Polyurethane composition, product thereof, and method for manufacturing the same

Abstract

To provide a two-component polyurethane composition. [Solution] A two-component polyurethane composition is provided, comprising (a) an isocyanate component containing at least one aromatic isocyanate compound, and (b) a polyol component containing at least one polyether polyol compound, sulfide-free urea or a derivative thereof, and an alcohol chain extender, wherein the isocyanate component and the polyol component have an NCO / OH ratio of 0.9:1 to 1.2:1. A product made using the polyurethane composition and a method for producing the same are also provided.

Description

[Technical Field]

[0001] The present invention relates to a two-component polyurethane composition, a product manufactured using the polyurethane composition, and a method for manufacturing the same. [Background technology]

[0002] Reaction injection molding (RIM) is a process in which two or more reactive liquid intermediates (e.g., isocyanates and polyol compounds) are separately metered and fed into a mixing head, where they are combined by high-pressure impact mixing. The mixed liquid is then poured into a mold, where it polymerizes to form a molded part. This method offers advantages such as low pressure, low temperature, and design flexibility due to the use of reactive liquid intermediates, and is used in the manufacture of a variety of products or parts, including automotive bumpers, medical products, radio and TV cabinets, furniture, sporting goods, electrical appliances, and office equipment housings.

[0003] Efforts have been made to improve polyurethane systems used in RIM applications to enhance the performance of manufactured products or components (e.g., photostability, adhesion to mold components, low odor, and mechanical strength), as well as the cost-effectiveness of the manufacturing process. To achieve good photostability, aliphatic or alicyclic isocyanates were considered to offer better photostability compared to aromatic isocyanates. However, aliphatic or alicyclic isocyanates are typically expensive, slow due to their low reactivity, and the resulting polyurethanes have inferior mechanical strength. Aromatic isocyanate-based polyurethane systems have been developed using aromatic amines as chain extenders and delayed amino catalysts to extend the operating time (open time). However, the high cost of aromatic amines and the unpleasant odors produced by amino compounds are undesirable in many applications, particularly in the automotive industry. Providing a solution that satisfies all the requirements of excellent cost-effectiveness, adhesion to mold components, photostability, low odor, and excellent mechanical strength has been challenging.

[0004] Therefore, in this field, there remains an unmet need for polyurethane systems that address the above requirements. [Overview of the Initiative]

[0005] In one embodiment, the present disclosure relates to a two-component polyurethane composition, (a) an isocyanate component, An isocyanate component comprising at least one aromatic isocyanate compound, (b) Polyol component, At least one polyether polyol compound, Urea or a derivative thereof that does not contain at least one sulfide, A polyol component comprising an alcohol chain extender, The present invention provides a two-component polyurethane composition having an isocyanate component and a polyol component having an NCO / OH ratio of 0.9:1 to 1.2:1.

[0006] In a further embodiment, the disclosure provides polyurethane articles prepared by using the two-component polyurethane compositions described herein.

[0007] In a further aspect, the present disclosure relates to a method for producing polyurethane articles, (i) an isocyanate component, To provide an isocyanate component comprising at least one aromatic isocyanate compound, (ii) Polyol component, At least one polyether polyol compound, Urea or a derivative thereof that does not contain at least one sulfide, To provide a polyol component containing an alcohol chain extender, (iii) Combining the isocyanate component with the polyol component in an NCO / OH ratio of 0.9:1 to 1.2:1 to form a reactive mixture, (iv) curing the reactive mixture to form a polyurethane-based article, and, provides a method.

[0008] In a further aspect, the present disclosure provides for the use of a two-component polyurethane composition in the manufacture of a polyurethane-based article.

[0009] It should be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the claimed invention.

Mode for Carrying Out the Invention

[0010] 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. Also, all publications, patent applications, patents, and other references mentioned herein are incorporated by reference.

[0011] As disclosed herein, "and / or" means "and, or alternatively". All ranges include the endpoints unless otherwise indicated.

[0012] As disclosed herein, all percentages mentioned herein are by weight unless otherwise specified, and the temperature is in °C.

[0013] A. Polyurethane Composition In one aspect, the present disclosure is a two-component polyurethane composition comprising: (a) an isocyanate component comprising: an isocyanate component comprising at least one aromatic isocyanate compound; and (b) a polyol component comprising: at least one polyether polyol compound; at least one urea or its derivative free of sulfides; and a chain extender alcohol, and provides a polyol component. The isocyanate component and the polyol component provide a two-component polyurethane composition having an NCO / OH ratio of 0.9:1 to 1.2:1.

