Moisture-curable adhesive composition

Abstract

Disclosed herein is a wet curable composition, an application method, and a substrate comprising the composition. In some embodiments, the curable composition comprises: a component (A) comprising an organic polymer containing a reactive silicon group represented by the general formula (1); a component (B) comprising an organic polymer having a viscosity of less than 10,000 cP at 23°C, the organic polymer containing a reactive silicon group represented by the general formula (2); and a component (C) comprising a polyolefin polymer. The wet curable composition has general adhesion to anti-adhesive substrates such as PVC, EPDM, and TPO. The substrate can be a smooth back or velvet back substrate.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 811,640, filed February 28, 2019, the disclosure of which is incorporated herein by reference. Invention Field

[0003] This invention relates to a moisture-curable adhesive composition comprising an organic polymer containing reactive silicon groups. In particular, this invention relates to a moisture-curable adhesive composition with general adhesion to substrates such as polyvinyl chloride (hereinafter defined as "PVC"), ethylene propylene diene rubber (hereinafter "EPDM"), and thermoplastic polyolefins (hereinafter "TPO"), and its uses. Background Technology

[0004] In recent years, research has been conducted on improving adhesion to non-adhesive substrates by adding thermoplastic elastomers to organic polymers containing reactive silicon groups (e.g., Japanese Patent No. 4485246B2 of Kanegafuchi Chemical Industry Co., Ltd. and Kaneka Texas Corp.).

[0005] Kaneka Corp.’s U.S. Patent No. 7,759,425 describes a wet-curing formulation that improves adhesion to TPO by incorporating tackifiers and chlorinated polyolefins into an organic polymer containing reactive silicon groups.

[0006] Chemlink, Inc.’s U.S. Patent No. 7,767,308 describes the use of organic polymers containing reactive silicon groups, phenolic tackifiers, and silane adhesive promoters to bond with rubber materials.

[0007] Unfortunately, these formulations fail to achieve universally good adhesion on various substrates, including EPDM, PVC, and TPO. Achieving adhesion on smooth-backed versions of these substrates is particularly difficult compared to versions with a velvet back that incorporate additional surface treatments to improve adhesion. Solvent-based adhesives remain widely available on the market, offering excellent adhesion on these difficult-to-adhere plastic substrates. However, solvent-based systems require solvent evaporation before the two substrates can be bonded together. This affects air quality and prolongs construction time. Consequently, worker safety and health issues arise during manufacturing, and in cases where structures are occupied, normal construction must be suspended due to toxic fumes. Solvent-based systems can also lead to significant environmental burdens or fire hazards. There is a need to develop an adhesive formulation that is either solvent-free or contains minimal solvent, yet still provides universally good adhesion to both smooth-backed and velvet-backed variations of substrates such as EPDM, PVC, and TPO. Summary of the Invention

[0008] This document discloses a moisture-curable composition. In some embodiments, it is a moisture-curable composition comprising the following:

[0009] Component (A), an organic polymer with a viscosity greater than 20,000 cP at 23°C and containing reactive silicon groups represented by the following general formula (1):

[0010] —Si(R 1 3-a )X a (1)

[0011] Where R 1 Represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms.

[0012] X represents a hydrolyzable group, wherein when two or more X's are present, each X's can be the same or different, and

[0013] 'a' represents 1, 2, or 3.

[0014] The condition is that when a is 1, each R 1 They can be the same or different, and

[0015] The condition is that when a is 2 or 3, each X can be the same or different;

[0016] Component (B), an organic polymer with a viscosity of less than 10,000 cP at 23°C and containing reactive silicon groups represented by the following general formula (2):

[0017] —Si(R 2 3-b)X b (2)

[0018] Where R 2 Represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms.

[0019] X represents a hydrolyzable group, wherein when two or more X's are present, each X's can be the same or different, and

[0020] b represents 1, 2, or 3.

[0021] The condition is that when b is 1, each R 2 They can be the same or different, and

[0022] The condition is that when b is 2 or 3, each X can be the same or different; and

[0023] Components (C) containing polyolefin polymers.

[0024] In some embodiments, X in general formulas (1) and (2) is represented by -OR, where R is an alkyl group having 1 to 2 carbon atoms.

[0025] In some implementations, the organic polymer of component (A and / or B) may have a polyoxypropylene backbone.

[0026] In some embodiments, the organic polymer of component (A and / or B) may include groups represented by the following general formula (3):

[0027] –NR 3 C(=O)– (3)

[0028] Where R 3 Represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms.

[0029] In some implementations, the polyolefin polymer of component (C) may be a chlorinated polyolefin polymer.

[0030] In some embodiments, the polyolefin polymer of component (C) may be a polymer modified with acrylic acid, maleic acid and / or maleic anhydride.

[0031] In some implementations, component (C) may include a solvent or a plasticizer.

[0032] In some embodiments, the wet-curable composition comprises:

[0033] Component (A), an organic polymer containing reactive silicon groups represented by the following general formula (1):

[0034] —Si(R 1 3-a )X a (1)

[0035] Where R 1 Represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms.

[0036] X represents a hydrolyzable group, wherein when two or more X's are present, each X's can be the same or different, and

[0037] 'a' represents 1, 2, or 3.

