Adhesive compositions

Abstract

Embodiments of the present disclosure are directed towards adhesive compositions including an isocyanate-reactive composition including a crystalline polymer, lignin, a solvent, and an isocyanate composition including an isocyanate.

Description

ADHESIVE COMPOSITIONSField of Disclosure

[0001] Embodiments of the present disclosure are directed towards adhesive compositions. Background

[0002] Laminating adhesives are used to bond different substrates together. These bonded substrates can be utilized for flexible packaging applications, for instance. The laminating adhesive can be applied to the surfaces of two polymeric substrate layers to form a bonding layer in between the two substrate layers. The laminating adhesive forms a bonding layer between the substrate layers to provide a bond between the two substrate layers to provide a laminate structure. There exists a continuing need for new and / or improved laminating adhesives and / or laminate structures.Summary

[0003] The present disclosure provides various embodiments, including the following. In some embodiments, the present disclosure relates to an adhesive composition including an isocyanate-reactive composition including: a crystalline polyol; lignin; a solvent; and an isocyanate composition including: an isocyanate.

[0004] The above summary of the present disclosure is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The description that follows more particularly exemplifies illustrative embodiments. In several places throughout the application, guidance is provided through lists of examples, which examples can be used in various combinations. In each instance, the recited list serves only as a representative group and should not be interpreted as an exclusive list.Detailed Description

[0005] Adhesive compositions are disclosed herein. The adhesive compositions disclosed herein can advantageously be utilized to provide an improved oxygen barrier property, i.e. , a reduced Oxygen Transmission Rate, and / or improved adhesion, i.e. a greater bond strength, as compared to other adhesive compositions. A reduced Oxygen Transmission Rate and / or a greater bond strength are desirable for a number of applications, such as flexible packaging applications used for packing food, cosmetics, and / or pharmaceuticals, for instance.

[0006] The adhesive compositions disclosed herein include an isocyanate-reactive composition and an isocyanate composition. One or more components of the isocyanatereactive composition may react with one or more components of the isocyanate compositionto make a laminate adhesive. In other words, the isocyanate-reactive composition and the isocyanate composition can be mixed and cured to make the laminate adhesive.

[0007] The adhesive compositions disclosed herein may be referred to as solvent-based compositions, in contrast to other compositions that are characterized as being either solventless compositions or water-based compositions.

[0008] Embodiments provide that the isocyanate-reactive composition includes a crystalline polyol, lignin, and a solvent.

[0009] As mentioned, the isocyanate-reactive composition includes a crystalline polyol. As used herein, "crystalline polyol" refers to a polyol having a melting transition (Tm) when measured using differential scanning calorimetry. As used herein, “polyol” refers to a molecule having an average of greater than 1.0 hydroxyl groups per molecule, e.g., an average hydroxyl functionality of greater than 1.0. The crystalline polyol can have a melting temperature of 35 °C to 60 °C.

[0010] The crystalline polyol can have an average hydroxyl functionality from 1.5 to 6. All individual values and subranges from 2 to 6 are included; for example, the crystalline polyol can have an average hydroxyl functionality from a lower limit of 1.5, 1.7, or 1.8 to an upper limit of 6, 5, or 4. In particular, the average hydroxyl functionality may range from 1.7 to 5, or from 1.8 to 4. One or more embodiments provide that the crystalline polyol has an average hydroxyl functionality of 2.

[0011] The crystalline polyol can have an average hydroxyl number from 50 to 300 mg KOH / g. All individual values and subranges from 50 to 300 mg KOH / g are included; for example, the crystalline polyol can have an average hydroxyl number from a lower limit of 50, 75, or 100 mg KOH / g to an upper limit of 300, 250, or 200. In particular, the average hydroxyl number may range from 75 to 250 mg KOH / g, or from 100 to 200 mg KOH / g. Average hydroxyl number can be determined according to ASTM D4274-21.

