaturated monomer and Mn(NO.sub.2).sub.2 is also disclosed. In two preferred embodiments, acrylic acid and styrene, respectively, are the monomers.

Abstract: Disclosed is a process for inhibiting polymerization of polymerizable ethylenically unsaturated monomers such as hydrocarbons, acids and esters, wherein a cobalt (III), nickel (II) or manganese (II) complex of N-nitrosophenylhydroxylamine is employed. A composition including a polymerizable ethylenically unsaturated monomer and the complex is also disclosed. In a preferred embodiment, polymerization of an acrylic acid or an acrylate ester is inhibited.

Abstract: Bis(aminophenyl) ethers are prepared by effecting condensation reaction of an (N-acetyl)aminophenol or the corresponding sodium or potassium (N-acetyl)aminophenate with a halonitrobenzene under condensation reaction conditions to form an (N-acetyl)aminophenylnitrophenyl ether and hydrogenating the nitro group thereof under nitro- group hydrogenation conditions to form an (N-acetyl)bis(aminophenyl) ether. The latter compound is hydrolyzed with aqueous mineral acid under acid hydrolysis conditions to form an acidic aqueous dispersion of the bis(aminophenyl) ether product, which can readily be recovered from the disperson. Final bis(aminophenyl) ether products thus prepared are typically of high purity and excellent color properties, i.e., substantially colorless.