[0014] As used herein, the term "two-component" means that the polyurethane composition is provided in parts that are separated from each other before the polyurethane composition is reacted. In exemplary embodiments of the present disclosure, the isocyanate component and the polyol component are prepared separately, stored, transported, supplied, and immediately or promptly combined, for example, in a mixer (e.g., a speed mixer), to form a reactive mixture. When these two components are contacted, it is contemplated that a curing reaction will begin in which the polyol groups react with the isocyanate groups to form urethane bonds. The reactive polyurethane composition formed by contacting the two components may be referred to as a "reactive liquid intermediate" or a "reactive mixture".

[0015] The isocyanate component and the polyol component have an NCO / OH ratio of 0.9:1 to 1.2:1. In some embodiments, the NCO / OH ratio is within the range obtained by combining any two of the following endpoints: 0.9:1, 1:1, 1.1:1, and 1.2:1. In some embodiments, the NCO / OH ratio is within the range of 0.9:1 to 1.1:1, 1:1 to 1.2:1, or 1:1 to 1.1:1. As used herein, the term "NCO / OH ratio" refers to the ratio of the number of isocyanate groups to the number of hydroxyl groups in the polyurethane foam composition, or more specifically, to the ratio of the number of isocyanate groups in the isocyanate component to the number of hydroxyl groups in the polyol component of the polyurethane foam composition according to the present disclosure.

[0016] Isocyanate component The isocyanate component contained in the two-component polyurethane composition of this disclosure comprises one or more aromatic isocyanate compounds, particularly aromatic polyisocyanates. Various modified or unmodified monomeric isocyanates, polymeric isocyanates, isocyanate-terminated prepolymers, and any combination thereof can be used in this disclosure.

[0017] As used herein, "isocyanate monomer" or "monomer isocyanate" is any compound containing two or more isocyanate groups. "Aromatic isocyanate" is an isocyanate containing one or more aromatic rings.

[0018] As used herein, "isocyanate-terminated prepolymer" refers to a prepolymer prepared by reacting an excess of polyisocyanate with an amination polyol or its imine / enamine, or a polyol containing a polyamine.

[0019] Examples of monomer aromatic isocyanates suitable for use in this disclosure include isomers of methylenediphenyl diisocyanate ("MDI"), e.g., 4,4-MDI, 2,4-MDI, and 2,2'-MDI, or modified MDI, e.g., carbodiimide-modified MDI or allophanate-modified MDI; isomers of toluene-diisocyanate ("TDI"), e.g., 2,4-TDI, 2,6-TDI; and isomers of naphthalene-diisocyanate ("NDI"), e.g., 1,5-ND Examples include, but are not limited to, I, m- and p-phenylenediisocyanates, chlorophenylene-2,4-diisocyanate, diphenylene-4,4'-diisocyanate, 3,3'-dimethyl-4,4'-diphenyl-diisocyanate, 3-methyldiphenyl-methane-4,4'-diisocyanate, diphenyl ether diisocyanate, 2,4,6-triisocyanatotoluene, 2,4,4'-triisocyanatodiphenyl ether, and combinations thereof.

[0020] Mixtures of isocyanates can also be used in the isocyanate component. For example, the isocyanate mixture may include monomer MDI, monomer TDI, and / or MDI or TDI-based prepolymers. In exemplary embodiments, the isocyanate component may include at least one monomer aromatic isocyanate, at least one carbodiimide-modified monomer isocyanate, and a mixture of monomer aromatic isocyanates and at least one prepolymer of a short-chain diol. In another exemplary embodiment, the isocyanate component may include a mixture of different monomer MDIs, carbodiimide-modified monomer MDIs, and short-chain diol-based monomer MDI pseudoprepolymers. The short-chain diol may include two functional hydroxyl groups and a polyol having a molecular weight up to 300 g / mol. In some embodiments, the short-chain diol is a C2-C12 diol (i.e., containing 2-12 carbon atoms), for example, a C2-C10 diol, or a C2-C8 diol. In some embodiments, the short-chain diol is of the aliphatic or alicyclic type. In some embodiments, the short-chain diols have only a hydroxyl functional group. Examples of short-chain diols include, but are not limited to, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, dipropylene glycol, tripylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, cyclohexanedimethanol, or mixtures thereof.

