Two-part silane-modified polymer / free-radically curable adhesive system

Abstract

Two-part silane-modified polymer / free-radically curable adhesive systems exhibiting improved strength and percent elongation are provided.

Description

[0001] background Technical Field

[0002] A two-part silane-modified polymer / free radical curable adhesive system is provided, exhibiting improved strength and elongation percentage. Background Technology

[0003] Adhesives containing silane-modified polymers (or "SMPs") are commonly used in elastic bonding applications where high elongation and tensile strength are required. However, commercially available SMP adhesives are typically limited to tensile strengths of less than 3 MPa and elongation of less than 300%.

[0004] In some cases, commercial applications require higher tensile strength. For example 5-8 MPa) and greater elongation ( example like (>300%). SMP adhesives typically also require surface pretreatment (e.g., removal of oily contaminants) or treatment (e.g., grinding to promote good interfacial adhesion) to ensure the formation of a durable bond.

[0005] In the past, to achieve higher tensile strength, elongation percentage was typically sacrificed, and (meth)acrylates were chosen as the primary raw materials. Right now Acrylic adhesives are reactive acrylic adhesives that cure through the free radical polymerization of methyl methacrylate (Mmethacrylate). However, these acrylic adhesives have certain drawbacks. Commercially important acrylic adhesives tend to have an unpleasant odor, especially those made from methyl methacrylate. Mmethacrylate-based acrylic adhesives also have a low flash point (approximately 59°F). A low flash point is a problem during the storage and transportation of the adhesive. If the flash point is 141°F or lower, the U.S. Department of Transportation classifies the product as "flammable" and requires labeling and special storage and transportation conditions.

[0006] U.S. Patent No. 6,562,181 (Righettini) aims to provide a solution to the problem presented in the preceding paragraph by describing an adhesive composition comprising: (a) a trifunctional olefinic first monomer comprising an olefinic group having at least three functional groups each directly bonded to an unsaturated carbon atom of said olefinic group; (b) an olefinic second monomer that is copolymerizable with the first monomer; (c) a redox initiator system; and (d) a reactive diluent, wherein the composition is liquid at room temperature, is 100% reactive, substantially free of volatile organic solvents, and is curable at room temperature.

[0007] Recently, U.S. Patent No. 9,371,470 (Burns) describes and claims a two-part curable composition comprising: (a) a first part comprising a cyanoacrylate component and a peroxide catalyst; and (b) a second part comprising a radical-curable component and a transition metal. When mixed together, the peroxide catalyst initiates the curing of the radical-curable component, and the transition metal initiates the curing of the cyanoacrylate component.

[0008] Additionally, U.S. Patent No. 8,809,479 (Huang) relates to and claims a moisture-curable resin composition comprising: (a) a moisture-curable polymer having at least one hydrolyzable silyl group, wherein the polymer is represented by general formula (3):

[0009]

[0010] Where R 6 Each occurrence is an independent monovalent or polyvalent organic polymer fragment having a number-average molecular weight of 500 to 25,000 g / mol and derived from a hydroxyl-terminated polypropylene oxide with a terminal olefinic unsaturation degree of less than 0.02 mEq / g polyol and containing at least one urethane functional group; R 7 Each time it appears, it is independently a divalent alkylene group containing 1 to 6 carbon atoms; A 1 Each time it appears, it is divalent oxygen (—O—); A 2 Each occurrence is a structure—NR 8 — the substituted nitrogen, where R 8 It is hydrogen; X 1 Each occurrence is independently assigned the value R. 9 O—, where each R 9 Independently hydrogen or an alkyl group containing 1 to 4 carbon atoms; X 2 and X 3 Each time it appears, it is selected independently from R. 9 O—and R 10 , where each R 9 Independently selected from hydrogen or alkyl groups containing 1 to 4 carbon atoms, and each R 10 (a) Alkyl groups containing 1 to 4 carbon atoms; and the subscripts e and f are independent integers each time they appear, where e is 1 and f is 1 to 6; (b) Reactive modifiers of the following general formula:

[0011] G 2 [-SiR 4 c (OR 5 ) 3-c ] d

[0012] Among them G 2 Selected from monovalent or divalent straight-chain hydrocarbon groups containing 3 to 16 carbon atoms; R 4 Each time it appears, it is a monovalent alkyl group containing 1 to 4 carbon atoms; R 5 Each occurrence is a monovalent alkyl group containing 1 to 4 carbon atoms; c and d are independent integers each time they occur, where: c is 0 or 1; d is 1 or 2, provided that (i) when G 2 When containing heteroatoms, G 2 The terminal atom is a carbon atom; and (ii) when silicon atoms are attached to G 2 At that time, silicon atoms are covalently bonded to G 2 The terminal carbon; and (c) at least one catalyst for catalyzing the reaction between the moisture-curable polymer (a) and the reactive modifier (b) under moisture-curing conditions, the catalyst being a compound selected from organo-dibutyltin, zirconium complexes, aluminum chelates, titanium chelates, organozinc, organocobalt, organoiron, organonitrile, organobismuth, and amines; and wherein, based on the total weight of components (a), (b), and (c), component (b) is present in an amount of 20% to 40% by weight, and component (c) is present in an amount of 0.1% to 3% by weight.

[0013] U.S. Patent Application Publication No. 2015 / 0027634 (Kohl) relates to a moisture-curable two-component composition of component A and component B, wherein component A contains at least one polyoxyethylene, polyolefin and / or polyacrylate prepolymer having at least one hydrolyzable silane group and at least one solid inert additive selected from hydrocarbons, polyesters or polyamides, and component B contains at least one crosslinking compound for the prepolymer, and both the two-component composition and component A have hot melt adhesive properties.

[0014] SMP / epoxy hybrid adhesives are known and commercially available. For example, Manus reports that its MANUS-BOND FLEX-WELD has a tensile strength of 5.5 MPa and an elongation percentage of less than 100%. While the tensile strength is suitable, the elongation percentage is not ideal for many commercial applications.

[0015] Despite the current state of the technology, it will be desirable and necessary to provide adhesive systems with features not found in conventional adhesives, such as improved bond strength and increased elongation. Summary of the Invention

[0016] In one aspect, a two-part adhesive composition is provided, the two-part adhesive composition comprising:

[0017] (a) Part A composition, said Part A composition comprising:

[0018] (i) (meth)acrylate functionalized components; and

[0019] (ii) Block copolymer components; and

[0020] (b) Part B composition, said part B composition comprising:

[0021] (i) Alkoxysilane functionalized components or acylsilane functionalized components.

[0022] Part A of the composition or part B of the composition contains an oxidizing agent, and part A of the composition or part B of the composition contains at least one, preferably both, of a reducing agent and a transition metal, provided that part A of the composition and part B of the composition do not each contain an oxidizing agent, a reducing agent and / or a transition metal.

[0023] Compositions that can cure at room temperature because portions of composition A and composition B do not interact before being mixed provide improved bond strength and elongation compared to conventional adhesive compositions.

[0024] More specifically, in some cases, the two-part curable compositions of the present invention have exhibited tensile strengths of about 4 to 10 MPa (e.g., about 5 to 8 MPa) and elongation percentages greater than 400, or even close to 500. The combination of high tensile strength and elongation percentages observed is surprisingly better than either of the individual curable compositions.

[0025] On the other hand, a two-part adhesive composition is provided, the two-part adhesive composition comprising:

[0026] (a) Part A composition, said Part A composition comprising:

[0027] (i) A (meth)acrylate functionalized component, at least a portion of which comprises an alkyl (meth)acrylate and a monofunctional (meth)acrylate component, wherein the monofunctional (meth)acrylate component is selected from one or more of isobornyl (meth)acrylate, lauryl (meth)acrylate, and / or ethylhexyl (meth)acrylate; and

[0028] (ii) a rubber toughening component comprising one or more of the following: (meth)acrylate-terminated polybutadiene, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenated styrene-containing copolymer, core-shell rubber, and combinations thereof, which are in liquid form at room temperature; and

[0029] (iii) An optional reactive acid component, said reactive acid component comprising one or more phosphate esters of (meth)acrylic acid and / or hydroxyethyl methacrylate; and

[0030] (b) Part B composition, said part B composition comprising:

[0031] (i) An alkoxysilane functionalized component or an acyloxysilane functionalized component, wherein a portion of composition A or a portion of composition B contains an oxidizing agent, and a portion of composition A or a portion of composition B contains at least one, preferably both, of a reducing agent and a transition metal, provided that a portion of composition A and a portion of composition B do not each contain an oxidizing agent, a reducing agent and / or a transition metal.

