Butadiene toughened adhesive composition

Claim 2

An adhesive composition characterized by comprising, (i) at least one polymerizable acrylate ester monomer; (ii) at least one butadiene-styrene block copolymer rubber soluble in the monomer of (i); (iii) at least one adhesion promoter; (iv) a free radical catalyst system; and . (v) an activator.

Claim 3

The adhesive composition of Claim 1, characterized in that the polymerizable acrylate ester monomer is an alkyl acrylate, cycloalkyl acrylate, alkyl methacrylate, cycloalkyl acrylate, alkyl methacrylate, cycloalkyl methacrylate, alkoxy acrylate, alkoxy methacrylate, alkylene diacrylate or alkylene dimethacrylate.

Claim 4

The composition of Claim 2, characterized by one or more of the following features: (a) the polymerizable acrylate ester monomer is a mixture of mono- and poly-functional acrylates in the amounts of about 90-60% to about 1-40%, respectively; and (b) the monofunctional polymerizable ester >monomers (i) can be represented by the formula: wherein R 1 is H, CH 3 , or lower alkyl, R 2 is H, alkyl, cycloalkyl alkoxy or alkylene group; (ii) or is methyl methacrylate, lauryl.methacrylate, tetrahydrofurfuryl methacrylate, isobornyl methacrylate, hydroxyethyl or hydroxypropyl methacrylate, cyclohexyl methacrylate, 2-ethyl hexyl methacrylate or ethyl methacrylate, or n-butyl iso-butyl or t-butyl methacrylate.

Claim 5

The adhesive composition of Claim 2 or 3, characterized in that the polyfunctional polymerizable acrylate ester may be represented by the formula: wherein R 3 is H, C 1-4 alkyl or hydroxyalkyl or R 5 OCH 2 -; R6is H, halogen or C 1-4 alkyl; R is H, OH or R50-; R is CH 2 =CR 6 C=O-; m is an integer, preferably 1 to 8; k is an integer, preferably 1 to 20; and p is 0 or 1.

Claim 6

The adhesive composition of Claim 4, characterized in that polyfunctional polymerizable acrylate ester is a glycol dimethacrylate or diacrylate, preferably polyethylene glycol dimethacrylate or butylene glycol dimethacrylate.

Claim 7

The composition of Claim 1, characterized in that the polymerizable acrylate ester monomers may be represented by the formula: wherein R 8 is selected from the class consisting of hydrogen, chlorine, and methyl and ethyl radicals; R 7 is a bivalent organic radical selected from the group consisting of lower alkylene of 1-8 carbon atoms, phenylene, and naphthylene; W is a polyisocyanate radical; E is an aromatic, heterocyclic or cycloaliphatic polyol or polyamine radical, a diol of a cycloaliphatic compound; d is either 1 or 0; i is 0 when d is 0, and otherwise equal to one less than the number of reactive hydrogen atoms of E; wherein Z is a (i) polymeric or copolymeric grafted alkylene ether polyol radical or (ii) polymeric or copolymeric methylene ether polyol radical; z is an integer equal to the valency of Z; wherein an asterisk indicates a urethane (-NH-CO-0-) or ureide (-NH-CO-NH-) linkage; Z may also be a polymeric or copolymer methylene ether polyol radical; or wherein X is -0- or -R 9 N-; R 9 is selected from the group consisting of H or lower alkyls of 1 through 7 carbon atoms; A is CH 2 =CR 10 .CO.O-; R 10 is H, or CH 3 ; n is an integer from 2 to 6 inclusive; and B is a polyvalent substituted or unsubstituted alkyl, alkenyl, cycloalkyl, aryl, aralkyl, alkyloxy-alkylene, aryloxy-arylene or heterocyclic radical .