[0038] The condition is that when a is 1, each R 1 They can be the same or different, and

[0039] The condition is that when a is 2 or 3, each X can be the same or different;

[0040] Component (B), an organic polymer with a viscosity of less than 5,000 cP at 23°C and containing reactive silicon groups represented by the following general formula (2):

[0041] —Si(R 2 3-b )X b (2)

[0042] Where R 2 Represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms.

[0043] X represents a hydrolyzable group, wherein when two or more X's are present, each X's can be the same or different, and

[0044] b represents 1, 2, or 3.

[0045] The condition is that when b is 1, each R 2 They can be the same or different, and

[0046] The condition is that when b is 2 or 3, each X can be the same or different; and

[0047] Components (C) containing polyolefin polymers.

[0048] In some embodiments, X in general formulas (1) and (2) is represented by -OR, where R is an alkyl group having 1 to 2 carbon atoms. In some embodiments, the organic polymer of component (A and / or B) may have a polyoxypropylene backbone.

[0049] In some embodiments, the organic polymer of component (A and / or B) may include groups represented by the following general formula (3):

[0050] –NR 3 C(=O)– (3)

[0051] Where R 3 Represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms.

[0052] In some implementations, the polyolefin polymer of component (C) may be a chlorinated polyolefin polymer.

[0053] In some embodiments, the polyolefin polymer of component (C) may be a polymer modified with acrylic acid, maleic acid and / or maleic anhydride.

[0054] In some implementations, component (C) may include a solvent or a plasticizer. Detailed Implementation

[0055] One object of the present invention is to provide a moisture-curable adhesive composition that provides excellent adhesion to any surface, including anti-adhesive surfaces such as EPDM, PVC, and TPO, without the need for primer application to smooth and textured back surfaces of these substrates. An exemplary EPDM substrate may include Carlisle. EPDM, Carlisle EPDM, Johns Manville EPDM NR / R, Firestone RubberGard™ EPDM, Firestone Ecowhite™ EPDM, and / or Firestone Fullforce™ EPDM. Exemplary PVC substrates may include GAF. PVC, GAF PVC XK, Carlisle Sure- PVC, Carlisle KEE HP, Johns Manville PVC SD Plus, Johns Manville PVC with KEE, and / or Sika Sarnafil PVC. Exemplary TPO substrates may include Firestone UltraPly™ TPO, Firestone UltraPly™ TPO XR, Firestone UltraPly™ TPO Flex Adhered, Firestone Platinum TPO, and GAF. TPO, GAF EverGuard TPO, GAF TPO Ultra and / or Carlisle Sure-Weld TPO.

[0056] The wettable curable composition comprises component (A), said component (A) containing an organic polymer with reactive silicon groups represented by the following general formula (1):

[0057] —Si(R 1 3-a )X a (1)

[0058] Where R 1 X represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, X represents a hydrolyzable group, and a is an integer from 1 to 3, provided that when a is 1, each R 1 They can be the same or different, and the condition is that when a is 2 or 3, each X can be the same or different.

[0059] In some implementations, X stands for -OR, where R is an alkyl group having 1 to 2 carbon atoms.

[0060] In some embodiments, the organic polymer of component (A) has a viscosity greater than 20,000 cP at 23°C.

[0061] The curable composition comprises a component (B) having an organic polymer having a viscosity of less than 10,000 cP at 23°C and containing reactive silicon groups represented by general formula (2):

[0062] —Si(R 2 3-b )X b (2)

[0063] Where R 2 X represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, X represents a hydrolyzable group, and b is an integer from 1 to 3, provided that when b is 1, each R 2 They can be the same or different, and when b is 2 or 3, each X can be the same or different.

[0064] In some implementations, X stands for -OR, where R is an alkyl group having 1 to 2 carbon atoms.

[0065] In some embodiments, the organic polymer of component (B) has a viscosity greater than 5,000 cP at 23°C.

[0066] The curable composition contains a component (C) having a polyolefin polymer.

[0067] When X in general formulas (1) and (2) is a hydrolyzable group, X is not particularly limited, as long as X is a known hydrolyzable group. Specific examples include hydrogen and halogen atoms; and alkoxy, acyloxy, ketooxime ester, amino, amide, acid amide, aminooxy, mercapto, and alkenoxy groups. Among these, alkoxy groups such as methoxy, ethoxy, propoxy, and isopropoxy are particularly preferred because their hydrolytic properties are mild, making the compound easy to handle.

[0068] R in general formula (1) 1 And R in general formula (2) 2 There are no particular limitations, and the group may be an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. Specific examples include alkyl groups such as methyl, ethyl, propyl, and isopropyl, aryl groups such as phenyl, and aralkyl groups such as benzyl. Of these groups, methyl is particularly preferred from the viewpoint of availability of raw materials.

[0069] There are no particular restrictions on the specific structure of the reactive silicon group represented by general formula (1) or general formula (2), as long as the structure is known. From the viewpoint of reactivity and availability, trimethoxysilyl, methyldimethoxysilyl, triethoxysilyl and methyldiethoxysilyl are particularly preferred.

[0070] In each of chemical formulas (1) and (2), one or more reactive silicon groups may be used, or in combination.

