Water bonding method

Abstract

A method for bonding underwater substrates comprising applying a cyanoacrylate composition to at least one substrate in water and curing the composition in water.

Description

[Technical Field]

[0001] The present invention provides a method for underwater bonding with a curable cyanoacrylate composition. [Background technology]

[0002] Curable compositions such as cyanoacrylate adhesives are widely known for their excellent ability to rapidly bond a variety of substrates, usually within minutes, and sometimes even within seconds depending on the particular substrate.

[0003] Cyanoacrylate adhesive compositions are well known and widely used as fast-curing instant adhesives in a variety of applications. See H.V. Coover, D.W. Dreyfuss, and J.T. O'Connor, "Cyanoacrylate Adhesives," Adhesives Handbook, vol. 27, pp. 463-77, edited by I. Skiest, Van Nostrand & Reinhold, New York, 3rd ed. (1990). See also G.H. Millett, "Cyanoacrylate Adhesives," Structural Adhesives: Chemistry and Technology, edited by S. R. Hartshorne, Plenum Press, New York, pp. 249-307 (1986).

[0004] Cyanoacrylate adhesive compositions are suitable for air curing: they reach handleable strength in a few seconds when cured in air, and greater than 60% strength when cured in air within one minute.

[0005] The polymerization of cyanoacrylates is initiated by nucleophiles present on most surfaces under normal atmospheric conditions. Initiation by surface chemistry means that sufficient initiating species are available when two surfaces are in intimate contact with a small layer of cyanoacrylate between them. Under these conditions, strong adhesion can be achieved in a short time. Thus, cyanoacrylates often function essentially as instant adhesives.

[0006] Cyanoacrylate adhesive compositions are difficult to dispense underwater and therefore have not traditionally been used for underwater applications. Underwater is understood to mean that the substrates to be bonded are completely submerged in water. The water is in contact with the substrate. As used herein, underwater does not refer to a situation in which the substrate is underwater but not in contact with the water. For example, underwater does not refer to a substrate contained in a waterproof container, where the container is in contact with water but the waterproof container keeps the substrate dry and prevents the substrate from contacting the water. In particular, the present invention relates to a method of using a cyanoacrylate adhesive dispensed from a container underwater. In such cases, the cyanoacrylate adhesive is dispensed through the water onto the substrate surface, which is also in contact with the water.

[0007] Dispensing a cyanoacrylate adhesive composition in water can cause the composition to react with the water and prematurely cure before it is applied to the substrate to be bonded. Indeed, cyanoacrylate compositions are well known to be sensitive to water, and in some cases, even trace amounts of water can cause premature curing, for example, while they are being stored for later use.

[0008] The performance, especially durability, of cyanoacrylate adhesives is often questionable when exposed to water. Bonds formed using cured cyanoacrylate compositions can be susceptible to water. For example, cured cyanoacrylate compositions deteriorate over time when exposed to water, so the bonds formed can eventually fail. In general, exposure to water reduces adhesive strength over time.

[0009] A cyanoacrylate adhesive composition dispensed in water may be applied to a first substrate and then partially cured before being bonded to a second substrate. In this case, it is possible to form a bond between the substrates, but the bond will be weak because the composition was partially cured before the substrates were bonded.

[0010] To overcome these problems, the cyanoacrylate adhesive composition is typically applied to a substrate in air, and the bonded substrates may then be placed in water.

[0011] Underwater bonding using a cyanoacrylate adhesive composition would be advantageous in applications where the properties of the cyanoacrylate adhesive composition are beneficial. In situations where it is difficult to remove the substrate from the water, it would be beneficial to dispense and cure the cyanoacrylate adhesive composition underwater. For example, when repairing or maintaining a boat or installing new parts, such as sensors, on a boat, it would be beneficial to use a cyanoacrylate adhesive composition to bond underwater boat parts, since this would eliminate the need to remove the boat from the water, which would be difficult and expensive and would require the vessel to be returned to shore. Similarly, it would be useful to be able to perform underwater maintenance and repairs or to attach parts to structures that are fully or partially underwater, such as oil rigs, bridges, and pipelines.

[0012] Coral reefs are formed by colonies of coral polyps. Their skeletons are made of calcium carbonate, and the coral polyps are held together by this calcium carbonate skeleton. The majority of coral reefs are formed by stony coral polyps (also called scleractinia). Stony corals secrete a hard calcium carbonate exoskeleton that protects and supports the reef. Coral reefs can be damaged, for example, by excess nutrients or ocean acidification. Coral transplantation is considered a viable method for helping reefs recover from damage. Healthy coral polyps are transplanted from healthy reefs to damaged reefs. These healthy polyps may aid in the restoration of the reef. Transplanted coral polyps are fixed in their new location using cement or epoxy. If the transplanted coral polyp becomes dislodged from its original location, it will die and the transplant will not be successful. These methods can require a long time for the epoxy to be dispensed, applied, and cured. This means that users, such as divers, must remain underwater for extended periods of time, which can be costly and dangerous.

[0013] Dizon et al. compared the use of a cyanoacrylate adhesive gel composition, an epoxy putty, and a marine epoxy to determine their suitability for adhering coral polyps. Dizon et al. applied the cyanoacrylate adhesive composition on water, then submerged the coral polyps. Dizon et al. found that the cyanoacrylate adhesive composition was the easiest to work with, but performed poorly in the important areas of adhesive effectiveness and self-adhesion of the graft.

[0014] It would be beneficial to provide an adhesive composition that has the advantages of cyanoacrylate compositions and is effective for adhering coral polyps during transplantation.

[0015] It would be beneficial to provide an alternative adhesive that (1) can be dispensed while submerged in water, (2) does not cure long enough to allow application to the substrate to be bonded, (3) subsequently cures in a desirably short cure time, (4) forms a high strength bond, and (5) retains bond strength, all of which must be accomplished underwater. Summary of the Invention [Means for solving the problem]

[0016] In one aspect, the present invention provides a method for producing a medicament comprising: applying a cyanoacrylate composition to at least one substrate in water; The cyanoacrylate composition comprises: a first part comprising a cyanoacrylate component and a cationic catalyst; a cationically curable component such as an epoxy component, an episulfide component, an oxetane component, and combinations thereof; and a second part comprising an initiator component; curing the composition in water; The present invention provides a method for bonding underwater substrates, comprising:

[0017] By "underwater" we mean that the substrate is submerged in water and the composition is applied while the water is in contact with the substrate. The substrate is not directly exposed to water, e.g., it is not enclosed in a waterproof container. The advantage of this method is that it allows underwater bonding in applications that were previously precluded by the inability to remove and dry the assembly before bonding.

[0018] Advantageously, compositions applied in this manner can be dispensed while submerged in water, remain uncured long enough to be applied to the substrate to be bonded, and then cure in a short cure time. Advantageously, cured compositions cured in water form high-strength bonds and maintain their bond strength over time. The compositions have an open time long enough to allow for dispensing, application, and bonding of substrates before the composition hardens, yet desirably have a shorter cure time than compositions used in traditional methods to minimize the time the user spends in water.

[0019] The recognized drawbacks of cyanoacrylate compositions for bonding underwater substrates may be overcome by the cyanoacrylate hybrid compositions disclosed herein. All of the desirable properties of the present invention refer to the properties of the composition in an underwater environment. The compositions of the present invention remain in place when dispensed. The compositions of the present method can be dispensed underwater, and for example, do not undergo premature curing upon initial contact with water, which would prevent the composition from being dispensed onto a substrate. While a film may form where there is initial contact with water, curing does not occur throughout the volume of the composition, and dispensing is not prevented. The compositions of the present method may have an appropriate viscosity to allow dispensing. The compositions may also have appropriate buoyancy. For example, the compositions of the present method are suitable for not being displaced by forces caused by normal water currents.

