Reactive hot melt adhesive composition and uses thereof

Abstract

The present invention relates to a reactive hot melt adhesive composition and its use. In particular, the present invention provides an adhesive composition comprising at least one reactive polyurethane prepolymer obtained by reacting a reactant mixture comprising (A), (a) at least one polyol, and (b) at least one polyisocyanate having at least two isocyanate groups per molecule; (B) at least one vinyl acetate homopolymer having a weight average molecular weight (Mw) of 15,000 to less than 100,000 g / mol and present in an amount of less than 70 wt. % based on the total weight of the adhesive composition.

Description

[Technical field]

[0001] Technical Field The present invention relates to a reactive hot melt adhesive composition and its use. In particular, the present invention relates to a reactive hot melt adhesive composition comprising a vinyl acetate homopolymer, which can meet the needs of various applications. [Background technology]

[0002] background Moisture-curing polyurethane hot melt adhesives have been used for many years and are widespread, as described, for example, in HF Hueber and H. Mueller, “Shaping Reactive Hotmelts Using LMW Copolyesters”, (Adhesives Age, November 1987, pp. 32-35). In industrial applications, moisture-curing polyurethane hot melt adhesives are solid at room temperature, but when heated to a moderate temperature, they melt into a viscous liquid and are applied to a substrate for bonding. The molten adhesive composition is then cooled and solidifies, forming an initial bond with the substrate. It further reacts with moisture to form a crosslinked structure, achieving high final strength. Such adhesives may consist of a polyol component and an isocyanate component with two or more functional groups. These adhesives are preferred over other adhesives in a variety of applications due to their excellent adhesive strength, flexibility, and resistance to impact and fatigue.

[0003] Currently, moisture-curable polyurethane hot melt adhesives are commonly used in the industry to be mixed with resins such as acrylic, ethylene vinyl acetate (EVA), and thermoplastic polyurethane (TPU) resins to improve the inherent cohesive and initial bond strength of the adhesive to various materials. Polyvinyl acetate (PVAc) has long been used in various applications in various technical fields due to its excellent adhesive strength with various substrates and low odor. For example, polyvinyl acetate is a film-forming component of many water-based (latex) adhesives and paints. However, polyvinyl acetate is rarely mixed with polyurethane hot melt adhesives due to compatibility issues. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] HF Hueber and H. Mueller “Shaping Reactive Hotmelts Using LMW Copolyesters”, (Adhesives Age, November 1987, pp. 32-35) Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, there is a need in the art for a moisture-curable polyurethane hot melt adhesive that can incorporate polyvinyl acetate as a component to provide an adhesive composition that, upon cure, has a wide range of open times and good initial bond strength to different substrates. [Means for solving the problem]

[0006] Summary of the Invention Disclosed herein is a method for producing a medicament for the treatment of a pulmonary arthritis, comprising: At least one reactive polyurethane prepolymer obtained by reacting a reactant mixture comprising (A), (a) at least one polyol, and (b) at least one polyisocyanate having at least two isocyanate groups per molecule; and (B) at least one vinyl acetate homopolymer having a weight average molecular weight (Mw) of 15,000 to less than 100,000 g / mol and present in an amount of less than 70 wt. %, based on the total weight of the adhesive composition; The present invention relates to a moisture-curable polyurethane hot melt adhesive composition comprising:

[0007] Also disclosed herein are cured products of the moisture-curable hot melt adhesive compositions according to the present invention.

[0008] Also disclosed herein is a laminate comprising a first substrate, a second substrate, and an adhesive layer sandwiched therebetween, wherein the first and second substrates are independently selected from glass, resin, textile, wood, and metal, and the adhesive layer is formed by curing an adhesive composition according to the present invention.

[0009] Also disclosed herein is the use of the moisture-curable hot melt adhesive composition according to the present invention in the manufacture of consumer goods, automotive parts, electronic devices, and home appliances.

[0010] Other features and aspects of the subject matter are described in further detail below. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Detailed Description Those skilled in the art will appreciate that this description is merely of exemplary embodiments and is not intended to limit the broader aspects of the invention.

[0012] Unless otherwise specified, in the context of the present invention, terms used shall be construed in accordance with the following definitions.

[0013] Unless otherwise specified, as used herein, the terms "a," "an," and "the" include both the singular and the plural.

[0014] As used herein, the terms "comprising" and "comprises" are synonymous with "including," "includes," or "containing," and "contains," and are inclusive or open-ended and do not exclude additional, unlisted members, elements, or process steps.

[0015] The terms "at least one" or "one or more" used herein to define components refer to the type of component and not to the absolute numerical value of the molecule. For example, "one or more polyols" refers to one type of polyol or a mixture of multiple different polyols.

[0016] The term "amorphous" as used herein means the absence of a melting transition as measured using differential scanning calorimetry (DSC).

[0017] As used herein, the term "crystalline" means having a melting transition as measured using differential scanning calorimetry (DSC).

[0018] As used herein, the term "room temperature" refers to a temperature of about 20°C to about 25°C, preferably about 25°C.

[0019] Unless otherwise specified, the recitation of numerical endpoints includes not only the recited endpoints but also all values ​​and fractions subsumed within each range.

