Two-component high-concentration bio-based polymer composition

Abstract

The teachings herein provide an adhesive comprising a curable adhesive formulation having an A-side having one or more epoxy resins and a B-side having an acidic phosphoric acid component, wherein the adhesive contains at least 30% by weight of a bio-based material.

Description

Technical Field

[0001] Claim of Priority This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 461,803, filed on April 25, 2023, which is hereby incorporated by reference in its entirety for all purposes.

[0002] The teachings herein relate to a composition having a first component and a second component. More specifically, the teachings herein relate to a two-component composition having one side containing an epoxide-functional composition and one side containing an acidic material composed of one or more bio-based resins.

Background Art

[0003] Products containing bio-based additives are alternatives for manufacturers seeking to reduce the use of petroleum-derived products. Petroleum-derived materials are becoming less attractive due to the uncertainty of future supplies of petroleum-derived chemicals and environmental concerns. Moreover, the continued use of petroleum-derived products may lead to further regulations regarding the manufacture and consumption of petroleum-derived products as their sources become further depleted. Thus, uncertainty of future supplies, environmental concerns, and regulations are driving the use of alternative environmentally friendly and renewable sources having comparable properties and costs.

[0004] Terms such as "bio-based," "biodegradable," and "recycled" are commonly used in similar contexts and can be confusingly similar. For the purposes of these instructions, "bio-based" will refer to organic, renewable carbon. Therefore, the percentage of bio-based content in resins, materials, etc., will refer to the percentage of organic carbon derived from renewable sources, i.e., plants. Renewable carbon is typically identified based on the carbon-14 content of a material, which is a weakly radioactive isotope not found in petroleum-derived materials. ASTM D6866 outlines the process by which renewable carbon content is measured.

[0005] Bio-based materials, such as bio-based resins, have attracted attention among researchers and manufacturers in recent years. Epichlorohydrin can be bio-based if synthesized from glycerol. The production of bio-based epichlorohydrin and glycidyl ethers from petroleum-derived alcohols / polyols, which are commonly used in industry, enables partially renewable resins. Bio-based materials can also be derived from cultivated renewable resources. Bio-based glycidyl ethers are commonly used due to their reactivity. Such glycidyl ethers are reaction products of epichlorohydrin and bio-based polyols, such as isosorbide. Bio-based polyols can also be produced from the reduction of bio-based polyacids. Another common type of bio-based resin used is glycidyl esters, which are typically produced from the reaction of bio-based acids and epichlorohydrin. Non-glycidyl ether epoxy resins have not attracted much attention from manufacturers due to their lower reactivity compared to glycidyl ether epoxy resins. Epoxylated bio-based resins, such as epoxylated linseed oil and epoxylated soybean oil, contain aliphatic disubstituted oxiranes that are not highly reactive with most known epoxy curative systems at ambient temperatures.

[0006] It is possible to produce several commonly used petroleum-derived materials from bio-based sources instead of petroleum-derived sources. One example is the production of alcohols from bio-based sources, commonly referred to as bio-alcohols. Non-limiting examples of alcohols that can be produced from bio-based sources include ethanol, butanol, and pentanol. Bio-alcohols can be reacted with epichlorohydrins to produce bio-based, epoxide-functionalized materials. As mentioned above, epichlorohydrins can also be obtained from bio-based sources, giving rise to the possibility of partially and completely bio-based epoxy resins. Bio-alcohols can also be reacted with phosphoric acid and phosphoric acid derivatives to produce partially and completely bio-based phosphate esters.

[0007] This instruction relates to a curing system that reacts very rapidly with aliphatic, disubstituted oxirane rings at ambient and even near-ambient temperatures. The use of highly reactive acidic compositions containing phosphoric acid and phosphoric acid derivatives enables ring-opening of such aliphatic, disubstituted oxirane rings. Using phosphoric acid as a curing agent in a two-component system with epoxy can result in a significant difference in viscosity. Furthermore, the use of phosphoric acid as a curing agent for epoxy resins presents challenges in applications due to its high reactivity and reaction speed. Therefore, phosphoric acid esters are required for practical two-component adhesives that are optionally foamed. A bio-based, environmentally friendly two-component product that is optionally foamed has been developed using bio-based materials on both sides. Any unsaturated oil, e.g., epoxidized oil resin derived from vegetable, nut, and seed oils, can be used on the resin side. Acid-phosphorous phosphate-modified bio-based materials and bio-based carboxylic acids have been used on the curing side. The applicants have developed an optionally foamed product with a renewable content exceeding 30% using bio-based materials on both sides of a two-component composition.

[0008] This disclosure relates to a method for preparing acidic phosphite compounds having a high renewable carbon content. Esters of phosphoric acid may be derived from bio-based mono / polyepoxys as well as bio-based alcohols / polyols. Such esters of phosphoric acid (e.g., phosphoric acid components) are formed by various reactions of phosphoric acid species, e.g., orthophosphoric acid, polyphosphoric acid, and P2O5, with the compounds described above. The functionality of the epoxidized bio-based compounds can be 1, 2, 3, or more. The average functionality of the acidic phosphite-containing compounds should be 2 or more in order to create a crosslinked network. [Overview of the project] [Means for solving the problem]

[0009] This disclosure relates to a two-component system. The two-component system can address at least some of the needs identified above.

[0010] The teachings herein pertain to curable adhesive formulations comprising one or more epoxy resins and one or more acidic phosphite species, wherein at least 30% by weight of the adhesive comprises a bio-based material.

[0011] The curable adhesive formulation may include an A-side having one or more epoxy resins and a B-side having an acidic phosphoric acid component, and the adhesive contains at least 30% by weight of a bio-based material.

[0012] The curable adhesive formulation may include an A-side having one or more epoxy resins and a B-side having an acidic phosphoric acid component, and the cured adhesive has an elongation of at least 10% as measured according to ASTM D638-10.

[0013] Bio-based materials may contain or be essentially derived from one or more epoxy resins and / or one or more acidic phosphite species or acidic phosphate components.

[0014] The bio-based carbon content of the bio-based material can be determined according to the ASTM D6866 testing method; preferably, the bio-based carbon content is at least 10%, more preferably at least 30%, even more preferably at least 50%, still more preferably at least 70%, and even more preferably at least 90%.

