Multi-functional alpha-alkoxyalkyl acrylate and methacrylate ester compositions and reworkable polymers formed therefrom
Adhesive compositions are disclosed which include acrylates, their polymers, and free radical initiators. The compositions include a multi-functional alpha-alkoxyalkyl (meth)acrylate compound and a free radical initiator. The multi-functional alpha-alkoxyalkyl (meth)acrylate compound is the reaction product of: (a) a (meth)acrylic acid or a (meth)acrylate ester having a free carboxylic acid group; and (b) a compound including two or more 1-alkenyl ether groups and free of acetal and ketal groups, or a compound free of acetal and ketal groups and including one or more 1-alkenyl ether groups and a (meth)acrylate group. The compositions are easier and less expensive to prepare than conventional acrylate compositions and degrade when contacted with an acid medium or when heated. The compositions are useful in a wide range of applications and are compatible with conventional adhesive additives.
1. A curable composition, comprising: (i) a multi-functional alpha-alkoxyalkyl (meth)acrylate compound comprising an ester acetal or ester ketal and free of conventional acetal or ketal groups; and (ii) a free radical initiator, said composition being degradable once cured.
2. The curable composition of claim 1 , wherein said multi-functional alpha-alkoxyalkyl (meth)acrylate compound is the reaction product of: (a) a (meth)acrylic acid or a (meth)acrylate ester having a free carboxylic acid group; and (b) a compound including two or more 1-alkenyl ether groups and being free of conventional acetal and ketal groups, or a compound free of conventional acetal and ketal groups and including one or more 1-alkenyl ether groups and a (meth)acrylate group.
3. The curable composition of claim 1 , wherein said multi-functional alpha-alkoxyalkyl (meth)acrylate compound is the reaction product of: (a) a multi-functional carboxylic acid; and (b) a compound free of acetal and ketal groups and including one or more 1-alkenyl ether groups and a (meth)acrylate group.
4. The curable composition of claim 1 , wherein said multi-functional alpha-alkoxyalkyl (meth)acrylate compound is present in an amount of about 5% to about 99% by weight of said composition.
5. The curable composition of claim 1 , wherein said multi-functional alpha-alkoxyalkyl (meth)acrylate compound has a functionality of two or greater.
6. The curable composition of claim 2 , wherein said compound having two or more 1-alkenyl ether groups present is selected from the group consisting of 1-ethenyl ether, 1-propenyl ether, 1-butenyl ether and 3,4 dihydropyranyl compounds.
7. The curable composition of claim 2 , wherein said compound having two or more 1-alkenyl ether groups present is selected from the group consisting of diethyleneglycol divinyl ether, tetraethyleneglycol divinyl ether, butanediol divinyl ether, cyclohexanedimethanol divinyl ether, polytetrahydrofuran divinyl ether, polytetrahydrofuran divinyl ether, 1,3-benzenedicarboxylic acid bis[4-(ethenyloxy)butyl]ester, bis[4-(vinyloxy)butyl]adipate, tris[4-vinyloxy)butyl]trimellitate, 1,4-di(1′propenoxy)butane, 1,6-di(1′propenoxy)hexane, 1,10-di(1′-propenoxy)decane, triethyleneglycol dipropenyl ether, trimethylolpropane tripropenyl ether, sorbitol hexapropenyl ether, pentaerythritol tetrapropenyl ether, 1,2,3-tri(1′-propenoxy)propane, 1,4-di(1, -butenoxy)butane, 1,6-di(1′-butenoxy)hexane, 1,10-di(1′butenoxy)decane, 1(1-butenoxy)-4-vinyloxybutane, 2-(3,4-dihydropyranyl)methyl 3,4-dihydropyran-2-carboxylate and combinations thereof.
8. The curable composition of claim 1 , wherein said free radical initiator is selected from the group consisting of cumene hydroperoxide, methylethyl ketone hydroperoxide, t-butyl hydroperoxide, t-butyl perbenzoate, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, pinene hydroperoxide, benzophenone, substituted benzophenone, acetophenone, substituted acetophenone, benzoin, alkyl esters of benzoin, xanthone, substituted xanthone, diethoxy-acetophenone, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, diethoxyxanthone, chloro-thio-xanthone, azo-bisisobutyronitrile, N-methyl diethanol-amine-benzophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone, camphoroquinone peroxyester, 9-fluorene carboxylic acid peroxyester and combinations thereof.
9. The curable composition of claim 1 , wherein said composition is capable of being cured by a mechanism selected from the group consisting of ultraviolet light, visible light, heat, redox and combinations thereof.
10. The curable composition of claim 1 , further comprising one or more compounds selected from the group consisting of accelerators, stabilizers, inhibitors, chelating agents, thickeners, plasticizers, fillers, elastomers, thermoplastics, and comonomers.