Acrylate-containing compositions and their polymerization

Abstract

Polymerizable compositions comprise (a) a compound containing both (i) at least one acryloyloxy or methacryloyloxy group, (ii) at least one allyl, methallyl, or 1-propenyl group attached directly to a carbon atom which forms part of an aromatic nucleus or to an oxygen atom or an oxycarbonyl group which are in turn directly attached to such a carbon atom, the total of the said groups (i) and (ii) being at least three, and (b) a compound containing at least two mercaptan groups directly attached to aliphatic carbon atoms, in a proportion as to supply at least 0.8 such mercaptan group per allyl, methallyl or 1-propenyl group in (a) but less than 1.0 such mercaptan group in (a) per acryloyl, methacryloyl, allyl, methallyl, or 1-propenyl group. Examples of (a) are 2,2-bis(3-allyl-4-(methacryloyloxy)phenyl)propane, bis(3-methallyl-4-(methacryloyloxy)phenyl)methane, 2,2-bis(3-allyl-4-(3-(methacryloyloxy)-2-hydroxypropoxy)phenyl)propane, 2,6-dimethallylphenyl acrylate, 1-(allyloxycarbonyl)-2,4- and 2,5-bis(3-(methacryloyloxy)-2-hydroxypropoxycarbonyl)benzene, and benzophenone-3,4,3',4'-tetracarboxylic acid X,X'-diallyl esters Y,Y'-bis(3-(methacryloyloxy)-2-hydroxypropyl) esters. Examples of (b) are pentaerythritol tetrathioglycollate, trimethylolpropane trithioglycollate, and 3,6-dioxa-1,8-dimercapto-octane. The compositions may be polymerized by means of actinic irradiation in the presence of an added or "built-in" photosensitizer or by the action of a free-radical catalyst. Compositions containing both a photosensitizing agent and a heat-activated free-radical catalyst may be subjected to a two-stage process, comprising brief exposure to actinic radiation followed by, when desired, heating. They are useful in the production of surface coatings, adhesive bonds, and of reinforced composites.

Dependencies are inferred from the claim text.