[0021] The aromatic isocyanate compound is present in an amount of at least 70% by weight of the isocyanate component, for example, at least 75% by weight, at least 80% by weight, at least 85% by weight, or at least 90% by weight.

[0022] Compounds having isocyanate groups, such as aromatic isocyanate compounds, can be characterized by a parameter "%NCO" or "-NCO content," which is the amount of isocyanate groups by weight of the compound. In some embodiments, aromatic isocyanate compounds have a free -NCO content of 12% to 32% by weight of the aromatic isocyanate compound, for example, 15% to 32% by weight or 12% to 28% by weight.

[0023] In some embodiments, the aromatic isocyanate has a viscosity of less than 1500 mPa·s at room temperature, for example, less than 1400 mPa·s or less than 1300 mPa·s.

[0024] The isocyanate component may optionally include one or more additional auxiliaries and / or additives for a specific function or purpose. In some embodiments, the isocyanate component may include a peroxide decomposer to obtain better weather resistance. For example, aliphatic or aromatic organic phosphite type peroxide decomposers may be useful. In some embodiments, the isocyanate component may optionally include one or more of the following: defoamers, foam stabilizers, antistatic reagents, plasticizers, flame retardants, fillers, colorants, pigments, etc. In exemplary embodiments, the pigment is preferably a dispersion of carbon black, titanium dioxide, and isoindolinone in a polyol.

[0025] Polyol components The polyol component contained in the two-component polyurethane composition of this disclosure comprises one or more polyether polyol compounds.

[0026] Compounds containing two or more ether bonds in a straight chain of the same atom are known herein as “polyethers.” Compounds that are both polyethers and polyols are “polyether polyols.”

[0027] The polyether polyols used in the polyol component may include diols, triols, tetraols, or combinations thereof.

[0028] As used herein, the term “polyol” refers to a compound having two or more hydroxyl groups. A polyol is “diol” if it has exactly two hydroxyl groups, “triol” if it has exactly three hydroxyl groups, “tetraol” if it has exactly four hydroxyl groups, “pentanol” if it has exactly five hydroxyl groups, and so on.

[0029] The polyether polyol is at least 60% by weight of the polyol component, for example, at least 65% by weight, at least 70% by weight, at least 75% by weight, at least 80% by weight, or at least 85% by weight. In some embodiments, the polyether polyol is 60% to 95% by weight of the polyol component, for example, 65% to 90% by weight, 70% to 90% by weight, or 75% to 90% by weight.

[0030] In some embodiments, one or more polyether polyols in the polyol component have an average hydroxyl group functional value of 5 or less. In some embodiments, one or more polyether polyols in the polyol component have an average hydroxyl group functional value of 2 or more. In some embodiments, one or more polyether polyols in the polyol component have an average hydroxyl group functional value within the following endpoints, i.e., within the numerical range obtained by combining any two of 2, 2.5, 3, 3.5, 4, 4.5, and 5. In some embodiments, the polyether polyol has an average hydroxyl group functional value of 2-5, 2-4, 3-5, 4-5, or 2-3.

[0031] In some embodiments, one or more polyether polyols in the polyol component have an average molecular weight of 800 g / mol or more. In some embodiments, one or more polyether polyols in the polyol component have an average molecular weight of 12000 g / mol or less. In some embodiments, one or more polyether polyols in the polyol component have an average molecular weight within the range obtained by combining any two of the following endpoints: 800, 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, 11000, and 12000 g / mol. In some embodiments, the polyether polyol has an average molecular weight of 800-12000 g / mol, 1000-12000 g / mol, 2000-12000 g / mol, 3000-12000 g / mol, 800-11000 g / mol, 800-10000 g / mol, 800-9000 g / mol, 1000-10000 g / mol, 2000-8000 g / mol, or 3000-7000 g / mol.

[0032] In some embodiments, one or more polyether polyols in the polyol component have an average number of hydroxyl groups of 20 mg KOH / g or more. In some embodiments, one or more polyether polyols in the polyol component have an average number of hydroxyl groups of 1000 mg KOH / g or less. In some embodiments, one or more polyether polyols in the polyol component have an average number of hydroxyl groups within the following endpoints, i.e., within the numerical range obtained by combining any two of 20, 50, 100, 200, 300, 500, 700, 800, and 1000 mg KOH / g. In some embodiments, one or more polyether polyols in the polyol component have an average number of hydroxyl groups of 20 to 1000 mg KOH / g, 20 to 800 mg KOH / g, 20 to 500 mg KOH / g, or 20 to 200 mg KOH / g.