[0020] The composition is dispensed underwater and can be used to bond underwater substrates. While not wishing to be bound by theory, it is believed that the combination of the hybrid's epoxy portion for controlled cure speed and the material's inherent high viscosity results in this unexpected open time in aqueous environments. The cone and plate viscosity of Part 1 of the composition can be 4,000-7,000 mPa·s. The viscosity of Part 2 can be 25,000-40,000 mPa·s. Both viscosities are measured according to ASTM D7867.

[0021] Additionally, the cationically curable component may initiate the cure of the cyanoacrylate.

[0022] The cyanoacrylate component of the cyanoacrylate composition applied in the present method may be selected from materials within the structure H2C=C(CN)-COOR, where R is C 1~15 Alkyl group, C 2~15 Alkoxyalkyl group, C 3~15 Cycloalkyl groups, C 2~15 Alkenyl group, C 6~15 Aralkyl group, C 5~15 Aryl group, C 3~15 Allyl group, and C 1~15 The haloalkyl group is selected from, for example, a cyanoacrylate component includes ethyl-2-cyanoacrylate ("ECA").

[0023] The cyanoacrylate component should be included in the Part A composition in an amount ranging from about 50% to about 99.98% by weight of the total composition, with, for example, about 65% to about 85% by weight being desirable, and about 75% to about 97% by weight being particularly desirable.

[0024] The cationic catalyst included in the Part A composition of the two-component adhesive system must be a hard cationic non-nucleophilic anionic catalyst. Examples of such catalysts include lithium salts, Group II metal salts, and non-nucleophilic acids. These non-nucleophilic acids have a pH of less than 1.0 when measured as a 10% by weight solution in water, and the anionic portion of such acids readily participates in substitution reactions with organic halides. Examples of Group II metal salts include calcium and magnesium. Examples of non-nucleophilic acids include perchloric acid, fluoroboric acid, fluoroarsenic acid, fluoroantimonic acid, and fluorophosphoric acid. Thus, examples of hard cationic non-nucleophilic anionic salts include lithium tetrafluoroborate, calcium ditetrafluoroborate, magnesium ditetrafluoroborate, lithium hexafluorophosphate, calcium dihexafluorophosphate, magnesium dihexafluorophosphate, lithium hexafluoroantimonate, and lithium hexafluoroarsenate.

[0025] Cationic catalysts may also include lanthanide triflate salts, aryliodonium salts, arylsulfonium salts, lanthanum triflate, ytterbium triflate, trimethoxyboroxine, trimethoxyboroxine-aluminum acetylacetonate, amine-boron trihalide complexes, quaternary ammonium salts, quaternary phosphonium salts, triarylsulfonium salts, diaryliodonium salts, and diazonium salts.

[0026] Another cationic catalyst suitable for use in the Part A composition of the adhesive system is a trialkoxyboroxine curing agent, such as those described in U.S. Patent Nos. 4,336,367 and 6,617,400, the disclosures of each of which are incorporated herein by reference. Of course, two or more of these cationic catalysts may be used in combination.

[0027] Also suitable for use as partial or complete cationic catalysts are boron trifluoride, boron trifluoride etherate, sulfur trioxide (and its hydrolysis products), and methanesulfonic acid, which are often used to stabilize cyanoacrylate monomers against anionic polymerization (see below), a known problem in shelf-life stabilization.

[0028] Typically, the amount of cationic catalyst ranges from about 0.001% to about 10.00% by weight of the composition, desirably from about 0.01% to about 5.00% by weight of the composition, for example, about 0.50-2.50% by weight of the composition.

[0029] The Part A composition of the adhesive system may include additives to impart physical properties such as improved fixation speed, improved shelf life stability, flexibility, thixotropy, increased viscosity, color, and improved toughness. Accordingly, such additives may be selected from accelerators, free radical stabilizers, anionic stabilizers, gelling agents, thickeners (such as PMMA), thixotropic agents (such as fumed silica), dyes (such as carbon black), toughening agents, plasticizers, and combinations thereof.

[0030] These additives are described in more detail below, but for now we will focus on accelerators and stabilizers.

[0031] The adhesive system, particularly the Part A composition, may use one or more accelerators to accelerate the cure of the cyanoacrylate component. Such accelerators may be selected from calixarenes and oxacalixarenes, silacrowns, crown ethers, cyclodextrins, poly(ethylene glycol) di(meth)acrylates, ethoxylated hydrated compounds, and combinations thereof.

[0032] Many calixarenes and oxacalixarenes are known and have been reported in the patent literature, see, e.g., U.S. Patent Nos. 4,556,700, 4,622,414, 4,636,539, 4,695,615, 4,718,966, and 4,855,461, the disclosures of each of which are expressly incorporated herein by reference.

[0033] For example, with respect to calixarenes, those within the following structure are useful in the present invention:

[0034] [ka]

[0035] In the formula, R 1 is alkyl, alkoxy, substituted alkyl, or substituted alkoxy; R 2 is H or alkyl and n is 4, 6, or 8.

[0036] One particularly desirable calixarene is tetrabutyltetra[2-ethoxy-2-oxoethoxy]calix-4-arene.

[0037] Many crown ethers are known, including, for example, 15-crown-5, 18-crown-6, dibenzo-18-crown-6, benzo-15-crown-5-dibenzo-24-crown-8, dibenzo-30-crown-10, tribenzo-18-crown-6, unsymmetrical dibenzo-22-crown-6, dibenzo-14-crown-4, dicyclohexyl-18-crown-6, dicyclohexyl-24-crown-8, cyclohexyl-12-crown-4, 1,2-decalyl-15-crown-5, 1,2-naphthalene-15-crown-5, 1,2-naphthalene-15-crown-6 ... Examples of suitable benzo-1,4-benzo-5-oxygen-20-crown-7 include benzo-1,4-benzo-5-hydroxybenzo-15-crown-5, 3,4,5-naphthyl-16-crown-5, 1,2-methylbenzo-18-crown-6, 1,2-methylbenzo-5, 6-methylbenzo-18-crown-6, 1,2-t-butyl-18-crown-6, 1,2-vinylbenzo-15-crown-5, 1,2-vinylbenzo-18-crown-6, 1,2-t-butyl-cyclohexyl-18-crown-6, asymmetric dibenzo-22-crown-6, and 1,2-benzo-1,4-benzo-5-oxygen-20-crown-7. See U.S. Pat. No. 4,837,260 (Sato), the disclosure of which is expressly incorporated herein by reference.

[0038] Of the silacrowns, many are also known and have been reported in the literature. For example, a typical silacrown may be represented by the following structure:

[0039] [ka]

[0040] In the formula, R 3 and R 4 is an organic group that does not itself cause polymerization of the cyanoacrylate monomer, and R 5 is H or CH3, and n is an integer from 1 to 4. 3 and R 4 Examples of groups are R groups, alkoxy groups such as methoxy groups, and aryloxy groups such as phenoxy groups. 3 and R 4The group may contain halogen or other substituents, an example being trifluoropropyl. However, R 4 and R 5 Groups that are not suitable as groups are basic groups such as amino, substituted amino, and alkylamino.

[0041] Specific examples of silacrown compounds useful in the compositions of the present invention include the following:

[0042] [ka]

[0043] [ka]

[0044] [ka]

[0045] See, for example, U.S. Patent No. 4,906,317 (Liu), the disclosure of which is expressly incorporated herein by reference.

[0046] Many cyclodextrins may be used in connection with the present invention. For example, those described and claimed in U.S. Patent No. 5,312,864 (Wens), the disclosure of which is expressly incorporated herein by reference, as hydroxyl derivatives of α, β, or γ-cyclodextrin that are at least partially soluble in cyanoacrylates are suitable choices for use herein as the promoter component.