[0015] One or more epoxy resins may be bio-based, and / or one or more acidic phosphite species or acidic phosphate components may be bio-based.

[0016] (i) the biobase carbon content of one or more epoxy resins and / or (ii) one or more acidic phosphite species or acidic phosphate components may be determined according to the test method ASTM D6866; preferably, the biobase carbon content is at least 10%, more preferably at least 30%, even more preferably at least 50%, still more preferably at least 70%, and more preferably at least 90%.

[0017] One or more epoxy resins may be bio-based and may contain one or more epoxidized unsaturated oils.

[0018] One or more epoxy resins may be bio-based and may include one or more cashew nut shell liquid-based epoxy resins, linseed oil-based epoxy resins, castor oil-based epoxy resins, soybean oil-based epoxy resins, sorbitol-based epoxy resins, isosorbide-based epoxy resins, or any combination thereof.

[0019] One or more bio-based epoxy resins may be present in an amount of about 30% to about 90%, preferably about 40% to about 80%, more preferably about 50% to about 70%, by weight of the curable adhesive formulation or by weight of the A-side of the curable adhesive formulation.

[0020] One or more acidic phosphite species or acidic phosphate components may preferably be selected from the group consisting of ethanol-based phosphate esters, butanol-based phosphate esters, cashew nut shell liquid-based phosphate esters, castor oil-based phosphate esters, cellulose-based phosphate esters, tetrahydrofurfuryl alcohol (THFA)-based phosphate esters, ethylene glycol-based phosphate esters, isosorbide-based phosphate esters, or any combination thereof.

[0021] One or more acidic phosphite species or acidic phosphate components may be present in an amount of about 20% to about 90%, preferably about 40% to about 80%, more preferably about 50% to about 70%, by weight of the curable adhesive formulation or by weight of the B-side of the curable adhesive formulation.

[0022] The curing adhesive formulation may contain one or more additives.

[0023] The A-side of the curable adhesive formulation may contain one or more additives, preferably particulate or fibrous additives, including recycled rubber, recycled structural foaming epoxy powder, metal carbonates, minerals, reinforcing fibers, hydrophobic silica, or any combination thereof.

[0024] The B-side of the curable adhesive formulation may contain one or more additives, including minerals, reinforcing fibers, hydrophobic silica, glass microspheres, components stable in acidic media, or any combination thereof.

[0025] The curable adhesive formulation may contain an acid preferably selected from the group consisting of phosphoric acid, citric acid, acetic acid, and any combination thereof, preferably the acid being contained on the B-side of the curable adhesive formulation, and / or the acid being biobased.

[0026] One or more acidic phosphite species and acidic phosphate components may be the same.

[0027] The adhesive may undergo an expansion of at least 50% in volume.

[0028] The cured adhesive may have a peak stress of at least 0.02 MPa.

[0029] The adhesive and / or bio-based material may preferably have a bio-based content of at least 60% or even at least 80%, determined in accordance with the test method ASTM D6866.

[0030] The A-side may include at least 20 wt% or even at least 40 wt% of CNSL-based epoxy resin, linseed oil-based epoxy resin, or some combination thereof.

[0031] The B-side may include at least 40 wt% or even at least 80 wt% of CNSL-based epoxy resin, castor oil-based epoxy resin, or some combination thereof.

[0032] The B-side may include a THFA-based phosphate ester.

[0033] The B-side may include epoxidized soybean oil.

Mode for Carrying Out the Invention

[0034] The teachings herein, through the improved two-component systems described herein, satisfy one or more of the above-mentioned requirements. The explanations and examples presented herein are intended to inform those skilled in the art of the teachings, their principles, and their practical applications. Those skilled in the art can adapt and apply these teachings in their many forms so as to best suit the requirements of their particular use. Accordingly, the specific embodiments of the teachings shown herein are not intended to exhaust or limit these teachings. The scope of these teachings should therefore be determined without reference to the following description, but instead should be determined by reference to the appended claims, together with the entire scope of equivalents to which such claims are entitled. Disclosures of any papers and references, including patent applications and publications, are incorporated by reference for all purposes. Other combinations are also possible, as gathered from the following claims, and these too are thus incorporated by reference into this written specification.

[0035] This disclosure relates to a two-component bio-based system and a method for producing such a high-rate bio-based material having more than 50% renewable organic content, thereby reducing the use of petroleum-derived materials. Renewable sources as referred to herein mean natural sources that can replace themselves by natural processes in a short period of time.

[0036] As described herein, acidic phosphite components are components produced by the reaction of a particular acidic phosphite species with various materials. Non-limiting examples of acidic phosphite components include the phosphate esters described herein, and non-limiting examples of acidic phosphite species include orthophosphoric acid, polyphosphoric acid, and P2O5.

[0037] The bio-based epoxy resins used in the A-side of the teachings herein may contain glycidyl ethers. Such glycidyl ethers are formed by the reaction of a hydroxyl group of an alcohol / polyol with an epichlorohydrin. The alcohol / polyol may be derived from a bio-based source. The epichlorohydrin used, if produced from glycerol, may be bio-based, allowing for higher levels of bio-content. The oxirane functionality of bio-based epoxy can be 1 to 7 or even higher.

[0038] The bio-based epoxy resins used in side A of the teachings herein may contain glycidyl esters. Such glycidyl esters are formed by the reaction of a carboxyl group of an acidic compound with epichlorohydrin. The acidic compound may be derived from a bio-based source. The epichlorohydrin used, if produced from glycerol, can be bio-based, allowing for a higher level of bio-content.

[0039] The bio-based epoxy resins used in the A-side of the teachings herein may contain epoxidized unsaturated oils. The epoxidation reaction is carried out at the double bond carbon / carbon site by oxidation of natural oils with peroxide acid. Unsaturated oils may be derived from sources such as vegetables, nuts, seeds, and animals. Oil-based epoxidized linseed oil and epoxidized soybean oil, among others, may have different numbers of oxirane functionalities. Depending on their oxirane functionalities and molecular structure, these bio-based epoxidized epoxidized epoxidized densities and corresponding physical properties may result.