Claim 8

The composition of Claim 1, characterized in that the polymerizable acrylate ester monomer may be . represented by the formula of: wherein R 11 is H, CH 3 , C 2 H 5 or C 1 ; R12 is a C 2-20 alkylene, alkenylene or cycloalkylene radical or a C 6-40 arylene, alkarylene, aralkarylene, alkyloxyalkylene or aryloxyarylene radical which may be substituted by 1-4 chlorine atoms or by 1-3 amino or mono- or di-C 1-3 alkylamino or C 1-3 alkoxy groups; R 13 is one of the following less one hydrogen atoms: (a) a C l-8 hydroxy alkyl or aminoalkyl group, (b) a C 1-6 alkylamino-C 1-8 alkyl group; or (c) a hydroxphenyl, an aminophenyl, a hydroxynaphthyl or an aminonaphthyl group which may be further substituted by an alkyl, alkylamino or dialkylamino group, each alkyl group in this subpart (c) containing up to about 3 carbon atoms.

Claim 9

The adhesive composition of Claim 7, characterized in that polymerizable monofunctional acrylate ester either has the formula: VI. or VII. where PR represents a propylene triol oligomer residue.

Claim 10

The adhesive composition of any preceeding claim, characterized by one or more of the following features: (a) the butadiene-styrene block copolymer rubber is present in the amounts of about 5 to about 80% by weight of the composition; (b) the butadiene-styrene block copolymer rubber is present in the amounts of about 25 to about 40%; (c) the butadiene-styrene block copolymer rubber contains a functional group at one or both ends or within a segment of the block.; and wherein the functional group preferably is selected from the group consisting of vinyl, epoxy, carboxy, and mercapto groups; (d) the adhesion promoter is acrylic acid, methacrylic acid, or a silane; and, (e) the free radical catalyst system comprises a free radical initiator and a free radical accelerator, and wherein the free radical initiator preferably is selected from the group consisting of: (i) organic peroxides, hydroperoxides, peresters, or peracids, more preferably, t-butyl perbenzoate, cumene hydroperoxide, a sulfimide or a tertiary amine, in particular 3-oxo-2,3-dihydrobenz[d]isothiazole-I, 1-dioxide or N,N-dimethyl-paratoluidine, or an aldehyde-amine . condensation product, in particular butyraldehyde-aniline, if desired optionally containing: (i) an inhibitor in the amount of about 0.1 to about 1% by weight, selected from the group consisting of hydroquinones, benzoquinones, naphthoquinones, phenanthraquinones, anthraquinones and a substituted compound of any of the foregoing, or 2,6-di-tert-butyl-4-methyl phenol, (ii) a chelator in the amount of about 0.1 to about 1% by weight, preferably ethylenediaminetetra acetic acid, or its sodium salt, 2,2-ethylene-bis-nitril methylidyne dipyridine, or a Beta-diketone.

Claim 11

The adhesive composition of Claim 9, characterized in that free radical initiator (a) (i) is of the photoinitiator-type, (ii) is present in concentrations from about 0.1% to about 10% by weight, and (iii) is selected from acetophenones, benzophenones, and 1- and 2- acetonaphthones, or (b) is selected from (i) C l to C 6 alkyl diones, (ii) metal carbonyls of the formula M x (CO) y wherein M is a metal atom, x is 1 or 2, and y is an integer determined by the total valence of the metal atoms; and ' (iii) carbonyl compounds of the general formula R 14 (CO)R 15 wherein R 14 is R 15 or hydrogen, or R 14 and R 15 taken together with the carbonyl group form an aromatic or heterocyclic ketone containing up to about 16 carbon atoms.

Claim 12

The adhesive composition of any preceeding claim, characterized by one or more of the following features: (a) the composition contains a cross-linking agent, preferably a dimethacrylate compound; (b) the butadiene-styrene block copolymer has the structure (ABA)n, wherein A represents a . polystyrene chain, B represents a polybutadiene chain, and n is an integer greater than or equal to one (1); (c) the butadiene-styrene block copolymer has the structure (AB)n, wherein A represents a polystyrene chain, B represents a polybutadiene chain, and n is an integer greater than or equal to one (1); and, (d) the butadiene-styrene block copolymer has the structure (A)n(B)m wherein A represents a polystyrene chain, B represents a polybutadiene chain, and n and m are integers greater than or equal to one (1).