[0020] Molecular weight refers to weight average molecular weight (Mw) unless otherwise specified. All molecular weight data refers to values ​​obtained by gel permeation chromatography (GPC) unless otherwise specified, such as DIN 55672.

[0021] In this context, the glass transition temperature (Tg) or melting point of a particular polymer is determined using DSC in accordance with DIN 53 765.

[0022] Unless otherwise defined, all terms, including technical and scientific terms, used herein have the meaning commonly understood by one of ordinary skill in the art to which this invention belongs.

[0023] According to a first aspect, the present invention generally comprises: At least one reactive polyurethane prepolymer obtained by reacting a reactant mixture comprising (A), (a) at least one polyol, and (b) at least one polyisocyanate having at least two isocyanate groups per molecule; and (B) at least one vinyl acetate homopolymer having a weight average molecular weight (Mw) of 15,000 to less than 100,000 g / mol and present in an amount of less than 70 wt. %, based on the total weight of the adhesive composition; The present invention relates to a moisture-curable polyurethane hot melt adhesive composition comprising:

[0024] (A) Reactive polyurethane prepolymer According to the present invention, the moisture-curable polyurethane hot melt adhesive composition comprises at least one reactive polyurethane prepolymer obtained by reacting a reactant mixture comprising (a) at least one polyol, and (b) at least one polyisocyanate having at least two isocyanate groups per molecule.

[0025] In some embodiments, the reactive polyurethane prepolymer has a number average molecular weight (Mn) of 5,000 to 30,000 g / mole, preferably 8,000 to 20,000 g / mole.

[0026] In some embodiments, component (A) is present in an amount of more than 30% but less than 100% by weight, preferably from 40% to 99% by weight, more preferably from 45% to 90% by weight, and even more preferably from 50% to 65% by weight, based on the total weight of the adhesive composition.

[0027] (a) Polyol In some embodiments, reactant (a) can be selected from polyester polyols, polyether polyols, and combinations thereof.

[0028] In a preferred embodiment, a polyester polyol can be used as reactant (a), which can be selected from solid polyester polyols, liquid polyester polyols, and combinations thereof, preferably selected from crystalline polyester polyols, amorphous polyester polyols, liquid polyester polyols, and combinations thereof.

[0029] When present, crystalline polyester polyols can be used in the present invention, which can provide good adhesive strength to the adhesive composition.

[0030] Examples of such crystalline polyester polyols can be obtained by ring-opening polymerization of lactones such as ε-caprolactone and / or derived from diols and diacids. Examples of diols useful for making preferred polyester polyols include ethylene glycol, diethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, and combinations thereof. Examples of diacids useful for making preferred polyester polyols include succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and 1,12-dodecanedioic acid, dimer acid, and combinations thereof. The range of useful diacids includes various diacid derivatives such as carboxylate esters (especially methyl esters and ethyl esters), acid halides (such as acid chlorides), acid anhydrides, and combinations thereof.

[0031] Specific examples of suitable crystalline polyester polyols include poly(hexanediol adipate) polyol, poly(butanediol adipate) polyol, polyepsilon caprolactone polyol, poly(hexanediol decanedioic acid) polyol, poly(hexanediol adipate terephthalate) polyol, and combinations thereof.

[0032] Suitable commercially available crystalline polyester polyols are sold under the trade name DYNACOLL 7300 series by Evonik Industries AG, including DYNACOLL 7360, 7361, 7362, 7363, 7380, 7381, 7390, etc., and under the trade name CAPA series by Perstorp Polyols Inc., including CAPA 2201, 2205, 2209, 2302, 2304, 2402, etc. Also included are caprolactone polyols and AR U 2720 available from Yong Shun Chemicals Co., Ltd.

[0033] When present, amorphous polyester polyols may also be used in preparing the reactive polyurethane prepolymers of the present invention.

[0034] Amorphous polyester polyols include the reaction product of a polyacid component (e.g., a polyacid, a polyanhydride, a polyacid ester, a polyacid halide) with a stoichiometric excess of a polyol. At least one of the polyacid component and the polyol contains an aromatic group. Suitable polyacids include, for example, diacids (e.g., dicarboxylic acids), triacids (e.g., tricarboxylic acids), and higher acids, including aromatic dicarboxylic acids, their anhydrides and esters (e.g., terephthalic acid, isophthalic acid, dimethyl terephthalic acid, diethyl terephthalic acid, phthalic acid, phthalic anhydride, methylhexahydrophthalic acid, methylhexahydrophthalic anhydride, methyltetrahydrophthalic acid, methyltetrahydrophthalic anhydride, hexahydrophthalic acid, hexahydrophthalic anhydride, tetrahydrophthalic acid ... ), aliphatic dicarboxylic acids and their anhydrides (e.g., maleic acid, maleic anhydride, succinic acid, succinic anhydride, glutaric acid, glutaric anhydride, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, chlorendic acid, 1,2,4-butanetricarboxylic acid, decanedicarboxylic acid, octadecanedicarboxylic acid, dimerized acid, dimerized fatty acid, trimerized fatty acid, fumaric acid), and alicyclic dicarboxylic acids (e.g., 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid), and mixtures thereof.Examples of suitable polyols include aliphatic polyols, such as ethylene glycol, propanediols (e.g., 1,2-propanediol and 1,3-propanediol), butanediols (e.g., 1,3-butanediol, 1,4-butanediol, 1,2-butanediol), 1,3-butenediol, 1,4-butenediol, 1,4-butynediol, pentanediols (e.g., 1,5-pentanediol), pentenediol, pentynediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, neopentyl glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, Examples of suitable glycerols include glycerol, polyethylene glycol, propylene glycol, polypropylene glycol (e.g., dipropylene glycol, tripropylene glycol), 1,4-cyclohexanedimethanol, 1,4-cyclohexanediol, dimer diol, bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F, glycerol, tetramethylene glycol, polytetramethylene glycol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, trimethylolpropane, pentaerythritol, sorbitol, glucose, and combinations thereof.