[0040] The first component may contain one or more bio-based epoxy resins, including one or more cashew nut shell liquid-based epoxy resins, linseed oil-based epoxy resins, castor oil-based epoxy resins, soybean oil-based epoxy resins, sorbitol-based epoxy resins, isosorbide-based epoxy resins, or any combination thereof. The one or more bio-based epoxy resins may be present in an amount of about 30% to about 90% by weight of the first component.

[0041] The number of commercially available bio-based epoxies is currently limited compared to petroleum-derived epoxies. This can make it difficult for formulaters to match the properties of their petroleum-derived two-component epoxy systems. Acidic phosphite compounds, such as phosphoric acid and its derivatives, bio-based phosphate esters, and petroleum-derived phosphate esters, are highly reactive with bio-based and petroleum-derived epoxies. Therefore, properties can be modified using limited amounts of petroleum-derived epoxy, petroleum-derived phosphate ester, or a combination thereof. This would reduce the bio-based content, although the bio-based content can still be high by using bio-based materials on both the A-side and B-side.

[0042] The first component may contain one or more phenoxy-epoxy solutions, carboxyl-terminated butadiene acrylonitrile (CTBN)-added epoxy resins, reactive diluents, bisphenol A-based resins, bisphenol F-based resins, novolac resins, any number of currently available epoxide-functional materials not indicated herein, or any combination thereof, one or more of which may be partially bio-based or petroleum-derived epoxy resins. One or more additional epoxy resins may be present in an amount of about 1% to 40% by weight of the first component. More desirable physical properties can be achieved by using one or more additional epoxy resins.

[0043] The first component may contain one or more additives. These additives may include, but are not limited to, particulate or fibrous additives, including recycled rubber, recycled structural foamed epoxy powder, metal carbonates, minerals, reinforcing fibers, hydrophobic silica, or any combination thereof.

[0044] The metal carbonate may include zinc carbonate, calcium carbonate, sodium bicarbonate, any number of commercially available metals and / or bicarbonates not indicated herein, or any combination thereof. The calcium carbonate may include heavy calcium carbonate, precipitated calcium carbonate, or any combination thereof. The calcium carbonate may include ultra-fine calcium carbonate, fine calcium carbonate, medium-fine calcium carbonate, medium calcium carbonate, coarse calcium carbonate, or any combination thereof. The two-component system can be foamed to an increased volume of about 50% to 1000% after mixing the first and second components.

[0045] The most well-known epoxy curing systems are unreactive or slowly reactive with aliphatic disubstituted oxiranes at ambient temperature. Aliphatic disubstituted oxiranes, formed by peroxy acid epoxidation reactions, include many low-cost and epoxidized bio-based triglycerides, but are between slowly and unreactive with common epoxy curing agents at room temperature. Oxirane groups are unreactive or weakly reactive with amine-derived curing agents. Epoxidized bio-based oils can be cured and crosslinked with carboxylic acids if the average oxiran functionality is greater than 2. The reaction between oxiran groups and carboxylic acid groups is also very slow compared to the reaction rate between oxiran groups and acidic phosphite compounds. This disclosure relates to an acidic phosphite bio-based ester curing agent that reacts very rapidly with oxiran groups.

[0046] The second component may contain one or more acids. The one or more acids may contain at least one or more phosphate esters derived from a bio-based epoxy or polyol. The one or more phosphate esters derived from a bio-based epoxy or polyol may include ethanol-based phosphate esters, butanol-based phosphate esters, cashew nut shell liquid-based phosphate esters, castor oil-based phosphate esters, cellulose-based phosphate esters, tetrahydrofurfuryl alcohol (THFA)-based phosphate esters, ethylene glycol-based phosphate esters, isosorbide-based phosphate esters, or any combination thereof. The phosphate esters may be present in the second component in an amount of about 20% to 90% by weight of the second component.

[0047] The second component may contain at least one or more additives. The one or more additives may include one or more minerals, reinforcing fibers, hydrophobic silica, core-shell particulate polymers, glass microspheres, or any combination thereof.

[0048] The two-component system may contain a total renewable carbon content of more than 30%, more preferably more than 60%, and even more preferably more than 90%.

[0049] The two-component system may also be thermosetting.

[0050] Two-component systems can cure at temperatures of approximately 0°C to 60°C. Two-component systems can also cure at room temperature (i.e., approximately 20°C to 25°C).

[0051] U.S. Patent No. 10,550,220 illustrates the use of phosphoric acid and phosphate esters for cure-in-place compositions. Such compositions are typically used in a wide range of room-temperature activated systems, e.g., for rigid structural foams, cavity fillers, gaskets, and sealants. The advantages of such compositions may include the ability to adhere to various substrates, low volatile organic compound (VOC) content, insensitivity to preparation temperature, insensitivity to precise mixing ratios of two-component systems, the ability to adjust physical and / or mechanical properties, or any combination thereof. The focus of this teaching is to extend the range of these systems to include high-concentration bio-based compositions with similar chemistry and properties to those in the applications described above.

[0052] Side A may contain one or more bio-based epoxy resins. The bio-based epoxy resins may include, but are not limited to, cashew nut shell liquid-based epoxy resins, linseed oil-based epoxy resins, castor oil-based epoxy resins, soybean oil-based epoxy resins, sorbitol-based epoxy resins, isosorbide-based resins, any other epoxy derived from a bio-based source, or any combination thereof.

[0053] Side A may comprise one or more bio-based monofunctional aromatic and / or aliphatic epoxy resins. The bio-based monofunctional aromatic epoxy resin may have an epoxy equivalent of about 425 g / eq to 575 g / eq according to ASTM D1652-97. The monofunctional aromatic epoxy resin may have a viscosity measured at 25°C of about 40 cP to about 70 cP according to ASTM D2196. The monofunctional aliphatic epoxy resin may comprise epoxidized cardanol. A non-limiting example of a suitable monofunctional aromatic epoxy resin is Cardolite® NC-513, commercially available from Cardolite Corporation.