[0032] In another aspect, a two-part adhesive composition is provided, the two-part adhesive composition comprising:

[0033] (a) Part A composition, said Part A composition comprising:

[0034] (i) Methacrylate functionalized components;

[0035] (ii) Methacrylate-functionalized carbamates; and

[0036] (iii) Block copolymer components; and

[0037] (b) Part B composition, said part B composition comprising:

[0038] (i) Alkoxysilane functionalized components or acylsilane functionalized components.

[0039] Part A of the composition or part B of the composition contains an oxidizing agent, and part A of the composition or part B of the composition contains at least one, preferably both, of a reducing agent and a transition metal, provided that part A of the composition and part B of the composition do not each contain an oxidizing agent, a reducing agent and / or a transition metal.

[0040] Here, upon dispensing, the two-part adhesive composition is capable of curing within a fixation time of approximately 15 to approximately 45 minutes on an aluminum substrate with a 1 mm gap. Furthermore, upon curing, the two-part adhesive composition exhibits at least one of a tensile strength greater than 2.5 MPa on the aluminum substrate and an elongation percentage greater than 100%. Detailed Implementation

[0041] As described above, in a first aspect, a two-part adhesive composition is provided, the two-part adhesive composition comprising:

[0042] (a) Part A composition, said Part A composition comprising:

[0043] (i) (meth)acrylate functionalized components; and

[0044] (ii) Block copolymer components; and

[0045] (b) Part B composition, said part B composition comprising:

[0046] (i) Alkoxysilane functionalized components or acylsilane functionalized components.

[0047] Part A of the composition or part B of the composition contains an oxidizing agent, and part A of the composition or part B of the composition contains at least one, preferably both, of a reducing agent and a transition metal, provided that part A of the composition and part B of the composition do not each contain an oxidizing agent, a reducing agent and / or a transition metal.

[0048] In a second aspect, a two-part adhesive composition is provided, the two-part adhesive composition comprising:

[0049] (a) Part A composition, said Part A composition comprising:

[0050] (i) A (meth)acrylate functionalized component, at least a portion of which comprises an alkyl (meth)acrylate and a monofunctional (meth)acrylate component, wherein the monofunctional (meth)acrylate component is selected from one or more of isobornyl (meth)acrylate, lauryl (meth)acrylate, and / or ethylhexyl (meth)acrylate; and

[0051] (ii) a rubber toughening component comprising one or more of the following: (meth)acrylate-terminated polybutadiene, styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, hydrogenated styrene-containing copolymers, core-shell rubbers, and combinations thereof, which are in liquid form at room temperature; and

[0052] (iii) An optional reactive acid component, said reactive acid component comprising one or more phosphate esters of (meth)acrylic acid and / or hydroxyethyl methacrylate; and

[0053] (b) Part B composition, said part B composition comprising:

[0054] (i) An alkoxysilane functionalized component or an acyloxysilane functionalized component, wherein a portion of composition A or a portion of composition B contains an oxidizing agent, and a portion of composition A or a portion of composition B contains at least one, preferably both, of a reducing agent and a transition metal, provided that a portion of composition A and a portion of composition B do not each contain an oxidizing agent, a reducing agent and / or a transition metal.

[0055] In a third aspect, a two-part adhesive composition is provided, the two-part adhesive composition comprising:

[0056] (a) Part A composition, said Part A composition comprising:

[0057] (i) Methacrylate functionalized components;

[0058] (ii) Methacrylate-functionalized carbamates; and

[0059] (iii) Block copolymer components; and

[0060] (b) Part B composition, said part B composition comprising:

[0061] (i) Alkoxysilane functionalized components or acylsilane functionalized components.

[0062] Part A of the composition or part B of the composition contains an oxidizing agent, and part A of the composition or part B of the composition contains at least one, preferably both, of a reducing agent and a transition metal, provided that part A of the composition and part B of the composition do not each contain an oxidizing agent, a reducing agent and / or a transition metal.

[0063] In this third aspect, when dispensed, the two-part adhesive composition is capable of curing on an aluminum substrate with a 1 mm gap within a curing time of approximately 15 to approximately 45 minutes. Furthermore, upon curing, the two-part adhesive composition exhibits at least one of a tensile strength greater than 2.5 MPa on the aluminum substrate and an elongation percentage greater than 100%.

[0064] Partial Composition A

[0065] According to a first aspect, the (meth)acrylate functionalized component (i) of a portion of composition A comprises an alkyl (meth)acrylate and / or a monofunctional (meth)acrylate component. According to a second aspect, the (meth)acrylate functionalized component (i) of a portion of composition A may comprise an alkyl (meth)acrylate and one or more of isobornyl (meth)acrylate, lauryl (meth)acrylate, and / or ethylhexyl (meth)acrylate.

[0066] Alkyl methacrylates can be selected from many methacrylates, some of which are aromatic, others aliphatic, and still others alicyclic. Examples of such alkyl methacrylates include difunctional or trifunctional methacrylates, such as polyethylene glycol dimethacrylate, tetrahydrofuran (meth)acrylate and tetrahydrofuran dimethacrylate, hydroxypropyl methacrylate (“HPMA”), hexanediol dimethacrylate, trimethylolpropane trimethacrylate (“TMPTMA”), diethylene glycol dimethacrylate, triethylene glycol dimethacrylate (“TRIEGMA”), benzyl methacrylate, tetraethylene glycol dimethacrylate, dipropylene glycol dimethacrylate, di-(1,5-pentylene glycol) dimethacrylate, tetraethylene diethylene glycol dimethacrylate. diacrylate), diglyceride tetramethyl acrylate, dimethacrylate tetramethylene acrylate, dimethacrylate ethylene acrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, and bisphenol A mono(meth)acrylate and bisphenol A di(meth)acrylate (such as ethoxylated bisphenol A (meth)acrylate (“EBIPMA”)), bisphenol F mono(meth)acrylate and bisphenol F di(meth)acrylate (such as ethoxylated bisphenol F (meth)acrylate), (meth)acrylate functionalized carbamates, and (meth)acrylate hydroxyalkyl esters, etc.

[0067] Hydroxyalkyl methacrylates include 2-hydroxyethyl methacrylate, phenoxyethyl methacrylate, N-vinylcaprolactam, N,N-dimethylacrylamide, 2-(2-ethoxyethoxy)ethyl acrylate, caprolactone acrylate, polypropylene glycol monomethacrylate, 1,3-butanediol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol di(meth)acrylate, tricyclodecanediethanol di(meth)acrylate, tripropylene glycol di(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, tri(2-hydroxyethyl)isocyanurate tri(meth)acrylate, and combinations thereof.

[0068] In addition, 1,4-butanediol dimethacrylate, 1,6-hexanediol di(meth)acrylate, tricyclodecanediethanol di(meth)acrylate, tripropylene glycol diacrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane triacrylate, and tri(2-hydroxyethyl)isocyanurate triacrylate can be used.

[0069] Based on the total weight of the (meth)acrylate functionalized components, the (meth)acrylate alkyl esters and / or monofunctional (meth)acrylate components should be used in amounts of about 10% by weight to about 50% by weight (e.g., about 15% by weight to 30% by weight).

[0070] The block copolymer component (ii) of the composition in part A of the first and second aspects may in particular comprise one or more of the following: (meth)acrylate-terminated polybutadiene, styrene-containing block copolymers, core-shell rubbers, and combinations thereof, which are in liquid form at room temperature. The styrene-containing block copolymers may be selected from styrene-butadiene-styrene (“SBS”), styrene-isoprene-styrene (“SIS”), hydrogenated styrene-containing copolymers (“SEBS”), and combinations thereof. The weight-average molecular weight of the SBS block copolymer and the SIS block copolymer should be at least about 100,000 Mw, such as about 100,000 to about 500,000 Mw, and preferably about 100,000 to about 200,000 Mw.