[0035] Specific examples of useful amorphous polyester polyols, when present, include poly(hexanediol phthalate) polyol, poly(neopentyl glycol adipate) polyol, poly(neopentyl glycol phthalate) polyol, poly(neopentyl glycol hexanediol phthalate) polyol, poly(diethylene glycol phthalate) polyol, poly(ethylene glycol adipate terephthalate) polyol, polyethylene terephthalate polyol, ethylene glycol, hexanediol, neopentyl glycol, random copolymer diols of adipic acid and terephthalic acid, and combinations thereof.

[0036] Useful amorphous polyester polyols are commercially available under various trade names, such as, for example, DYNACOLL 7110, 7130, 7140, 7150 from Evonik Industries AG, and FLP PA-1000N from Xuchuan Chemical (Suzhow) Co., Ltd.

[0037] In some embodiments, the polyester polyol used in the present invention can be liquid at room temperature, which imparts wettability to the adhesive composition and impact resistance to the cured product. Therefore, the liquid polyester polyol preferably has a glass transition temperature (Tg) of 0° C. or less. If the Tg of the liquid polyester polyol is too high, it is difficult to become liquid.

[0038] Examples of suitable liquid polyester polyols include those obtained by ring-opening polymerization of lactones such as ε-caprolactone, and / or derived from diols and diacids. Examples of diols useful for making preferred polyester polyols include ethylene glycol, diethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, and combinations thereof. Examples of diacids useful for making preferred polyester polyols include succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and 1,12-dodecanedioic acid, dimer acid, and combinations thereof. The range of useful diacids includes various diacid derivatives such as carboxylate esters (especially methyl and ethyl esters), acid halides (such as acid chlorides), acid anhydrides, and combinations thereof.

[0039] Specific examples of suitable liquid polyester polyols include poly(hexanediol adipate) polyol, poly(butanediol adipate) polyol, polyepsilon caprolactone polyol, poly(hexanediol decanedioic acid) polyol, poly(hexanediol adipate terephthalate) polyol, and mixtures thereof.

[0040] Suitable commercially available liquid polyester polyols are sold under the trade designation DYNACOLL 7200 series (DYNACOLL 7210, 7230, 7231, 7250, etc.) by Evonik Industries AG and Stepan PDP 70 by Stepan Corporation.

[0041] In some embodiments, reactant (a) can be a polyether polyol.

[0042] The polyether polyols used in the present invention are well known to those skilled in the art.These polyether polyols are obtained by copolymerizing at least one compound, such as ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, and at least one compound having at least two active hydrogen atoms in average in one molecule, such as the above polyhydric alcohols, including ethylene glycol, propylene glycol, dipropylene glycol, glycerol, and combinations thereof.Other suitable polyhydric compounds include sucrose, ethylenediamine, propylenediamine, triethanolamine, 1,2-propanedithiol, and combinations thereof.

[0043] Preferred polyether polyols can be selected from polytetramethylene ether glycol, poly(oxypropylene) glycol, polyethylene oxide, polybutylene oxide, and ethylene oxide end-capped versions of any of the foregoing, and combinations thereof. Most preferred polyether polyols are polytetramethylene ether glycol, poly(oxypropylene) glycol, ethylene oxide end-capped poly(oxypropylene) glycol, and combinations thereof.

[0044] In a preferred embodiment, the polyether polyol has a number average molecular weight (Mn) of 200 to 8,000 g / mol, preferably 400 to 4,000 g / mol, more preferably 400 to 2,000 g / mol.

[0045] Commercially available products may also be used in the present invention, examples of which include Voranol 2104, 2110, 2120, and 2140 from The Dow Chemical Company.

[0046] In some embodiments, reactant (a) is a combination of a polyester polyol and a polyether polyol. Preferably, to form the reactive polyurethane prepolymers of the present invention, reactant (a) does not include a polyether polyol.

[0047] Particularly preferably, reactant (a) may be present in an amount of from 20% to 85% by weight, more preferably from 40% to 80% by weight, based on the total weight of the adhesive composition.

[0048] (b) Polyisocyanate According to the present invention, the moisture-curable polyurethane hot melt adhesive composition comprises at least one reactive polyurethane prepolymer obtained by reacting a reactant mixture comprising (a) at least one polyol, and (b) at least one polyisocyanate having at least two isocyanate groups per molecule.

