Abstract: The present invention relates to the use of at least two phenol derivatives jointly with at least one ancillary polymerization inhibitor which is different from these two phenol derivatives and particularly is selected from phenol derivatives, amine derivatives, thiazine derivatives, nitroso compounds, N-oxyl derivatives, metal salts, quinone derivatives, and mixtures thereof, to inhibit the polymerization of ethylenically unsaturated monomers comprising at least one heteroatom, it being also possible for a dispersant to be incorporated. The present invention also relates to a corresponding polymerization-inhibiting composition and to the corresponding process for preparing ethylenically unsaturated monomers comprising at least one heteroatom, and particularly acrylic monomers.

Abstract: The present invention relates to the use of at least two phenol derivatives jointly with at least one ancillary polymerization inhibitor which is different from these two phenol derivatives and particularly is selected from phenol derivatives, amine derivatives, thiazine derivatives, nitroso compounds, N-oxyl derivatives, metal salts, quinone derivatives, and mixtures thereof, to inhibit the polymerization of ethylenically unsaturated monomers comprising at least one heteroatom, it being also possible for a dispersant to be incorporated. The present invention also relates to a corresponding polymerization-inhibiting composition and to the corresponding process for preparing ethylenically unsaturated monomers comprising at least one heteroatom, and particularly acrylic monomers.

Abstract: The invention describes a composition that inhibits the polymerization of ethylenically unsaturated monomers, including at least 98% by weight of 4-tert-butylcatechol (4-TBC), 0.03% to 0.2% by weight of catechol (PC), and at least one impurity selected among 3-tert-butylcatechol, tert-butylhydroquinone, 3,5-di-tert-butylcatechol and mixture thereof, the total quantity of said impurities and of the PC being 0.1% to 0.8% by weight of said composition. The invention also describes a method for removing said polymerization-inhibiting composition present in a mixture including at least one ethylenically unsaturated monomer.

Abstract: The invention describes a composition that inhibits the polymerization of ethylenically unsaturated monomers, including at least 98% by weight of 4-tert-butylcatechol (4-TBC), 0.03% to 0.2% by weight of catechol (PC), and at least one impurity selected among 3-tert-butylcatechol, tert-butylhydroquinone, 3,5-di-tert-butylcatechol and mixture thereof, the total quantity of said impurities and of the PC being 0.1% to 0.8% by weight of said composition. The invention also describes a method for removing in said polymerization-inhibiting composition present in a mixture including at least one ethylenically unsaturated monomer.