Polyol compound and adhesive composition prepared using the same

Abstract

Novel polyol compounds are provided that are represented by Formula I. Polyurethane adhesive compositions containing the polyol compounds can produce adhesive bonds that exhibit excellent adhesive strength and heat seal strength, which is not substantially reduced by changing the weight ratio between the isocyanate component and the polyol component. Methods for preparing the polyol compounds and the adhesive compositions, as well as laminated articles prepared with the adhesive compositions, are provided. [Formula 1] JPEG2023537182000011.jpg18128

Description

[Technical Field]

[0001] The present disclosure relates to novel polyol compounds and methods for preparing them, adhesive compositions containing the polyol compounds and methods for preparing them, and laminated products containing adhesive layers derived from the adhesive compositions and methods for preparing them. The adhesive layers prepared with the adhesive compositions exhibit high resistance to changes in composition and can achieve good adhesive strength and heat seal strength that are not substantially reduced by changes in the weight ratio between the isocyanate component and the polyol component. [Background technology]

[0002] Adhesive compositions are useful in a wide variety of applications. For example, they can be used to bond substrates such as polyethylene, polypropylene, polyester, polyamide, metal, paper, or cellophane to form composite films, i.e., laminates. The use of adhesives in a variety of laminating end-use applications is generally known. For example, adhesives can be used in the manufacture of film / film and film / foil laminates used in the packaging industry.

[0003] Laminating adhesives are widely used in the manufacture of laminates. Among the many well-known systems, polyurethane-based laminating adhesives are preferred due to their many desirable properties, including good adhesion, peel strength, heat seal strength, and resistance to aggressive fillers. Nevertheless, two-component polyurethane-based adhesives consistently face customer complaints regarding ink compatibility issues due to the presence of residual active hydrogen in the ink, which can consume the NCO groups in component A. This leads to discrepancies between the actual and designed mixing ratios, leaving the adhesive in an uncured or tacky state. Furthermore, the actual mixing ratio may be inaccurate due to operational or general errors, leading to poor performance. To address this issue, it is desirable to develop a robust adhesive that can maintain good performance over a wide mixing ratio tolerance range.

[0004] After sustained research, we have surprisingly developed novel polyol compounds that can be used in polyurethane adhesive compositions to achieve one or more of the above goals. Summary of the Invention

[0005] The present disclosure provides unique polyol compounds and polyurethane adhesive compositions containing same.

[0006] In a first aspect of the disclosure, the disclosure provides a polyol compound having a structure represented by formula I:

[0007] [ka] wherein R1 is a linear C2-C alkyl group unsubstituted or substituted with at least one pendant group selected from the group consisting of C1-C5 alkyl, C1-C5 alkoxy, hydroxyl, halogen, and combinations thereof. 10R3 and R4 are the same or different and independently represent a C2-C8 alkyl group substituted with at least two primary hydroxyl groups; n is 6, 7, 8, 9, 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 120, 130, 140, 150, 160, 180, 190, 210, 220, 230, 240, 250, 260, 270, 280, 310, 320, 330, 340, 350, 360, 370, 380, 390, 410, 420, 430, 440, 450, 460, 470, 480, 490, 510, 520, 530, 540, 550, 560, 570, 580, 590, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700, 710, 720, 730, 740, 750, 760, 770, 780, 790, 800, 810, 820, 830, 840, 850, 860, 870, 880, 890, 9

[0023] R1 is an integer between 5 and 500, such as 0, 190, 200, 210, 220, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 500, or within a range of values ​​obtained by combining any two of the above integers. According to a preferred embodiment of the present disclosure, R1 is an unsubstituted linear C3-C6 alkylene group. According to another preferred embodiment of the present disclosure, R2 is one of an ethylene group, a propylene group, or a butylene group, or a combination thereof.

[0008] According to a more preferred embodiment of the present disclosure, R3 and R4 are the same as or different from each other and are independently represented by Formula II.

[0009] [ka] wherein each of R5, R6, and R7 is independently selected from the group consisting of hydrogen, hydroxyl, C1-C4 alkyl, C1-C4 alkoxy, and (hydroxyl)C1-C4 alkylene, with the proviso that each of R3 and R4 contains at least two primary hydroxyl groups, and the asterisk indicates the position at which the moiety represented by Formula II is attached to the remainder of the polyol compound represented by Formula I.

[0010] According to a preferred embodiment of the present disclosure, R3 and R4 are the same as or different from each other and are independently selected from the group consisting of 2,2-di(methylol)ethyl, 2,2-di(methylol)propyl, 2,2-di(methylol)butyl, and 2,2,2-tri(methylol)ethyl. According to a preferred embodiment of the present disclosure, all hydroxyl groups in R3 and R4 are primary hydroxyl, and neither R3 nor R4 contains a secondary or tertiary hydroxyl.

[0011] In a second aspect of the present disclosure, the present disclosure provides a method for preparing a dicarboxylic acid compound represented by HOC(O)-R-COOH or an anhydride thereof by the reaction of HO-[R-O] n ii) reacting the intermediate compound with a hydroxyl-substituted C2-C8 alkane having at least two primary hydroxyl groups to form the polyol compound, wherein R1 is a linear C2-C8 alkane unsubstituted or substituted with at least one pendant group selected from the group consisting of C1-C5 alkyl, C1-C5 alkoxy, hydroxyl, halogen, and combinations thereof. 10 alkylene group, where R2 is a straight-chain C2-C8 alkylene group unsubstituted or substituted with at least one pendant group selected from the group consisting of C1-C5 alkyl, C1-C5 alkoxy, hydroxyl, halogen, and combinations thereof, and n is an integer from 5 to 500. Preferably, the hydroxyl-substituted C2-C8 alkane is selected from the group consisting of trimethylolmethane, trimethylolethane, trimethylolpropane, pentaerythritol, and combinations thereof.

