GB1106449A - 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.