[0071] Commercially available examples of such block copolymers are available under the trade name KRATON (e.g., KRATON D1114, D1115, and D1155) from Kraton Corporation, Houston, TX. The block copolymer component can be used in an amount of about 5% to about 25% by weight, based on the total amount of portion A and portion B of the composition.

[0072] A commercially available example of a core-shell rubber is CLEARSTRENGTH XT100, which is available from Arkema Inc., Cary, NC and described as a methyl methacrylate-butadiene-styrene core-shell toughening agent. It is compatible with a variety of monomers and can be easily dispersed in most liquid resin systems, exhibiting limited effect on their viscosity while providing toughening effects over a wide operating temperature range.

[0073] The (meth)acrylate-functionalized carbamate of part A of the third aspect may include a number of materials.

[0074] For example, (meth)acrylate-functionalized urethanes can be in the form of multifunctional (e.g., difunctional or trifunctional) urethane acrylate oligomers, and more preferably aliphatic polyether urethane acrylates. A suitable example of a (meth)acrylate-functionalized urethane is BR-582E8 (commercially available from Dymax Corporation, Torrington, CT), which is described as an aliphatic urethane acrylate oligomer with a polyether backbone. The manufacturer states that Bomar BR-582E8 offers a balance of toughness and flexibility. Dymax recommends this product for use in single-coat flexible coatings on both metal and plastic substrates, and it is an excellent choice for impact and flexural coatings, thus also exhibiting abrasion resistance, flexibility, gloss, hydrolytic stability, weather resistance, and non-yellowing. Dymax reports that this product has a DMA-based Tg of 23°C and a nominal viscosity of 60,000 cP at 50°C, and bonds to a variety of substrates except high-density polyethylene. BR-582E8 is listed in the table below.

[0075] Dymax also makes a range of other (meth)acrylate-functionalized urethanes commercially available, having a functionality between about 1 and about 3, and exhibiting an elongation percentage greater than about 50. One such (meth)acrylate-functionalized urethane from Dymax is a trifunctional urethane acrylate oligomer, more specifically known as BR-990, an aliphatic polyether urethane triacrylate.

[0076] Among (meth)acrylate-functionalized urethanes are those based on polyesters or polyethers, which react with aromatic, aliphatic, or alicyclic diisocyanates and are capped with hydroxyacrylates.

[0077] For example, bifunctional urethane acrylate oligomers, such as polyesters of adipic acid and diethylene glycol with isophorone diisocyanate as the terminal end of 2-hydroxyethyl acrylate (CAS 72121-94-9); polypropylene glycol with toluene-2,6-diisocyanate as the terminal end of 2-hydroxyethyl acrylate (CAS 37302-70-8); polyesters of adipic acid and diethylene glycol with 4,4'-methylenebis(cyclohexyl isocyanate) as the terminal end of 2-hydroxyethyl acrylate (CAS 69011-33-2); and polyesters of adipic acid, 1,2-ethylene glycol, and 1,2-propylene glycol with toluene-2,4-diisocyanate as the terminal end of 2-hydroxyethyl acrylate (CAS 72121-94-9); ... 69011-31-0); polyesters of adipic acid, 1,2-ethylene glycol and 1,2-propylene glycol with 4,4'-methylenebis(cyclohexyl isocyanate) as the terminal end, capped with 2-hydroxyethyl acrylate (CAS69011-32-1); and polytetramethylene glycol ethers with 4,4'-methylenebis(cyclohexyl isocyanate) as the terminal end, capped with 2-hydroxyethyl acrylate.

[0078] The following (meth)acrylate-functionalized urethane resins, commercially available from Dymax, are useful: BR-930D [described by the manufacturer as a flexible and weather-resistant polyether urethane acrylate with a nominal viscosity of 7700 at 60°C and a Tg (°C) of 95 according to DMA. The manufacturer advertises BR-930D as having the following characteristics for selected applications: ideal typical for 3D printing resins; high heat distortion temperature; providing good toughness and impact resistance; enhanced weather resistance and low skin irritation]; and BR 7432G130 [described by the manufacturer as a flexible and weather-resistant polyester urethane acrylate with a nominal viscosity of 80000 at 25°C and a Tg (°C) of 28 according to DMA]. The manufacturer advertises BR 7432G130 for selected applications as having the following characteristics: imparting toughness; high tensile strength; improved impact resistance; adhesion to polymer films; elasticity; and BR-3741AJ [described by the manufacturer as a flexible and weather-resistant polyether urethane acrylate with a nominal viscosity of 25,000 at 60°C and a Tg (°C) of -50 according to DMA]. The manufacturer advertises BR 3741AJ for selected applications as having the following characteristics: enhanced softness and flexibility; improved optical transparency; non-yellowing; improved adhesion; adhesion to various substrates; exhibiting hydrolytic stability; oil and chemical resistance; and being an ideal typical PSA.

[0079] Other examples of such (meth)acrylate-functionalized urethanes include tetramethylene glycol urethane acrylate oligomers and propylene glycol urethane acrylate oligomers.

[0080] Other (meth)acrylate-functionalized urethanes are monofunctional urethane acrylate oligomers, such as polypropylene with 4,4'-methylenebis(cyclohexyl isocyanate) as the end terminator, which is capped with 2-hydroxyethyl acrylate and 1-dodosanol.

[0081] These also include bifunctional urethane methacrylate oligomers, such as polytetramethylene glycol ethers capped with 2-hydroxyethyl methacrylate and terminated with toluene-2,4-diisocyanate; polytetramethylene glycol ethers capped with 2-hydroxyethyl methacrylate and terminated with isophorone diisocyanate; polytetramethylene glycol ethers capped with 2-hydroxyethyl methacrylate and terminated with 4,4'-methylenebis(cyclohexyl isocyanate); and polypropylene glycol capped with 2-hydroxyethyl methacrylate and terminated with toluene-2,4-diisocyanate.

[0082] Other suitable (meth)acrylate-functionalized carbamates include those disclosed in Baccei's U.S. Patent Nos. 4,018,851, 4,295,909, and 4,309,526, and Lapin et al.'s U.S. Patent Nos. Re 33,211, 4,751,273, 4,775,732, 5,019,636, and 5,139,872.

[0083] Therefore, (meth)acrylate-functionalized urethanes can be selected from a variety of materials, some of which are commercially available from Dymax and are listed in the table below along with certain key characteristics:

[0084]

[0085]

[0086]

[0087]

[0088] As an example, BR-345 (meth)acrylate-functionalized carbamate can be prepared according to the following reaction scheme:

[0089]

[0090] Another example of a useful (meth)acrylate-functionalized carbamate is a block resin represented as a polymer of 4,4-(1-methylethylidene)bicyclohexanol with 1,3-diisocyanate-based methylbenzene and tetrahydrofuran, propylene glycol monomers (CAS No. 2243075-64-9), prepared by reacting propylene glycol monomers with dicarboxylic acids to form polyester glycol, then reacting with toluene diisocyanate, and finally capping with (meth)acrylate hydroxypropyl ester.

[0091] Another example of a useful (meth)acrylate-functionalized urethane is a block resin prepared from a saturated polyester diol (such as saturated polyester diol sold under the trade name Desmophen S-1011-35) and dicyclohexylmethane-4,4'-diisocyanate (commercially available from DESMODUR W), and end-capped with 2-hydroxyethyl acrylate. This block resin is diluted with IBOA. In the examples, this block resin is referred to as Resin A.

[0092] The following resins, though not used in the examples, are very suitable: Resin B, containing a central segment of POLYMEG2000 (polytetramethylene ether diol, produced by polymerizing tetrahydrofuran to form a main chain of repeating tetramethylene units linked by ether bonds and a straight-chain diol end-capped with primary hydroxyl units) (TDI-HBPA or IPDI-HMTD linked to this central segment by urethane bonds), and end-capped with TDI-HPMA or IPDI-HEMA; Resin C, prepared from hydroxy-functionalized polyether, polyester (commercially available from KURARAY Polyol P-2010), and TDI, as well as hydroxypropyl methacrylate and isobornyl methacrylate; and Resin D, prepared from polyTHF (Mw 2000), TDI, and HBPA, hydroxypropyl methacrylate, hydroxyethyl methacrylate, and isobornyl methacrylate.

