ES334593A1 - Improvements in or relating to adhesives or sealing compounds - Google Patents

Abstract

Anaerobic adhesives and sealing compounds comprise at least one acrylate or methacrylate ester of a monohydric cycloaliphatic alcohol and 0.1 to 20% by weight, based on the total mixture, of an organic peroxide or hydroperoxide. In a modification, the (meth)acrylate ester may have one or two -CH2- groups in the cycloaliphatic ring replaced by oxygen atoms. Suitable esters include those of cyclopentanol, methylcyclopentanol, cyclohexanol, methylcyclohexanol, methylolcyclopentane, methylolcyclohexane, borneol, tetrahydrofurfuryl alcohol and 1,3-dioxa-2,2-dimethyl-4-methylolcyclopentane. The composition may also include a minor amount, e.g. 2 to 20% by weight, of a copolymerizable compound, e.g. acrylates or methacrylates of other monohydric alcohols such as the butyl and 2-ethyl-hexyl esters, and maleate and fumarate esters an unsaturated polyester may also be included. Other optional components include stabilizers, e.g. hydroquinone, di-t-butylhydroquinone and quinone accelerators for use with the peroxy-compounds, e.g. tertiary amines and mercaptans thickeners, e.g. polymethyl or polyethyl methacrylate plasticizers dyestuffs fillers, e.g. silica, calcium silicate, bentonite, calcium carbonate and titanium dioxide. Suitable peroxy compounds include t-butyl, cumene, methyl ethyl ketone and diisopropylbenzene hydroperoxides, and methyl ethyl ketone peroxide, t-butylperbenzoate and 2,2-bis-(t-butylperoxy)-butane. The compositions are suitable for bonding together various surfaces, e.g. glass, plastics, porcelain and metals the surfaces may be pretreated with metal salt accelerators for the anaerobic composition, e.g. copper or cobalt naphthenate. Curing can be accelerated by heating.ALSO:Tetrahydrofurfuryl methacrylate is prepared by heating methyl methacrylate and tetra-hydrofurfuryl alcohol in the presence of hydroquinone (polymerization inhibitor) and p-toluenesulphonic acid, the methanol of reaction being removed by distillation as an azeotropic mixture with methyl methacrylate. The methacrylate esters of cyclohexanol and 1,3-dioxa-2,2-dimethyl-4 -methylolcyclopentane are prepared in a similar manner.