[0049] Polyisocyanates useful as reactant (b) include any suitable isocyanate having at least two isocyanate groups in one molecule, including, for example, aliphatic, cycloaliphatic, araliphatic, aryl alkyl, aromatic isocyanates, and combinations thereof.

[0050] Preferred reactants (b) are 4,4'-diphenylmethane diisocyanate (MDI), hydrogenated MDI (H12MDI), partially hydrogenated MDI (H6MDI), xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), 4,4'-diphenyldimethylmethane diisocyanate, dialkylene diphenylmethane diisocyanate, tetraalkylene diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, Isomers of toluylene diisocyanate (TDI), 1-methyl-2,4-diisocyanatocyclohexane, 1,6-diisocyanato-2,2,4-trimethylhexane, 1,6-diisocyanato-2,4,4-trimethylhexane, 1-isocyanatomethyl-3-isocyanato-1,5,5-trimethylcyclohexane (IPDI) , Tetramethoxybutane-1,4-diisocyanate, Naphthalene-1,5-diisocyanate (NDI), Butane-1,4-diisocyanate, Hexane-1,6-diisocyanate (HDI), Dicyclohexylmethane diisocyanate, 2,2,4-trimethylhexane-2,3,3-trimethylhexamethylene diisocyanate, Cyclohexane-1,4-diisocyanate, Ethylene diisocyanate, Methylene triphenyl The polyisocyanate may be selected from 4,4'-diphenylmethane diisocyanate (MIT), phthalic acid bisisocyanatoethyl ester, trimethylhexamethylene diisocyanate, 1,4-diisocyanatobutane, 1,12-diisocyanatododecane, dimer fatty acid diisocyanate, lysine ester diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,3-cyclohexane or 1,4-cyclohexane diisocyanate, and combinations thereof. The most preferred polyisocyanate is 4,4'-diphenylmethane diisocyanate (MDI) and its isomers, chain extended MDI, and combinations thereof.

[0051] Useful commercially available polyisocyanates for use as reactant (b) include DESMODUR 44C FUSED, Desmodur 0118 I, and Desmodur 44M from Covestro, Vannate MDI 100F from Wanhua Chemicals, and Supresec 1809 from HUNTSMAN.

[0052] Particularly preferably, reactant (b) may be present in an amount of 5% to 25% by weight, preferably 10% to 20% by weight, based on the total weight of the adhesive composition.

[0053] (B) Vinyl acetate homopolymer According to the present invention, the moisture-curable polyurethane hot melt adhesive composition comprises (B) at least one vinyl acetate homopolymer having a weight average molecular weight (Mw) of from 15,000 to less than 100,000 g / mol and present in an amount of less than 70 wt.%, based on the total weight of the adhesive composition.

[0054] In a preferred embodiment, component (B) used in the present invention may be a vinyl acetate homopolymer in the range of 30,000 to 60,000 g / mol, more preferably in the range of 45,000 to 55,000 g / mol.

[0055] Suitable vinyl acetate homopolymers for use as component (B) of the present invention can be conventionally prepared by emulsion polymerization techniques which, in addition to vinyl acetate monomer and water, typically include small amounts of wetting agents, protective colloids, polymerization initiators and molecular weight regulators.

[0056] Useful commercially available vinyl acetate homopolymers for use as component (B) include Vinnapas™ N 1.5 SP, Vinnapas™ N 17 SP, and Vinnapas™ N 30 SP, available from Wacker Chemicals (China) Co., Ltd.

[0057] Particularly preferably, component (B) can be present in an amount of greater than 0% and less than 70% by weight, preferably from 1% to 60% by weight, more preferably from 5% to 45% by weight, based on the total weight of the adhesive composition.

[0058] (C)Catalyst Optionally, the moisture-curable polyurethane hot melt adhesive composition may also contain a catalyst (C) for promoting the reaction between (a) the polyol and (b) the polyisocyanate having at least two isocyanate groups per molecule.

[0059] Suitable components (C) are, for example, strongly basic amides such as 2,3-dimethyl-3,4,5,6-tetrahydropyrimidine, tris-(dialkylaminoalkyl)-s-hexahydrotriazines, for example tris-(N,N-dimethylaminopropyl)-s-hexahydrotriazine, or conventional tertiary amines, for example triethylamine, tributylamine, dimethylbenzylamine, N-ethyl-, N-methyl-, N-cyclohexylmorpholine, dimethylcyclohexylamine, dimorpholinodiethyl ether, 2-(dimethylaminoethoxy)-ethanol, 1,4-diazabicyclo[2,2,2]octane, 1-azabicyclo[3,3,0]octane, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethylbutanediamine, N,N,N',N'-tetramethylhexane-1,6-diamine, pentamethyldiethylenetriamine, tetramethyl diaminoethyl ether, bis-(dimethylaminopropyl)-urea, N,N'-dimethylpiperazine, 1,2-dimethylimidazole, di-(4-N,N-dimethylaminocyclohexyl)-methane, and the like; and organometallic compounds such as titanates; iron compounds such as iron(III) acetylacetonate; tin compounds such as tin(II) salts of organic carboxylic acids, for example tin(II) diacetate, tin(II) salts of 2-ethylhexanoic acid (tin(II) octoate), tin(II) dilaurate; or dialkyltin(IV) salts of organic carboxylic acids, for example dibutyltin(IV) diacetate, dibutyltin(IV) dilaurate, dibutyltin(IV) maleate, or dioctyltin(IV) diacetate; and dibutyltin(IV) dimercaptides or mixtures of two or more of the above catalysts; and synergistic combinations of strongly basic amines and organometallic compounds.