[0054] Side A may comprise one or more bio-based polyfunctional aromatic and / or aliphatic epoxy resins. These bio-based polyfunctional aromatic and / or aliphatic epoxy resins can increase the crosslinking density of the reaction product, improve the mechanical properties of the reaction product, improve the chemical resistance of the reaction product, reduce the viscosity of the two-component system and / or mixed composition, improve the cell structure quality of the foamed reaction product, or any combination thereof. The functionality of the bio-based polyfunctional aromatic and / or aliphatic resin may be about 2 or more, 3 or more, or even 4 or more. The functionality of the polyfunctional aromatic and / or aliphatic resin may be about 8 or less, 7 or less, or even 6 or less.

[0055] Side A may contain one or more metal carbonates if foaming is desired. When the two-component system includes a metal carbonate in Side A, the effective functionality of Side B may be partially reduced in the mixed composition. This may be due to the reaction between the metal carbonate in Side A and the acid in Side B to produce foaming. Side A may contain components with increased functionality to compensate for the reduced functionality of Side B as a result of the metal carbonate reaction. Side A can be formulated with increased functionality by using a reactive component with higher functionality than Side A, such as an aliphatic polyfunctional epoxy resin.

[0056] Suitable examples of bio-based polyfunctional resins include, but are not limited to, cashew nut shell liquid-based epoxy resins, linseed oil-based epoxy resins, castor oil-based epoxy resins, sorbitol-based epoxy resins, isosorbide-based epoxy resins, or any combination thereof.

[0057] The bio-based bifunctional aromatic epoxy resin may have an epoxy equivalent of approximately 350 g / eq to 500 g / eq. The bifunctional aromatic epoxy resin may have a viscosity measured at 25°C with approximately 25,000 cP. The bifunctional aromatic epoxy resin may contain epoxidized cardanol. A non-limiting example of a suitable bifunctional aromatic epoxy resin is Cardolite® NC-514, commercially available from Cardolite Corporation.

[0058] The bio-based polyfunctional aromatic epoxy resin may have an epoxy equivalent of approximately 550 g / eq to 850 g / eq according to ASTM D1652-97. The polyfunctional aromatic epoxy resin may have a viscosity measured at 25°C at approximately 20,000 cP to approximately 50,000 cP according to ASTM D2196. The polyfunctional aromatic epoxy resin may contain epoxidized cardanol. A non-limiting example of a suitable polyfunctional aromatic epoxy resin is Cardolite® NC-547, commercially available from Cardolite Corporation.

[0059] The bio-based polyfunctional aliphatic epoxy resin may have an epoxy equivalent of approximately 175 g / eq. The polyfunctional aliphatic epoxy resin may have a viscosity measured at approximately 750 cP at 25°C. The polyfunctional aliphatic epoxy resin may contain epoxidized linseed oil. A non-limiting example of a suitable polyfunctional aliphatic epoxy resin is Epoxol® 9-5, commercially available from ACS Technical Products.

[0060] The bio-based polyfunctional aliphatic epoxy resin may have an epoxy equivalent of approximately 550 g / eq to 650 g / eq. The polyfunctional aliphatic epoxy resin may have a viscosity measured at 25°C at approximately 300 cP to approximately 500 cP. The polyfunctional aliphatic epoxy resin may contain castor oil glycidyl ether. A non-limiting example of a suitable polyfunctional aliphatic epoxy resin is KF EPIOL-PE 412, commercially available from Kukdo Chemical Co., Ltd.

[0061] The bio-based polyfunctional aliphatic epoxy resin may have an epoxy equivalent of approximately 200 g / eq to 300 g / eq. The polyfunctional aliphatic epoxy resin may have a viscosity measured at 25°C of approximately 300 cP to 400 cP. The polyfunctional aliphatic epoxy resin may contain epoxidized soybean oil. A non-limiting example of a suitable polyfunctional aliphatic epoxy resin is PLASTHALL® ESO, commercially available from Hallstar.

[0062] The bio-based polyfunctional aliphatic epoxy resin may have an epoxy equivalent of approximately 175 g / eq to 190 g / eq. The polyfunctional aliphatic epoxy resin may have a viscosity measured at 25°C at approximately 4,000 cP to approximately 6,000 cP. The polyfunctional aliphatic epoxy resin may contain sorbitol polyglycidyl ether. A non-limiting example of a suitable polyfunctional aliphatic epoxy resin is KF EPIOL-PE 510, commercially available from Kukdo Chemical Co., Ltd.

[0063] The bio-based polyfunctional aliphatic epoxy resin may have an epoxy equivalent of approximately 170 g / eq to 190 g / eq according to KD-AS-001. The polyfunctional aliphatic epoxy resin may have a viscosity measured at 25°C of approximately 4,000 cP to approximately 8,000 cP according to KD-AS-005. The polyfunctional aliphatic epoxy resin may contain isosorbide diglycidyl ether. A non-limiting example of a suitable polyfunctional aliphatic epoxy resin is KUKDO EPOXY KDBM-1040, which is commercially available from Kukdo Chemical Co., Ltd.

[0064] Bio-based polyfunctional aliphatic epoxy resins may include epoxy resins to which dimer acids have been added. The epoxy resins may be partially defunctionalized as a result of esterification reactions with dimer acids. A non-limiting example of a suitable dimer acid is Pripol® 1017.

[0065] A-side may contain one or more additional epoxy resins, which may be bio-based or petroleum-derived. The reason for using petroleum-derived epoxy resins is to improve the desired properties. The additional epoxy resins may include phenoxy-epoxy solutions, carboxyl-terminated butadiene acrylonitrile (CTBN)-added epoxy resins, reactive diluents, bisphenol A-based resins, bisphenol F-based resins, or any combination thereof. The additional epoxy resins may be present in A-side in an amount of about 1% to 40% or more by weight of A-side.

[0066] The two-component system may contain one or more epoxy / elastomer adducts. These adducts may be included to impart a plasticizing effect to the two-component system, or to induce phase separation of the two-component system, and / or to modify the structural properties of the two-component system, such as strength, strain-to-failure (fracture strain, fracture strain), fracture toughness (G1c), peel, adhesive durability, uncured material integrity (i.e., low likelihood of sticking, breaking, or deforming before use), and stiffness. Carboxylate-terminated butadiene acrylonitrile may be particularly useful for inducing adhesion to contaminated surfaces. Contaminated surfaces may contain oils, such as stamping lubricants typical of the automotive industry.