[0071] Reactive silicon groups are introduced into the polyoxyethylene polymer backbone of component (A and / or B) using known methods. Examples include the following methods:

[0072] (i) A polyoxyethylene polymer having a functional group such as a hydroxyl group is reacted with an organic compound having an active group exhibiting reactivity with that functional group and having an unsaturated group, thereby producing a polyoxyethylene polymer having an unsaturated group. Alternatively, for example, when an epoxide undergoes ring-opening polymerization to produce a polyoxyethylene polymer, an epoxide containing an unsaturated group is ring-opened copolymerized with it to produce a polyoxyethylene polymer having an unsaturated group. In this manner, monomers having unsaturated groups independent of any polymerization reaction are copolymerized, thereby producing an organic polymer having an unsaturated group. Next, a hydrosilane having a reactive silane group is reacted onto the resulting reaction product, thereby hydrosilylating the reaction product.

[0073] In order to introduce reactive silicon groups at a high introduction rate in method (i), it is preferable to add a hydrosilane compound to a group containing CH2═C(R) 4 )—CH2— or CH(R 4 )═CH—CH2—(where R 4 The introduction is achieved in organic polymers containing unsaturated groups (representing hydrogen or hydrocarbon groups having 1 to 10 carbon atoms). More preferably, R 4 It is hydrogen or methyl. To set the introduction rate of reactive silicon groups to 85% or higher, R... 4 The methyl group is particularly important.

[0074] Specific examples of hydrosilane compounds used in method (i) include halogenated silanes such as trichlorosilane, methyldichlorosilane, dimethylchlorosilane, and phenyldichlorosilane; alkoxysilanes such as trimethoxysilane, triethoxysilane, methyldiethoxysilane, methyldimethoxysilane, and phenyldimethoxysilane; acyloxysilanes such as methyldiacetoxysilane and phenyldiacetoxysilane; and ketooxime ester silanes such as bis(dimethyl ketooxime)methylsilane and bis(cyclohexyl ketooxime)methylsilane. However, the hydrosilane compounds are not limited thereto. Among these compounds, halogenated silanes and alkoxysilanes are particularly preferred, and alkoxysilanes are most preferred because the compositions obtained from them have mild hydrolytic properties, making the compositions easy to handle.

[0075] (ii) Reacting a compound having thiol and reactive silicon groups with a polyoxyethylene polymer containing unsaturated groups obtained in the same manner as in method (i).

[0076] Synthetic method (ii) is, for example, a method of introducing a compound having a thiol group and a reactive silicon group into the unsaturated bond portion of an organic polymer via a radical addition reaction in the presence of a radical initiator and / or a radical generating source. However, this method is not particularly limited. Specific examples of compounds having a thiol group and a reactive silicon group include, but are not limited to, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropyltriethoxysilane, and γ-mercaptopropylmethyldiethoxysilane.

[0077] (iii) Reacting a polyoxyethylene polymer having functional groups such as hydroxyl, epoxy, or isocyanate with a compound having a functional group reactive with the former and having a reactive silicon group. The functional groups of the compound are not limited, but isocyanate groups or amino groups are preferred. Isocyanate groups are particularly preferred.

[0078] In a particular alternative to synthetic method (iii), the method of reacting a polyoxyethylene polymer having hydroxyl groups at its ends with a compound having isocyanate groups and reactive silicon groups is, for example, the method described in Japanese Patent Application Publication No. 3-47825. However, this method is not particularly limited. Specific examples of compounds having isocyanate groups and reactive silicon groups include γ-isocyanate propyltrimethoxysilane, γ-isocyanate propylmethyldimethoxysilane, γ-isocyanate propyltriethoxysilane, γ-isocyanate propylmethyldiethoxysilane, α-isocyanate methyldimethoxymethylsilane, and α-isocyanate methyltrimethoxysilane. However, the compound is not limited thereto.

[0079] Of the methods described above, method (i) or (iii) is preferred because the polymer obtained by method (ii) emits a strong odor based on mercaptosilane. Regarding the method of introducing reactive silicon groups, the organic polymer with reactive silicon groups obtained by method (i) is preferred over the polymer obtained by method (iii) because the polymer becomes a composition with low viscosity and good processability. On the other hand, method (iii) is preferred because the introduction of silanes into the hydroxyl-containing polymer can be achieved in only one step, allowing for the preparation of components (A) and (B) with good productivity.

[0080] In a particular alternative to method (iii), a preferred method is to react a polyoxyolefin polymer having hydroxyl groups at its ends with a compound having isocyanate groups and reactive silicon groups, because a high conversion rate is achieved with a relatively short reaction time. The olefin polymer obtained by such a reaction is a polymer having reactive silicon groups and groups represented by the following general formula (3):

[0081] —NR 3 —C(═O)—(3)

[0082] Where R 3 Represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms.

[0083] Component (A) having a group represented by general formula (1) and component (B) having a group represented by general formula (2) can also be obtained by methods other than those described above. Specifically, compounds obtained by chain extension reaction of polyols with diisocyanate compounds such as aromatic polyisocyanates (e.g., toluene(methylphenylene) diisocyanate, diphenylmethane diisocyanate, or xylene diisocyanate) or aliphatic polyisocyanates (e.g., isophorone diisocyanate or hexamethylene diisocyanate) are compounds having a group of general formula (3), regardless of the method of introducing reactive silicon groups.

[0084] Component (A) can be linear or branched, and its number average molecular weight is preferably 3,000 or greater, and practically 100,000 or less for polystyrene based on gel permeation chromatography (GPC). More preferably, the number average molecular weight is between 10,000 or greater and 50,000 or less. Molecular weight is measured using an HLC-8120 GPC (TOSOH CORPORATION) as a solution delivery system, a TSK-GEL H-type column (TOSOH CORPORATION), and THF solvent.