[0060] Particularly preferably, the catalyst may be present in the adhesive composition in an amount of 0 to 1% by weight, preferably 0.01% to 0.5% by weight, based on the total weight of the adhesive composition.

[0061] (D) Additives Optionally, the moisture-curable polyurethane hot melt adhesive composition may contain at least one additive, such as a colorant, an antioxidant, a leveling agent, an anti-yellowing agent, or the like, which is commonly used in the art.

[0062] Examples of colorants include pigments that can be selected from metal oxide pigments, titanium dioxide (optionally surface treated), zirconium or cerium oxides, zinc oxide, iron oxides (black, yellow or red), chromium oxide, manganese, and combinations thereof.

[0063] Examples of antioxidants include BHT (butylated hydroxytoluene), octadecyl-3,5-bis(1,1-dimethyl)-4-hydroxybenzenepropanoate, phenols such as pyrogallol, phosphites such as triphenyl phosphite, tris(nonylphenyl)phosphite, or thioesters such as dilaurylthiodipropionate, and combinations thereof.

[0064] Particularly preferably, the additive may be present in an amount of 0 to 5% by weight, preferably 0.05% to 2% by weight, based on the total weight of the adhesive composition.

[0065] Adhesive Composition In a particularly preferred embodiment, the moisture-curable polyurethane hot melt adhesive composition comprises, based on the total weight of the adhesive composition: More than 30% by weight and less than 100% by weight, preferably 40% by weight to 99% by weight, more preferably 45% by weight to 90% by weight, and even more preferably 50% by weight to 65% by weight; (a) at least one polyol, and (b) at least one polyisocyanate having at least two isocyanate groups per molecule; (A) at least one reactive polyurethane prepolymer obtained by reacting a reactant mixture comprising: 0% to less than 70%, preferably 1% to 60%, more preferably 5% to 45% by weight of (B) at least one vinyl acetate homopolymer having a weight average molecular weight (Mw) of 15,000 to less than 100,000 g / mol; 0 to 1% by weight, preferably 0.01 to 0.5% by weight, of (C) a catalyst, and 0 to 5% by weight, preferably 0.05 to 2% by weight of (D) additive Includes.

[0066] Preparation method The moisture-curable polyurethane hot melt adhesive composition according to the present invention can be produced by the following steps to obtain the composition: (i) mixing reactant (a) and component (B) at a temperature of 125°C to 150°C, followed by evacuation; (ii) lowering the temperature to 100°C-120°C, adding reactant (b), and controlling the reaction temperature to 120°C-130°C; and (iii) Mixing under vacuum for 1-2 hours to make it uniform, then discharging.

[0067] The apparatus used for mixing, stirring, dispersing, etc. is not particularly limited. An automatic mortar equipped with a stirrer or heater, a Henschel mixer, a three-roll mill, a ball mill, a planetary mixer, a bead mill, etc. can be used. These apparatuses may also be used in appropriate combination. The method for producing the moisture-curable polyurethane hot melt adhesive composition is not particularly limited as long as the composition is a uniform mixture of the above components.

[0068] Cured Products and Laminates The moisture-curable polyurethane hot melt adhesive composition of the present invention can be cured at 15° C. to 35° C., preferably at room temperature, and at a relative humidity of 50% for 1 to 7 days.

[0069] As will be appreciated, the cure time and temperature profile of each moisture curable polyurethane hot melt adhesive composition will vary, and different compositions can be designed to provide a cure profile suitable for a particular industrial manufacturing process.

[0070] According to a second aspect of the present invention, there is provided a cured product of the moisture-curable polyurethane hot melt adhesive of the present invention.

[0071] According to a third aspect of the present invention, there is provided a laminate comprising a first substrate, a second substrate and an adhesive layer disposed therebetween, the first and second substrates being independently selected from glass, resin, textile, wood and metal, and the adhesive layer being formed by curing an adhesive composition of the present invention.

[0072] Specifically, the moisture-curable polyurethane reactive hot melt adhesive composition according to the present invention contains component (B) in an amount of less than 30 wt %, preferably less than 20 wt %, based on the total weight of the adhesive composition, and can be used for bonding textiles together in clothing, or between textiles and foams. On the other hand, the moisture-curable polyurethane reactive hot melt adhesive composition according to the present invention contains component (B) in an amount of 30 wt % to less than 70 wt %, preferably 45 wt % to less than 70 wt %, based on the total weight of the adhesive composition, and can be used for bonding wood substrates.

[0073] The first substrate and / or the second substrate may be composed of a single material and a single layer, or may be composed of multiple layers of the same or different materials. The layers may be continuous or discontinuous.