[0093] In some cases, as described in U.S. Patent No. 10,745,590, hydrophobic (meth)acrylate-functionalized urethanes may be desirable, such as those with a weight-average molecular weight (“Mw”) of 35,000 to 60,000 g / mol as determined by gel permeation chromatography (“GPC”). When Mw falls within this range, the cured product may also exhibit strong cohesion and high elongation. Preferably, the hydrophobic (meth)acrylate-functionalized urethane should have a functionality of equal to or less than 2 (meth)acrylate groups. When the functionality of the (meth)acrylate groups falls within this range, the cured product may also exhibit high elongation. These hydrophobic (meth)acrylate-functionalized urethanes should have a glass transition temperature (“Tg”) value determined by differential scanning calorimetry (“DSC”) from -60°C to 20°C.

[0094] The hydrophobic (meth)acrylate-functionalized urethane can be selected from aliphatic urethane (meth)acrylates, aromatic urethane (meth)acrylates, and mixtures thereof, such as polybutadiene-based urethane (meth)acrylates, polyisobutylene-based urethane (meth)acrylates, polyisoprene-based urethane (meth)acrylates, polybutyl rubber-based urethane (meth)acrylates, and mixtures thereof. Suitable commercially available hydrophobic urethane (meth)acrylates include UT-4462 and UV36301B90 from Nippon Gohsei; CN 9014 from Sartomer; and SUO-H8628 from SHIIN-AT&C.

[0095] Suitable (meth)acrylate-functionalized urethanes also include oligomers with a number-average molecular weight (“Mn”) of about 500 to about 100,000 as determined by GPC.

[0096] (Meth)acrylate-functionalized urethanes may also include polyurethane block copolymers having a backbone with alternating hard and soft segments and at least two ends. Each end may be capped with a vinyl ether, alkenyl ether, or (meth)acrylate group. Such polyurethane block copolymers can be represented by the following general formula:

[0097]

[0098] Where A is a hard segment, such as the reaction product of polyisocyanate with aromatic, heterocyclic or alicyclic polyols;

[0099] B is a divalent soft segment and X is a q-valent soft segment, where B and X can be divalent and polyvalent groups derived from polyether polyols, polyester polyols, or hydrogenated hydrocarbon elastomers (such as polybutadiene), respectively.

[0100] D is a vinyl ether or (meth)acrylate group, such that the vinyl ether can be derived from a hydroxyl-functionalized vinyl ether (e.g., 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, cyclohexanediol monovinyl ether, diethylene glycol monovinyl ether, 1,6-hexanediol monovinyl ether and 3-aminopropyl vinyl ether), or the vinyl ether end group can be derived from an amino-functionalized vinyl ether, in which case a vinyl ether urea-terminated polyurethane can be obtained;

[0101] p is 0-10; and

[0102] q is 2-6.

[0103] Another example of a (meth)acrylate-functionalized urethane is a (meth)acrylate-functionalized urethane having a polyurethane backbone, at least a portion of which comprises urethane bonds formed from isophorone diisocyanate. For example, such a (meth)acrylate-functionalized urethane is prepared from an alkylaneglycol (such as polypropylene glycol), isophorone diisocyanate, and a hydroxyalkyl (meth)acrylate (such as hydroxyethyl acrylate). Other examples include polyesters of adipic acid and diethylene glycol with isophorone diisocyanate as the terminal end of 2-hydroxyethyl acrylate; polytetramethylene glycol ethers with isophorone diisocyanate as the terminal end of 2-hydroxyethyl methacrylate; and hydroxyl-terminated polybutadiene with isophorone diisocyanate as the terminal end of 2-hydroxyethyl acrylate.

[0104] In this respect, based on the total weight of part A of the composition, the (meth)acrylate-functionalized carbamate should be present in an amount of about 18% by weight to about 45% by weight, such as about 20% by weight to about 40% by weight, such as about 26% by weight to about 38% by weight.

[0105] Alkyl methacrylates that can be used to prepare urethanes functionalized with methacrylates include isobornyl methacrylate, isodecanyl methacrylate, lauryl methacrylate, cyclotrimethylolpropane methyl acetal acrylate, octyldecyl acrylate, tetrahydrofurfuryl methacrylate, tridecyl methacrylate, and hydroxyalkyl methacrylate, etc.

[0106] Hydroxyalkyl methacrylates used for end-capping urethanes thus formed with (meth)acrylates include 2-hydroxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, N-vinylcaprolactam, N,N-dimethylacrylamide, 2-(2-ethoxyethoxy)ethyl acrylate, caprolactone acrylate, polypropylene glycol monomethacrylate, 1,3-butanediol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol di(meth)acrylate, tricyclodecanediethanol di(meth)acrylate, tripropylene glycol diacrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane triacrylate, tri(2-hydroxyethyl)isocyanurate triacrylate, and combinations thereof.

[0107] Composition A may also contain a reactive acid component, which may be one or more of (meth)acrylic acid and / or (meth)acrylates (such as phosphoric acid esters, phosphate acid esters), and sulfonic acids or derivatives. A preferred reactive acid component is a phosphate ester.

[0108] Suitable phosphate esters include those represented by the following formula:

[0109]

[0110] Here, R is H or CH3, and R is H or a group represented by the following structures:

[0111]

[0112] R here 1 It is H or CH3.

[0113] A particularly useful phosphate ester is 2-hydroxyethyl methacrylate (“HEMA”) phosphate, which is sold under the trade name HARCRYL and is available from Harcros Chemicals, Kansas City, KS.

[0114] If used, the reactive acid component is present in amounts of up to about 5% to 10% by weight, preferably about 0.1% to about 3% by weight.

[0115] Partial B composition

[0116] The alkoxysilane functionalized component or acyloxysilane functionalized component of part B composition may be a polymer having at least one hydrolyzable silane group, which is bonded to the polymer chain via an ether (-O-) linker or a carbonyl group, wherein the carbonyl group is bonded to a heteroatom selected from oxygen, nitrogen and sulfur, provided that at least one heteroatom is nitrogen.

[0117] For example, alkoxysilane functionalized components or acyloxysilane functionalized components can be included in polymers with the following structures:

[0118]

[0119] Where R 6 Each occurrence is independently a monovalent or polyvalent organic polymer fragment with a number-average molecular weight of 500 to 25,000 g / mol; R 7 Each occurrence is independently a divalent hydrocarbon group containing 1 to 12 carbon atoms, selected from divalent alkylene, alkenylene, arenylene, arylene, and arylalkylene, and optionally, the divalent hydrocarbon group contains at least one heteroatom selected from oxygen, nitrogen, and sulfur. 2 Each occurrence of A is independently selected from divalent oxygen (—O—), sulfur (S-), or a substituted nitrogen of the structure (-)-NR, wherein R is hydrogen, alkyl, alkenyl, arenyl, aryl, aralkyl, or R'SiXXX group, wherein when not hydrogen, each R' contains 1 to 18 carbon atoms, and A is (-)-NR when A' is oxygen or sulfur, and A' is oxygen when e is 0; each occurrence of A is independently selected from divalent oxygen (—O—), sulfur (S-), or a substituted nitrogen of the structure (-)-NR, NR(C=O)NR, NR(C=O)C, and NR(C=O)S, wherein R is hydrogen, alkyl, alkenyl, arenyl, aryl, aralkyl, or R'SiXXX group, wherein when not hydrogen, each R' contains 1 to 18 carbon atoms. A' is (-)-NR when A is oxygen or sulfur; X is independently RO each time it appears, wherein each R is independently selected from hydrogen, alkyl, alkenyl, aryl, aryl and aralkyl, wherein when not hydrogen, each R contains 1 to 18 carbon atoms and optionally contains at least one oxygen or sulfur atom; X and X' are independently selected from RO and R'' each time they appear, wherein each R is independently selected from hydrogen, alkyl, alkenyl, aryl, aryl and aralkyl, wherein when not hydrogen, each R contains 1 to 18 carbon atoms and optionally contains at least one oxygen or sulfur atom, and each R'' is independently an alkyl containing 1 to 6 carbon atoms; and e and f are independently integers each time they appear, wherein e is 0 or 1 and f is 1 to 6.