[0067] The elastomer in the adduct can be selected from polysulfide, polybutadiene, polyisoprene, polyisobutylene, isoprene-butadiene copolymer, neoprene, acrylic, natural rubber, carboxyl-terminated butadiene acrylonitrile, polysiloxane, polyester, urethane prepolymer, nitrile rubber (e.g., butylnitrile, e.g., carboxyl-terminated butylnitrile), butyl rubber, polysulfide elastomer, acrylic elastomer, acrylonitrile elastomer, silicone rubber, polyester rubber, diisocyanate-linked condensed elastomer, styrene-butadiene rubber, ethylene-propylenediene rubber, chlorosulfonated polyethylene, fluorinated hydrocarbons, or any combination thereof. The epoxy / elastomer adduct may also contain carboxyl-terminated polymers (e.g., added carboxyl-terminated polymer, added carboxyl-terminated butylnitrile). The epoxy / elastomer adduct may be a dicarboxylic acid. Suitable elastomer compounds for the adduct, although not required, may be thermosetting elastomers.

[0068] The first component may contain one or more non-liquid additives. One or more additives may include recycled rubber, recycled structural foaming epoxy powder, one or more metal carbonates, minerals, reinforcing fibers, hydrophobic silica, or any combination thereof.

[0069] The first component may contain recycled rubber particles for the purpose of including a recycled material content in the composition. The recycled rubber may include one or more types of micronized rubber powders. The micronized rubber powders may contain at least 40% recycled rubber. Recycled rubber typically uses end-of-life rubber that has been tested for health and safety, in contrast to newly produced rubber which contributes to environmental pollution and the consumption of petroleum-derived raw materials. Recycled rubber itself is not bio-based, but it can replace other petroleum-derived fillers and contribute to the overall environmental consideration of the product.

[0070] The first component may contain recycled structural foaming epoxy powder. The recycled structural foaming epoxy powder may contain non-solid rubber adducts having structural foam. The recycled structural foaming epoxy powder may contain materials that have exceeded their shelf life and are no longer considered useful for their original purpose. The recycled structural foam is not bio-based but can replace other petroleum-derived fillers and contribute to the overall environmental consideration of the product. A non-limiting example of a suitable structural foam is L-5905, commercially available from L&L Products.

[0071] A two-component system can effervesce due to the presence of one or more metal carbonates in the two-component system. The metal carbonates can react with an acid. The metal carbonates may be provided on side A. The acid may be provided on side B. The metal carbonates may include zinc carbonate, calcium carbonate, sodium bicarbonate, any number of commercially available metal carbonates and / or bicarbonates not indicated herein, or any combination thereof.

[0072] Calcium carbonate can be provided as a combination of fine and moderately fine-sized calcium carbonate. Fine calcium carbonate can provide a uniform and fine cellular structure. The combination of fine and moderately fine-sized calcium carbonate can provide a balance between foaming and curing, and thus structural integrity of the foam.

[0073] The reaction product may have a volume expansion of approximately 50% to 1000%.

[0074] Foaming can be initiated before the complete reaction of the epoxide functional monomers and oligomers. The foaming time of the mixed composition may be approximately 30 seconds or longer, 1 minute or longer, 5 minutes or longer, or even 10 minutes or longer. The foaming time of the mixed composition may be approximately 2 hours or less, 1 hour or less, or even 30 minutes or less. The foaming time may be the time frame in which the two-component system foams actively.

[0075] Calcium carbonate may include ultrafine particle size calcium carbonate. The ultrafine particle size may be about 1 to 3 microns, or more preferably about 2 microns. A non-limiting example of a suitable ultrafine calcium carbonate is Hubercarb® Q2, which is commercially available from Huber Engineered Materials.

[0076] The calcium carbonate may contain moderately fine-grained calcium carbonate. The moderately fine-grained particles may be about 20 to 24 microns, or more preferably about 22 microns. A non-limiting example of a suitable moderately fine-grained calcium carbonate is Hubercarb® Q200, a moderately fine-grained calcium carbonate commercially available from Huber Engineered Materials.

[0077] The calcium carbonate may include moderately fine-grained calcium carbonate. The moderately fine-grained particles may be about 10 to 16 microns, or more preferably about 13 microns. A non-limiting example of a suitable ultrafine-grained calcium carbonate is Hubercarb® Q325, which is commercially available from Huber Engineered Materials.

[0078] The calcium carbonate may contain calcium carbonate with a coarse particle size. The coarse particle size may be approximately 200 to 800 microns, 300 to 700 microns, or even 400 to 600 microns. A non-limiting example of a suitable ultrafine calcium carbonate is Hubercarb® Q40-200, which is commercially available from Huber Engineered Materials.

[0079] The minerals may include one or more silicate minerals. The silicate minerals may include one or more inosilicates. The inosilicates may include wollastonite. Wollastonite can improve mechanical strength, durability, adhesion, moisture resistance, impact resistance, or any combination thereof. The external shape of the individual crystals or crystal clusters of one or more minerals may be acicular. The acicular structure of minerals having an aspect ratio in the range of 9 to 20 can help improve the mechanical strength and durability of the reaction product. Wollastonite may contain a small percentage of metal carbonate impurities, which can consequently contribute to foaming. Non-limiting examples of suitable wollastonite include NYGLOS® 12 and NYGLOS® 8, commercially available from NYCO Minerals Inc., and Vansil® HR2000, commercially available from Vanderbilt Minerals, LLC.

[0080] Fumed silica containing hydrophobic silica can be used as a thickener or thixotrope for products. The thixotropic properties of hydrophobic silica allow for increased viscosity of materials without increasing material distribution difficulties. Hydrophobic silica can also be used as a settling inhibitor to improve the shelf life of materials. Non-limiting examples of suitable hydrophobic silica include AEROSIL® R 202, commercially available from Evonik Corporation, and CAB-O-SIL® TS-530 and TS-720, commercially available from Cabot Corporation.