[0012] In a third aspect of the present disclosure, the present disclosure provides an adhesive composition comprising: (A) an isocyanate component comprising a prepolymer having at least two free isocyanate groups; and (B) a polyol component comprising a polyol compound of the present disclosure. According to a preferred embodiment, the prepolymer having at least two free isocyanate groups can be prepared by reacting an isocyanate compound, such as a monomeric isocyanate compound having at least two isocyanate groups, with a polyol, such as a polyol compound of the present disclosure.

[0013] Preferably, the adhesive composition comprises any one or any combination of the following characteristics: the adhesive composition may be solvent-free or may contain a solvent; the polyol compound has a hydroxyl functionality of at least 3, or at least 4; the polyol compound has a hydroxyl functionality of 4.0 to 8.0, such as 4.0, or 5.0, or 6.0, or 7.0, or 8.0; the polyol component is selected from the group consisting of polycarbonate polyols, polyether polyols, polyester polyols, and combinations thereof, other than the polyol compound. The second polyol has a hydroxyl functionality of at least 1.2, or at least 1.5, or at least 1.6, or at least 1.8, or at least 2.0, or at least 2.2, or at least 2.5, or at least 2.8, or at least 3.0, and the polyol component does not include a polyol having a hydroxyl functionality of less than 1.2, or less than 1.5, or less than 2.0, or less than 3.0, and the content of the polyol compound is 40% by weight to 80% by weight, and the content of the second polyol is and the (A) isocyanate component has an average isocyanate functionality greater than 1.1, such as at least 1.5, or at least 1.8, and can be up to 6.0, or up to 5.5, or up to 5.0, or up to 4.5, or up to 4.0, or up to 3.5, or up to 3.0, or up to 2.5, or up to 2.0, or up to 1.8, or up to 1.5, and the (A) isocyanate component prepolymer has an average isocyanate functionality greater than 1.1, such as at least 1.5, or at least 1.8. and may be up to 6.0, or up to 5.0, or up to 4.0, or up to 3.0, or up to 2.0, all of the hydroxyl groups contained in the polyol compound of the present disclosure are primary hydroxyl groups, all of the hydroxyl groups contained in the polyol component are primary hydroxyl groups, the polyol compound has a number average molecular weight Mn of at least 300, such as 400 to 3,000, or 400 to 2,000, or 400 to 1,000, and the weight ratio between the isocyanate component (A) and the polyol component (B) is 100:30 to 100:100.

[0014] In a fourth aspect of the present disclosure, the present disclosure provides a method for preparing an adhesive composition of the present disclosure, the method comprising: (I) providing an isocyanate compound; (II)i) A dicarboxylic acid compound represented by HOC(O)-R1-COOH or its anhydride is converted into HO-[R2-O] n ii) reacting the intermediate compound with a hydroxyl-substituted C2-C8 alkane having at least two primary hydroxyl groups to form the polyol compound, wherein R1 is a linear C2-C8 alkane unsubstituted or substituted with at least one pendant group selected from the group consisting of C1-C5 alkyl, C1-C5 alkoxy, hydroxyl, halogen, and combinations thereof. 10 R2 is a C2-C8 alkylene group unsubstituted or substituted with at least one pendant group selected from the group consisting of C1-C5 alkyl, C1-C5 alkoxy, hydroxyl, halogen, and combinations thereof, and n is an integer from 5 to 500; and iii) optionally, blending the polyol compound with a second polyol other than the polyol compound, the second polyol being selected from the group consisting of polycarbonate polyol, polyether polyol, polyester polyol, and combinations thereof, wherein the isocyanate component and the polyol component are stored and shipped in separate packages.

[0015] According to various embodiments of the present disclosure, the adhesive composition is a two-component adhesive, where the isocyanate component and the polyol component are stored and shipped in separate packages and are combined immediately prior to application to any object.

[0016] In a fifth aspect of the present disclosure, the present disclosure provides a method for preparing a laminate article using an adhesive composition of the present disclosure, the method comprising the steps of providing a first substrate and a second substrate, mixing an isocyanate component with a polyol component to form a curable mixture, adhering the first substrate to the second substrate by using a layer of the curable mixture, and curing or allowing the curable mixture to cure.

[0017] In a sixth aspect of the present disclosure, the present disclosure provides a laminated article comprising at least two substrates and an adhesive layer sandwiched therebetween, the adhesive layer being formed by a reaction between an (A) isocyanate component and a (B) polyol component of the adhesive composition.

[0018] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed. [Brief explanation of the drawings]

[0019] [Figure 1] 1 shows a two-step reaction mechanism for preparing a polyol compound according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Additionally, all publications, patent applications, patents, and other references mentioned herein are incorporated by reference.

[0021] As disclosed herein, "and / or" means "and, or alternatively." All ranges are inclusive of the endpoints unless otherwise indicated.

[0022] As disclosed herein, unless otherwise indicated, the term "polyol compound" or "polyol compound according to the present disclosure" refers specifically to novel polyol compounds developed according to the present disclosure.

[0023] According to various embodiments of the present disclosure, the adhesive composition is a "two-part" or "two-package" composition comprising an isocyanate component (A) and a polyol component (B) comprising a polyol compound of the present disclosure, which is prepared by a two-step reaction: (i) reacting a dicarboxylic acid with a first polyol to obtain a carboxyl-terminated intermediate compound, and (ii) reacting the intermediate compound with a hydroxyl-substituted C2-C8 alkane having at least two primary hydroxyl groups. The specifically defined polyol compound can appropriately impart desirable properties to the adhesive composition and adhesive layers prepared therefrom. According to a preferred embodiment, the isocyanate component (A) and the polyol component (B) are transported and stored separately and combined immediately before or just before application during the manufacture of laminated articles.