[0047] Additionally, poly(ethylene glycol) di(meth)acrylates suitable for use herein include those within the following structure:

[0048] [ka]

[0049] In the formula, n is greater than 3, for example, in the range of 3 to 12, with n being particularly preferred at 9. More specific examples include PEG200DMA (n is approximately 4), PEG400DMA (n is approximately 9), PEG600DMA (n is approximately 14), and PEG800DMA (n is approximately 19). The number (e.g., 400) represents the average molecular weight of the glycol portion of the molecule, excluding the two methacrylate groups, and is expressed in grams / mole (i.e., 400 g / mol). A particularly preferred PEG DMA is PEG400DMA.

[0050] And, suitable ethoxylated hydrogen compounds (or ethoxylated fatty alcohols that may be used) may be selected from those within the following structures:

[0051] [ka]

[0052] In the formula, C m can be a linear or branched alkyl or alkenyl chain, m is an integer from 1 to 30, for example, 5 to 20, n is an integer from 2 to 30, for example, 5 to 15, and R is H or C 1~6 It may be alkyl such as alkyl.

[0053] Commercially available examples of such materials include Dehydrol 100, available under the trade name Dehydrol from Cognis Deutschland GmbH & Co. KG, Dusseldorf, Germany.

[0054] Additionally, the accelerator is encompassed within the following structure:

[0055] [ka]

[0056] In the formula, R is hydrogen, C1-6 alkyl, C1-6 alkyloxy, alkylthioether, haloalkyl, carboxylic acid and esters thereof, sulfinic acid, sulfonic acid, sulfurous acid and esters thereof, phosphinic acid, phosphonic acid, phosphorous acid and esters thereof, Z is a polyether bond, n is 1 to 12, p is 1 to 3, R' is the same as R, and g is the same as n.

[0057] Particularly desirable chemicals within this class as accelerator components are:

[0058] [ka]

[0059] In the formula, the sum of n and m is 12 or more.

[0060] The accelerator should be included in the composition in an amount ranging from about 0.01% to about 10% by weight, with a range of from about 0.1 to about 0.5% by weight being preferred, and about 0.4% by weight of the total composition being particularly preferred.

[0061] Stabilizers useful in the Part A composition of the adhesive system include stabilizer packages that include free radical stabilizers, anionic stabilizers, and combinations thereof. The identity and amounts of such stabilizers are well known to those skilled in the art. See, for example, U.S. Patent Nos. 5,530,037 and 6,607,632, the disclosures of each of which are incorporated herein by reference. Commonly used free radical stabilizers include hydroquinone, while commonly used anionic stabilizers include boron trifluoride, boron trifluoride etherate, sulfur trioxide (and its hydrolysis products), and methanesulfonic acid. These anionic stabilizers may also function as or part of a cationic catalyst, as described above.

[0062] Part B Cationically curable monomers for use in the Part B composition of the adhesive system include epoxy monomers, episulfide monomers, oxetane monomers, and combinations thereof.

[0063] The epoxy monomers used in Part B of the adhesive system composition include a wide variety of epoxy monomers, some of which are aromatic, others aliphatic, and still others cycloaliphatic. Examples of such epoxy monomers include bisphenol F diglycidyl ether (and hydrogenated versions thereof), bisphenol A diglycidyl ether (and hydrogenated versions thereof), bisphenol S diglycidyl ether (and hydrogenated versions thereof), bisphenol E diglycidyl ether (and hydrogenated versions thereof), biphenyl diglycidyl ether (and hydrogenated versions thereof), 4-vinyl-1-cyclohexene diepoxide, butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, limonene diepoxide, α-pinene oxide, hexamethyl 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate ...hexylmethyl-3,4-epoxycyclohexanecarboxylate, hexamethyl 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylmethyl-3,4-ep diglycidyl ether, trimethylolpropane triglycidyl ether, aniline diglycidyl ether, diglycidyl ether of propylene glycol, cyanuric acid triglycidyl ether, orthophthalic acid diglycidyl ether, diglycidyl ester of linoleic acid dimer, dicyclopentadiene diepoxide, tetrachlorobisphenol A glycidyl ether, 1,1,1-tris(p-hydroxyphenyl)ethane glycidyl ether, tetraglycidyl ether of tetrakis(4-hydroxyphenyl)ethane, epoxy phenol novolac resin, epoxy cresol novolac resin, tetraglycidyl-4,4'-diaminodiphenylmethane, and the like.

[0064] Suitable commercially available epoxy resins include EPON 828, EPON 1001, EPON 1009, and EPON 1031 manufactured by Shell Chemical Company; DER 331, DER 332, DER 334, and DER 542 manufactured by Dow Chemical Company; GY 285 manufactured by Chiba Specialty Chemicals (Tarrytown, NY); and polyglycidyl derivatives of phenolic compounds sold under the trade name BREN-S manufactured by Nippon Kayaku Co., Ltd. (Japan); epoxidized polybutadienes such as PolyBD manufactured by Sartomer Corporation, Epolead PB3600 manufactured by Daicel Corporation, and JP-100 and JP-200 manufactured by Nippon Soda Co., Ltd.; epoxidized liquid isoprene rubbers such as KL-610, KL-613, and KL-630T manufactured by Kuraray; and epoxidized liquid polyisoprenes such as Epoxyprene 25 and Epoxyprene 50 manufactured by Sanyo Corporation. Other suitable epoxy resins include polyepoxides prepared from polyols and the like, and polyglycidyl derivatives of phenol-formaldehyde novolacs, the latter commercially available from Dow Chemical Company under the tradenames DEN 431, DEN 438, and DEN 439. Cresol analogs are also commercially available from Ciba Specialty Chemicals under the tradenames ECN 1235, ECN 1273, and ECN 1299. SU-8 is a bisphenol A-type epoxy novolac available from Resolution. Of course, cycloaliphatic epoxy resins available under the tradename Cyracure and hydrogenated bisphenol and biphenyl-type epoxy resins available under the aforementioned tradename Epalloy are also suitable for use herein.

[0065] Cycloaliphatic epoxy resins contain at least one cycloaliphatic group and at least one oxirane group (often two oxirane groups). Representative cycloaliphatic epoxy resins include 2-(3,4-epoxy)cyclohexyl-5,5-spiro-(3,4-epoxy)cyclohexane-m-dioxane, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, vinylcyclohexane dioxide, bis(3,4-epoxycyclohexylmethyl)adipate, bis(3,4-epoxy-6- Methylcyclohexylmethyl)adipate, exo-exo bis(2,3-epoxycyclopentyl) ether, endo-exo bis(2,3-epoxycyclopentyl) ether, 2,2-bis(4-(2,3-epoxypropoxy)cyclohexyl)propane, 2,6-bis(2,3-epoxypropoxycyclohexyl-p-dioxane), 2,6-bis(2,3-epoxypropoxy)norbornene, diglycidyl ether of linoleic acid dimer, limonene dioxide, α-pinene oxide, 3-vinyl Cyclohexene oxide, 3-vinylcyclohexene dioxide, epoxidized poly(1,3-butadiene-acrylonitrile), epoxidized soybean oil, epoxidized castor oil, epoxidized linseed oil, 2,2-bis(3,4-epoxycyclohexyl)propane, dicyclopentadiene dioxide, tricyclopentadiene dioxide, tetracyclopentadiene dioxide, 1,2-epoxy-6-(2,3-epoxypropoxy)hexahydro-4,7-methanoindan, p-(2,3-epoxy)cyclopentene cyclopentylphenyl-2,3-epoxypropyl ether, 1-(2,3-epoxypropoxy)phenyl-5,6-epoxyhexahydro-4,7-methanoindan, o-(2,3-epoxy)cyclopentylphenyl-2,3-epoxypropyl ether, 1,2-bis[5-(1,2-epoxy)-4,7-hexahydromethanoindanoxyl]ethane, cyclopentenylphenyl glycidyl ether, cyclohexanediol diglycidyl ether, and diglycidyl hexahydrophthalate.Siloxane-functional epoxy resins may also be utilized, such as 1,3-bis(3,4-epoxycyclohexyl-2-ethyl)-1,1,3,3-tetramethyldisiloxane and other epoxy-functional linear / cyclic siloxanes, such as those disclosed in U.S. Pat. No. 7,777,064, the disclosure of which is expressly incorporated herein by reference. In certain embodiments, the cycloaliphatic epoxy resins are 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate. Other examples of cycloaliphatic epoxies suitable for use herein include those disclosed and described in U.S. Pat. No. 6,429,281 (Dershem), the disclosure of which is expressly incorporated herein by reference.