[0012] The crystalline polyol can have an acid number from 0.1 to 5 mg KOH / g. All individual values and subranges from 0.1 to 5 mg KOH / g are included; for example, the crystalline polyol can have an acid number from a lower limit of 0.1 , 0.2, or 0.3 mg KOH / g to an upper limit of 5, 3, or 2. In particular, the average acid number may range from 0.2 to 3 mg KOH / g, or from 0.3 to 2 mg KOH / g. Average acid number can be determined according to ASTM D664-18.

[0013] The crystalline polyol can have a number average molecular weight from 300 to 5,000 g / mol. All individual values and subranges from 300 to 5,000 g / mol are included; for example, the crystalline polyol can have a number average molecular weight from a lower limit of 300, 400, or 500 g / mol to an upper limit of 5,000, 4,000, 3,000, or 2,000 g / mol. In particular, thenumber average molecular weight may range from 300 to 4,000 mg g / mol, or from 400 to 3,000 g / mol, or from 500 to 2,000 g / mol. Number average molecular weight can be determined by GPC.

[0014] One or more embodiments provide that the crystalline polyol is selected from crystalline polyester polyols, crystalline polyester-polycarbonate polyols, crystalline polycarbonate polyols, or combinations thereof.

[0015] The crystalline polyol can be prepared using known equipment, reaction conditions, and reaction components. The crystalline polyol can be obtained commercially. A commercial example of the crystalline polyol is BESTER 86 from The Dow Chemical Company, among other commercial crystalline polyols.

[0016] One or more embodiments provide that the crystalline polyol can be made from a combination of a diol and a dicarboxylic acid. The diol can be a single linear aliphatic diol having from 2 to 10 carbon atoms. One or more embodiments provide that the diol is a COCO diol. In some embodiments, n-butanediol and / or n-hexanediol may be used. The dicarboxylic acid can be a linear dicarboxylic acid. The dicarboxylic acid can be selected from adipic acid, azelaic acid, sebacic acid, and combinations thereof, for instance. The crystalline polyol may be formed via the reaction of the diol and the dicarboxylic acid. For example, reaction of 1 ,6-hexanediol and adipic acid forms hexanediol adipate; reaction of 1 ,4-butanediol and adipic acid forms butanediol adipate; reaction of 1 ,6-hexanediol and azelaic acid forms hexanediol azelate; and so forth. Conditions for such reactions are known. As an example, making the crystalline polyol can include admixing the diol and the dicarboxylic acid and heating the admixture at a temperature from 100 °C to 250 °C to make the crystalline polyol.

[0017] As mentioned, the isocyanate-reactive composition includes lignin. Lignin is a known polymer. Lignin can be extracted from lignocellulosic materials. Lignin may be obtained by one or more known processes. For instance and without limitation, lignin may be obtained by the Kraft process, the soda pulping process, and / or the sulfite delignification of wood. Lignin may be obtained commercially. One or more embodiments provide that the lignin is technical lignin. As used herein, “technical lignin” refers to lignin obtained via a reclamation process, e.g., Kraft process, the soda pulping process, and / or the sulfite delignification of wood, in contrast to naturally occurring proto-lignin.

[0018] As mentioned, the isocyanate-reactive composition includes a solvent. The solvent may be one or more non-protonated solvents. Examples of the solvent include ethyl acetate, methylethylketone, dioxolane, tetrahydrofuran, acetone, dioxane, and combinations thereof.One or more embodiments provide that the solvent includes ethyl acetate and dioxane, e.g., 1 ,4-dioxane.

[0019] The crystalline polyol can be 15 to 74 weight percent (wt%) of the isocyanate-reactive composition based upon a total weight (100 wt%) of the isocyanate-reactive composition. All individual values and subranges from 15 to 74 wt% are included; for example, the crystalline polyol may be from a lower limit of 15, 20, or 25 wt% to an upper limit of 74, 70, or 65 wt% based upon a total weight of the isocyanate-reactive composition. In particular, the amount of the crystalline polyol in the isocyanate-reactive composition may range from 20 to 70 wt%, or from 25 to 65 wt%.