[0120] Based on the total weight of some of the B composition components, the alkoxysilane functionalized component or the acylsilane functionalized component may be present in the composition in an amount of about 30% to about 95% by weight, such as about 50% to about 90% by weight, or preferably about 60% to about 80% by weight.

[0121] Alkoxysilane-functionalized components or acylsilane-functionalized components can be prepared from polyol reactants or combinations of polyol reactants. Combinations of polyol reactants are typically used to achieve specific physical properties (such as flowability, tensile strength, modulus, and adhesion) of alkoxysilane-functionalized components or acylsilane-functionalized components. The number-average molecular weight of the polyol reactants is specifically 300 to 24,000 g / mol, more specifically 1,000 to 20,000 g / mol.

[0122] The average hydroxyl functionality of the polyol reactant mixture is specifically 1.6 to 6.0 hydroxyl groups per polyol molecule, more specifically 1.8 to 3.0 hydroxyl groups per polyol molecule, and most specifically 1.95 to 2.5 hydroxyl groups per polyol molecule.

[0123] Alkoxysilane-functionalized components or acylsilane-functionalized components can be prepared from blends of low number-average molecular weight polyol reactants and high number-average molecular weight polyol reactants. Alkoxysilane-functionalized components or acylsilane-functionalized components prepared from these polyol reactant blends exhibit high modulus after curing and at low strain, while maintaining a high percentage of elongation at break.

[0124] The number average molecular weight of low molecular weight polyols should be 300 to 2000 g / mol, such as 500 to 1200 g / mol, and preferably 800 to 1000 g / mol. The number average molecular weight of high molecular weight polyols is specifically 2000 to 24000 g / mol, more specifically 4000 to 12000 g / mol, and most specifically 8000 to 10000 g / mol. The weight ratio of low molecular weight polyol reactants to high molecular weight polyol reactants is specifically 0.01 to 3, more specifically 0.05 to 1, and most specifically 0.2 to 0.5. Representative, non-limiting examples of polyols include hydroxyl-terminated polyoxyethylenes, such as hydroxyl-terminated polypropylene oxides, hydroxyl-terminated polyethylene oxides, and hydroxyl-terminated polybutene oxides; polyalkylene triols; polycaprolactone diols and polycaprolactone triols; hydroxyl-terminated unsaturated rubbers, such as hydroxyl-terminated polybutadiene copolymers; polyester diols and polyols prepared from saturated aliphatic diacids and diols or triols, unsaturated diacids and diols or triols, saturated polyacids and diols or aromatic diacids and diols or triols; polytetramethylene diols; and other diols or triols.

[0125] These polyols can have very low levels of unsaturation and therefore high functionality. They are typically prepared using metal complex catalysts that oxidize the polymerization of olefins, resulting in polyols with low levels of terminal olefinic unsaturation. The number-average molecular weight of these polyols is specifically in the range of 500 to 24,000 g / mol, more specifically 2,000 to 12,000 g / mol.

[0126] An alkoxysilane functionalized component or an acylsilane functionalized component containing one silyl group can be used in combination with an alkoxysilane functionalized component or an acylsilane functionalized component containing two or more silyl groups to reduce Tg and increase the overall flexibility of the alkoxysilane functionalized component or the acylsilane functionalized component.

[0127] Based on the total amount of part A and part B, the alkoxysilane functionalized component or the acylsilane functionalized component may be used in an amount of about 35 to about 70% by weight.

[0128] The oxidant can be a peroxide, such as perbenzoate (e.g., tert-butyl perbenzoate), benzoyl peroxide (“BPO”), or cumene hydroperoxide.

[0129] Based on the total amount of part A and part B, the oxidant may be used in an amount of about 0.5 to about 7.5% by weight.

[0130] Based on the total amount of portions of composition A and composition B, the reducing agent may be present in an amount of about 0.25 to about 5% by weight. Typically, a nitrogen-containing component is used as the reducing agent, such as a dihydropyridine derivative, such as dihydrophenylpyridine (also known as phenyl dihydropyridine or “PDHP”), dimethyl-p-toluene (“DMpT”), dihydroquinoline, dihydroisoquinoline, or other readily oxidizable partially aromatic nitrogen-containing compounds. A preferred dihydropyridine additive is prepared by the condensation of butyraldehyde and aniline, forming 3,5-diethyl-1,2-dihydro-1-phenyl-2-propylpyridine (a PDHP product). Commercially available forms of PDHP include REILLCAT P50 and REILLY PDHP from Vertellus Specialties, Inc., Indianapolis, IN; VANAX 808 from RTVanderbilt; and VULKACIT 576 from Lanxess Corp.

[0131] Based on the total amount of part A and part B, the reducing agent can be used in an amount of about 0.25 to about 5% by weight.

[0132] As mentioned earlier, when the reducing agent is a nitrogen-containing component, transition metals are also present. A non-exhaustive list of representative examples of transition metal compounds includes copper compounds, vanadium compounds, cobalt compounds, and iron compounds.

[0133] For example, copper compounds in which copper has a 1+ or 2+ valence state are desirable. A non-exhaustive list of examples of such copper(I) and copper(II) compounds includes copper(II) 3,5-diisopropylsalicylate hydrate, copper bis(2,2,6,6-tetramethyl-3,5-heptadecanoate), copper(II) basic phosphate, copper(II) hydroxide phosphate, copper(II) chloride, copper(II) acetate monohydrate, copper(II) hexafluorophosphate tetra(acetonitrile) hydrate, copper(II) formate hydrate, copper(II) tetraacetonitrile trifluoromethanesulfonate tetra(I), copper(II) tetrafluoroborate, copper(II) perchlorate, copper(II) tetrafluoroborate tetra(acetonitrile) hydrate, copper(II) hydroxide, copper(II) hexafluoroacetylacetonate (II) hydrate, and copper(II) carbonate. These copper (I) and copper (II) compounds should be used in amounts such that, when dissolved or suspended in a carrier vehicle (such as (meth)acrylate), the concentration in the solution or suspension is from about 100 ppm to about 5000 ppm, such as from about 500 ppm to about 2500 ppm, such as about 1000 ppm.

[0134] For vanadium compounds, those in which vanadium has both 2+ and 3+ valence states are desirable. Examples of such vanadium(III) compounds include vanadyl naphthanate and vanadium acetylacetonate. These vanadium(III) compounds should be used in amounts from 50 ppm to about 5000 ppm, such as from about 500 ppm to about 2500 ppm, such as about 1000 ppm.

[0135] For cobalt compounds, those in which cobalt has a 2+ valence state are preferred. Examples of such cobalt(II) compounds include cobalt naphthenate, cobalt tetrafluoroborate, and cobalt acetylacetonate. These cobalt(II) compounds should be used in amounts from about 100 ppm to about 1000 ppm.

[0136] For iron compounds, those in which iron has a 3+ valence state are preferred. Examples of such iron (III) compounds include ferric acetate, ferric acetylacetonate, ferric tetrafluoroborate, ferric perchlorate, and ferric chloride. These iron compounds should be used in amounts from about 100 ppm to about 1000 ppm.

[0137] Transition metals may be used in amounts from about 0.005% by weight (or 50 ppm) to about 0.5% by weight (or 5000 ppm).

[0138] After mixing the portion A composition and the portion B composition of the first aspect together, the composition is cured at room temperature for about 24 hours to 90% of its final strength. Upon curing, the composition exhibits at least one of the following: an lap shear strength on an aluminum substrate greater than about 2.5 MPa, a linear shrinkage rate less than about 8%, a Shore A hardness greater than about 40, and an elongation percentage greater than 200%.