[0074] The substrate of the articles described herein can have a variety of properties, including rigidity (e.g., in the case of a rigid substrate, i.e., the substrate cannot be bent using two hands or would break if an attempt was made to bend it using two hands), flexibility (e.g., in the case of a flexible substrate, i.e., the substrate can be bent with less than the strength of two hands), porosity, electrical conductivity, lack of electrical conductivity, and combinations thereof.

[0075] The substrate of the article can take a variety of forms, such as, for example, fibers, threads, yarns, woven fabrics, nonwoven fabrics, films (e.g., polymeric films, metallized polymeric films, continuous films, discontinuous films, and combinations thereof), foils (e.g., metal foils), sheets (e.g., metal sheets, polymeric sheets, continuous sheets, discontinuous sheets, and combinations thereof), and combinations thereof.

[0076] In a preferred embodiment, at least one of the substrates can be selected from metals such as metal fired pastes, aluminum, tin, molybdenum, silver, conductive metal oxides such as indium tin oxide (ITO), fluorine doped tin oxide, aluminum doped zinc oxide, glass such as ink glass, bare glass, resins such as polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyamide, polyvinyl chloride, etc. Further suitable metals include copper, gold, palladium, platinum, aluminum, indium, silver plated copper, silver plated aluminum, tin, and tin plated copper. Preferably, both substrates are selected from any of the aforementioned materials.

[0077] The moisture-curable polyurethane hot melt adhesive composition of the present invention can be applied to a substrate using any suitable application method including, for example, automated fine line application, jet application, slot die coating, roll coating, gravure coating, transfer coating, pattern coating, screen printing, spray coating, filament coating, extrusion, air knife, trailing blade, brushing, dipping, doctor blade, offset gravure coating, rotogravure coating, and combinations thereof. The moisture-curable polyurethane hot melt adhesive composition can be applied as a continuous or discontinuous coating, in single or multiple layers, and combinations thereof.

[0078] use According to the present invention, the moisture curable polyurethane reactive hot melt adhesive composition is useful in the manufacture of consumer goods, automotive parts, electronic devices, and household appliances.

[0079] Suitable consumer goods include, but are not limited to, for example, textiles and apparel, wood products and furniture, paper and plastic packaging, and other components.

[0080] Suitable electronic devices include, but are not limited to, wearable electronic devices (e.g., watches and glasses), handheld electronic devices (e.g., phones (e.g., cell phones and smartphones), cameras, tablets, e-readers, monitors (e.g., monitors used by hospitals and healthcare professionals, athletes, and individuals), watches, calculators, mice, touchpads, joysticks), computers (e.g., desktop and laptop computers), computer monitors, televisions, media players, or other electronic components.

[0081] Such suitable household appliances include, but are not limited to, refrigerators, washers, dryers, ovens, microwaves, etc.), light bulbs (e.g., incandescent bulbs, light emitting diodes, fluorescent bulbs, etc.), and other items. EXAMPLES

[0082] Working Example The following examples are intended to aid those skilled in the art in better understanding and practicing the present invention. The scope of the present invention is not limited by the examples, but is defined by the appended claims. Unless otherwise specified, all parts and percentages are by weight.

[0083] raw materials AR U 2720 is a polyester polyol available from Yong Shun Chemicals Co., Ltd.

[0084] Desmodur TM 44M is 4,4'-MDI available from Covestro.

[0085] Vinnapas TM N 17 SP is a vinyl acetate homopolymer with a weight average molecular weight (Mw) of 45,000 g / mol, available from Wacker Chemicals (China) Co. Ltd.

[0086] Vinnapas TM N 1.5 SP is a vinyl acetate homopolymer with a weight average molecular weight (Mw) of 15,000 g / mol, available from Wacker Chemicals (China) Co. Ltd.

[0087] Vinnapas TM N 30 SP is a vinyl acetate homopolymer with a weight average molecular weight (Mw) of 55,000 g / mol, available from Wacker Chemicals (China) Co. Ltd.

[0088] Vinnapas TM N 100 SP is a vinyl acetate homopolymer with a weight average molecular weight (Mw) of 100,000 g / mol, available from Wacker Chemicals (China) Co. Ltd.

[0089] Hanwha 1540 is an ethylene-vinyl acetate copolymer available from Hanwha Chemicals.

[0090] Elvacite TM 2013 is an acrylic resin available from Mitsubishi Chemical Corporation.

[0091] Pearlbond TM 521 is a polycaprolactone copolyester polyurethane available from Lubrizol.

[0092] Sample preparation The samples were prepared according to the recipes listed in Tables 1, 2 and 3. The total weight of all components is 100 parts by weight. In the following tables, the compositions were prepared by the following procedure: (i) mixing reactant (a) with component (B) or other resins replacing component (B) at a temperature of 125°C to 150°C, followed by vacuuming; (ii) lowering the temperature to 100°C-120°C, adding reactant (b), and controlling the reaction temperature to 120°C-130°C; and (iii) Mix under vacuum for 1-2 hours and then drain.

[0093] The state of the resulting compositions was recorded as "homogeneous" or "phase separated" by visual observation. A "phase separated" composition means that the components in each composition have compatibility problems, which reduces workability and is therefore unacceptable.