[0020] Lignin can be 3 to 25 wt% of the isocyanate-reactive composition based upon a total weight of the isocyanate-reactive composition. All individual values and subranges from 3 to 25 wt% are included; for example, lignin may be from a lower limit of 3, 5, or 8 wt% to an upper limit of 25, 20, 15, or 10 wt% based upon a total weight of the isocyanate-reactive composition. In particular, the amount of lignin in the isocyanate-reactive composition may range from 3 to 20 wt%, or from 5 to 15 wt%, or from 8 to 10 wt%.

[0021] One or more embodiments provide that the solvent can be 10 to 90 wt% of the isocyanate-reactive composition based upon a total weight of the crystalline polyol, the lignin, and the solvent. All individual values and subranges from 10 to 90 wt% are included; for example, the solvent may be from a lower limit of 10, 20, or 30 wt% to an upper limit of 90, 85, or 80 wt% based upon a total weight of the total weight of the crystalline polyol, the lignin, and the solvent. In particular, the amount of solvent in the isocyanate-reactive composition may range from 20 to 85 wt%, or from 30 to 80 wt%.

[0022] One or more embodiments provide that the isocyanate-reactive composition can have a solid content from 10 to 90 wt% based upon a total weight of the crystalline polyol, the lignin, and the solvent. All individual values and subranges from 10 to 90 wt% are included; for example, the isocyanate-reactive composition can have a solids content from a lower limit of 10, 20, or 30 wt% to an upper limit of 90, 80, or 70 wt% based upon a total weight of the crystalline polyol, the lignin, and the solvent. In particular, the solids content in the isocyanatereactive composition may range from 20 to 80 wt%, or from 30 to 70 wt%. The solids can be present due to lignin and the crystalline polyol.

[0023] Components of the isocyanate-reactive composition, e.g., the crystalline polyol, lignin, and the solvent, can be combined using known equipment and conditions. The crystalline polyol, lignin, and the solvent can be combined simultaneously or in portions. One or more embodiments provide that lignin and the solvent can be combined prior to addition of the crystalline polyol. One or more embodiments provide that the crystalline polyol and thesolvent can be combined prior to addition of lignin. One or more embodiments provide that the crystalline polyol and lignin can be combined prior to addition of the solvent.

[0024] As mentioned, the adhesive compositions disclosed herein include an isocyanate composition. The isocyanate composition includes one or more isocyanates. Isocyanates are known. The isocyanate can be an aliphatic polyisocyanate. The isocyanate can be a linear aliphatic diisocyanate. The isocyanate can be polymeric hexamethylene diisocyanate, i.e., a trimer isocyanurate of HDI, methylene diphenyl diisocyanate (MDI), dicyclohexylmethane 4,4'- diisocyanate (H12MDI), toluene diisocyanate (TDI) or combinations thereof. Examples of isocyanates include isocyanate terminated prepolymers, polyisocyanates, such as hexamethylene diisocyanate-based polyisocyanate, xylene diisocyanate-based polyisocyanates, isophorone diisocyanate-based polyisocyanates, methylene diphenyl diisocyanate-based polyisocyanates, toluene diisocyanate-based polyisocyanates, and combination thereof.

[0025] The isocyanate can be utilized to provide a mole ratio of isocyanate groups in the isocyanate composition to hydroxyl groups of crystalline polyol in the isocyanate-reactive composition from 1.1 to 3. Different mole ratios may be used for various applications.

[0026] In some embodiments, the adhesive compositions of the present disclosure can include one or more optional additives including but not limited to, for example, tackifiers, catalysts plasticizers, rheology modifiers, adhesion promoters, antioxidants, fillers, colorants, surfactants, and combinations of two or more thereof.