[0085] Component (B) can be linear or branched, and its number-average molecular weight is preferably 500 or greater, and practically 15,000 or less for polystyrene based on gel permeation chromatography (GPC). More preferably, the number-average molecular weight is between 1,000 or greater and 10,000 or less. Molecular weight is measured using an HLC-8120 GPC (TOSOH CORPORATION) as a solution delivery system, a TSK-GEL H-type column (TOSOH CORPORATION), and THF solvent.

[0086] The reactive silicon groups of components (A) and (B) can be bonded to the ends of the polyoxyethylene polymer or along the polymer chain between its ends, or multiple reactive silicon groups can be bonded to two of its ends and along the polymer chain between its ends. In particular, when the reactive silicon groups are only bonded to the ends, the network of polymer components contained in the composition is effectively constructed. Therefore, this is preferred because it is easy to obtain a rubbery cured product with high strength and elongation.

[0087] Various methods can be used to determine the introgression rate of reactive silicon groups in components (A) and (B). This ratio can be calculated based on the integral value of the ends of the introduced reactive silicon groups according to their 1H-NMR spectra. The introgression rate of reactive silicon groups is a percentage value obtained by dividing the number of reactive silicon groups present in the molecule by the number of ends of the molecule. Specifically, in the case of a linear polymer having an average of two reactive silicon groups in its single polymer chain (i.e., a polymer with two ends), an introgression rate of 100% is calculated. Therefore, for polymers with many reactive silicon groups present in portions other than the ends of the polymer chain, the calculated introgression rate may exceed 100%. In this invention, linear polymers having reactive silicon groups only at both ends are preferred. Polymers with an introgression rate of less than 85% are typically used. Linear polyoxyethylene polymers having reactive silicon groups only at both ends can be prepared as follows:

[0088] (a) Converting the hydroxyl groups present only at the ends of linear polyoxyethylene polymers into -OM groups (where M is Na or K). The resulting polymer is then reacted with the polymer derived from the formula CH2═C(R 4 )—CH2—Z (where R 4 As defined above, and where Z represents a halogen atom, an organohalogen compound is reacted to obtain a polyoxyethylene polymer having unsaturated groups only at its ends. Addition of the formula H—Si(R) 1 3-a )X a (where R) 1 (X and a are the same as defined above) represent hydrosilane compounds, which are reacted with polyoxyethylene polymers having one or more unsaturated groups only at their ends to obtain linear polyoxyethylene polymers having reactive silicon groups only at their ends.

[0089] (b) Straight-chain polyoxyethylene polymers having hydroxyl groups only at their ends and those having isocyanate groups and derived from the formula —Si(R 1 3-a )X a (where R) 1 The compounds represented by groups (X and a as defined above) are reacted to obtain linear polyoxyethylene polymers with reactive silicon groups only at their ends.

[0090] The number of reactive silicon groups in a single polymer chain of component (A) is preferably one or more on average, and more preferably 1.1 to 5.

[0091] The number of reactive silicon groups in a single polymer chain of component (B) is preferably 0.5 or more on average, and more preferably 0.8 to 3.

[0092] Specific examples of polyoxyethylene polymers having a reactive silicon group (A) are proposed in Japanese Patent Application Publication No. 45-36319, Japanese Patent Application Publication No. 46-12154, Japanese Unexamined Patent Application No. 50-156599, Japanese Unexamined Patent Application No. 54-6096, Japanese Unexamined Patent Application No. 55-13767, Japanese Unexamined Patent Application No. 55-13468, Japanese Unexamined Patent Application No. 57-164123, Japanese Patent Application Publication No. 3-2450, and U.S. Patent Nos. 3,632,557, 4,345,053, 4,366,307, and 4,960,844. Other examples are the polyoxyethylene polymers proposed in Japanese Patent Application Publication Nos. 61-197631, 61-215622, 61-215623, and 61-218632. The polyoxyethylene polymer is a polymer with a number-average molecular weight of 6000 or greater, a molecular weight distribution (Mw / Mn) of 1.6 or less, and reactive silicon groups, exhibiting high molecular weight and a narrow molecular weight distribution. However, component (A) is not particularly limited thereto.

[0093] The aforementioned polyoxyethylene polymers, each possessing reactive silicon groups, can be used individually or in combination of two or more of them.

[0094] The polyolefin polymer used in component (C) of this invention is not particularly limited and may be known in the art. Specific examples include polyolefin homopolymers such as ethylene, propylene, and butene, and copolymers thereof; ethylene-propylene-diene rubber (EPDM) and modified products thereof; chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene, copolymers thereof, and chlorinated polyolefins modified with acrylic acid moieties, maleic acid, and / or maleic anhydride; copolymers made from olefin and carboxylic acid monomers, such as ethylene-acrylic acid copolymers and isobutylene-maleic anhydride copolymers. The polyolefin polymer may be dispersed in a solvent or plasticizer. Specific examples of polyolefin polymers dispersed in a solvent or plasticizer include, but are not limited to, those shown below. 8203 8232, 8214 and its combinations.