[0066] Of course, combinations of epoxy resins are also desirable for use in the present invention.

[0067] The episulfide monomer may simply be a fully or partially sulfur-containing three-membered ring version of the base epoxy monomer.

[0068] The oxetane monomer may be selected from:

[0069] [ka]

[0070] The oxetanes labeled A to C are available from Toagosei Co., Ltd., Japan.

[0071] Vinyl ethers may also be included. The vinyl ether monomers may be selected from a number of materials, such as those commercially available under the trade name Vectomer from Bertellus Performance Materials, Inc., Greensboro, North Carolina. Examples include Vectomer Vinyl Ether 4010 [bis-(4-vinyloxybutyl) isophthalate], Vectomer Vinyl Ether 4060 [bis(4-vinyloxybutyl) adipate], and Vectomer Vinyl Ether 5015 [tris(4-vinyloxybutyl) trimellitate].

[0072] The epoxy, episulfide, oxetane, and / or vinyl ether monomers may be functionalized with one or more alkoxysilane groups. Examples of such materials include those commercially available from Gelest, Inc., Morrisville, Pennsylvania.

[0073] As noted above, additives may be included in either or both of the Part A or Part B compositions to affect various performance characteristics.

[0074] To improve the fixation time of two-component cationically curable / epoxy hybrid adhesive systems, additives including aromatic heterocycles such as pyridine, toluidine, and benzothiazole may be used, particularly disubstituted benzothiazoles in which the two substituents are alkyl, alkene, alkylbenzyl, alkylamino, alkoxy, alkylhydroxy, ether, thioalkyl, thioalkoxy, or sulfonamide groups, provided that the amide moiety of the sulfonamide group does not contain a tert-butylamino or morpholine group. More specifically, additives such as 3,5-dibromopyridine, 3,5-dichloropyridine, N,N-dimethyl-p-toluidine, 2,2-dipyridyl disulfide, 5-chloro-2-methylbenzothiazole, 2-methyl-mercaptobenzothiazole, N,N-dihydroethyl-p-toluidine, and t-butylbenzothiazole sulfonamide may be used. Phenols such as 4-methyl-2,2-ditertiarybutylphenol and 4-methoxyphenol may also be used.

[0075] These additives may be used in amounts of from greater than 0% to about 5% by weight, for example, from about 0.1 to about 2% by weight.

[0076] Optional fillers include, for example, aluminum nitride, boron nitride, silicon carbide, diamond, graphite, beryllium oxide, magnesia, titanium oxide, silica (such as fumed or fused silica), alumina, perfluorinated hydrocarbon polymers (i.e., Teflon), thermoplastic polymers, thermoplastic elastomers, mica, glass powder, etc. Preferably, the particle size of these fillers is about 20 microns or less.

[0077] With respect to silica, the silica may have an average particle size of nanoparticle size, i.e., an average particle size of 10 -9The silica nanoparticles can be pre-dispersed in epoxy resins and may be selected from those available under the trade name Nanopox from Nanoresin GmbH, Germany. Nanopox is the trade name for a family of silica nanoparticle-reinforced epoxy resins that exhibit an excellent combination of material properties. The silica phase consists of surface-modified synthetic SiO2 nanospheres with diameters less than 50 nm and an extremely narrow particle size distribution. The SiO2 nanospheres form an agglomerate-free dispersion within the epoxy resin matrix, resulting in low viscosity for resins containing up to 50 wt% silica.

[0078] A commercially available example of a Nanopox product that is particularly desirable for use herein is Nanopox A610 (a 40 wt% dispersion in a cycloaliphatic epoxy resin matrix). The particle size of the Nanopox product is believed to be between about 5 nm and about 80 nm, although the manufacturer reports it to be less than 50 nm.

[0079] The silica component should be present in an amount ranging from about 1 to about 60% by weight, for example from about 3 to about 30% by weight, and desirably from about 5 to about 20% by weight, based on the total weight of the composition.

[0080] Softeners (also called plasticizers) contemplated for use herein include branched polyalkanes or polysiloxanes capable of lowering the Tg of the composition. Examples of such softeners include polyethers, polyesters, polythiols, polysulfides, and the like. When used, softeners are typically present in an amount ranging from about 0.5% to about 30% by weight of the composition.

[0081] The flexibilizer may also be reactive, i.e., functionalized to react with the cured reaction product. In such cases, hydroxyl-functionalized resins may be used, which tend to co-react with cationically curable components such as epoxy resins, and can modify the mechanical properties of the cured product.

[0082] For example, hydroxy-functionalized aliphatic polyester diols improve the flexibility of cured compositions. One example of a commercially available diol is K-FLEX A307 from King Industries. According to the manufacturer, K-FLEX A307 is a low-viscosity, 100% solids, linear, saturated, aliphatic polyester diol with primary hydroxyl groups. K-FLEX A307 is advertised as being designed as a flexibility modifier for acrylic / isocyanate and acrylic / melamine systems. Commercial uses are advertised for automotive OEM, automotive refinish, aerospace, industrial maintenance, and plastic coatings.

[0083] Others include PolyTHF 650 / 1400 / 2000 / 2900 (sold under the trade name Terathane), polycaprolactone diols and triols (Aldrich), polydimethylsiloxane-polycaprolactone diols (such as WAX 350 OH D from Wacker), K-PURE CDR-3441, CDR-3319 (King Industries), primary or secondary hydroxyl-terminated polybutadiene / hydrogenated polybutadiene (such as Cray Valley's PolyBd / Krasol materials), hydrogenated castor oils such as Thixin R and Thixin E (Elementis Specialties), and the Polycine series (Bertellas Specialties). Other useful flexibilizers include polyurethane methacrylate-capped resins and precursors to these materials, such as 3-methyl-5-pentanediol-adipic acid copolymer.

[0084] Toughening agents particularly contemplated for use in the Part A composition include elastomeric polymers selected from elastomeric copolymers of lower alkene monomers with (i) acrylic acid esters, (ii) methacrylic acid esters, or (iii) vinyl acetate; acrylic rubbers; polyester urethanes; ethylene-vinyl acetate; fluororubbers; isoprene-acrylonitrile polymers; chlorosulfinate polyethylene; and homopolymers of polyvinyl acetate have been found to be particularly useful. [See U.S. Pat. No. 4,440,910 (O'Connor), the disclosure of which is expressly incorporated herein by reference.] In U.S. Pat. No. 4,440,910, the elastomeric polymers are described as either homopolymers of alkyl esters of acrylic acid; copolymers of alkyl or alkoxy esters of acrylic acid with another polymerizable monomer, such as a lower alkene; and copolymers of alkyl or alkoxy esters of acrylic acid. Other unsaturated monomers copolymerizable with the alkyl and alkoxy esters of acrylic acid include dienes, reactive halogen-containing unsaturated compounds, and other acrylic monomers, such as acrylamide.

[0085] For example, one group of such elastomeric polymers is the copolymer of methyl acrylate and ethylene manufactured by DuPont under the name VAMAC, such as VAMAC N123 and VAMAC B-124. VAMAC N123 and VAMAC B-124 are described by DuPont as ethylene / acrylic elastomer masterbatches. DuPont's material VAMAC G is a similar copolymer but does not contain fillers or stabilizers that provide color. VAMAC VCS rubber appears to be the base rubber from which the remaining members of the VAMAC product line are synthesized. VAMAC VCS (also known as VAMAC MR) is the reaction product of a combination of ethylene, methyl acrylate, and monomers with carboxylic acid cure sites, and, when produced, is substantially free of processing aids such as the mold release agent octadecylamine, complex organic phosphate esters and / or stearic acid, and antioxidants such as substituted diphenylamines.

