GB1347068A - Highly stable anaerobic compositions - Google Patents

Abstract

1347068 Anaerobic curing compositions LOCTITE CORP 19 April 1971 [18 March 1970 4 Feb 1971] 24498/71 Heading C3P Anaerobic curing compositions comprise a polymerizable ester of acrylic acid or of an α- substituted acrylic acid (e.g. methacrylic or chloroacrylic acid), a peroxy polymerization initiator therefor, and dissolved therein a metal chelator having ligand atoms (e.g. N, O, S, Cl, Br, I, P, As and Se) other than an N atom which is part of a group. The metal chelator increases the stability of the composition and enables more active polymerization accelerators to be included therein. Preferred ester monomers are those containing at least two acrylic ester groups in the molecule or mono-acrylic esters containing a polar group. Hydroperoxides, in particular organic hydroperoxides, are preferred initiators, and also suitable are peroxides such as cyclohexyl hydroxycyclohexyl peroxide and t-butyl perbenzoate which form hydroperoxides in situ. Useful metal chelators include compounds such as tetrasodium ethylenediamine tetraacetic acid, o-aminophenol, salicylaldehyde, the disodium salt of o-thiobenzoic acid, the disodium salt of pyrocatechol, disodium oxalate, sodium diethyldithiocarbonate, malonic acid, acetylacetone and 8-hydroxy-1,2,3,4-tetrahydroquinoline. The compositions may also contain a polymerization accelerator, e.g. an amine, an organic sulphimide, succinimide, phthalimide or formamide. Other optional components include polymerization inhibitors, thickeners, plasticizers, dyes, adhesive agents and thixotropic agents; polyethylene powder is used in one of the examples.