[0095] The wet-curable adhesive compositions according to the invention comprise 1 to 100% by weight, preferably 10 to 70% by weight, of component (A) based on the total weight of the adhesive composition; 1 to 100% by weight, preferably 1 to 50% by weight, of component (B) based on the total weight of the adhesive composition; and 0.1 to 20% by weight, preferably 0.5 to 10% by weight, of component (C) based on the total weight of the adhesive composition. Surprisingly, these compositions achieve generally good adhesion to various substrates, including EPDM, PVC, and TPO, even without the use of a primer. These compositions can be formulated to be free of or contain only small amounts of volatile organic compounds (VOCs), posing no significant environmental burden, health risks, or fire hazards. The components used in the adhesive compositions are free-flowing liquids at room temperature, thus allowing for easy processing during adhesive manufacturing.

[0096] In some embodiments, the moisture-curable adhesive composition includes component (A) comprising an organic polymer containing reactive silicon groups. The organic polymer of component (A) is commercially available and / or can be prepared according to techniques known in the art. Examples of such polymers containing reactive silicon groups include, but are not limited to, silane-terminated polyethers and silane-terminated polyurethanes. More specific examples of commercially available polymers containing reactive silicon groups for component (A) include, but are not limited to, KANEKAMS. S327, KANEKA MS S227, KANEKA SAX220, and combinations thereof.

[0097] In some embodiments, the wettable adhesive composition comprises component (B), which is an organic polymer containing reactive silicone groups having a viscosity of less than 10,000 cP at 23°C and, in some embodiments, less than 5,000 cP at 23°C. Examples of commercially available low-viscosity polymers containing reactive silicone groups include, but are not limited to, KANEKA. SAT145, KANEKA SAT115, and combinations thereof.

[0098] The wettable curable adhesive composition of the present invention may optionally contain a variety of other additives, such as fillers, adhesion promoters, dehydrating agents, plasticizers, anti-sagging agents (thixotropic agents), stabilizers and curing catalysts.

[0099] In some embodiments, the moisture-curable adhesive composition may contain a variety of fillers. Examples of fillers include reinforcing fillers such as fumed silica, precipitated silica, crystalline silica, and carbon black; fillers such as heavy calcium carbonate, colloidal calcium carbonate, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium dioxide, and bentonite; and fiber fillers such as glass fibers and filaments.

[0100] In some embodiments, the wet-curable adhesive composition may contain a dehydrating agent to improve storage stability. The dehydrating agent may be, but is not limited to, alkoxysilane compounds, such as n-propyltrimethoxysilane, octyltrimethoxysilane, or vinyltrimethoxysilane.

[0101] In some embodiments, the wet-curable adhesive composition includes an adhesion promoter. The adhesion promoter may be selected from silane coupling agents, reaction products of silane coupling agents, or compounds other than silane coupling agents. Specific examples of silane coupling agents include, but are not limited to, isocyanate-containing silanes; amino-containing silanes; mercapto-containing silanes; epoxy-containing silanes; ethylene-unsaturated silanes; and halogen-containing silanes. Other silane coupling agents include derivatives obtained by modifying the above compounds, such as amino-modified silyl polymers, unsaturated aminosilane complexes, phenylamino long-chain alkyl silanes, aminosilylated silicones, and silylated polyesters.

[0102] In some embodiments, the wettable curable adhesive composition includes a curing / condensation catalyst. The condensation catalyst is added to the curable composition of the present invention to promote the hydrolysis and condensation of reactive silyl groups in the organic polymer containing reactive silicon groups to induce crosslinking. Examples of curing catalysts include, but are not limited to, titanium compounds such as tetrabutyl titanate, tetrapropyl titanate, and tetraacetylacetonate; tetravalent tin compounds such as dibutyltin dilaurate, dibutyltin maleate, dibutyltin phthalate, dibutyltin dioctanoate, dibutyltin diethylhexanoate, dimethyl dibutyltin maleate, diethyl dibutyltin maleate, dibutyltin dibutyl maleate, dioctyl dibutyltin maleate, dioctyl dibutyltin maleate, di-tetrazyl dibutyltin maleate, dibenzyl dibutyltin maleate, dibutyltin diacetate, diethyl dioctyltin maleate, dioctyl dioctyltin maleate, dibutyldimethoxytin, dinonylphenol dibutyltin, dibutylenyltin oxide, dibutyltin diacetylacetonate, and diethyl diacetylacetonate. The catalysts include, as well as the reaction products of dibutyltin oxide and phthalates; divalent tin compounds such as tin octoate, tin naphthenate, and tin stearate; organoaluminum compounds such as aluminum triacetylacetonate, aluminum triethylacetoacetate, and aluminum diisopropoxyethylacetoacetate; zirconium compounds such as zirconium tetraacetylacetonate; amine compounds such as aliphatic primary amines, aliphatic secondary amines, aliphatic tertiary amines, and aliphatic unsaturated amines; nitrogen-containing heterocyclic compounds such as pyridine, imidazole, and 1,8-diazabicyclo(5,4,0)undecene-7 (DBU); guanidines such as guanidine, phenylguanidine, and diphenylguanidine; biguanides such as butyl biguanide, 1-o-tolyl biguanide, and 1-phenyl biguanide; and other known silanol condensation catalysts, such as carboxylic acid metal salts, acidic catalysts, and basic catalysts. These catalysts can be used alone or in combination of two or more.