[0024] Isocyanate component (A) According to embodiments of the present disclosure, the isocyanate component (A) has an average NCO functionality of at least about 1.5, preferably from about 2 to about 10, more preferably from about 2 to about 8, more preferably from about 2 to about 6, and most preferably about 2. Preferably, the isocyanate component (A) has an average NCO functionality of 2.0.

[0025] According to a preferred embodiment, the prepolymer contained in the isocyanate component is formed by the reaction of (i) one or more isocyanate compounds containing at least two isocyanate groups, preferably two isocyanate groups, with (ii) one or more isocyanate-reactive compounds having at least two isocyanate-reactive groups, and the prepolymer contains at least two free isocyanate groups, preferably two free isocyanate groups. According to a preferred embodiment, the isocyanate compound used to prepare the prepolymer is a C4-C6 isocyanate compound containing at least two isocyanate groups. 12 Aliphatic isocyanates, C6-C containing at least two isocyanate groups 15 Alicyclic or aromatic isocyanates, C7-C containing at least two isocyanate groups 15 and combinations thereof, more preferably selected from the group consisting of m-phenylene diisocyanate, 2,4-toluene diisocyanate and / or 2,6-toluene diisocyanate (TDI), various isomers of diphenylmethane diisocyanate (MDI), carbodiimide-modified MDI products, hexamethylene-1,6-diisocyanate, tetramethylene-1,4-diisocyanate, cyclohexane-1,4-diisocyanate. , hexahydrotoluene diisocyanate, hydrogenated MDI, naphthylene-1,5-diisocyanate, isophorone diisocyanate (IPDI), and isomers of naphthalene-dipolyisocyanate ("NDI"), such as 1,5-NDI, isomers of hexamethylene dipolyisocyanate ("HDI"), isophorone dipolyisocyanate ("IPDI"), isomers of xylene dipolyisocyanate ("XDI"), or mixtures thereof. According to another preferred embodiment of the present disclosure, the isocyanate-reactive compound used to prepare the above prepolymer is selected from the group consisting of C2-C hydroxyl groups containing at least two hydroxyl groups. 16 Aliphatic polyhydric alcohols, C6-C containing at least two hydroxy groups 15 Alicyclic or aromatic polyhydric alcohols, C7-C containing at least two hydroxy groups15 The prepolymer may be prepared from a monomeric polyfunctional alcohol, such as an araliphatic polyol, or a polymeric polyol, such as a polyester polyol, a polyether polyol, a polycarbonate polyol, a blend of the polyester polyol and the polyether polyol, or a combination thereof. According to a preferred embodiment of the present application, the isocyanate-reactive compound used to prepare the prepolymer is one of the above-described monomeric polyols having a hydroxyl functionality of 2.0. According to another preferred embodiment of the present application, the isocyanate-reactive compound used to prepare the prepolymer is one of the above-described monomeric polyols having a hydroxyl functionality of 2.0, more preferably a polyester polyol having a hydroxyl functionality of 2.0. According to one embodiment of the present disclosure, the polyester polyol may have a number average molecular weight of about 200 to 5,000 g / mol, such as 300 to 3,000 g / mol, or 400 to 2,000 g / mol. According to a preferred embodiment of the present disclosure, the polyester polyol has two terminal hydroxyl groups attached to the main chain end and does not contain any pendant hydroxyl groups, more preferably does not contain any pendant groups. According to another embodiment of the present disclosure, the isocyanate-reactive compound having at least two isocyanate-reactive groups can be the polyol compound of the present disclosure.

[0026] In one embodiment of the present disclosure, the isocyanate component (A) includes only a prepolymer and does not include any other isocyanate compounds.

[0027] In some embodiments of the present disclosure, the isocyanate component (A) further comprises one or more monomeric isocyanate compounds used in combination with the above prepolymers; suitable monomeric isocyanate compounds may include aromatic, aliphatic, cycloaliphatic, and araliphatic monomeric isocyanates having two or more isocyanate groups; such isocyanate compounds are C4-C6 isocyanates containing at least two isocyanate groups. 12Aliphatic isocyanates, C6-C containing at least two isocyanate groups 15 Cycloaliphatic or aromatic isocyanates, C7-C containing at least two isocyanate groups 15 and combinations thereof, preferably selected from the group consisting of m-phenylene diisocyanate, 2,4-toluene diisocyanate and / or 2,6-toluene diisocyanate (TDI), various isomers of diphenylmethane diisocyanate (MDI), carbodiimide-modified MDI products, hexamethylene-1,6-diisocyanate, tetramethylene-1,4-diisocyanate, cyclohexane-1,4-diisocyanate, cyanate, hexahydrotoluene diisocyanate, hydrogenated MDI, naphthylene-1,5-diisocyanate, isophorone diisocyanate (IPDI) and isomers of naphthalene-dipolyisocyanate ("NDI") such as 1,5-NDI, isomers of hexamethylene dipolyisocyanate ("HDI"), isophorone dipolyisocyanate ("IPDI"), isomers of xylene dipolyisocyanate ("XDI"), or mixtures thereof.