[0033] In some embodiments, the polyether polyol is a polypropylene oxide-based polyol. In some embodiments, the polyether polyol has less than 20%, preferably less than 15%, of polyethylene oxide in the total amount of polyether polyol. To facilitate efficient curing and demolding, the polyether polyol contains at least 70%, for example, at least 75%, at least 80%, or at least 85% of primary hydroxyl groups.

[0034] The polyol component contained in the two-component polyurethane composition includes urea or its derivatives that do not contain sulfides.

[0035] As used herein, the term "sulfide-free urea" refers to a urea compound that does not contain sulfur, particularly divalent sulfur, in its structure.

[0036] In some embodiments, a sulfide-free urea or derivative thereof useful in this disclosure includes the following structure:

[0037] [ka] In the formula, R a and R b These are independently H or C1~C 10 It is an aliphatic chain having an OH or NH2 terminal group. Preferred examples of urea that do not contain sulfides include urea, (2-hydroxyethyl)urea, 1,3-bis(hydroxymethyl)urea, carbamoylurea, and N,N'-methylenebis[N'-3-(hydroxymethyl)-2,5-dioxo-4-imidazolidinyl]urea.

[0038] In some embodiments, the sulfide-free urea or its derivative is present in an amount of at least 0.1% by weight of the polyol component, for example, at least 0.3% by weight, at least 0.5% by weight, or at least 1% by weight. In some embodiments, the sulfide-free urea or its derivative is present in an amount of 20% by weight or less of the polyol component, for example, 18% by weight or less, 15% by weight or less, 12% by weight or less, or 10% by weight or less. In some embodiments, the sulfide-free urea or its derivative is present in an amount of 0.1% to 20% by weight of the polyol component, for example, 0.1% to 15% by weight, 0.1% to 12% by weight, 0.2% to 12% by weight, or 0.2% to 10% by weight.

[0039] The polyol component contained in the two-component polyurethane composition of this disclosure includes an alcohol chain extender.

[0040] In some embodiments, the alcohol chain extender is at least 1% by weight of the polyol component, for example, at least 2% by weight, at least 3% by weight, at least 4% by weight, or at least 5% by weight. In some embodiments, the alcohol chain extender is 20% by weight or less of the polyol component, for example, 18% by weight or less, 15% by weight or less, 12% by weight or less, or 10% by weight or less. In some embodiments, the alcohol chain extender is 1% to 20% by weight of the polyol component, for example, 2% to 18% by weight, 3% to 15% by weight, or 4% to 12% by weight.

[0041] The alcohol chain extender contained in the polyol component may include a short-chain polyol. In some embodiments, the short-chain polyol is a C2-C12 polyol (i.e., containing 2-12 carbon atoms), for example, a C2-C10 polyol or a C2-C8 polyol. In some embodiments, the short-chain polyol is of the aliphatic or alicyclic type. In some embodiments, the short-chain polyol has only a hydroxyl functional group.

[0042] In some embodiments, the short-chain polyol contained in the polyol component has 2 to 8, for example, 2 to 7, 2 to 6, 2 to 5, or 2 to 4 hydroxyl group functional groups.

[0043] Suitable examples of short-chain polyols included in the polyol component include, but are not limited to, ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, 1,4-cyclohexanedimethanol, their isomers, or combinations thereof.

[0044] In some embodiments, the two-component polyurethane composition does not contain an aromatic amine (e.g., diethyltoluenediamine) as a chain extender. In some embodiments, the two-component polyurethane composition does not contain a sulfide-containing urea (e.g., thiourea) as a chain extender.

[0045] Various types of optional components may be present in the two-component polyurethane composition according to this disclosure.

[0046] One or more catalysts can be incorporated into the polyurethane composition in either the polyol component or the isocyanate component, or in both. Preferably, the catalyst includes an organometallic catalyst.

[0047] Suitable organometallic catalysts for use in this disclosure include, but are not limited to, organotin(II or IV) catalysts, organobismuth(III) catalysts, organozinc(II) catalysts, and combinations thereof.

[0048] In certain embodiments, the organotin (II or IV) catalyst is of formula (1),

[0049] [ka] Equation (2),

[0050] [ka] or formula (3),

[0051] [Chemical formula] having, wherein, R1 is a C1-C8 alkyl group, R2 is a linear or branched C 13 -C 19 alkyl or alkenyl group, or a linear or branched C1-C 19 alkyl or alkenyl group, preferably a C7-C 19 alkyl or alkenyl group having at least one isocyanate-reactive group, particularly one or more OH - , NH - and / or NH2 - substituted groups, any of which.