[0027] The amount of the optional components useful in the adhesive compositions can be, for example, from 0.01 wt % to 3 wt % in one embodiment, from 0.01 wt % to 2 wt % in another embodiment, or from 0.01 wt % to 1 wt % based upon a total weight of the adhesive composition.

[0028] The adhesive compositions disclosed herein can be made by combining, e.g. mixing, the isocyanate-reactive composition and the isocyanate composition. Known equipment and known conditions may be utilized for combining the isocyanate-reactive composition and the isocyanate composition to make the adhesive composition.

[0029] The isocyanate-reactive composition and the isocyanate composition can be combined near to a time of application for lamination purposes, e.g., prior to a lamination process. This combining can occur within approximately 1 minute or less of application to a polymeric material, or materials, to be laminated, for example. The isocyanate-reactive composition and the isocyanate composition can be combined such that the combining does not undesirably interfere with either application of the adhesive composition to the polymericfilm or films and / or attainment of the desired enhanced properties of the final laminate. Once combined, the mixture can be referred to as the adhesive composition.

[0030] One or more remedies provide that portions of the isocyanate-reactive composition and / or the isocyanate composition may be pre-reacted, e.g., to make an isocyanate-capped prepolymer, followed by reacting the remainder of the isocyanate-reactive composition and / or the isocyanate composition.

[0031] The adhesive compositions disclosed herein can be cured, e.g., to make a laminate by bonding different substrates together.

[0032] A laminate, e.g., a laminate structure, can be formed including a layer of cured of the adhesive compositions the present disclosure. Any number of layers can be used to form the laminate. In one preferred embodiment, the laminate is formed by the steps of: applying the adhesive composition to at least one of two substrate layers, e.g., the substrates can be a same material, e.g., polyethylene, or different materials, e.g., polyethylene and polypropylene; combining the substrates together such that the adhesive composition is disposed as a layer between surfaces of the two substrates; and then curing the adhesive composition to form a bonding layer between the two substrates. In general, each of the two substrates can include, for example, two separate polymer films. As used herein, a “film” is any layer structure that is 0.5 mm or less in one dimension of the layer structure; and is 1 cm or more in both of the other two dimensions of the layer structure. A “polymer film” is a film that is made of a polymer or mixture of polymers. The composition of a polymer film can be at least 80 percent by weight or more of one or more polymers.

[0033] Suitable substrates used to form the laminate include films such as paper, woven and nonwoven fabric, polymer films, metal-coated (metallized) polymer films, and combinations thereof. The substrates are layered to form a laminate, with an adhesive composition according to the present invention adhering one or more of the substrates together. One or more embodiments provide that polyethylene film and polypropylene film are utilized. One or more embodiments provide that only polyethylene film is utilized.

[0034] One or more embodiments provide that a multi-layer laminate, utilizing the adhesive composition of the present disclosure, includes: (A) at least a first layer; (B) at least a second layer; and (C) at least one layer of the adhesive composition disposed in between the first layer and the second layer; wherein the adhesive composition is cured to bond the first layer to the second layer.

[0035] One or more embodiments provide that the multi-layer laminate can be two or more film substrates or film layers combined together with the adhesive composition. In some embodiments, the laminate is a laminate film structure including a first film layer, a secondfilm layer, and a barrier adhesive layer disposed between the first film layer and the second film layer. For example, the multi-layer laminate can be made of three layers including the first film layer, the second film layer and a bonding layer comprising the cured adhesive composition disposed in between the first and second layers. The first film layer may be referred to as a primary film. The second film layer may be referred to as a secondary film.