[0094] Test Method: Viscosity of hot melt adhesive composition The viscosity in the present invention was measured using a Brookfield viscometer with a 27# spindle at a temperature range of 130° C. Viscosities of less than 10,000 cps are acceptable.

[0095] Initial adhesive strength after 2 minutes and 10 minutes Each sample prepared as above was applied between two layers of PET film (available from Lianrui Corporation, Dongguan) with a size of 1 m × 0.18 m at 105 °C using a roller heater (available from Weite Corporation, Taiwan) to a thickness of 50 μm to prepare a laminated sample.

[0096] The laminated samples were cured for 2 minutes at 23°C and 50% relative humidity. The 180° peel strength was recorded as the initial adhesive strength of the cured laminated samples. The laminated samples were placed in a tensile tester (Shenzhen SANS Testing Machine Co., Ltd.) and the initial adhesive strength was measured at a peel speed of 300 mm / min. The initial adhesive strength after 2 minutes was measured three times each and the average value was recorded. An initial adhesive strength of 0.2 N / inch or greater at 10 minutes in 100% cohesive failure mode is acceptable. The "cohesive failure mode" referred to here refers to a state in which the adhesive splits apart and some of the adhesive remains attached to each bonded surface. A failure mode in which the adhesive is cleanly removed from the substrate is called the "adhesive failure mode." Adhesives with a cohesive failure mode are considered to be more robust than adhesives with an adhesive failure mode.

[0097] The laminate samples were cured for 10 minutes at 23°C and 50% relative humidity. The initial bond strength of the cured laminate samples was measured according to JIS L1093 method A-1. The initial bond strength after 10 minutes was measured three times and the average value was recorded. An initial bond strength of 0.2 N / inch or greater at 10 minutes in 100% cohesive failure mode is acceptable.

[0098] Opening hours 10 g of the adhesive composition prepared as above was coated on paper at 130°C with an automatic film applicator (Elecometer 4340) to a thickness of 100 μm. A stripe of paper measuring 2.5 cm × 10 cm was attached to the coated paper by pressing with a finger every 10 to 30 seconds. The open time was defined as the time until fiber breakage of the paper stripe was observed. Adhesive compositions with open times of 1 minute to more than 20 minutes were acceptable.

[0099] Inventive Example 1 and Comparative Examples 1-3 In this series of examples, one moisture-curable polyurethane reactive hot melt adhesive composition of the present invention (Example 1) and three compositions in which component (B) of the present invention is replaced with other resins (Comparative Example 1 to Comparative Example 3) were prepared based on the weight percentages specified in Table 1.

[0100] [Table 1]

[0101] As can be seen from Table 1, the compositions of Comparative Examples 1 to 3, which contained resins other than component (B), had compatibility problems, but the composition of the present invention (Example 1) showed excellent performance.

[0102] Inventive Examples 2-4 and Comparative Examples 4-5 In this series of examples, moisture-curable polyurethane reactive hot melt adhesive compositions of the present invention (Examples 2-4) and two compositions having component (B) outside the claimed weight percentages of the present invention (Comparative Examples 4-5) were prepared based on the weight percentages specified in Table 2.

[0103] [Table 2]

[0104] As can be seen from Table 2, compositions having component (B) outside the claimed weight percent of the present invention (Comparative Example 4-Comparative Example 5) exhibited near zero open time or unacceptable initial bond strength at 2 and 10 minutes, while the compositions of the present invention (Examples 2-4) exhibited superior performance.

[0105] Inventive Examples 5-7 and Comparative Example 6 In this series of examples, moisture-curable polyurethane reactive hot melt adhesive compositions having component (B) with different weight average molecular weights (Mw) were prepared based on the weight percentages specified in Table 3.

[0106] [Table 3]

[0107] As the test results in Table 3 show, the adhesive composition containing component (B) with a weight average molecular weight (Mw) of 100,000 g / mol (Comparative Example 6) underwent phase separation.

[0108] These and other modifications and variations of the present invention may be implemented by those skilled in the art without departing from the spirit and scope of the present invention. Additionally, it should be understood that aspects of the various embodiments may be interchanged in whole or in part. Furthermore, those skilled in the art will appreciate that the foregoing description is for illustrative purposes only and is not intended to limit the invention as further described in the appended claims.

Claims

1. At least one reactive polyurethane prepolymer obtained by reacting a reactant mixture comprising (A), (a) at least one polyol, and (b) at least one polyisocyanate having at least two isocyanate groups per molecule; (B) at least one vinyl acetate homopolymer having a weight average molecular weight (Mw) of 15,000 to less than 100,000 g / mol and present in an amount of less than 70 wt. %, based on the total weight of the adhesive composition; 1. A moisture-curable polyurethane hot melt adhesive composition comprising:

2. 2. The moisture-curable polyurethane hot melt adhesive composition of claim 1, wherein reactant (a) is selected from polyester polyols, polyether polyols, and combinations thereof.

3. 3. The moisture-curable polyurethane hot melt adhesive composition according to claim 2, wherein the polyester polyol used as reactant (a) is selected from solid polyester polyols, liquid polyester polyols, and combinations thereof, preferably selected from crystalline polyester polyols, amorphous polyester polyols, liquid polyester polyols, and combinations thereof.