[0086] Recently, DuPont has marketed VAMAC VMX1012 and VCD6200 brand name rubbers made from ethylene and methyl acrylate. VAMAC VMX1012 rubber is believed to contain little or no carboxylic acid in the polymer backbone. Like VAMAC VCS rubber, VAMAC VMX1012 and VCD6200 rubbers are substantially free of processing aids such as the aforementioned mold release agent octadecylamine, complex organic phosphate esters and / or stearic acid, and antioxidants such as substituted diphenylamines. All of these VAMAC elastomeric polymers are useful herein.

[0087] Additionally, vinylidene chloride-acrylonitrile copolymers [see U.S. Pat. No. 4,102,945 (Grieve)] and vinyl chloride / vinyl acetate copolymers [see U.S. Pat. No. 4,444,933 (Columbus)] may be included in the Part A composition, the disclosures of which are hereby incorporated by reference in their entireties.

[0088] A copolymer of polyethylene and polyvinyl acetate available from Lanxess AG under the trade name Levamelt is useful.

[0089] There are various types of Levamelt agents, including Levamelt 400, Levamelt 600, and Levamelt 900. Levamelt products vary in vinyl acetate content. For example, Levamelt 400 is an ethylene-vinyl acetate copolymer containing 40% vinyl acetate by weight. Levamelt brand products are supplied in granular form. The granules are nearly colorless and dusted with silica and talc. Levamelt brand products are composed of methylene units forming a saturated backbone with pendant acetate groups. The presence of a fully saturated backbone makes Levamelt a particularly stable polymer. It does not contain reactive double bonds that make conventional rubbers susceptible to aging reactions, ozone, and ultraviolet light. The saturated backbone is reported to provide toughness.

[0090] Interestingly, depending on the polyethylene / polyvinyl acetate ratio, the solubility of these Revamelt elastomers varies with the monomer, and with the solubility, the reinforcement capacity also varies.

[0091] Levamelt elastomers are available in pellet form and are easier to compound than other known elastomer tougheners.

[0092] Vinol brand surface coating resins, commercially available from Wacker Chemie AG (Munich, Germany), represent a broad range of vinyl chloride-derived copolymers and terpolymers recommended for use in a variety of industrial applications. The primary components of these polymers are vinyl chloride and vinyl acetate in various compositions. Terpolymers in the Vinol product line also contain carboxyl or hydroxyl groups. These vinyl chloride / vinyl acetate copolymers and terpolymers may also be used.

[0093] Vinol surface coating resins containing carboxyl groups are terpolymers of vinyl chloride, vinyl acetate, and dicarboxylic acids, with various molar compositions, degrees of polymerization, and polymerization processes. These terpolymers have been reported to exhibit excellent adhesion, especially to metal substrates.

[0094] Vinol surface coating resins containing hydroxyl groups are copolymers and terpolymers of vinyl chloride, hydroxyacrylates and dicarboxylates, with various compositions and degrees of polymerization.

[0095] Non-functional Vinol surface coating resins are copolymers of vinyl chloride and vinyl acetate with various molar compositions and degrees of polymerization.

[0096] Rubber particles, particularly those having a relatively small average particle size (e.g., less than about 500 nm or less than about 200 nm), may also be included in the Part B composition. The rubber particles may or may not have a shell, as is common in known core-shell structures. In the case of rubber particles having a core-shell structure, such particles generally have a core made of a polymeric material with elastomeric or rubber-like properties (i.e., a glass transition temperature less than about 0°C, e.g., less than about -30°C), surrounded by a shell made of a non-elastomeric polymeric material (i.e., a thermoplastic or thermoset / crosslinked polymer with a glass transition temperature greater than ambient temperature, e.g., greater than about 50°C). For example, the core may be composed of a diene homopolymer or copolymer (e.g., a homopolymer of butadiene or isoprene, or a copolymer of butadiene or isoprene with one or more ethylenically unsaturated monomers such as vinyl aromatic monomers, (meth)acrylonitrile, (meth)acrylates), and the shell may be composed of a polymer or copolymer of one or more monomers with a suitably high glass transition temperature, such as (meth)acrylates (e.g., methyl methacrylate), vinyl aromatic monomers (e.g., styrene), vinyl cyanides (e.g., acrylonitrile), unsaturated acids and anhydrides (e.g., acrylic acid), (meth)acrylamides, etc. Other rubbery polymers may also be suitable for use in the core, including polybutyl acrylate or polysiloxane elastomers (e.g., polydimethylsiloxane, especially crosslinked polydimethylsiloxane).

[0097] The rubber particles may be composed of two or more layers (e.g., a central core of one rubbery material may be surrounded by a second core of a different rubbery material, or the rubbery core may be surrounded by two shells of different compositions, or the rubber particles may have a soft-core-hard-shell-soft-hard-shell structure). In one embodiment of the present invention, the rubber particles used are composed of a core and at least two concentric shells with different chemical compositions and / or properties. Either the core or the shell, or both, may be crosslinked (e.g., ionic or covalent). The shell may be grafted to the core. The polymer constituting the shell may have one or more different types of functional groups (e.g., epoxy groups) that can interact with other components of the composition of the present invention.

[0098] Typically, the core comprises from 50 to about 95% by weight of rubber particles, and the shell comprises from about 5 to about 50% by weight of rubber particles.

[0099] The rubber particles are preferably relatively small in size. For example, the average particle size may be about 0.03 to about 2 microns, or about 0.05 to about 1 micron. The rubber particles may have an average diameter of less than about 500 nm, for example, less than about 200 nm. For example, core-shell rubber particles may have an average diameter in the range of about 25 to about 200 nm.

[0100] Methods for preparing rubber particles having a core-shell structure are known in the art and are described, for example, in U.S. Pat. Nos. 4,419,496, 4,778,851, 5,981,659, 6,111,015, 6,147,142, and 6,180,693, each of which is incorporated herein by reference in its entirety.

[0101] Rubber particles having a core-shell structure can be prepared as a masterbatch, in which the rubber particles are dispersed in one or more epoxy resins, such as diglycidyl ether of bisphenol A. For example, the rubber particles are typically prepared as an aqueous dispersion or emulsion. Such a dispersion or emulsion can be mixed with a desired epoxy resin or mixture of epoxy resins, and water and other volatile materials are removed, such as by distillation. One method for preparing such a masterbatch is described in more detail in International Patent Publication No. WO 2004 / 108825, the disclosure of which is expressly incorporated herein by reference in its entirety. For example, an aqueous latex of rubber particles can be contacted with an organic medium that is partially soluble in water, and then contacted with another organic medium that is less partially soluble in water than the first organic medium to separate the water and provide a dispersion of rubber particles in the second organic medium. This dispersion can then be mixed with a desired epoxy resin, and the volatile materials removed, such as by distillation, to provide the masterbatch.

[0102] A particularly suitable dispersion of rubber particles having a core-shell structure in an epoxy resin matrix is available from Kaneka Corporation.

[0103] For example, the core may be formed primarily from polybutadiene, polyacrylate, polybutadiene / acrylonitrile blends, polyols and / or polysiloxanes, or other monomeric materials with low glass transition temperatures, while the shell may be formed primarily from polymethyl methacrylate, polystyrene, or polyvinyl chloride, or other monomeric materials with high glass transition temperatures.

[0104] The core-shell rubber may have a particle size in the range of 0.07 to 10 μm, for example 0.1 to 5 μm.

[0105] The core-shell rubber thus produced may be dispersed in a thermosetting resin matrix, such as an epoxy matrix or a phenolic matrix. Examples of epoxy matrices include diglycidyl ethers of bisphenol A, F, or S, or biphenol, novolac epoxy, and cycloaliphatic epoxy. Examples of phenolic resins include phenoxy based on bisphenol A. The matrix material is usually liquid at room temperature.