[0036] A 3-layer laminate of the present disclosure can have a layered structure of A / B / A wherein A represents the first and second layers, e.g., substrates, being of the same material, e.g., polyethylene, and wherein B represents the bonding layer of cured adhesive composition. Although a 3-layer laminate is referenced herein, the present disclosure includes a multi-layer laminate with more than two film layers, provided that at least one layer of the multi-layer film laminate is the bonding layer of cured adhesive composition disclosed herein. As previously mentioned, the structure of the laminate can be A / B / A wherein both layers represented by A are made of the same polymer material, e.g. polyethylene; or the structure of the laminate can be A / B / C wherein C represents a film layer than is made of a different material than the layer of A. The laminate can be any combination of A, B, and C layers which are apparent to one skilled in the art of laminate making. One or more embodiments provide that for the A / B / A structure, both layers represented by A are made of the same polymer material and are prepared with a same film preparation process. One or more embodiments provide that for the A / B / A structure, both layers represented by A are made of the same polymer material, and are prepared with respectively different film preparation processes.

[0037] Layers of the laminate, as disclosed herein, can be made of one or more materials, including, for example, polyethylene, polypropylene, polyethylene terephthalate, polyamide, polystyrene, cycloolefin copolymer, polyvinyl chloride, styrene butadiene, and the like. One or more embodiments provide that the material(s) of the layers can be polypropylene, polyethylene, and combinations thereof. Examples of some of the commercial materials useful for laminates of the present disclosure include, for example, biaxial oriented polypropylene, available from Exxon Mobil; polyethylene films, available from The Dow Chemical Company; and polyethylene films, available from Berry Plastics

[0038] The thickness of the polymer film layers used in the laminate of the present disclosure can be from 10 pm to 200 pm. All individual values and subranges from 0 to 200 pm are included; for example, the polymer film layer can have a thickness from a lower limit of 10, 15, or 20 pm to an upper limit of 200, 150, or 125 pm. In particular, the thickness may range from 15 to 150 pm, or from 20 to 125 pm.

[0039] As aforementioned, the different layers of the laminate can be made of a same material, which may have an advantage of being more easily recyclable. In another embodiment, the different layers can be made of different materials.

[0040] A process for producing a laminate product as discussed herein can include: applying the adhesive composition of the present disclosure to at least a portion of the surface of a first layer and / or a second layer; contacting the first layer and the second layer such that the adhesive composition is disposed in between the first layer and the second layer; and curing the adhesive composition to form a laminate comprising the first layer bonded to the second layer via the cured adhesive.

[0041] One of the advantageous properties that may be exhibited by the laminate disclosed herein can include, for example, a laminate having an improved, i.e., a reduced, oxygen transmission rate (OTR), as compared to laminates made with other adhesive compositions. In some embodiments, e.g., when polyethylene is utilized as a primary film and a secondary film, the laminate can have an OTR not greater than 750 cubic centimeters of oxygen per [square meter-day] abbreviated as “ccO2 / m2 / day” and measured according to ASTM Method D3985. For instance, the laminate can have an OTR from 50 to 750 ccO2 / m2 / day. All individual values and subranges from 10 to 750 ccO2 / m2 / day are included; for example, the laminate can have an OTR from a lower limit of 10, 25, 50, 100, or 150 ccO2 / m2 / day to an upper limit of 750, 700, or 600 ccO2 / m2 / day. In particular, the OTR may range from 25 to 750, or from 50 to 750, or from 100 to 700, or from 150 to 600 ccO2 / m2 / day. An improved OTR is desirable for a number of applications.

[0042] One of the advantageous properties that may be exhibited by the laminate disclosed herein can include, for example, a laminate having an improved, i.e., greater, T-peel bond strength, as compared to laminates made with other adhesive compositions. In some embodiments, e.g., when polyethylene is utilized as a primary film and a secondary film, the laminate can have a 7-day T-peel bond strength greater than 250 g / inch and film tear (destruct bond) observed during adhesion testing. For instance, the laminate can have a 7- day T-peel bond strength from 250 to 2,500 g / inch. All individual values and subranges from 250 to 2,500 g / inch are included; for example, the laminate can have a 7-day T-peel bond strength from a lower limit of 250, 350, or 500 g / inch to an upper limit of 2,500, 2,000, or 1 ,500 g / inch. In particular, the 7-day T-peel bond strength may range from 350 to 2,000, or from 500 to 1 ,500 g / inch. T-peel bond strength, at 7 days and 14 days can be determined on 1-inch strips at a rate of 10 inch / min on a Thwing-Albert tensile tester with a 50 N loading cell. An improved 7-day T-peel bond strength is desirable for a number of applications.