[0139] Additives may be included in either or both of the portion of composition A or the portion of composition B to affect a variety of performance properties.

[0140] For example, fillers can be used, including, for example, aluminum nitride, boron nitride, silicon carbide, diamond, graphite, beryllium oxide, magnesium oxide, silica (such as fumed silica or fused silica), alumina, and perfluorocarbon polymers (…). Right now The fillers include TEFLON, thermoplastic polymers, thermoplastic elastomers, mica, glass powder, etc. Preferably, the particle size of these fillers will be about 20 micrometers or smaller.

[0141] For silica, silica can have an average particle size of nanoparticle size; that is, an average particle size on the order of 10. -9 The average particle size is [number] meters. Silica nanoparticles can be pre-dispersed in epoxy resins and can be selected from those available under the trade name NANOCRYL from Nanoresins, Germany. NANOCRYL is a trade name for a series of silica nanoparticle-reinforced (meth)acrylate products. The silica phase consists of surface-modified synthetic SiO2 nanospheres with a diameter of less than 50 nm and an extremely narrow particle size distribution. The SiO2 nanospheres are agglomerated dispersions in a (meth)acrylate matrix, resulting in low viscosity for resins containing up to 50% by weight of silica.

[0142] It may also contain (especially in part A of the composition) rubber particles (particularly those with a relatively small average particle size). example like Rubber particles (smaller than approximately 500 nm or smaller than approximately 200 nm). The rubber particles may or may not have a shell common to known core-shell structures.

[0143] In the case of rubber particles with a core-shell structure, such particles typically have a core surrounded by a shell, the core having elastomeric or rubber-like properties. Right now The glass transition temperature is less than approximately 0°C. For example, The shell is made of a polymer material with a temperature below approximately -30°C, and is composed of a non-elastomeric polymer material ( Right now The glass transition temperature is higher than the ambient temperature. example like The core is composed of thermoplastic or thermosetting / crosslinked polymers with a temperature greater than about 50°C. For example, the core may be composed of diene homopolymers or copolymers (e.g., homopolymers of butadiene or isoprene, copolymers of butadiene or isoprene with one or more olefinically unsaturated monomers (e.g., vinyl aromatic monomers, (meth)acrylonitrile, (meth)acrylates, etc.), while the shell may be composed of one or more monomers with a suitably high glass transition temperature (e.g., (meth)acrylates). For example methyl methacrylate), vinyl aromatic monomers ( For example, Styrene), vinyl cyanide For example Acrylonitrile), unsaturated acids and acid anhydrides ( For example, It is composed of polymers or copolymers of acrylic acid, (meth)acrylamide, etc. Other rubbery polymers may also be suitably used for the core, including polybutyl acrylate or polysiloxane elastomers (…). For example, Polydimethylsiloxane, especially cross-linked polydimethylsiloxane.

[0144] Typically, the core will account for about 50 to 95% of the weight of the rubber pellet, while the shell will account for about 5 to 50% of the weight of the rubber pellet.

[0145] Preferably, the size of the rubber particles is relatively small. For example, the average particle size can be from about 0.03 to about 2 micrometers or from about 0.05 to about 1 micrometer. The average diameter of the rubber particles can be less than about 500 nm, such as less than about 200 nm. For example, the average diameter of core-shell rubber particles can be in the range of about 25 to about 200 nm.

[0146] When used, due to their large, uniform dispersion, these core-shell rubbers allow toughening to occur in the composition in a temperature-neutral manner toward curing, and this usually occurs in a predictable way, as is commonly observed in core-shell rubbers, as they are offered for commercial sale.

[0147] In the case of rubber particles that do not have such a shell, the rubber particles can be based on a core with such a structure.

[0148] Ideally, the size of the rubber particles is relatively small. For example, the average particle size can be from about 0.03 to about 2 μm or from about 0.05 to about 1 μm. In some embodiments of the invention, the average diameter of the rubber particles is less than about 500 nm. In other embodiments, the average particle size is less than about 200 nm. For example, the average diameter of the rubber particles can be in the range of about 25 to about 200 nm or from about 50 to about 150 nm.

[0149] As mentioned above, rubber granules can be used in dry form or dispersed in a matrix.

[0150] Typically, the composition may contain about 5 to about 35% by weight of rubber particles.

[0151] Combinations of different rubber particles can be advantageously used in this invention. The rubber particles can differ in, for example, particle size; the glass transition temperature of their respective materials; whether the materials are functionalized, to what extent and by what means; and whether their surfaces are treated, to what extent and by how.

[0152] Suitable rubber granules for use in this invention are commercially available. For example, rubber granules supplied by Eliokem, Inc., such as NEP R0401 and NEP R401S (both based on acrylonitrile / butadiene copolymer); NEP R0501 (based on carboxylated acrylonitrile / butadiene copolymer; CAS No. 9010-81-5); NEP R0601A (based on hydroxyl-terminated polydimethylsiloxane; CAS No. 70131-67-8); and NEP R0701 and NEP 0701S (based on butadiene / styrene / 2-vinylpyridine copolymer; CAS No. 25053-48-9), can be used. There are also those obtained under the trade name PARALOID (such as PARALOID2314, PARALOID 2300 and PARALOID 2600) from Dow Chemical Co., Philadelphia, PA, and those obtained under the trade name STAPHYLOID (such as STAPHYLOID AC-3832) from Ganz Chemical Co., Ltd., Osaka, Japan.

[0153] It has been treated with reactive gases or other reagents to generate polar groups, for example, on the particle surface. example like, Rubber particles whose outer surface is modified with hydroxyl or carboxylic acid groups are also suitable for use herein. Exemplary reactive gases include, for example, ozone, Cl2, F2, O2, SO3, and oxidizing gases. Methods for surface modification of rubber particles using such reagents are known in the art and described, for example, in U.S. Patent Nos. 5,382,635; 5,506,283; 5,693,714; and 5,969,053 (each of which is hereby expressly incorporated herein by reference in its entirety). Suitable surface-modified rubber particles are also available from commercial sources, such as rubber sold by Exousia Corporation under the trade name VISTAMER.

[0154] When rubber granules are initially provided in dry form, it is advantageous to ensure that such granules are well dispersed in the adhesive composition before curing. That is, the agglomerates of rubber granules are preferably broken up to provide discrete, individual rubber granules, which can be achieved by close and thorough mixing of the dry rubber granules with the other components of the adhesive composition.

[0155] In practice, each of the components A and B is contained in a separate, sealed container within the device prior to use, wherein, upon use, the two components are extruded from the container, mixed, and applied to a substrate surface. The container may be a double-chambered cylinder, in which the individual components travel through the chambers by a plunger, through an orifice (which may be a shared or adjacent orifice), and then through a mixing and dispensing nozzle. Alternatively, the container may be a coaxial or side-by-side bag, which may be cut or torn, and its contents mixed and applied to the substrate surface.

[0156] The invention will be more readily understood by referring to the following embodiments.

[0157] Example

[0158] Referring to Table 1, adhesive systems were prepared to evaluate Methyl methacrylate-based Part A compositions (containing varying amounts of either or both of isoborneol acrylate or isoborneol methacrylate) and silane-modified polymer-based Part B compositions (containing an oxidant in all but one example). Part A compositions also contained varying amounts of SIS block copolymers, reactive acid components, reducing agents, and inhibitor / accelerator packages. Part A compositions also contained a stabilizer package in an amount of about 1% by weight. The adhesive systems in Table 1 were varied in mixing ratios (volume percentages) of 0:1, 1:2, 1:1, 2:1, and 9:1.

[0159] Table 1

[0160] Part A

[0161]

[0162] ！ KRATON D1114 is commercially available from Kraton Corporation and is reported by the manufacturer as a transparent linear block copolymer of styrene and isoprene with a polystyrene content of 19%. D1114 has a tensile strength of 4600 psi, an elongation at break of 1300%, a specific gravity of 0.92, and a modulus of 300% at 270 psi.