[0106] The core-shell rubber dispersion may be present in an amount ranging from about 5 to about 50% by weight, with about 15 to about 25% by weight being preferred due to viscosity considerations.

[0107] These core-shell rubbers allow the composition to be reinforced with the uniform dispersion typically found in commercially available core-shell rubbers, and often in a predictable manner - in terms of temperature neutrality with respect to cure.

[0108] Many of the core-shell rubber structures available from Kaneka, such as those available under the trade name Kane Ace, are believed to have cores made from (meth)acrylate-butadiene-styrene copolymers, with the butadiene being the main component of the phase-separated particles dispersed in the epoxy resin. Other commercially available masterbatches of core-shell rubber particles dispersed in epoxy resin include Geniopal M23A, available from Wacker Chemie (a dispersion of 30 wt.% core-shell particles in an aromatic epoxy resin based on bisphenol A diglycidyl ether; the average diameter of the core-shell particles is approximately 100 nm and contains a crosslinked silicone elastomer core grafted with an epoxy-functional acrylate copolymer; the silicone elastomer core accounts for approximately 65 wt.% of the core-shell particles).

[0109] In the case of rubber particles that do not have such a shell, the rubber particles may be based on a core of such a structure.

[0110] The rubber particles preferably have a relatively small size. For example, the average particle size may be about 0.03 to about 2 μm, or about 0.05 to about 1 μm. In some embodiments of the present invention, the rubber particles have an average diameter of less than about 500 nm. In other embodiments, the average particle size is less than about 200 nm. For example, the rubber particles may have an average diameter in the range of about 25 to about 200 nm, or about 50 to about 150 nm.

[0111] Rubber particles are generally composed of polymeric materials having elastomeric or rubber-like properties (i.e., a glass transition temperature below about 0°C, e.g., below about -30°C). For example, the rubber particles may be composed of diene homopolymers or copolymers (e.g., homopolymers of butadiene or isoprene, copolymers of butadiene or isoprene with one or more ethylenically unsaturated monomers, such as vinyl aromatic monomers, (meth)acrylonitrile, (meth)acrylates, etc.) and polysiloxanes. The rubber particles may contain functional groups, such as carboxylate groups, hydroxyl groups, etc., and may have a linear, branched, crosslinked, random copolymer, or block copolymer structure.

[0112] For example, the rubber particles may be formed from a feedstock of primarily dienes such as butadiene, (meth)acrylates, ethylenically unsaturated nitriles such as acrylonitrile, and / or other monomers that, when polymerized or copolymerized, produce polymers or copolymers with low glass transition temperatures.

[0113] The rubber particles may be used in dry form or dispersed in a matrix, as described above.

[0114] Typically, the composition may contain from about 5 to about 35 weight percent (in one embodiment, from about 15 to about 30 weight percent) of rubber particles.

[0115] Combinations of different rubber particles may be advantageously used in the present invention, which may differ, for example, in particle size, the glass transition temperature of each material, whether, to what extent, and with what degree the materials are functionalized, and whether and how they are surface treated.

[0116] A portion of the rubber particles may be provided in the form of a masterbatch in which the particles are stably dispersed in an epoxy resin matrix, while another portion may be provided in the adhesive composition in the form of a dry powder (i.e., without epoxy resin or other matrix materials). For example, the adhesive composition may be prepared using both a first type of rubber particles in dry powder form having an average particle size of about 0.1 to about 0.5 μm and a second type of rubber particles stably dispersed in a matrix of liquid bisphenol A diglycidyl ether at a concentration of about 5 to about 50 wt % and having an average particle size of about 25 to about 200 nm. The weight ratio of the first type to the second type of rubber particles may be, for example, about 1.5:1 to about 0.3:1.

[0117] The chemical composition of the rubber particles may be essentially uniform throughout each particle. However, to enhance the dispersion of the rubber particles in the adhesive composition, the outer surface of the particles may be modified by reaction with a coupling agent, an oxidizing agent, etc. (e.g., to reduce the agglomeration of the rubber particles and reduce the tendency of the rubber particles to settle out of the adhesive composition). Modification of the rubber particle surface may enhance adhesion of the epoxy resin matrix to the rubber particles when the adhesive is cured. Alternatively, the rubber particles may be irradiated to vary the degree of crosslinking of the polymers that make up the rubber particles in different regions of the particle. For example, the rubber particles may be treated with gamma radiation to cause the rubber to be more highly crosslinked near the surface of the particle than in the center of the particle.

[0118] Rubber particles suitable for use in the present invention are commercially available. For example, rubber particles supplied by Eriochem Co., Ltd. may be used, such as NEP R0401 and NEP R401S (both based on acrylonitrile / butadiene copolymer), NEP R0501 (based on carboxylated acrylonitrile / butadiene copolymer; CAS number 9010-81-5), NEP R0601A (based on hydroxy-terminated polydimethylsiloxane; CAS number 70131-67-8), and NEP R0701 and NEP0701S (based on butadiene / styrene / 2-vinylpyridine copolymer; CAS number 25053-48-9). Others are available under the Paraloid trade name, such as Paraloid 2314, Paraloid 2300, and Paraloid 2600, from The Dow Chemical Company (Philadelphia, Pennsylvania), and under the Staphyloid trade name, such as Staphyloid AC-3832, from Ganz Chemical Co., Ltd. (Osaka, Japan).

[0119] Rubber particles that have been treated with reactive gases or other reagents to modify the outer surface of the particles, for example, to generate polar groups (e.g., hydroxyl groups, carboxylic acid groups) on the particle surface, are also suitable for use in the present invention. Exemplary reactive gases include, for example, ozone, Cl, F, O, SO, and oxidizing gases. Methods for modifying the surface of rubber particles using such reagents are known in the art and are 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 incorporated herein by reference in its entirety. Suitable surface-modified rubber particles are also commercially available, such as those sold by Exusia under the trade name Vistamer.

[0120] If the rubber particles are initially provided in a dry state, it may be advantageous to ensure that such particles are well dispersed in the adhesive composition before curing the adhesive composition. That is, agglomerates of rubber particles are preferably broken down to provide individual rubber particles, which may be achieved by intimately and thoroughly mixing the dry rubber particles with the other components of the adhesive composition. For example, the dry rubber particles may be mixed with an epoxy resin and milled or melt-blended for a time effective to essentially completely disperse the rubber particles and break down agglomerates of the rubber particles.

[0121] Additionally, Nanoresins offers commercial products under the trade names Arbidur (epoxy resins containing core-shell silicone rubber particles; e.g., EP2240, EP2240A, EP5340); Arbiflex (epoxy-siloxane block copolymer resins); and Arbipox (epoxy resins containing epoxy-nitrile butadiene rubber adducts). Many of these types of tougheners are also useful in Part B of the composition. One example of these core-shell rubber particles is commercially available from Cochemtura, Inc. (Middlebury, Connecticut) under the trade name Brendex. In particular, it is Brendex 338, an ultra-high rubber ABS impact modifier based on polybutadiene rubber.

[0122] Thickeners or viscosity modifiers are also useful. Useful materials in this regard include polyvinyl butyral resins sold under the trade name Mowital (Kuraray Co., Ltd.), such as Mowital B30T, B60T, B20H, B30H, B45H, B60H, B30HH, and B60HH.

[0123] Other additives may also be included in the Part A composition. For example, the Part A composition may include phosphoric acid. When included at levels ranging from about 50 ppm to about 1,000 ppm, e.g., from about 100 to about 500 ppm, and applied to at least one aluminum substrate to be bonded in an adhesive assembly, improved strength and strength retention may be observed. More specifically, humidity, heat aging, and solvent immersion tests have shown that the addition of phosphoric acid to the two-component cyanoacrylate / cationic curable adhesive system of the present invention may dramatically improve durable adhesion to both metals and plastics, especially aluminum.