[0103] In some embodiments, the wet-curable adhesive composition may include an antioxidant. The antioxidant is preferably a hindered phenolic antioxidant. Examples of hindered phenolic antioxidants include, but are not limited to, those available from BASF. 245. 1010 and 1076 and its combinations.

[0104] In some embodiments, the wet-curable adhesive composition may include a light stabilizer. The light stabilizer can prevent photo-oxidative degradation of the cured product. Examples of light stabilizers include, but are not limited to, benzotriazole compounds, hindered amine compounds, and benzoate compounds.

[0105] In some embodiments, the adhesive composition may include a UV absorber. UV absorbers can improve the surface weather resistance of the cured product. Examples of UV absorbers include, but are not limited to, benzophenone compounds, benzotriazole compounds, salicylate compounds, substituted toluene compounds, and metal chelate compounds.

[0106] In some embodiments, the wet-curing adhesive composition may include a thixotropic agent. Specific examples of thixotropic agents include, but are not limited to, hydrogenated castor oil, organic amide waxes, organobentonite, and calcium stearate. These thixotropic agents may be used alone or in combination of two or more.

[0107] In some embodiments, the moisture-curable adhesive composition may include a plasticizer to control viscosity. Specific examples of plasticizers include, but are not limited to, phthalate compounds such as dibutyl phthalate, diisononyl phthalate, di(2-ethylhexyl) phthalate, and diisodecyl phthalate; non-phthalate compounds such as diisononyl 1,2-cyclohexanedicarboxylate; aliphatic polycarboxylate compounds; unsaturated fatty acid ester compounds, alkyl sulfonates, hydrocarbon oils, and polymer plasticizers such as polyether polyols. These plasticizers may be used alone or in combination of two or more.

[0108] Various other additives may optionally be incorporated into the wet-curing adhesive compositions of the present invention to control the properties of the curable composition or cured product. Examples of such additives include flame retardants, curing modifiers, lubricants, pigments, and antifungal agents. These additives may be used alone or in combination of two or more.

[0109] The curable compositions of the present invention will be described based on the following examples; however, the present invention is not limited to these examples.

[0110] Synthesis of Polymer 1

[0111] 400 g of polypropylene glycol (molecular weight 8000 g / mol) was loaded into a glass reactor equipped with a stirrer. The polypropylene glycol was heated to 60 °C. 5.86 g of isophorone diisocyanate was added dropwise to the reactor, followed by 0.16 g of tin catalyst (Fomrez SUL-4, dibutyltin dilaurate). The solution was stirred at 95 °C for 2 hours. Then, 9.13 g of 3-(trimethoxysilyl)propyl isocyanate was added to the reactor. The solution was stirred at 95 °C for another 5 hours to produce a polyoxypropylene polymer with trimethoxysilyl end groups.

[0112] The various blend components used in the examples and comparative examples in this article are listed below:

[0113] Component (A): Kaneka MS S327 and S227 are polyoxypropylene polymers containing methyl dimethoxysilyl groups, which are available from Kaneka Corp., and polymer 1.

[0114] Component (B): Kaneka Polymer SAT145 is a polyoxypropylene polymer containing methyl dimethoxysilyl groups, available from Kaneka Corp.

[0115] Component (C): 8203 is a xylene solution of chlorinated polypropylene resin, and 8232 is a solvent-free chlorinated polyolefin adhesive accelerator, both of which are available from Advanced Polymer, Inc.

[0116] Other additives include SYLVATAC RE25, a rosin ester tackifier available from Kraton Corporation; G2T is a surface-treated calcium carbonate available from Huber Engineered Materials in Atlanta, Georgia, USA. G8 is calcium carbonate, available from Huber Engineered Materials; 245, a sterically hindered phenolic antioxidant, is available from BASF; VTMO, a vinyltrimethoxysilane dehydrating agent, is available from Evonik Industries; DAMO-T, an N-(2-aminoethyl)-3-aminopropyltrimethoxysilane adhesive accelerator, is available from Evonik Industries; APS-P35, a silane / siloxane alkoxy oligomer adhesive accelerator, is available from Advanced Polymer, Inc.; Dyhard OTB, a 1-(o-tolyl)biguanide, is available from AlzChem Group; and Neostanan U220H, a dibutyltin diacetylacetonate, is available from Nitto Kasei Co., Ltd.

[0117] Comparative Examples 1 to 4 and Invention Examples 1 to 6

[0118] All components were weighed according to the formulations shown in Table 1, and then mixed and kneaded in a mixer under substantially anhydrous dehydration conditions. The mixture was then placed into a moisture-proof container (polyethylene cylinder). The curable compositions of Examples 1 to 6 and Comparative Examples 1 to 4 were prepared in this manner. The properties of the obtained curable compositions were measured as follows:

[0119] Viscosity: RV type Brookfield viscometer was used to measure the viscosity of each composition (spindle: No. 7, speeds of 2 and 10 rpm, temperature: 23°C).

[0120] Skin formation time: After each composition is applied to the substrate, the surface of the composition is smoothed. The point at which the surface is smoothed is defined as the start time. The time required for the mixture to no longer adhere to the scraper is determined by contacting the surface of the composition with a scraper and under conditions of 23°C and 50% relative humidity (“RH”).