[0028] Compounds having isocyanate groups, such as the prepolymers described above, and additional monomeric isocyanate compounds, may be characterized by the parameter "%NCO," which is the amount of isocyanate groups by weight based on the weight of the compound. The parameter %NCO may be measured by the method of ASTM D 2572-97(2010). According to embodiments of the present disclosure, the prepolymers and monomeric isocyanate compounds have a %NCO of at least 3 wt%, or at least 5 wt%, or at least 7 wt%. In some embodiments, the isocyanate compounds have a %NCO of no more than 40 wt%, 35 wt%, 30 wt%, 25 wt%, 22 wt%, or 20 wt%.

[0029] According to one embodiment of the present disclosure, the content of the isocyanate compound used to prepare the prepolymer is 30% to 65% by weight, and the total weight of the isocyanate component (A) is 100% by weight. According to a preferred embodiment of the present disclosure, the content of the isocyanate compound used to prepare the prepolymer may be within a numerical range obtained by combining any two of the following endpoint values: 27% by weight, 30% by weight, 33% by weight, 35% by weight, 40% by weight, 45% by weight, 50% by weight, 55% by weight, 60% by weight, 65% by weight, and 70% by weight. According to another preferred embodiment of the present disclosure, the content of the isocyanate-reactive compound for preparing the prepolymer may be within a numerical range obtained by combining any two of the following endpoint values: 8% by weight, 10% by weight, 12% by weight, 15% by weight, 18% by weight, 20% by weight, 22% by weight, 25% by weight, 28% by weight, 30% by weight, 32% by weight, 35% by weight, 37% by weight, 40% by weight, 42% by weight, 45% by weight, 48% by weight, 50% by weight, 52% by weight, 54% by weight, 55% by weight, 57% by weight, 60% by weight, 62% by weight, 65% by weight, 67% by weight, 70% by weight, 72% by weight, 75% by weight, 80% by weight, 82% by weight, and 85% by weight, where the total weight of the isocyanate component (A) is 100% by weight.

[0030] Polyol component (B) According to various embodiments of the present disclosure, the polyol component comprises the unique polyol compounds of the present application prepared by (i) reacting a dicarboxylic acid with a first polyol to obtain an intermediate compound terminated with carboxyl groups, and (ii) reacting the intermediate compound with a compound having multiple primary hydroxyl groups.

[0031] According to various embodiments of the present disclosure, the dicarboxylic acid may be represented by the general formula HOC(O)-R1-COOH, where R1 is an alkylene group containing 1 to 10 carbon atoms, preferably the number of carbon atoms in R1 is an integral of 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. According to preferred embodiments of the present disclosure, the dicarboxylic acid is selected from the group consisting of adipic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, phthalic anhydride, and any combination thereof.

[0032] According to various embodiments of the present disclosure, the first polyol can be a polyether polyol derived from ethylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyalkylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, triol, tetraol, or a combination thereof. The first polyol may further include optional copolymerized units derived from polycarbonate polyol, polyester polyol, or a combination thereof. According to a preferred embodiment of the present disclosure, the first polyol is a polyether polyol such as polyethylene glycol or polypropylene glycol. According to another preferred embodiment of the present disclosure, the first polyol is a polyethylene glycol or polypropylene glycol having a number average molecular weight Mn of at least 200, or at least 300, or at least 400 g / mol. According to another preferred embodiment of the present disclosure, the first polyol is a polyethylene glycol or polypropylene glycol having a hydroxyl functionality of 2.0 and containing two hydroxyl end groups attached to the backbone end, i.e., no pendant hydroxyl groups.

[0033] The mechanism of the reaction between a dicarboxylic acid and a first polyol is shown in FIG. 1, where the ratio of the dicarboxylic acid to the first polyol is controlled so that the resulting intermediate compound is terminated with both carboxyl groups at the main chain ends. According to a preferred embodiment of the present disclosure, the first polyol is a polyether polyol containing two terminal hydroxyl groups, and the molar ratio between the dicarboxylic acid and the first polyol is 2:1. According to a preferred embodiment as shown in FIG. 1, the first polyol is PEG-400, i.e., polyethylene glycol having a number-average molecular weight of about 400 g / mol. According to various embodiments of the present disclosure, the first polyol is a poly(alkylene oxide) (e.g., polyethylene oxide, polypropylene oxide, polybutylene oxide, and blends or copolymers thereof) having a degree of polymerization of 5 to 500, such as 6 to 400, or 8 to 300, or 10 to 200, or 12 to 100, or within a numerical range obtained by combining any two of the above endpoints. According to an alternative embodiment of the present disclosure, the first polyol may have the following endpoint values: 200 g / mol, 300 g / mol, 400 g / mol, 500 g / mol, 600 g / mol, 700 g / mol, 800 g / mol, 900 g / mol, 1,000 g / mol, 1,200 g / mol, 1,500 g / mol, 1,800 g / mol, 2,000 g / mol, 2,200 g / mol, 2,500 g / mol, 3,000 g / mol, 4,000 g / mol, 5,000 g / mol, 6,000 g / mol, 7,000 g / mol, 8,000 g / mol, 9,0 ...0,000 g / mol, 11,000 g / mol, 12,000 g / mol, 13,000 g / mol, 14,000 g / mol, 15,000 g / mol, 16,000 g / mol, 17,000 g / mol, 18,000 g / mol, 19,000 g / mol, 21,000 g / mol, 22,000 g / mol, 23,000 g / mol, 24 The polyether polyol may have a number average molecular weight Mn within a numerical range obtained by combining any two of 2,800 g / mol, 3,000 g / mol, 3,200 g / mol, 3,500 g / mol, 3,800 g / mol, 4,000 g / mol, 4,200 g / mol, 4,500 g / mol, 4,800 g / mol, and 5,000 g / mol.