[0124] In another aspect, the present invention provides a method for producing a method of manufacturing a semiconductor device comprising: applying a cyanoacrylate composition to at least one substrate in water; The cyanoacrylate composition comprises: a first part comprising a cyanoacrylate component and a cationic catalyst; a cationically curable component such as an epoxy component, an episulfide component, an oxetane component, and combinations thereof; and a second part comprising an initiator component; curing the composition in water; The present invention relates to a method for bonding substrates underwater, comprising:

[0125] The cyanoacrylate composition may be applied in a ratio of part 1 to part 2 of the cyanoacrylate composition ranging from about 1:1 to about 10:1, such as 2:1, or 3:1, or 4:1, or 5:1, or 6:1, or 7:1, or 8:1, or 9:1.

[0126] The cyanoacrylate composition may be applied in a ratio of part 1 to part 2 of about 1:1.

[0127] A method for bonding underwater substrates may include exposing the composition to water for up to 45 seconds before joining the surface of the second substrate with the coated surface of the first substrate. This is sometimes referred to as the open time of the composition. The composition may have a good open time of up to 90 seconds, e.g., up to 60 seconds, e.g., up to 45 seconds. A good open time is beneficial because it allows time for the substrates to be properly assembled before the composition hardens. A good open time allows time for assembly, so that the substrates can be assembled in the correct configuration. This composition has a good open time, allowing the nozzle (the nozzle used to dispense the composition) to be replaced underwater without the composition hardening. This composition may form a film on top of the film, but the majority of the film does not harden, resulting in a good open time.

[0128] In the method of bonding underwater substrates, the composition does not mix with water, for example, in the water column, and does not disperse in water. The physical properties of the composition, such as viscosity, are such that the composition does not mix with water and remains where it is applied. The outermost layer of the composition may harden to form a film, preventing most of the composition from contacting water. In this regard, the entire composition may harden after the two substrates are joined together.

[0129] The method for bonding underwater substrates shall have a shear strength of at least 0.2 N / mm after 24 hours of cure, measured in accordance with ASTM D1002. 2 , for example, 0.4 N / mm after 168 hours of curing 2 For example, if at least one substrate comprises calcium carbonate, the adhesive may be formed in whole or in part from calcium carbonate.

[0130] In a method for bonding underwater substrates, for example, when at least one substrate is formed of metal, e.g., steel, the composition has a shear strength measured in accordance with ASTM D1002 of at least 0.2 N / mm after 24 hours of cure. 2 , for example, 0.4 N / mm after 168 hours of curing2 Form a bond.

[0131] In the methods of the present invention, one or both substrates may be naturally occurring and / or man-made.

[0132] Naturally occurring substrates include coral substrates, such as coral reefs. Coral reefs are formed by colonies of coral polyps. Calcium carbonate substrates may be adhered by the methods of the present invention. These substrates include coral substrates, including the calcium carbonate skeleton of the coral substrate. For example, the methods of the present invention may be used to repair damage to coral formations and / or to add coral material to coral formations.

[0133] In methods for bonding underwater substrates, one or both substrates may be metal, for example, one or both substrates may be steel.

[0134] In the method of bonding underwater substrates, at least one substrate may comprise a material selected from the group including: steel, aluminum, wood, fiberglass, building materials including aggregates, sand, concrete / cement materials including ferrocement, fiber reinforced plastics.

[0135] Suitably, both substrates may independently comprise a material selected from the group including steel, aluminium, wood, fibreglass, building materials including aggregates, sand, concrete / cement materials including ferrocement, fibre reinforced plastics.

[0136] In the method for bonding underwater substrates, at least one substrate may be a watercraft, such as a boat or watercraft, or a portion thereof. The method may be used to secure items to the boat or watercraft. For example, it may be used to attach sensors, install replacement parts, or even perform repairs on the boat or watercraft. Using the method of the present invention, this can be done without having to return to land and remove the boat or watercraft from the water.

[0137] In methods for bonding underwater substrates, at least one substrate may be part of a structure located or extending underwater, such as a bridge, oil or gas rig, pipeline, dam, wind turbine, etc. Because such structures cannot be removed from the water, it is beneficial to be able to attach items such as accessories, sensors, or replacement parts, or to perform repairs underwater.

[0138] In a method for adhering underwater substrates, one or both substrates may comprise calcium carbonate, e.g., may be formed wholly or partially of calcium carbonate, e.g., one or both substrates are shells, e.g., one or both substrates are scleractinia shells.

[0139] In methods for bonding underwater substrates, the nozzle life may be at least 4 minutes, e.g., at least 5 minutes. The dispensing nozzle has good nozzle life because the composition does not prematurely harden and clog the nozzle. This is surprising because compositions containing cyanoacrylates typically harden rapidly when exposed to moisture, such as in water. The longer nozzle life allows for more application of the composition before the nozzle needs to be replaced.

[0140] The method for bonding underwater substrates may be carried out in water containing various amounts of salt and / or minerals. For example, the method may be carried out in distilled water or treated water, such as a public water supply. The method may be carried out in fresh water, such as a well, river, or lake. The method may be carried out in salt water, such as seawater, e.g., water having a salinity of about 30 g / L to about 50 g / L.

[0141] The method of adhering a substrate in water may be carried out in water having a pH in the range of about 6 to about 9, for example, about 6.5 to about 8, or about 7.5 to about 8.5.

[0142] In another aspect, the invention relates to an assembly comprising two underwater substrates bonded by the method of the invention. DETAILED DESCRIPTION OF THE INVENTION

[0143] A method for bonding underwater substrates includes applying a composition disclosed herein to at least one substrate underwater and allowing the composition to cure.

[0144] The nozzle life may be at least 4 minutes, for example at least 5 minutes. This means that the composition does not harden within this time in the nozzle used to dispense the composition while it is being applied. A thin layer of the composition may harden at the tip of the nozzle where the composition comes into contact with water. The majority of the composition in the nozzle body that does not come into contact with water remains unhardened. Because the composition has good nozzle life in water, it is still possible to dispense the composition from the nozzle.

[0145] Advantageously, the composition may be exposed to water for up to 45 seconds before joining the surface of the second substrate with the coated surface of the first substrate, and the composition remains uncured and capable of forming a bond between the substrates.

[0146] The method involves curing the composition in water. The composition is not removed from the water for curing. Upon curing, the bond formed is strong. Upon curing, the bond formed maintains its strength over time, making the method suitable for bonding substrates over long periods of time. The bond is at least 0.2 N / mm after 24 hours of cure, as measured according to ASTM D1002. 2 , for example, 0.4 N / mm after 168 hours of curing 2 This bond strength can be achieved even with difficult-to-bond materials such as calcium carbonate. Allowing calcium carbonate to bond for extended periods, e.g., 168 hours, makes the method suitable for reef applications, e.g., coral transplantation. The bond strength achieved can be greater than the breaking point of the calcium carbonate, meaning that the calcium carbonate breaks before the bond breaks. The bond should have a shear strength of at least 0.2 N / mm after 24 hours of cure, as measured according to ASTM D1002. 2, for example, 0.4 N / mm after 168 hours of curing 2 The bond may have a shear strength of at least 0.2 N / mm after 24 hours of cure, as measured according to ASTM D1002. Because the substrate will not fail before the bond fails, it is possible to achieve bonds with higher shear strength on substrates with higher shear strength. For example, metals such as steel, e.g., grit blasted mild steel (GBMS), have higher shear strengths than bonds formed by this method, with a shear strength of at least 0.2 N / mm after 24 hours of cure, as measured according to ASTM D1002. 2 , for example, 0.4 N / mm after 168 hours of curing 2 The shear strength may be [Example]

[0147] Briefly, the substrates to be tested were bonded as follows: The substrates were submerged in water so that the water contacted all surfaces of the substrate; The substrates were completely submerged; and The substrates were not removed from the water before applying the adhesive.