[0081] Organic affinity phyllosilicates can be used as a substitute for hydrophobic silica. A suitable example of an organic affinity phyllosilicate is Garamite-1958, which is commercially available from BYK-Chemie GmbH.

[0082] The B-side may contain one or more bio-based acids, acid anhydrides, epoxy resin / phosphate reaction products, reactive diluents, additives, or any combination thereof. Reactive diluents and / or additives may be as needed. The B-side may essentially consist of one or more bio-based acids.

[0083] The B-side may contain one or more acids. The acid may be a liquid at room temperature. Room temperature, as referred to herein, can mean a temperature of about 20°C to 25°C. The acid may contain a phosphate ester, phosphoric acid, citric acid, acetic acid, other acidic phosphite compounds, any acid stable with phosphoric acid or a phosphate ester, or any combination thereof. Other acidic phosphite compounds can be represented by the following formula, where X- and Y- can independently represent -OH, -OR, or any covalent bond. R can represent any covalent bond, preferably an aliphatic, alicyclic, or aromatic bond.

[0084] [ka]

[0085] Other non-limiting examples of suitable phosphite compounds include polyphosphates and / or phosphites.

[0086] The acid may contain any suitable acid that is stable with phosphoric acid or a phosphoric acid ester, and / or will not affect shelf stability when mixed with phosphoric acid or a phosphoric acid ester. The acid may contain at least a phosphoric acid ester and optionally any acid that is stable with phosphoric acid, citric acid, acetic acid, a carboxylic acid, another acidic phosphite compound, phosphoric acid or a phosphoric acid ester, or any combination thereof.

[0087] Acids can contribute to the effervescence of two-component systems. That is, acids can react with metal carbonates (e.g., calcium carbonate) present on the A-side.

[0088] The working time of the mixed composition can be adjusted by the choice of acid. Using phosphate esters instead of phosphoric acid can delay the curing reaction due to their higher molecular weight, lower functionality, or any combination thereof. The working time can be adjusted by selecting the functionality and molecular weight of the phosphate ester.

[0089] The B-side may contain one or more phosphate esters, phosphate ester precursors, or both. The B-side may contain one or more phosphate ester precursors that can be combined with phosphate before being combined with the A-side.

[0090] The B-side may contain one or more bio-based phosphate esters. The bio-based phosphate esters may be reaction products of phosphoric acid and mono-epoxides under conditions known in the art. This process is described in U.S. Patent No. 10,550,220.

[0091] Bio-based phosphate esters may include phosphate esters derived from cashew nut shell sap. Cashew nut shell sap can be epoxidized. Epoxidized cashew nut shell sap may be the reaction product of one or more components of cashew nut shell sap and epichlorohydrin. One or more components of cashew nut shell sap may include anacardic acid, cardanol, cardol, or any combination thereof, having an aliphatic C10-C20 moiety. The aliphatic C10-C20 moiety may be saturated or unsaturated. The aliphatic C10-C20 moiety may be hydrophobic. The phosphate ester may also be the reaction product of epoxidized cashew nut shell sap and phosphate, as shown below, where n is the number of double bonds in the aliphatic chain:

[0092] [ka]

[0093] Cardanol-based cashew nut shell liquids have been illustrated above, but other components of cashew nut shell liquids are intended by this disclosure. A non-limiting example of a suitable epoxidized cashew nut shell liquid is Cardolite® LITE 2513HP, which is commercially available from Cardolite Corporation, Monmouth Junction, NJ.

[0094] Bio-based phosphate esters can be produced from bio-based alcohols using methods known in the art. A similar process is illustrated in "Commercial Synthesis of Monoalkyl Phosphates" (1).

[0095] Bio-based phosphate esters may include phosphate esters derived from castor oil (1). A non-limiting example of a suitable castor oil is the castor oil USP commercially available from Acme-Hardesty Co.

[0096] Bio-based phosphate esters may include phosphate esters derived from THFA (1). A non-limiting example of a suitable THFA is the 99% THFA commercially available from Sigma-Aldrich.

[0097] Bio-based phosphate esters may include phosphate esters derived from cellulose (1). A non-limiting example of a suitable cellulosic material is the finely ground dwarf sedge commercially available from WyoComposites, LLC.

[0098] Bio-based phosphate esters may include phosphate esters derived from dimer ols (1). A non-limiting example of a suitable dimer ol is Pripol® 2030, commercially available from Croda International, PLC.

[0099] Phosphate esters can be produced by the reaction of a phosphate ester precursor with phosphate in a range of stoichiometric ratios. One or more phosphate esters can be produced by the reaction of a phosphate ester precursor with phosphate in a ratio of about 0.6:1 to 1:0.6, more preferably about 0.7:1 to 1:0.7, or even more preferably about 0.8:1 to 1:0.8. The phosphate ester may be present in an amount of about 40% to 90% by weight of the B-side.

[0100] The B-side may contain additional phosphoric acid. The additional phosphoric acid may include orthophosphoric acid, polyphosphoric acid, or both. The additional phosphoric acid can increase the crosslink density and reduce the open time. The reaction rate of the pre-reacted phosphate ester can be increased by the addition of additional phosphoric acid to the B-side. The additional phosphoric acid can increase the foaming speed and total volume of the mixed composition.

[0101] Phosphoric acid, citric acid, acetic acid, phytic acid, other acidic phosphite compounds, any acid stable with phosphoric acid or phosphate esters, or any combination thereof may be present in the B-side in amounts of approximately 30% to 100% by weight of the B-side.

[0102] Side B may contain one or more additives. One or more additives may include minerals, reinforcing fibers, hydrophobic silica, glass microspheres, any component stable in acidic media not indicated herein, or any combination thereof.

[0103] Glass microspheres can be fabricated from molten borosilicate glass. Glass microspheres may be hollow. They may have a bulk density of about 0.1 g / cc to 0.3 g / cc, more preferably 0.2 g / cc to 0.25 g / cc, or even more preferably about 0.22 g / cc. A non-limiting example of a suitable glass microsphere may be Sphericel® 34P30, commercially available from Potters Industries Inc.

[0104] A table of organic materials used on either side A or side B can be found in Table 1 below. The calculation of the bio-based content is expressed in Equation 1 below. The calculation of the weight percentage of carbon is expressed in Equation 2 below.