[0043] The laminate prepared as described above can be used, for example, in flexible packaging applications; and in home and personal care applications. In one preferred embodiment, the laminate is used to make a multi-layer laminate structure product or article such as a package, pouch or container for packaging food. In a preferred embodiment, the laminate is made of two layers of polymeric film with an adhesive layer disposed in between the two film layers bonding the two polymer films together. The process of making an article such as a food packaging article can be carried out by those skilled in the art of food packaging manufacturing.

[0044] In addition, a laminate having an ABA structure can advantageously be a simple, readily manufacturable structure and can also beneficially be recyclable such that the packaging made from the laminate is environmentally friendly, as compared to some other packaging.EXAMPLES

[0045] In the Examples, various terms and designations for materials are used including, for instance, the following:

[0046] Crystalline Polyol (polyester polyol; BESTER 86; average hydroxyl functionality 2; average hydroxyl number 108 to 116 mg KOH / g; obtained from The Dow Chemical Company);

[0047] Lignin (Kraft pine lignin; INDULIN AT; obtained from Ingevity);

[0048] Solvent 1 (1 ,4-dioxane; obtained from Sigma Aldrich);

[0049] Solvent 2 (ethyl acetate; obtained from Sigma Aldrich);

[0050] Isocyanate Composition 1 (aliphatic polyisocyanate; MOR-FREE C-33; obtained from The Dow Chemical Company);

[0051] Isocyanate Composition 2 (isocyanate terminated prepolymer; MOR-FREE ELM 415 A; obtained from The Dow Chemical Company);

[0052] Polyol blend 1 (CR-89; obtained from The Dow Chemical Company);

[0053] Film 1 (BOPP; Biaxially Oriented Polypropylene Film, thickness 19 pm, obtained from Exxon Mobil);

[0054] Film 2 (MDO-PE; Polyethylene film stretched several times in a machine direction, thickness 25 pm; obtained from The Dow Chemical Company);

[0055] Film 3 (PE: GF-19, high slip low density polyethylene film, thickness 38 pm, obtained from Berry Plastics Corp.).

[0056] Polyol mixture 1 was made by combining Crystalline Polyol (33.3 wt%) and Solvent 1 as follows. The Crystalline Polyol was maintained in an oven (60 °C) for approximately 3.5 hours, then dispersed in Solvent 1 mixed on a roller to make Polyol Mixture 1.

[0057] Lignin mixture 1 was made by combining Lignin (33.3 wt%) and Solvent 1 as follows. Lignin was maintained in an oven (85 °C) for approximately 48 hours, then mixed with Solvent 1 utilizing a high speed FlackTek mixer (2,000 rpm) for 2 minutes, then again placed in an oven (50 °C) for approximately 3.5 hours and remixed with the FlackTek mixer until a homogenous mixture was observed.

[0058] Isocyanate-reactive composition 1 was made as follows. Polyol mixture 1 (75 wt%) and Lignin mixture 1 (25 wt%) were mixed utilizing a high speed FlackTek mixer (2,000 rpm) until a homogenous mixture was observed to make Isocyanate-reactive composition 1 .

[0059] Isocyanate-reactive compositions 2-3 were made as Isocyanate-reactive composition 1 with changes shown in Table 1.Table 1

[0060] Example 1 , an Adhesive Composition, was made as follows. Isocyanate-reactive composition 1 and Isocyanate 2 were mixed utilizing a high speed FlackTek mixer (2,000 rpm) until a homogenous mixture was observed to make Example 1 .