[0034] The intermediate compound is then reacted with a compound containing at least two primary hydroxyl groups, such as trimethylolmethane, trimethylolethane, trimethylolpropane, or pentaerythritol, preferably in a molar ratio of at least 1:2, more preferably in a molar ratio of 1:2, to form the polyol compound of the present disclosure. According to a preferred embodiment of the present disclosure, the polyol compound of the present disclosure is a hydroxyl-terminated high-functionality polyester polyol having a hydroxyl functionality of at least 3, or at least 3.5, or at least 4.0, or at least 4.5, or at least 5.0, or at least 5.5, or at least 6.0, more preferably 4.0. Preferably, all hydroxyl groups contained in the high-functionality polyol compound are primary hydroxyl groups, i.e., the high-functionality polyol compound of the present disclosure does not contain secondary or tertiary hydroxyl groups.

[0035] According to a preferred embodiment of the present disclosure, the polyol component does not include any polyol other than the polyol compound of the present disclosure. According to a more preferred embodiment of the present disclosure, the polyol component further includes a second polyol other than the polyol compound, the second polyol being selected from the group consisting of polycarbonate polyol, polyether polyol, polyester polyol, and combinations thereof. According to a more preferred embodiment of the present disclosure, the second polyol has a number average molecular weight Mn within a range obtained by combining any two of the following endpoint values: 200 g / mol, 300 g / mol, 400 g / mol, 500 g / mol, 600 g / mol, 700 g / mol, 800 g / mol, 900 g / mol, 1,000 g / mol, 1,200 g / mol, 1,500 g / mol, 1,800 g / mol, 2,000 g / mol, 2,200 g / mol, 2,500 g / mol, 2,800 g / mol, 3,000 g / mol, 3,200 g / mol, 3,500 g / mol, 3,800 g / mol, 4,000 g / mol, 4,200 g / mol, 4,500 g / mol, 4,800 g / mol, and 5,000 g / mol. According to a more preferred embodiment of the present disclosure, the second polyol is a hydroxyl-terminated polyol having a hydroxyl functionality of at least 1.2, at least 1.5, at least 1.6, at least 1.8, at least 2.0, at least 2.2, at least 2.5, at least 2.8, at least 3, at least 3.5, at least 4.0, at least 4.5, at least 5.0, at least 5.5, or at least 6.0, more preferably 1.5 to 3.0. Preferably, all hydroxyl groups contained in the second polyol are primary hydroxyl groups, i.e., the second polyol does not contain secondary or tertiary hydroxyl groups. According to one embodiment of the present disclosure, the content of the polyol compound is 40% to 80% by weight, and the content of the second polyol is 20% to 60% by weight, based on the total weight of the polyol component (B).

[0036] According to a preferred embodiment of the present application, the polyol compound may be synthesized by an esterification reaction at a temperature of 100°C to 300°C, such as 130°C to 250°C, or 150°C to 230°C, or 160°C to 210°C, at an atmospheric pressure or reduced pressure of 0.001 to 1 bar, such as 0.01 to 0.9 bar, or 0.1 to 0.9 bar, or 0.2 to 0.9 bar, or 0.3 to 0.9 bar, or 0.5 to 0.9 bar, or 0.8 to 0.9 bar, for a duration of 10 minutes to 10 hours, or 0.5 hours to 8 hours, or 1 hour to 5 hours, or 1.5 to 4 hours, or 2 to 3 hours, in the presence or absence of an esterification catalyst, such as an alkali catalyst or an acid catalyst.

[0037] Application of the adhesive composition According to various embodiments of the present disclosure, the two-component adhesive composition of the present disclosure may include one or more solvents or may be completely solvent-free. As disclosed herein, the terms "solvent-free," "solvent-free," or "non-solvent" may be used interchangeably, and shall be understood to mean that the mixture of all ingredients used to prepare the adhesive composition contains less than 3 wt. %, preferably less than 2 wt. %, preferably less than 1 wt. %, more preferably less than 0.5 wt. %, more preferably less than 0.2 wt. %, more preferably less than 0.1 wt. %, more preferably less than 100 ppm by weight, more preferably less than 50 ppm by weight, more preferably less than 10 ppm by weight, and more preferably less than 1 ppm by weight of any organic or inorganic solvent, based on the total weight of the mixture of ingredients. As disclosed herein, the term "solvent" refers to organic and inorganic liquids that simply dissolve one or more solid, liquid, or gaseous materials without causing any chemical reaction. In other words, some organic compounds, such as ethylene glycol and propylene glycol, which are generally considered "solvents" in polymerization technology, as well as water, do not belong to the "solvent" category, even though they are used in the preparation of two-component polyurethane adhesive compositions, since they primarily function as isocyanate-reactive functional substances or chain extenders, etc., by undergoing chemical reactions.

[0038] According to various embodiments of the present disclosure, the weight ratio between the isocyanate component (A) and the polyol component (B) is 100:30 to 100:100. According to preferred embodiments, the weight ratio may be within a numerical range obtained by combining any two of the following ratios: 100:30, 100:40, 100:50, 100:60, 100:70, 100:80, 100:90, and 100:100. According to a preferred embodiment of the present application, the weight ratio of the isocyanate component (A) to the polyol component (B) is adjusted so that the weight ratio of the prepolymer in the isocyanate component (A) to the polyol compound in the polyol component (B) is 100:10 to 100:100, or 100:20 to 100:90, or 100:30 to 100:80, or may be within a numerical range obtained by combining any two of the following ratios: 100:30, 100:40, 100:45, 100:50, 100:55, 100:60, 100:65, 100:70, 100:75, and 100:80. One technical advantage of the present disclosure is that the adhesive strength and heat seal strength of the (cured) adhesive prepared by using the adhesive composition of the present disclosure are not substantially reduced by changing the above ratio. For example, the variation in the magnitude of the adhesive strength and heat seal strength (with or without the BIB (boil-in-bag) test) of the (cured) adhesive prepared by using the adhesive composition is less than ±20%, or less than ±15%, or less than ±10%, or less than ±8%, or less than ±6%, or less than ±5%, or less than ±3%, or less than ±2%, or less than ±1%, or less than ±0.5%. When the weight ratio between the isocyanate compound (especially a prepolymer containing at least two isocyanate groups) in the isocyanate component (A) and the polyol compound in the polyol component varies from 100:50 to 100:80, or from 100:50 to 100:40 or 100:45, the adhesive strength and heat seal strength of the (cured) adhesive prepared by using the adhesive composition having a ratio of 100:50 is taken as 100%.