[0105] [Table 1]

[0106] Equation 1.

number

[0107] Equation 2.

number

[0108] The two-component composition can be mixed in a volume ratio of A-side to B-side. The volume ratio of A-side to B-side may be approximately 2:1. [Example]

[0109] Tables 2 and 3 below present the two-component formulations of this disclosure. The volume ratio of A-side to B-side was 2:1. These non-limiting bio-based formulations are flexible and pliable foaming compositions.

[0110] [Table 2]

[0111] [Table 3]

[0112] Table 4 shows the results of physical tests for the formulations in Tables 2 and 3. The foaming percentage was obtained by distributing 100 g of material into a 400 mL beaker and recording the starting / final volumes. Tension tests were performed using a 120 mm long dogbone with a 10 mm width in the gauge length section. The dogbone was 3 mm thick and tested according to ASTM D638-10. Compression tests were performed using a 30 mm × 60 mm cylinder according to ASTM D695. Table 4 also includes estimates of the bio-content percentage, expressed as the percentage of carbon content in the renewable compounds and expressed in Equation 1.

[0113] [Table 4]

[0114] Table 5 shows two-component formulations relating to this disclosure. As previously mentioned, the addition of petroleum-derived epoxy resins and / or phosphate esters can improve desired properties. Compared with Tables 2 and 3, the formulations in Table 5 use a phenoxy-epoxy solution on the A-side, a CTBN-added epoxy resin on the A-side, an ethylhexylglycerin-based phosphate ester on the B-side, or a combination of these petroleum-derived materials. These additions increased the tensile elongation of the material.

[0115] [Table 5]

[0116] Table 6 shows the tensile test results and estimated bio-content of the formulations in Table 5. These results are compared to sample 32 in Table 2, which does not contain additional petroleum-derived epoxy resin or phosphate ester.

[0117] [Table 6]

[0118] Table 7 shows the two-component formulations relating to this disclosure. As previously mentioned, the adhesives are foamy as needed. The formulations in Table 7 include formulations with and without any of the previously mentioned calcium carbonate particles. Samples 70 and 72 do not contain calcium carbonate particles. As a result, samples 70 and 72 are non-foaming.

[0119] [Table 7]

[0120] Table 8 shows the results of lap shear testing and estimated bio-content for the formulations in Table 7. Lap shear testing was performed on 25.4 mm × 101.6 mm, 2 mm thick 6022 aluminum coupons with a 0.5 mm bondline and a 12.7 mm overlap. Testing was performed according to ASTM D1002-10.

[0121] [Table 8]

[0122] When used herein, unless otherwise stated, this instruction assumes that any member of a genus (list) may be excluded from that genus; and / or any member of a Markush grouping may be excluded from that grouping.

[0123] Unless otherwise stated, any numerical values ​​listed herein include all values ​​from the lower to the upper range in increments of one unit, provided that there is at least a two-unit separation between any lower and any higher value. For example, if the values ​​of the quantity, properties, or process variables such as temperature, pressure, time, etc., are described as being between 1 and 90, preferably 20 and 80, and more preferably 30 and 70, then intermediate range values ​​such as (e.g., 15 and 85, 22 and 68, 43 and 51, 30 and 32, etc.) are intended to be within the teachings of this specification. Similarly, individual intermediate values ​​are also within the teachings of this specification. For values ​​less than 1, one unit is considered to be 0.0001, 0.001, 0.01, or 0.1, as appropriate. These are merely examples of what is specifically intended, and it should be considered that all possible combinations of numerical values ​​between the listed lowest and highest values ​​are explicitly described in this application in a similar manner. As can be seen above, the teaching of quantities expressed as “parts by weight” in this specification also intends to include the same range expressed in units of weight percentage. Therefore, the expression in units of “at least “x” parts by weight of the resulting composition” also intends to include the teaching of the same range of enumerated quantities of “x” in weight percentage of the resulting composition.

[0124] Unless otherwise stated, any range includes both endpoints and all numbers between the endpoints. The use of “about” or “approximately” in relation to a range applies to both ends of the range. Thus, “about 20–30” is intended to encompass “about 20–about 30,” including at least the specified endpoint. Unless otherwise stated, a teaching using the term “about” or “approximately” in combination with a numerical quantity includes the teaching of an approximation of the enumerated quantity, along with the enumerated quantity itself. For example, the teaching of “about 100” includes the teaching of 100.

[0125] All disclosures of papers and references, including patent applications and publications, are incorporated herein by reference for all purposes. The term “essentially consisting of” used to describe a combination includes the identified element, component, constituent or step and other elements, components, constituent or steps that do not substantially affect the basic and novel features of the combination. The use of the terms “comprising” or “including” used herein to describe a combination of elements, components, constituent or steps also intends to include embodiments consisting of or essentially consisting of such element, component, constituent or step.

[0126] Multiple elements, components, constituents, or steps may be provided by a single integrated element, component, constituent, or step. Alternatively, a single integrated element, component, constituent, or step may be divided into multiple separate elements, components, constituents, or steps. The disclosure of “a” or “one” to describe a certain element, component, constituent, or step is not intended to exclude additional elements, components, constituents, or steps.

[0127] As used herein, the terms “comprising” and “including” can be used interchangeably. This is preferably applied with respect to the appended claims.

[0128] As used herein, “aliphatic” preferably means a linear or branched hydrocarbon free radical containing up to 24 carbon atoms, wherein the saturation between any two carbon atoms is a single, double, or triple bond. Aliphatic groups preferably contain 1 to about 24 carbon atoms, more typically 1 to about 12 carbon atoms, and more preferably 1 to about 6 carbon atoms.

[0129] As used herein, “alicyclic” preferably means a saturated or unsaturated non-aromatic hydrocarbon moiety having 1 to 3 rings, each ring having 3 to 8 (preferably 3 to 6) carbon atoms.

[0130] As used herein, “aromatic” preferably means a monocyclic or polycyclic carbocyclic free radical having one or more aromatic rings. Examples of aryl groups include, but are not limited to, phenyl and naphthyl.