[0148] The components of representative compositions of the present invention are numbered 1 through 5 and are identified in Table 1. Each column lists the weight percent amount of each component for each of the five compositions.

[0149] [Table 1]

[0150] Composition No. 3, having the ingredients / amounts listed in the columns of Table 1 above, was dispensed from a container (at a 1:1 mix ratio) and applied to a first substrate. A second substrate was overlapped by 1 inch (2.54 cm), and the substrates were clamped together to allow the adhesive to cure and form a bond between the substrates. The open time was the time from dispensing from the container to overlapping the second substrate. The adhesive was applied and cured underwater. For dry substrate testing, the substrate was not submerged. The substrates were dry, i.e., free of surface moisture, when the adhesive was applied and when it cured. The shear strength of the bond was measured according to ASTM D1002.

[0151] The substrates tested were grit blasted mild steel (GBMS), calcium carbonate.

[0152] result The GBMS substrates were bonded with an open time of 0 seconds; that is, once the composition was applied to the substrates, the substrates were immediately bonded. The substrates were not removed from the water while the adhesive was curing. The bond was cured while fully submerged. The results are shown in Table 2. The strength achieved allowed the bonded substrates to be handled without breaking the bond. After 24 hours of curing, the bond strength was maintained as shown in Table 2. After 168 hours of curing, the bond strength was maintained as shown in Table 2.

[0153] The calcium carbonate substrates were bonded with an open time of 0 seconds. The substrates were not removed from the water while the adhesive was curing. The adhesive cured while fully submerged in water. As shown in Table 2, the adhesive achieved good handling strength after curing for 5 minutes. This strength allows the bonded substrates to be handled without breaking the bond. After 24 hours of curing, the adhesive strength was maintained as shown in Table 2. After 168 hours of curing, the adhesive strength was maintained as shown in Table 2.

[0154] [Table 2]

[0155] The nozzle life of the package when the adhesive is placed in water is at least 5 minutes if the adhesive is dispensed at intervals of 2 minutes or less. Table 3 shows that the adhesive composition dispensed easily and did not clog the nozzle even after 5 minutes. The adhesive composition extruded easily from the nozzle at 0 minutes, i.e., when the nozzle was first exposed to water. After 1 minute of exposure to water, the composition extruded easily from the nozzle. Dispensing of the composition was not hindered even when the nozzle was underwater. After an additional minute in water (2 minutes), the composition dispensed easily from the nozzle. After an additional minute in water (3 minutes), the composition dispensed easily from the nozzle. After an additional 2 minutes in water (5 minutes), the surface of the composition began to harden, requiring the tip of the nozzle to be cleaned. The composition did not harden completely; only a thin layer of the composition began to harden. Since no hardening occurred, the tip of the nozzle was cleaned to remove the hardened layer, and the composition was then easily dispensed from the nozzle.

[0156] [Table 3]

[0157] As used herein in relation to the present invention, the words "comprise" and "have / comprise" are used to specify the presence of stated features, integers, steps or components, but do not exclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0158] It will be appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.

Claims

1. applying a cyanoacrylate composition to at least one substrate in water; The cyanoacrylate composition comprises: (a) a first part comprising a cyanoacrylate component and a cationic catalyst; (b) a cationically curable component, such as an epoxy component, an episulfide component, an oxetane component, and combinations thereof; and and a second part comprising an initiator component. curing the composition in water; A method for bonding underwater substrates, comprising:

2. The cyanoacrylate component of the cyanoacrylate composition has the structure H ２ selected from materials having the formula C=C(CN)-COOR, where R is C １～１５ Alkyl group, C ２～１５ Alkoxyalkyl group, C ３～１５ Cycloalkyl group, C ２～１５ Alkenyl group, C ６～１５ Aralkyl group, C ５～１５ Aryl group, C ３～１５ Allyl group, and C １～１５ The method of claim 1, wherein the cyanoacrylate component is selected from haloalkyl groups, for example, the cyanoacrylate component comprises ethyl-2-cyanoacrylate.

3. 3. The method of claim 1 or 2, wherein the cationic catalyst comprises a lithium salt, a Group II metal salt, and a non-nucleophilic metal.

4. 4. The method of claim 3, wherein the cationic catalyst is a non-nucleophilic catalyst having a pH of less than 1.0 when measured as a 10% by weight solution in water.

5. 5. The method of claim 1, wherein the cationic catalyst is one selected from the group consisting of fluoroboric acid, fluoroarsenic acid, fluoroantimonic acid, and fluorophosphoric acid; lithium tetrafluoroborate, calcium ditetrafluoroborate, magnesium ditetrafluoroborate, lithium hexafluorophosphate, calcium dihexafluorophosphate, magnesium dihexafluorophosphate, lithium hexafluoroantimonate, and lithium hexafluoroarsenate; lanthanide triflate salts, aryliodonium salts, arylsulfonium salts, lanthanum triflate, ytterbium triflate, trimethoxyboroxine, trimethoxyboroxine-aluminum acetylacetonate, amine-boron trihalide complexes, quaternary ammonium salts, quaternary phosphonium salts, triarylsulfonium salts, diaryliodonium salts, and diazonium salts; trialkoxyboroxine curing agents; and combinations thereof.

6. The method of any one of claims 1 to 5, wherein the cationically curable component is selected from an epoxy component, an episulfide component, an oxetane component, a vinyl ether component, and combinations thereof.

7. 7. The method of any one of claims 1 to 6, wherein the cationically curable component is an epoxy component selected from the group consisting of cycloaliphatic epoxies, aromatic epoxies, aliphatic epoxies, and hydrogenated aromatic epoxies.

8. 8. The method of any one of claims 1 to 7, wherein the cationically curable component is an epoxy component, and the epoxy component comprises one selected from the group consisting of epoxy-functionalized hydrogenated bisphenol-A, bisphenol-F, bisphenol-E, bisphenol-S, and biphenyl.

9. 9. The method of any one of claims 1 to 8, wherein the first part further comprises phosphoric acid.

10. The method of any one of claims 1 to 9, wherein the second part further comprises at least one of a plasticizer, a filler, and a reinforcing agent.

11. 11. The method of claim 10, wherein the toughening agent is one selected from the group consisting of: (1) (a) a reaction product of a combination of ethylene, methyl acrylate, and a monomer having a carboxylic acid cure site; (2) (b) a dipolymer of ethylene and methyl acrylate; (3) a combination of (a) and (b); (4) a vinylidene chloride-acrylonitrile copolymer; (5) a vinyl chloride / vinyl acetate copolymer; (6) a copolymer of polyethylene and polyvinyl acetate; and combinations thereof.

12. The method of any one of claims 1 to 11, wherein the first part and the second part are present in a volume ratio of about 1:

1.

13. The method of any one of claims 1 to 12, wherein the initiator component is one selected from the group consisting of heterocycles, pyridines, benzothiazoles, toluidines, and phenols.

14. The method of any one of claims 1 to 13, wherein the initiator component is one selected from the group consisting of 3,5-dibromopyridine, 3,5-dichloropyridine, N,N-dimethyl-p-toluidine, 2,2-dipyridyl disulfide, 5-chloro-2-methylbenzothiazole, 2-methyl-mercaptobenzothiazole, N,N-dihydroethyl-p-toluidine, t-butylbenzothiazole sulfonamide, 4-methyl-2,2-ditertiarybutylphenol, and 4-methoxyphenol.

15. A method according to any preceding claim, wherein one or both of the substrates is metallic, for example one or both of the substrates is steel.

16. 16. The method of any one of claims 1 to 15, wherein one or both of the substrates comprises calcium carbonate, for example one or both of the substrates is a shell, for example one or both of the substrates is a scleractinia shell.

17. A method according to any preceding claim, wherein the nozzle has a life of at least 4 minutes, such as at least 5 minutes.

18. An assembly comprising two underwater substrates bonded by the method of any one of claims 1 to 14.

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