[0039] As described above, the isocyanate component (A) and the polyol component (B) are transported and stored separately and combined immediately before or immediately before application during the manufacture of laminated articles. In some embodiments, both the isocyanate component and the polyol component are liquid at ambient temperature. When it is desired to use the adhesive composition, the isocyanate component and the polyol component are contacted and mixed together. Upon mixing, a polymerization (cure) reaction occurs between the free isocyanate groups of the isocyanate component (A) and the hydroxyl groups of the polyol component (B), forming a polyurethane that functions as an adhesive in an adhesive layer between two or more substrates. The adhesive composition formed by contacting the two components may be referred to as a "curable mixture."

[0040] Optionally, one or more catalysts may be used to promote or accelerate the above polymerization reaction to prepare the prepolymer in isocyanate component (A) and / or the polymerization between the prepolymer of (A) and polyol component (B).

[0041] The catalyst may include any substance capable of promoting the reaction between the isocyanate group and the hydroxyl group. Without being limited by theory, examples of the catalyst include glycine salts, tertiary amines, tertiary phosphines such as trialkylphosphines and dialkylbenzylphosphines, morpholine derivatives, piperazine derivatives, acetylacetone, benzoylacetone, trifluoroacetylacetone, ethyl acetoacetate, and the like, various metal chelates such as those obtainable from metals such as Be, Mg, Zn, Cd, Pd, Ti, Zr, Sn, As, Bi, Cr, Mo, Mn, Fe, Co, and Ni, acidic metal salts of strong acids such as ferric chloride and stannic chloride, alkali metals, alkaline earth metals, Al, Sn, Pb, Mn, Co, Ni, and Cu, and the like. and organotin compounds such as dialkyltin(IV) salts of organic carboxylic acids, e.g., dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, and dioctyltin diacetate; bismuth salts of organic carboxylic acids, e.g., bismuth octoate; organometallic derivatives of trivalent and pentavalent As, Sb, and Bi, and metal carbonyls of iron and cobalt, or mixtures thereof.

[0042] Generally, the catalyst content used herein is greater than zero and up to 1.0 wt. %, preferably up to 0.5 wt. %, more preferably up to 0.05 wt. %, based on the total weight of all reactants.

[0043] The adhesive compositions of the present disclosure may optionally contain additional adjuvants and / or additives for particular purposes.

[0044] In one embodiment of the present disclosure, one or more of the adjuvants and / or additives may be selected from the group consisting of other co-catalysts, surfactants, toughening agents, flow modifiers, adhesion promoters (such as aminosilanes or epoxysilanes or phosphate esters), diluents, stabilizers, plasticizers, catalysts, deactivators, dispersants, and mixtures thereof.

[0045] Also disclosed is a method for producing a laminated article using the adhesive composition. In some embodiments, the adhesive composition, such as the adhesive composition described above, is in a liquid state. In some embodiments, the composition is liquid at 25°C. Even if the composition is solid at 25°C, it is acceptable to heat the composition to convert it to a liquid state as needed. A layer of the composition is applied to a substrate or film surface. A "substrate / film" is any structure having one dimension equal to or less than 0.5 mm and two other dimensions equal to or greater than 1 cm. A polymer film is a film made from a polymer or a mixture of polymers. The composition of a polymer film is typically one or more polymers in a weight ratio of 80 weight percent or greater. In some embodiments, the layer of curable mixture applied to the film is 1 to 5 μm thick.

[0046] In some embodiments, the surface of another substrate / film is contacted with a layer of the curable mixture to form an uncured laminate. The adhesive composition may be applied by a conventional laminator, such as a Nordmeccanica Labo-Combi 400 machine. The curable mixture is then cured or allowed to cure. The uncured laminate may be pressed, for example, by passing it through nip rollers, which may or may not be heated. The uncured laminate may be heated to accelerate the curing reaction. Suitable substrates / films include paper, woven and nonwoven fabrics, metal foils, polymers, and metal-coated polymers. The film may optionally have a surface on which an image is printed with ink, and the ink may contact the adhesive composition. In some embodiments, the substrate / film is a polymer film or a metal-coated polymer film, more preferably a polymer film.

[0047] The method of the present disclosure may be carried out continuously or batchwise. An example of a continuous process is a roll-to-roll process, in which a roll of a first substrate / film is unwound and sent to two or more workstations where the isocyanate component (A) and the polyol component (B) are mixed to form the adhesive composition (curable mixture) of the present application, which is applied to the surface of the first substrate / film. The adhesive composition (curable mixture) of the present application may be applied two or more times to achieve a desired film thickness or composition profile. A second substrate / film may be applied onto the curable adhesive layer with or without the aid of a roller. A heating or irradiation device may be positioned to promote curing of the coated adhesive layer, and rollers may also be used to increase adhesive strength within the laminate. The second substrate / film may be the same or different from the first substrate / film and may be unwound from a roll. The unwound substrate / film is generally 10 to 20,000 meters, 10 to 15,000 meters, and preferably 20 to 10,000 meters in length and is typically fed at a speed ranging from 0.1 to 60 m / min, preferably from 3 to 45 m / min, and more preferably from 5 to 15 m / min. At the end of the continuous technique, the cured layer product is wound and taken up on a spindle.

