Patent ID: 8551364

Claim:
A process for inhibiting polymerization of styrene or a styrene derivative having a polymerizable vinyl group which comprises adding a polymerization inhibitor composition consisting essentially of component (A) a nitrogenous aromatic compound represented by the following general formula (III) in combination with component (B) a sulfonic acid compound represented by the following general formula (V) during the stage of producing, purifying, storing or transporting of the styrene or styrene derivative wherein R 16 -R 25 represent independently hydrogen, hydroxyl group, a straight or branched chain alkyl group having from 1 to 12 carbon atoms, a straight or branched chain alkenyl group having from 2 to 12 carbon atoms, an aryl group having from 6 to 14 carbon atoms, an amino group, mono- or di-alkyl amino group whose alkyl group is a straight or branched chain having from 1 to 12 carbon atoms, a mono- or di-aryl amino group whose aryl group has from 6 to 12 carbon atoms, a formyl group, a carboxyl group, a carbamoyl group and a sulfonic acid residue, and adjacent two substituent groups may take an alicyclic or an aromatic cyclic structure together, and wherein R 32 represents a hydroxyl group, a straight or branched chain alkyl group having 1-32 carbon atoms, an alkylphenyl group wherein the alkyl group is a straight or branched chain alkyl having 1-32 carbon atoms or an alkylnaphthyl group wherein the alkyl group is a straight or branched chain alkyl having 1-32 carbon atoms.