Patent ID: 6518453
Filing Date: 2003-02-11
Classification: C07B,C07C

Abstract:
A process for stabilising chemical compounds which are present as pure substance or as a component of mixtures and have at least one ethylenically unsaturated group to undesired free radical polymerisation, in which polymerisation inhibitors which contain:a) at least one nitroxyl radical (inhibitors a)) and b) at least one chemical compound containing the element phosphorus in chemically bonded form (inhibitor b)) are added to the pure substance or the mixture, wherein the at least one inhibitor b) contains on the one hand no N-oxyl group and on the other hand at least a part of the phosphorus chemically bonded with an oxidation number ON of âˆ’3&lE;ON&lE;+5, this phosphorus simultaneously being covalently bonded to at least one hetero atom different from carbon.