[0048] The laminate articles disclosed herein can be cut or otherwise formed to have a shape suitable for any desired purpose, such as packaging.

[0049] Although the final general description and the following examples focus primarily on two-component PU-based adhesive compositions, the unique hydroxyl compounds of the present disclosure may be used as isocyanate-reactive compounds for any other polyurethane-based products, such as coatings, paints, insulating materials, packaging materials, foam materials, etc., to impart the above-mentioned technical advantages to these products. [Example]

[0050] Some embodiments of the present invention are now described in the following examples, in which all parts and percentages are by weight unless otherwise indicated. However, the scope of the present disclosure is not, of course, limited to the formulations shown in these examples. Rather, the examples merely relate to the invention of the present disclosure.

[0051] Information on the raw materials used in the examples is listed in Table 1 below.

[0052] [Table 1]

[0053] Synthetic Examples 1-4: Synthesis of Polyol Compounds of the Present Disclosure (Multiple Primary Hydroxyl-Functionalized Polyester Polyols) One mole of Carbowax™ PEG 400 or Carbowax™ PEG 1000 and two moles of adipic acid were added to a flask equipped with a stirring blade and an oil bath and heated to a temperature of 210°C. The reaction was continued for one hour to produce a carboxyl-terminated intermediate compound. The reaction mixture was cooled to 160°C, and then two moles of trimethylolpropane, pentaerythritol, or glycerol were added thereto. The flask was reheated to 210°C and held there until the mixture in the flask showed an acid value of less than 3.0. The reaction product was then dried at 210°C for one hour under a vacuum of 880 mbar (26 inches of mercury) to achieve an acid value of 1.0 mg KOH / g. The polyester polyols prepared in Synthesis Examples 1 to 3 were designated HF1 to HF4, respectively.

[0054] The resulting products were then characterized for OH number (measured according to ASTM D6342:2008) and viscosity (measured according to GB-T12008.8-1992) and summarized in Table 2.

[0055] [Table 2]

[0056] Examples 1 to 4 and Comparative Examples 1 to 2 As shown in Table 3 below, HF1-HF4 were mixed with VORANOL™ CP450 to form polyol components (B), which were used in inventive Examples 1-4. A comparative polyol component (B) was also prepared by mixing a polyether polyol (VORANOL™ CP450) with a polyester polyol (Bester™ 90) and was used in two comparative examples.

[0057] [Table 3]

[0058] The adhesive compositions of Examples 1-4 and Comparative Examples 1-2 were synthesized according to the formulations listed in Table 4, and their adhesive strength (BS) and heat seal strength (HS) were characterized by using the following techniques.

[0059] [Table 4]

[0060] The polyol components prepared in Table 3 were paired with a commercially available product (NCO prepolymer) from Dow Chemical Company, MorFree™ 698A, in the ratios shown in Table 4 to form adhesives for performance evaluation.

[0061] Laminates were prepared with these adhesives on a Nordmeccanica Labo-Combi400 machine under the following process conditions: line speeds set at 120 mpm and 150 mpm, transfer roller temperature at 45°C, nip temperature set at 60°C and coat weight set at 1.8 gsm. Different substrates were selected to form PET / PE60 test laminate structures which were characterized by the following techniques:

[0062] Test Method Adhesive strength (BS) Laminates prepared with the adhesive composition, PET substrate, and PE60 substrate were cut into 15 mm wide strips for T-peel testing at a crosshead speed of 250 mm / min using a 5940 Series Single Column Table Top System available from Instron Corporation. During the test, the tail of each strip was slightly pulled with a finger to ensure that the tail was maintained at 90 degrees relative to the peel direction. Three strips of each sample were tested, and the average value was calculated. Results were expressed in units of N / 15 mm. Higher values ​​indicate better adhesive strength.

[0063] Heat seal strength (HS) Laminates prepared with the adhesive composition, PET substrate, and PE60 substrate were heat-sealed for 1 second at a sealing temperature of 140°C and a pressure of 300 N in an HSG-C heat sealer available from Brugger Company, then cooled and cut into 15 mm wide strips for heat seal strength testing at a crosshead speed of 250 mm / min using a 5940 Series Single Column Table Top System available from Instron Corporation. Three strips of each sample were tested, and the average value was calculated. Results were expressed in units of N / 15 mm. Higher values ​​indicate better heat seal strength.

[0064] Boil-in-Bag (BiB) The laminate prepared using the adhesive composition was cut into 8 cm x 12 cm pieces and heat-sealed to form bags containing water. The bags were then immersed in boiling water for 30 minutes, during which time the bags remained completely submerged. After boiling for 30 minutes, the bags were inspected for any defects, such as tunneling, delamination, or leakage. If any defects were present, the extent of the defects was recorded. Samples that passed the test showed no evidence of tunneling, delamination, or leakage. The bags were opened, emptied, and cooled, then cut into 15 mm wide strips and tested for their T-peel adhesive strength and heat seal strength in an Instron 5943 machine. Three strips of each sample were tested, and the average values ​​were calculated.

[0065] The adhesive strength, heat seal strength and BiB properties are summarized in Table 5, from which it can be seen that all inventive examples show excellent HS and BS that do not degrade to unacceptable ranges whether the ratio between the two components is changed or not, whereas the comparative examples show a stronger degradation of HS and BS when the ratio of component (A) to component (B) is changed to form a tunnel during the boil-in-bag (BiB) process.