[0121] Peel Strength: Adhesive strength was determined by a T-peel test. 1.0 inch × 6.0 inch specimens were cut from the EPDM monolayer top film. Each composition was applied to the EPDM specimen to form a uniform layer, and then another EPDM specimen was pressed on top of the adhesive layer. Three test specimens were prepared for each formulation. The specimens were cured for 28 days at 23°C and 50% RH. After 28 days of curing, the adhesive strength was measured using a Shimadzu Model AGS-20KNXD tensile testing machine at a peel rate of 2 inches / minute according to ASTM D 1876, and the average peel strength was recorded. The adhesive strength on PVC or TPO top film substrates was measured using the same method.

[0122] Preparation of T-type peel test specimens when using a primer: In some embodiments targeting TPO substrates 8203 is used as a primer: by using xylene... Prepare a primer solution by diluting 8203 to a 5% solids content. Apply the 5% solids solution to a TPO substrate and dry in a fume hood for at least 30 minutes. Then apply each adhesive composition on top of the primer to form a uniform layer, and then press another primer-coated TPO sample onto top of the adhesive layer. Allow the resulting material to cure for 28 days at 23°C and 50% RH. After 28 days of curing, measure the bond strength using a tensile testing machine at a peel rate of 2 inches / minute according to ASTM D 1876, and record the average peel strength.

[0123] As illustrated in the following examples, adhesive compositions containing tackifiers result in limitations during the manufacturing process. Tackifiers are known to those skilled in the art to be very viscous and sticky materials at room temperature. Before being incorporated into the adhesive formulation during the mixing process, the tackifier must be heated and melted. This can result in longer processing times. Although the resulting adhesive product may provide sufficient adhesion on certain substrates, the methods for producing adhesives containing tackifiers as components are not ideal. See, for example, Comparative Example 1, which includes a tackifier.

[0124] Conversely, the adhesive compositions of the present invention comprise polymers containing reactive silicone groups having low viscosity (i.e., a viscosity below about 10,000 cP at 23°C, or more preferably below 5,000 cP at 23°C). These polymers are readily incorporated into the adhesive formulation during the mixing process. Furthermore, due to the introduction of low-viscosity polymers into the formulation, the resulting adhesive compositions also have lower viscosity, and the resulting products are easy to apply during the application process. See, for example, Comparative Examples 1 and 2 and Example 1.

[0125] The inclusion of different adhesion promoters in adhesive compositions significantly affects adhesive strength. Here, T-peel strength was measured to examine adhesive performance. A T-peel strength below 4 psi ("pli") was considered poor. A T-peel strength between 4 and 5 psi was considered adequate. A T-peel strength between 5 and 6 psi was considered good, and a T-peel strength above 6 psi was considered excellent. For example, adhesive compositions containing only amino-silyl adhesion promoters were found to exhibit limited adhesion on all tested substrates with a T-peel strength below 4 psi (see, for example, Comparative Example 3). In contrast, adhesive compositions containing additional oligomeric silyl adhesion promoters (such as APS-P35) in the adhesion promoter component provided good adhesion on EPDM and PVC substrates with a T-peel strength above 5 psi without the use of a primer, but still required a primer on TPO to provide adequate adhesion (see, for example, Comparative Example 4). Surprisingly, even without a primer, adhesive compositions containing modified polyolefin adhesion promoters showed good adhesion. 8203 or The adhesive composition of 8232 also provides good adhesion to EPDM, PVC and TPO (Examples 1-5).

[0126] By selecting suitable polymers with highly flexible reactive silicon groups, the cured material exhibits high residual tack, which also helps to improve adhesion performance.

[0127] In addition to EPDM, PVC, and TPO, the adhesive formulations of the present invention (see, for example, Examples 1 and 4) also exhibit good adhesion to other difficult-to-adhere plastic substrates, such as polypropylene and resin-based coatings, such as Kynar's polyvinylidene fluoride coating.

[0128] Table 1. Comparative adhesive formulations

[0129]

[0130] Table 2. Adhesive Formulations of Embodiments of the Invention

[0131]

[0132] As shown in Tables 3 and 4, Examples 1 through 6 produced generally good adhesion on a range of anti-adhesive substrates. The substrates used in the Examples and Comparative Examples were all smooth-backed substrates. This is significantly superior to Comparative Examples 1 through 4.

[0133] Table 3. Typical adhesive properties of the comparative examples

[0134]

[0135] Table 4. Typical adhesive properties of the embodiments of the invention

[0136]

[0137] In summary, the curable composition disclosed herein comprises: component (A), which has an organic polymer containing a reactive silicon group represented by the following general formula (1): -Si(R 1 3-a )X a (1), where R 1 Represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, wherein X represents a hydrolyzable group, wherein when there are two or more X groups, each X may be the same or different, and a is an integer from 1 to 3. When a is 1, each R group... 1 They can be the same or different, and when a is 2 or 3, each X can be the same or different; component (B), which has an organic polymer containing reactive silicon groups, wherein the organic polymer has a viscosity of less than 10,000 cP at 23°C, and wherein the reactive silicon groups are represented by the following general formula (2): -Si(R 2 3-b )X b (2), where R 2 Represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, wherein X represents a hydroxyl group or a hydrolyzable group, wherein when there are two or more X groups, each X may be the same or different, and b is an integer from 1 to 3. When b is 1, each R group represents a hydroxyl group or a hydrolyzable group. 2 They can be the same or different, and when b is 2 or 3, each X can be the same or different; and have components (C) of polyolefin polymers; and / or