[0061] Example 2 and Comparative Examples A-C were made as Example 1 , with changes shown in Table 2.Table 2

[0062] Films 1-3 were corona treated before lamination.

[0063] Example 3, a laminate, was made as follows. Example 1 , an adhesive composition, was coated onto respective films using a Meyer bar to provide coat weights a range of 2-4Ib / ream. Lamination was conducted using a hot oil hand laminator with 150 °F nip temperature, 40 psi nip pressure, and at 27 in / min speed. The laminate samples were cured under a weight (2 lb) at approximately 20 °C for approximately 14 days.

[0064] Examples 4-6 and Comparative Examples D-l were made as Example 3, with changes shown in Table 3.Table 3

[0065] Oxygen transmission rates (OTR) were measured using a MOCON OXTRAN 2 / 21 according to ASTM method D3985.The OTR data (Avg-Transmission) is reported in the standard unit: ccO2 / m2 / day. The conditions used for testing to obtain OTR measurements were 23 °C and 50 % relative humidity (RH). Film 2 was determined to have an OTR of 3,144 ccO2 / m2 / day; Film 3 was determined to have an OTR of 4,930 ccO2 / m2 / day.

[0066] T-peel bond strength, at 7 days and 14 days, was measured on 1-inch strips at a rate of 10 inch / min on a Thwing-Albert tensile tester with a 50 N loading cell. Three strips were tested for each laminate and the high and mean strength were recorded along with the failure mode. In case of film tear, the average of high value was reported. In all other failure modes, the average of mean values was reported. Reported failure modes are: AF - Adhesive failure (adhesive on the primary film); AT - Adhesive transfer (adhesive on the secondary film); AS - Adhesive split (adhesive on both sides of the laminate, cohesive failure of the adhesive); FT - Film tear.

[0067] Results are reported in Tables 4-6. Table 4

[0068] The data of Table 4 show that each of Examples 5-6 have an improved, i.e., reduced, oxygen transmission rate as compared to each of Comparative Examples G-l. A relatively lower OTR is advantageous for a number of applications.Table 5Table 6

[0069] The data of Table 6 show that each of Examples 5-6 have an improved, i.e., greater, 7-day T-peel bond strength as compared to each of Comparative Examples G-l. A relatively greater 7-day T-peel bond strength is advantageous for a number of applications.

Claims

CLAIMS1. An adhesive composition comprising: an isocyanate-reactive composition comprising: a crystalline polyol; lignin; a solvent; and an isocyanate composition comprising: an isocyanate.

2. The adhesive composition of claim 1 , wherein the crystalline polyol is selected from crystalline polyester polyols, crystalline polyester-polycarbonate polyols, crystalline polycarbonate polyols, or combinations thereof.

3. The adhesive composition of any one of claims 1-2, wherein the crystalline polyol has an average hydroxyl functionality from 1 .5 to 6 and an average hydroxyl number from50 to 300 mg KOH / g.

4. The adhesive composition of any one of claims 1-3, wherein the lignin is 3 to 25 wt% of the isocyanate-reactive composition based upon a total weight of the isocyanate-reactive composition.

5. The adhesive composition of claim 4, wherein the crystalline polyol is 15 to 74 wt% of the isocyanate-reactive composition based upon the total weight of the isocyanatereactive composition.

6. A laminate comprising: a first substrate; a second substrate; and a cured layer of the adhesive composition of any one of claims 1 -5 between the first layer and the second layer; wherein the cured layer bonds the first layer to the second layer.

7. The laminate of claim 6, wherein the first substrate and the second substrate are different materials.

8. The laminate of claim 6, wherein the first substrate and the second substrate are a same material.

9. The laminate of claim 8, wherein the same material is polyethylene.

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