4. The moisture-curable polyurethane hot melt adhesive composition according to claim 3, wherein the polyester polyol used as reactant (a) has a number molecular weight (Mn) of 800 to 20,000 g / mol, preferably 1,000 to 10,000 g / mol, more preferably 1,000 to 5,000 g / mol.

5. 3. The moisture-curable polyurethane hot melt adhesive composition of claim 2, wherein the polyether polyol used as reactant (a) is selected from polytetramethylene ether glycol, poly(oxypropylene) glycol, polyethylene oxide, polybutylene oxide and ethylene oxide endcapped versions of any of the foregoing, and combinations thereof, preferably selected from polytetramethylene ether glycol, poly(oxypropylene) glycol, ethylene oxide endcapped poly(oxypropylene) glycol, and combinations thereof.

6. The reactant (b) is 4,4'-diphenylmethane diisocyanate (MDI), hydrogenated MDI (H12MDI), partially hydrogenated MDI (H6MDI), xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), 4,4-diphenyldimethylmethane diisocyanate, dialkylene diphenylmethane diisocyanate, tetraalkylene diphenylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, 1 ,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, isomers of toluylene diisocyanate (TDI), 1-methyl-2,4-diisocyanatocyclohexane, 1,6-diisocyanato-2,2,4-trimethylhexane, 1,6-diisocyanato-2,4,4-trimethylhexane, 1-isocyanatomethyl-3-isocyanato-1,5,5-trimethylcyclohexane (IPDI), tetramethoxybutane-1,4-diiso cyanate, naphthalene-1,5-diisocyanate (NDI), butane-1,4-diisocyanate, hexane-1,6-diisocyanate (HDI), dicyclohexylmethane diisocyanate, 2,2,4-trimethylhexane-2,3,3-trimethylhexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, ethylene diisocyanate, methylenetriphenyl triisocyanate (MIT), phthalic acid bisisocyanate 2. The moisture-curable polyurethane hot melt adhesive composition of claim 1, wherein the diisocyanate is selected from the group consisting of trimethylhexamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,4-diisocyanatobutane, 1,12-diisocyanatododecane, dimer fatty acid diisocyanate, lysine ester diisocyanate, 4,4-dicyclohexylmethane diisocyanate, 1,3-cyclohexane or 1,4-cyclohexane diisocyanate, and combinations thereof.

7. The moisture-curable polyurethane hot melt adhesive composition according to any one of claims 1 to 6, wherein component (B) has a weight average molecular weight (Mw) in the range of 30,000 to 60,000 g / mol, more preferably 45,000 to 55,000 g / mol.

8. The moisture-curable polyurethane hot adhesive composition according to any one of claims 1 to 6, wherein the adhesive composition is selected from the group consisting of strongly basic amides, triethylamine, tributylamine, dimethylbenzylamine, N-ethyl-, N-methyl-, N-cyclohexylmorpholine, dimethylcyclohexylamine, dimorpholinodiethyl ether, 2-(dimethylaminoethoxy)-ethanol, 1,4-diazabicyclo[2,2,2]octane, 1-azabicyclo[3,3,0]octane, N,N,N',N'-tetramethylethylenediamine ...

7. The moisture-curable polyurethane hot melt adhesive composition according to claim 1, further comprising at least one catalyst (C) selected from N,N'-tetramethylbutanediamine, N,N,N',N'-tetramethylhexane-1,6-diamine, pentamethyldiethylenetriamine, tetramethyldiaminoethyl ether, bis-(dimethylaminopropyl)-urea, N,N'-dimethylpiperazine, 1,2-dimethylimidazole, di-(4-N,N-dimethylaminocyclohexyl)methane, organometallic compounds, and combinations thereof.

9. The moisture-curable polyurethane hot melt adhesive composition according to any one of claims 1 to 6, wherein the adhesive composition hot melt further comprises (D) at least one additive.

10. 7. The moisture-curable polyurethane hot melt adhesive composition according to any one of claims 1 to 6, wherein reactant (a) is present in an amount of from 20 wt% to 85 wt%, more preferably from 40 wt% to 80 wt%, based on the total weight of the adhesive composition.

11. The moisture-curable polyurethane hot melt adhesive composition according to any one of claims 1 to 6, wherein reactant (b) is present in an amount of 5% to 25% by weight, preferably 10% to 20% by weight, based on the total weight of the adhesive composition.

12. 7. The moisture-curable polyurethane hot melt adhesive composition according to any one of claims 1 to 6, wherein component (B) is present in an amount of preferably 1 wt.% to 60 wt.%, preferably 5 wt.% to 45 wt.%, based on the total weight of the adhesive composition.

13. A cured product of the reactive hot melt adhesive composition according to any one of claims 1 to 12.

14. A laminate comprising a first substrate, a second substrate, and an adhesive layer sandwiched therebetween, wherein the first and second substrates are independently selected from glass, resin, textile, wood, and metal, and the adhesive layer is formed by curing the adhesive composition according to any one of claims 1 to 12.

15. Use of the reactive hot melt adhesive composition according to any one of claims 1 to 12 in the manufacture of consumer goods, automotive parts, electronic equipment, and household appliances.

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