[0138] The organic polymer of component (B) has a viscosity of less than 5,000 cP at 23°C; and / or

[0139] The organic polymer of component (A) has a viscosity greater than 20,000 cP at 23°C; and / or

[0140] The organic polymer of component (A) comprises a polyoxypropylene backbone; and / or

[0141] The organic polymer of component (B) comprises a polyoxypropylene backbone; and / or

[0142] The organic polymer of component (A) comprises a group represented by the following general formula (3): –NR3C(=O)–(3), wherein R3 represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms; and / or

[0143] The organic polymer of component (B) comprises a group represented by the following general formula (4): –NR4C(=O)–(4), wherein R4 represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms; and / or

[0144] Component (C) comprises a chlorinated polyolefin polymer; and / or

[0145] Component (C) comprises a polymer modified with acrylic acid, maleic acid and / or maleic anhydride; and / or

[0146] Component (C) is a solvent or plasticizer used to disperse polyolefin polymers; and / or

[0147] The curable compositions of the present invention contain additives; and / or

[0148] The additives are selected from fillers, adhesion promoters, dehydrating agents, plasticizers, anti-sagging agents, stabilizers, curing catalysts, and combinations thereof.

[0149] This article also describes a method for applying the above-described curable composition, comprising applying the curable composition to a substrate; and / or

[0150] The substrate is selected from polyvinyl chloride (PVC), ethylene propylene diene rubber (EPDM), thermoplastic polyolefin (TPO); and / or

[0151] The substrate is a smooth-backed substrate; and / or

[0152] The method further includes applying a primer to the substrate before applying the curable composition.

[0153] This document also describes a composition comprising a substrate and the above-described curable composition; and / or

[0154] The substrate is selected from polyvinyl chloride (PVC), ethylene propylene diene rubber (EPDM), thermoplastic polyolefin (TPO); and / or

[0155] The substrate is a smooth back substrate.

[0156] Although the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. Therefore, it should be understood that various modifications can be made to the illustrative embodiments and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A curable composition comprising: A polymer composed of: Component (A) having an organic polymer containing a reactive silicon group represented by the following general formula (1): —Si(R 1 3-a )X a (1) Where R 1 represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, wherein X represents a hydrolyzable group, wherein when there are two or more Xs, each X is the same or different, a is an integer from 1 to 3, When a is 1, each R 1 can be the same or different, and When a is 2 or 3, each X may be the same or different; Component (B) having an organic polymer containing a reactive silicon group, wherein the organic polymer of component (B) has a viscosity of less than 10,000 cP at 23° C., wherein the reactive silicon group is represented by the following general formula (2): —Si(R 2 3-b )X b (2) Where R 2 represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, wherein X represents a hydroxyl group or a hydrolyzable group, wherein when there are two or more Xs, each X is the same or different, b is an integer from 1 to 3, When b is 1, each R 2 can be the same or different, and When b is 2 or 3, each X may be the same or different; and Component (C) having a polyolefin polymer, in, The component (C) is present in an amount of 0.5 to 10 wt %, based on the total weight of the curable composition.

2. The curable composition according to claim 1, wherein the organic polymer of component (B) has a viscosity of less than 5,000 cP at 23°C.

3. The curable composition according to claim 1, wherein the organic polymer of component (A) has a viscosity at 23°C of greater than 20,000 cP.

4. The curable composition of claim 1, wherein the organic polymer of component (A) comprises a polyoxypropylene backbone.

5. The curable composition of claim 1, wherein the organic polymer of component (B) comprises a polyoxypropylene backbone.

6. The curable composition according to claim 1, wherein the organic polymer of component (A) comprises a group represented by the following general formula (3): –NR 3 C(=O)– (3) Where R 3 represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms.

7. The curable composition according to claim 1, wherein the organic polymer of component (B) comprises a group represented by the following general formula (4): –NR 4 C(=O)– (4) Where R 4 represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms.

8. The curable composition of claim 1, wherein component (C) comprises a chlorinated polyolefin polymer.

9. The curable composition of claim 1, wherein component (C) comprises a polymer modified with acrylic moieties, maleic acid or maleic anhydride.

10. The curable composition according to claim 1, wherein component (C) comprises a solvent or a plasticizer to disperse the polyolefin polymer.

11. The curable composition according to claim 1, further comprising: additive.

12. The curable composition of claim 11, wherein the additive is selected from the group consisting of fillers, adhesion promoters, dehydrating agents, plasticizers, anti-sagging agents, stabilizers, curing catalysts, and combinations thereof.

13. A method of applying a curable composition comprising: The curable composition of claim 1 is applied to a substrate.

14. The method of claim 13, wherein the substrate is selected from the group consisting of polyvinyl chloride (PVC), ethylene propylene diene rubber (EPDM), and thermoplastic polyolefin (TPO).

15. The method of claim 14, wherein the substrate is a smooth back substrate.

16. The method of claim 13, further comprising: A primer is applied to the substrate prior to application of the curable composition.

17. A composition comprising: substrate; and The curable composition according to claim 1.

18. The composition of claim 17, wherein the substrate is selected from the group consisting of polyvinyl chloride (PVC), ethylene propylene diene rubber (EPDM), and thermoplastic polyolefin (TPO).

19. The composition of claim 18, wherein the substrate is a smooth back substrate.

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