[0163] @HARCRYL 1228 is commercially available from Harcros Chemicals, Kansas City, KS, and is reported by the manufacturer as a unique functional acrylic monomer composed of mono- and di-phosphates of 2-hydroxyethyl methacrylate. The monoalkyl phosphate to dialkyl phosphate ratio allows HARCRYL 1228 to be readily incorporated into a wide variety of polymer systems. The polarity of HARCRYL 1228 also provides applications in hydrophilic formulations. The phosphate functional groups promote adhesion to a variety of surfaces, thereby reducing the need for pretreatment.

[0164] #DMpT is dimethyl-p-toluidine.

[0165] Part B

[0166]

[0167] TEROSTAT MS 939, commercially available from Henkel AG & Co. KGaA, Dusseldorf, Germany, is a gun-grade, one-component sealant based on silane-modified polymers that cures into an elastic product through reaction with moisture. Skin formation and curing time depend on humidity and temperature, and curing time also depends on the depth of the joint. These times can be reduced by increasing temperature and humidity; low temperatures and low humidity slow the process. TEROSTAT MS 939 is particularly resistant to sagging, resulting in high positional tack after the parts to be bonded are matched. TEROSTAT MS 939 is free of solvents, isocyanates, silicones, and PVC. It exhibits good adhesion to many substrates and is compatible with suitable paint systems. The sealant also exhibits good UV resistance, making it suitable for both indoor and outdoor applications. TEROSTAT MS 939 exhibits the strength required for elastic bonding. This property of the product is also maintained at temperatures in a repair oven (maximum 100°C). TEROSTAT MS 939 showed no shrinkage, and therefore no dents or tensile stresses were observed under these conditions. TEROSTAT MS 939 allows for accelerated curing as a two-component material.

[0168] %H8000, part B, is available from Henkel Corporation.

[0169] The physical properties (including tensile strength and elongation percentage) of the adhesive system in Table 1 were evaluated and are shown in Table 2 below. Sample No. 0 is TEROSTAT MS 939 in a single-part form without part A of the composition.

[0170] Table 2

[0171]

[0172] Compared to the control samples (sample 0 due to the 100% SMP formulation, and samples 1, 3 and 5 due to the 100% acrylic formulation), samples 2, 4, 6, 7 and 8 showed impressive elongation percentage values.

[0173] In Table 3, similar to Table 1 above, alkyl (meth)acrylates are present in composition A of the adhesive system. However, as a replacement for isobornyl (meth)acrylate (“IBOA”) used alone in composition A of Table 1, ethylhexyl acrylate (“EHA”) is used in both samples with IBOA, and lauryl methacrylate (“LMA”) is used in one sample. The adhesive systems in Table 3 are mixed in a 1:1 ratio (volume percentage).

[0174] Table 3, Part A

[0175]

[0176] ! KRATON D1114

[0177] @CLEARSTRENGTH XT100 is commercially available from Arkema Inc., Cary, NC and is described as a methyl methacrylate-butadiene-styrene core-shell toughening agent that is compatible with a variety of monomers and readily dispersed in most liquid resin systems, exhibiting limited effect on their viscosity while providing toughening effects over a wide operating temperature range.

[0178] Part B

[0179]

[0180] %H8000, part B.

[0181] The tensile properties of the adhesive systems in Table 3 are evaluated and are shown in Table 4 below.

[0182] Table 4

[0183]

[0184] In Table 5, the BPO-amine redox system from Table 1 above is replaced with the TBPB-PDHP / Cu redox system. Furthermore, one of the A compositions here contains a filler, and one of the B compositions contains a (meth)acrylate functionalized component, a SIS copolymer, and a (meth)acrylate alkyl ester component (each of which is typically present only in the A composition). The binder systems in Table 5 are varied in mixing ratios (volume percentage) of 1:2, 1:1, and 2:1.

[0185] Table 5, Part A

[0186]

[0187] %KRATON D1113 P is commercially available from Kraton Corporation and is reported by the manufacturer as a transparent linear block copolymer of styrene and isoprene with a polystyrene content of 16%. D1113P has a tensile strength of 600 psi, an elongation at break of 1500%, a specific gravity of 0.92, and a modulus of 300% at 50 psi.

[0188] Part B

[0189]

[0190] ^KRATON D1113 PT, available from Kraton Corporation.

[0191] Evaluate the physical properties of the adhesive systems in Table 5, which are shown in Table 6 below.

[0192] Table 6

[0193]

[0194] The physical properties of sample 0 are shown again for comparison purposes. Sample 0 is a single-component TEROSTAT MS 939 without the A component. Here, without the acrylic component, sample 0 shows an elongation percentage of 250. Sample 15 (100% acrylic formulation) shows an elongation percentage of 235, while sample 13 shows a much larger elongation percentage (371). This value is not only higher than that of the 100% acrylic formulation (sample 15), but also higher than that of the 100% SMP formulation (sample 0) which shows an elongation percentage of 250. Even when filler is added (sample 16), the elongation percentage remains quite large (i.e., 313).

[0195] In Table 7, IBOA from Table 5 was replaced with EHA and EHMA, and the TBPB-PDHP / Cu redox system was used with the SIS copolymer. The adhesive systems in Table 7 are mixed at a 1:1 ratio (volume percentage).

[0196] Table 7

[0197] Part A

[0198]

[0199] &KRATON D1114

[0200] Part B

[0201]

[0202] ! KRATON D1114

[0203] Table 8

[0204]

[0205] In Table 7, the adhesive systems in some B compositions that do not contain the SMP component (samples 17 and 19) show elongation percentages of 243 and 206, respectively, while the adhesive systems in some B compositions that contain the SMP component (samples 18 and 20) show elongation percentages of 346 and 298, respectively. These latter adhesive systems show higher elongation percentages than adhesive systems based solely on the SMP component or (meth)acrylic components.

[0206] In Table 9, the rubber toughening agent in liquid rubber form (VTB-LC) is included in part A composition, and two different block copolymers are evaluated. In two samples, the block copolymers are also included in part B composition. These adhesive systems use the TBPB-PDHP / Cu redox system. The adhesive systems in Table 9 are varied with mixing ratios of 1:2, 1:1, and 2:1 and individual MMA (volume percentage).

[0207] Table 9

[0208] Part A

[0209]

[0210] *KRATON D1113 P

[0211] (KRATON D1114) VTB-LC, commercially available from CVC Thermoset Specialties, is reported by the manufacturer as a low molecular weight methacrylate functionalized liquid synthetic rubber. It is a 100% solid reactive polymer primarily used as an additive in acrylic adhesives, sealants, coatings, and composites. VTB-LC has a viscosity of ~80,000 cps, functionality of 1.9, molecular weight of 4450, glass transition temperature of -80°C, and specific gravity of 0.929.

[0212] Part B

[0213]

[0214] *KRATON D1113 P

[0215] (KRATON D1114) VTB-LC

[0216] As shown in Table 10 below, the adhesive systems in Table 9 that do not contain the SMP component in part B exhibit an elongation percentage of less than about 200. Even sample number 0 (shown in Tables 1 and 2, containing only the SMP component in part B and no (meth)acrylic acid in part A) shows a better elongation percentage (about 250). However, the adhesive systems in Table 9 that contain acrylic acid components in part A and SMP components in part B exhibit much larger elongation percentages, reportedly as large as almost about 500.

[0217] Table 10

[0218]

[0219] Table 11 presents adhesive systems similar to those in Table 9, but without IBOA, and with the SIS copolymer replaced by the SBS copolymer. The adhesive systems in Table 11 are mixed in a 1:1 ratio (volume percentage).

[0220] Table 11

[0221] Part A

[0222]

[0223] ! KRATOND1155

[0224] Part B

[0225]

[0226] KRATON D1155

[0227] Table 12 below shows that the adhesive system in Table 11 that does not contain the SMP component (sample number 29) exhibits a very low elongation percentage (21), but the adhesive system in Table 11 that contains the SMP component (sample number 30) has an elongation percentage that increases to 154%.

[0228] Table 12

[0229]

[0230] In Table 13, the adhesive system in part A contains no reactive acid component. Otherwise, the adhesive system is equivalent to the adhesive systems shown in Table 1, part A, and samples 5 and 7 above.