[0066] [Table 5] The inventions described in the original claims of this application are set forth below. [1] A polyol compound having a structure represented by formula I: [ka] In the formula, R 1 But C 1 ~C 5 Alkyl, C 1 ~C 5 a linear C unsubstituted or substituted with at least one pendant group selected from the group consisting of alkoxy, hydroxyl, halogen, and combinations thereof; 1 ~C 10 is an alkylene group, R 2 But C 1 ~C 5 Alkyl, C 1 ~C 5 a linear C unsubstituted or substituted with at least one pendant group selected from the group consisting of alkoxy, hydroxyl, halogen, and combinations thereof;2 ~C 8 is an alkylene group, R 3 and R 4 are the same or different and are substituted with at least two primary hydroxyl groups 2 ~C 8 independently represent alkyl groups, A polyol compound in which n is an integer of 5 to 500. [2] R 3 and R 4 are the same as or different from each other and are independently represented by formula II,

change

[10] The adhesive composition according to [8], in which the content of the polyol compound according to [1] is 40% by weight to 80% by weight, and the content of the second polyol is 20% by weight to 60% by weight, based on the total weight of the polyol component (B).

[11] The weight ratio between the isocyanate component (A) and the polyol component (B) is 100:30 to 100:100; The adhesive composition according to [7], wherein the adhesive composition contains a solvent or is solvent-free.

[12] A method for preparing a laminated article using the adhesive composition according to [7], comprising: providing a first substrate and a second substrate; mixing the (A) isocyanate component with the (B) polyol component to form a curable mixture; adhering the first substrate to the second substrate by using a layer of the curable mixture; and curing or allowing the curable mixture to harden.

[13] A laminated article comprising at least two substrates and an adhesive layer sandwiched therebetween, wherein the adhesive layer is formed by a reaction between the (A) isocyanate component and the (B) polyol component of the adhesive composition according to [7].

Claims

1. A polyol compound having a structure represented by Formula I: 【Chemistry 1】 In the formula, R １ But C １ ~C ５ Alkyl, C １ ~C ５ a linear C unsubstituted or substituted with at least one pendant group selected from the group consisting of alkoxy, hydroxyl, halogen, and combinations thereof; １ ~C １０ is an alkylene group, R ２ But C １ ~C ５ ethylene unsubstituted or substituted with at least one pendant group selected from the group consisting of alkoxy, hydroxyl, halogen, and combinations thereof; R ３ and R ４ are the same as or different from each other and are independently selected from the group consisting of 2,2-di(methylol)ethyl, 2,2-di(methylol)propyl, 2,2-di(methylol)butyl, and 2,2,2-tri(methylol)ethyl; A polyol compound in which n is an integer of 5 to 500.

2. R ３ or R ４ 10. The polyol compound of claim 1, wherein none of the groups in the formula (I) contains a secondary hydroxyl or a tertiary hydroxyl.

3. 3. A method for preparing the polyol compound of claim 1 or 2, comprising: i) HOC(O)-R １ -COOH or its anhydride, ２ -O] ｎ with a poly(alkylene oxide) represented by —H to form an intermediate compound terminated at both ends with carboxylic acid groups; ii) converting the intermediate compound into a hydroxyl-substituted C methylol compound selected from the group consisting of trimethylolmethane, trimethylolethane, trimethylolpropane, pentaerythritol, and combinations thereof; ２ ~C ８ and an alkane to form said polyol compound; In the formula, R １ But C １ ~C ５ Alkyl, C １ ~C ５ a linear C unsubstituted or substituted with at least one pendant group selected from the group consisting of alkoxy, hydroxyl, halogen, and combinations thereof; １ ~C １０ is an alkylene group, R ２ But C １ ~C ５ ethylene unsubstituted or substituted with at least one pendant group selected from the group consisting of alkoxy, hydroxyl, halogen, and combinations thereof; The method wherein n is an integer from 5 to 500.

4. An adhesive composition comprising: (A) an isocyanate component comprising a prepolymer having at least two free isocyanate groups; (B) a polyol component containing the polyol compound according to claim 1; (However, the adhesive composition does not contain a difunctional polymer polyol or a trifunctional polymer polyol.) Adhesive composition.

5. 5. The adhesive composition according to claim 4, wherein the polyol component further comprises at least one second polyol selected from the group consisting of polycarbonate polyols other than the polyol compound according to claim 1, polyether polyols, polyester polyols, and combinations thereof.

6. 5. The adhesive composition of claim 4, wherein the prepolymer is prepared by reacting an isocyanate compound having at least two isocyanate groups with the polyol compound of claim 1.

7. The adhesive composition according to claim 5, wherein the content of the polyol compound according to claim 1 is 40% by weight to 80% by weight, and the content of the second polyol is 20% by weight to 60% by weight, based on the total weight of the polyol component (B).

8. the weight ratio between the isocyanate component (A) and the polyol component (B) is 100:30 to 100:100; The adhesive composition of claim 4 , wherein the adhesive composition is solvent-containing or solvent-free.

9. 5. A method for preparing a laminated article using the adhesive composition of claim 4, comprising: providing a first substrate and a second substrate; mixing the (A) isocyanate component with the (B) polyol component to form a curable mixture; adhering the first substrate to the second substrate by using a layer of the curable mixture; and curing or allowing the curable mixture to harden.

10. 10. A laminated article comprising at least two substrates and an adhesive layer sandwiched therebetween, wherein the adhesive layer is formed by a reaction between the (A) isocyanate component and the (B) polyol component of the adhesive composition of claim 4.

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