[0131] It is understood that the above description is intended to be illustrative rather than restrictive. Many applications, along with many embodiments, will become apparent to those skilled in the art after reading the above description, in addition to the examples provided. The scope of the invention should therefore be determined without reference to the above description, but instead should be determined by reference to the appended claims, along with the entire equivalent scope to which such claims are entitled. Disclosures of all papers and references, including patent applications and publications, are incorporated herein by reference for all purposes. The omission of any aspect of the subject matter disclosed herein in the following claims shall not be considered an abandonment of such subject matter, nor should it be considered that the inventors did not consider such subject matter to be part of the subject matter relating to the disclosed invention.

Claims

1. In curable adhesive formulations, (i) One or more epoxy resins, (ii) One or more acidic phosphite species A curable adhesive formulation comprising, wherein at least 30% by weight of the adhesive comprises a bio-based material.

2. A-side having one or more epoxy resins, B-side having acidic phosphoric acid components The curable adhesive formulation according to claim 1, wherein the adhesive comprises at least 30% by weight of a bio-based material.

3. A-side having one or more epoxy resins, B-side having acidic phosphoric acid components A curable adhesive formulation according to claim 1 or 2, comprising, wherein the cured adhesive has at least 10% elongation when measured according to ASTM D638-10.

4. The aforementioned bio-based material (i) one or more epoxy resins, and / or (ii) The one or more acidic phosphite species or the acidic phosphate components A curable adhesive formulation according to claim 1 or 2, comprising or essentially comprising the above.

5. The curable adhesive formulation according to claim 1 or 2, wherein the biobase carbon content of the biobase material, preferably comprising or essentially comprising one or more epoxy resins and / or one or more acidic phosphite species or acidic phosphate components, is determined according to the ASTM D6866 test method, and preferably the biobase carbon content is at least 10%, more preferably at least 30%, even more preferably at least 50%, even more preferably at least 70%, and even more preferably at least 90%.

6. (i) The one or more epoxy resins are bio-based, and / or (ii) The one or more acidic phosphite species or acidic phosphate components are bio-based, according to claim 1 or 2.

7. (i) the carbon content of the biobase of the one or more epoxy resins and / or (ii) the one or more acidic phosphite species or acidic phosphate components is determined according to the ASTM D6866 test method, preferably the carbon content of the biobase is at least 10%, more preferably at least 30%, even more preferably at least 50%, even more preferably at least 70%, and even more preferably at least 90%, according to claim 6.

8. The curable adhesive formulation according to claim 1 or 2, wherein the one or more epoxy resins are bio-based and contain one or more epoxidized unsaturated oils.

9. The curable adhesive formulation according to claim 1 or 2, wherein the one or more epoxy resins are bio-based and include one or more cashew nut shell liquid-based epoxy resins, linseed oil-based epoxy resins, castor oil-based epoxy resins, soybean oil-based epoxy resins, sorbitol-based epoxy resins, isosorbide-based epoxy resins, or any combination thereof.

10. The curable adhesive formulation according to claim 8, wherein the one or more bio-based epoxy resins are present in an amount of about 30% to about 90%, preferably about 40% to about 80%, more preferably about 50% to about 70%, by weight of the curable adhesive formulation or by weight of the A-side of the curable adhesive formulation.

11. The curable adhesive formulation according to claim 1 or 2, wherein the one or more acidic phosphite species or the acidic phosphate component comprises a phosphate ester preferably selected from the group consisting of ethanol-based phosphate esters, butanol-based phosphate esters, cashew nut shell liquid-based phosphate esters, castor oil-based phosphate esters, cellulose-based phosphate esters, tetrahydrofurfuryl alcohol (THFA)-based phosphate esters, ethylene glycol-based phosphate esters, isosorbide-based phosphate esters, or any combination thereof.

12. The curable adhesive formulation according to claim 11, wherein the one or more acidic phosphite species or the acidic phosphate component is present in an amount of about 20% to about 90%, preferably about 40% to about 80%, more preferably about 50% to about 70%, by weight of the curable adhesive formulation or by weight of the B-side of the curable adhesive formulation.

13. A curable adhesive formulation according to claim 1 or 2, comprising one or more additives.

14. - The A-side of the curable adhesive formulation contains one or more additives, preferably particulate or fibrous additives, including recycled rubber, recycled structural foaming epoxy powder, metal carbonates, minerals, reinforcing fibers, hydrophobic silica, or any combination thereof, and / or - The B-side of the curable adhesive formulation contains one or more additives, including minerals, reinforcing fibers, hydrophobic silica, glass microspheres, components stable in acidic culture media, or any combination thereof. The curable adhesive formulation according to claim 13.

15. The curable adhesive formulation according to claim 1 or 2, comprising an acid preferably selected from the group consisting of phosphoric acid, citric acid, acetic acid, and any combination thereof, wherein the acid is preferably contained in the B-side of the curable adhesive formulation, and / or the acid is biobased.

16. The curable adhesive formulation according to claim 1 or 2, wherein the one or more acidic phosphite species and the acidic phosphate component are the same.

17. The curable adhesive formulation according to claim 1 or 2, wherein the adhesive undergoes an expansion of at least 50% in volume.

18. The curable adhesive formulation according to claim 1 or 2, wherein the cured adhesive has a peak stress of at least 0.02 MPa.

19. The curable adhesive formulation according to claim 1 or 2, wherein the adhesive and / or the bio-based material preferably has a bio-based content of at least 60% or more at least 80%, as determined according to the ASTM D6866 test method.

20. The curable adhesive formulation according to claim 1 or 2, wherein the A-side comprises at least 20% by weight or at least 40% by weight of a CNSL-based epoxy resin, a linseed oil-based epoxy resin, or several combinations thereof.

21. The curable adhesive formulation according to claim 1 or 2, wherein the B-side comprises at least 40% by weight or at least 80% by weight of a CNSL-based epoxy resin, a castor oil-based epoxy resin, or several combinations thereof.

22. The curable adhesive formulation according to claim 1 or 2, wherein the B-side comprises a THFA-based phosphate ester.

23. The curable adhesive formulation according to claim 1 or 2, wherein the B-side comprises epoxidized soybean oil.

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