[0231] Table 13

[0232] Part A

[0233]

[0234] ! KRATON D 1114

[0235] Part B

[0236]

[0237] @H8000, some B

[0238] Even without reactive acid components, sample number 32 still exhibited a high percentage of elongation (428).

[0239] Table 14

[0240]

[0241] Referring to Table 15, adhesive systems were prepared to evaluate fraction A compositions containing isoborneol acrylate with an oxidizing agent and fraction B compositions based on silane-modified polymers with a reducing agent. Fraction A compositions also contained SIS block copolymers, and three of the four samples also contained (meth)acrylate-functionalized urethanes (such as resin A).

[0242] Table 15, Part A

[0243]

[0244] KRATON D1114 is commercially available from Kraton Corporation and is reported by the manufacturer as a transparent linear block copolymer of styrene and isoprene with a polystyrene content of 19%. D1114 has a tensile strength of 4600 psi, an elongation at break of 1300%, a specific gravity of 0.92, and a modulus of 300% at 270 psi.

[0245] #LUPEROX APF55 is available from Arkema Inc.

[0246] Part B

[0247]

[0248] TEROSTAT MS 939, commercially available from Henkel AG & Co. KGaA, Dusseldorf, Germany, is a gun-grade, one-component sealant based on a silane-modified polymer that cures into an elastic product through reaction with moisture. Skin formation and curing time depend on humidity and temperature, and curing time also depends on the depth of the joint. These times can be reduced by increasing temperature and humidity; low temperatures and low humidity slow the process. TEROSTAT MS 939 is particularly resistant to sagging, resulting in high positional tack after the parts to be bonded are matched. TEROSTAT MS 939 is free of solvents, isocyanates, silicones, and PVC. It exhibits good adhesion to many substrates and is compatible with suitable paint systems. The sealant also exhibits good UV resistance, making it suitable for both indoor and outdoor applications. TEROSTAT MS 939 exhibits the strength required for elastic bonding. This property of the product is also maintained at temperatures in a repair oven (maximum 100°C). TEROSTAT MS 939 does not exhibit shrinkage, and therefore no dents or tensile stresses were observed under these conditions. TEROSTAT MS 939 allows for accelerated curing as a two-component material.

[0249] %DMpT is dimethyl-p-toluidine.

[0250] The physical properties of the adhesive system in Evaluation Table 15 (including skin overtime, adhesive and tensile properties, and percentage elongation) are shown in Table 16 below.

[0251] Table 16

[0252]

[0253] Compared with the control sample (sample 33, a comparable sample without (meth)acrylate-functionalized carbamate), samples 34-36 showed excellent fixation time and surface drying time values.

[0254] Compared to the control sample (sample 33, a comparable sample without (meth)acrylate-functionalized urethane), samples 34-36 also showed excellent adhesion, tensile strength, and percentage elongation values.

[0255] As an additional control, sample number 37 is TEROSTATMS 939 in a single-part form without part A of the composition. Sample number 37 shows a tensile strength at break of 435 2" / min (psi) and an elongation at break of 250 2" / min (%).

Claims

1. A two-part adhesive composition, said two-part adhesive composition comprising: (a) Part A composition, said part A composition comprising the following components: (i) (meth)acrylate functionalized components; (ii) A block copolymer component, wherein the block copolymer component is selected from (meth)acrylate-terminated polybutadiene, styrene-isoprene-styrene block copolymers, and combinations thereof that are in liquid form at room temperature; (iii) Optional reactive acid components; and (iv) Optional additives, said additives being selected from fillers, plasticizers, adhesion promoters, catalysts, and combinations thereof; as well as (v) at least one of a reducing agent and a transition metal, or an oxidizing agent; and (b) Part B composition, said part B composition comprising: (i) An alkoxysilane-functionalized component or an acyloxysilane-functionalized component, wherein the alkoxysilane-functionalized component or the acyloxysilane-functionalized component is a silane-modified polymer having at least one hydrolyzable silyl group, the hydrolyzable silyl group being bonded to the polymer via an ether (-O-) linking group or a carbonyl group, wherein the carbonyl group is bonded to a heteroatom selected from oxygen, nitrogen, and sulfur, provided that at least one heteroatom is nitrogen. The B-component composition contains at least one of a reducing agent and a transition metal, or an oxidizing agent, provided that the A-component composition and the B-component composition do not each contain the oxidizing agent, the reducing agent, and the transition metal; The amount of the alkoxysilane functionalized component or acylsilane functionalized component used is 51.4 to 70% by weight, based on the total amount of a portion of composition A and a portion of composition B.

2. The composition of claim 1, wherein the (meth)acrylate functionalized component (i) of the composition of part A comprises a monofunctional (meth)acrylate component.

3. The composition of claim 1, wherein the (meth)acrylate functionalized component (i) of the composition of part A comprises an alkyl (meth)acrylate and / or a monofunctional (meth)acrylate component, and one or more of isobornyl (meth)acrylate, lauryl (meth)acrylate and / or ethylhexyl (meth)acrylate.

4. The composition of claim 1, wherein the (meth)acrylate functionalized component (i) of the composition of part A comprises 10 to 50% by weight of a monofunctional (meth)acrylate component.

5. The composition of claim 1, wherein the styrene-isoprene-styrene block copolymer has a weight-average molecular weight of 100,000 to 500,000 Mw.

6. The composition of claim 1, further comprising a reactive acid component.

7. The composition of claim 6, wherein the reactive acid component comprises one or more of (meth)acrylic acid and / or phosphate esters of hydroxyethyl methacrylate.

8. The composition of claim 6, wherein the reactive acid component comprises a phosphate ester of hydroxyethyl methacrylate.

9. The composition of claim 1, wherein the oxidant is a peroxide.

10. The composition of claim 1, wherein the oxidant is a perbenzoate.

11. The composition of claim 1, wherein the oxidant is tert-butyl perbenzoate, benzoyl peroxide, or cumene hydroperoxide.

12. The composition of claim 1, wherein the oxidant is present in an amount of 0.01% to 10% by weight.

13. The composition of claim 1, wherein the reducing agent is a nitrogen-containing component and / or a transition metal-containing compound.

14. The composition of claim 13, wherein the nitrogen-containing component is present in an amount of 0.01% to 10% by weight.

15. The composition of claim 13, wherein the transition metal in the compound containing the transition metal is selected from copper, vanadium, cobalt and iron.

16. The composition of claim 13, wherein the transition metal-containing compound is present in an amount of 0.005% by weight to 0.5% by weight.

17. The composition of claim 1, wherein the composition of part A further comprises a reactive acid component.

18. The composition of claim 1, wherein when mixed together, the two-part adhesive composition cures to 90% of its final strength at room temperature within 24 hours.

19. The composition of claim 1, wherein, upon curing, the two-part adhesive composition exhibits at least one of the following: a tensile strength greater than 2.5 MPa on an aluminum substrate, a linear shrinkage rate of less than 8%, a Shore A hardness greater than 40, and an elongation greater than 200%.

20. The composition of claim 1, further comprising an alkyl (meth)acrylate component.

21. The composition of claim 20, wherein the alkyl methacrylate component is selected from polyethylene glycol di(meth)acrylate, tetrahydrofuran(meth)acrylate and tetrahydrofuran di(meth)acrylate, hydroxypropyl methacrylate, hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, benzyl methacrylate, tetraethylene glycol dimethacrylate, dipropylene glycol dimethacrylate, di-(1,5-)methacrylate, di ... -Pentene diol) dimethacrylate, tetraethylene diethylene glycol diacrylate, diglycerol tetramethacrylate, tetramethyl dimethacrylate, dimethacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, and bisphenol A mono(meth)acrylate and bisphenol A di(meth)acrylate, bisphenol F mono(meth)acrylate and bisphenol F di(meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, and (meth)acrylated polyacrylate.

22. The composition of claim 1, wherein portion A of the composition is contained in the first chamber of the dual-chamber syringe, and portion B of the composition is contained in the second chamber of the dual-chamber syringe.

23. The composition of claim 1, wherein the B portion of the composition further comprises at least one of a toughening agent, a plasticizer, or a filler.

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