[0052] In another specific embodiment, the organobismuth(III) catalyst is of formula (4),

[0053] [Chemical formula] having, wherein, m = 0-2, p = 1-3, m + p = 3, R1 is a C1-C8 alkyl group, R2 is a linear or branched C​​​​​​​​​​​​​​​​​​​​​​​​​​It has, in the formula, R2 is C1~C 19 It is an alkyl or alkenyl group, and may be linear or branched, and may be substituted or unsubstituted. Preferably, R2 is C1-C 12 The alkyl or alkenyl group is preferred because these zinc catalysts are liquid and therefore have good processability.

[0056] In some embodiments in which the polyol component contains a catalyst, the catalyst is at least 0.05% by weight of the polyol component, for example, at least 0.08% by weight, at least 0.1% by weight, at least 0.12% by weight, or at least 0.15% by weight. In some embodiments in which the polyol component contains a catalyst, the catalyst is 8% or less, for example, 5% or less, 3% or less, 1% or less, or 0.5% or less. In some embodiments in which the polyol component contains a catalyst, the catalyst is 0.05% to 8% by weight of the polyol component, for example, 0.05% to 5% by weight, 0.05% to 3% by weight, 0.08% to 1% by weight, or 0.1% to 0.5% by weight.

[0057] One or more antioxidants can be incorporated into the polyurethane composition in either the polyol component or the isocyanate component, or both.

[0058] Suitable antioxidants include phenolic types, organophosphites, phosphines and phosphonites, hindered amines, organoamines, organosulfur compounds, lactones and hydroxylamine compounds. In some embodiments, the antioxidant may be a primary antioxidant. As used herein, the term “primary antioxidant” refers to a molecule that can suppress free radicals in a polyethylene matrix. In preferred embodiments, the antioxidant is a sterically hindered phenolic type.

[0059] In some embodiments in which the antioxidant is contained in the polyol component, the antioxidant is at least 0.3% by weight of the polyol component, for example, at least 0.4% by weight, or at least 0.5% by weight. In some embodiments in which the antioxidant is contained in the polyol component, the antioxidant is 2% or less, for example, 1.8% or less, 1.5% or less, or 1.2% or less. In some embodiments in which the antioxidant is contained in the polyol component, the antioxidant is 0.3% to 2% by weight of the polyol component, for example, 0.3% to 1.8% by weight, 0.3% to 1.5% by weight, 0.4% to 1.2% by weight, or 0.5% to 1% by weight.

[0060] One or more UV absorbers can be incorporated into the polyurethane composition in either the polyol component or the isocyanate component, or both.

[0061] Typical UV absorbers include benzotriazole types. In some embodiments in which the UV absorber is contained in a polyol component, the UV absorber is present in an amount of at least 0.5% by weight of the polyol component, for example, at least 0.8% by weight, or at least 1.0% by weight. In some embodiments in which the UV absorber is contained in a polyol component, the UV absorber is present in an amount of 2.5% by weight or less of the polyol component, for example, 2.2% by weight or less, 2% by weight or less, or 1.8% by weight or less. In some embodiments in which the UV absorber is contained in a polyol component, the UV absorber is present in an amount of 0.5% to 2.5% by weight of the polyol component, for example, 0.5% to 2.2% by weight, 0.8% to 2.0% by weight, or 1.0% to 1.8% by weight.

[0062] One or more UV stabilizers can be incorporated into the polyurethane composition in either the polyol component or the isocyanate component, or both.

[0063] Typical UV stabilizers include hindered aliphatic light stabilizers (HALS). In some embodiments, the UV stabilizer includes substituted alicyclic amine types. In some embodiments where the UV stabilizer is contained in the polyol component, the UV stabilizer is at least 0.5% by weight of the polyol component, for example, at least 0.8% by weight, or at least 1.0% by weight. In some embodiments where the UV stabilizer is contained in the polyol component, the UV stabilizer is 2.5% by weight or less of the polyol component, for example, 2.2% by weight or less, 2% by weight or less, or 1.8% by weight or less. In some embodiments where the UV stabilizer is contained in the polyol component, the UV stabilizer is 0.5% to 2.5% by weight of the polyol component, for example, 0.5% to 2.2% by weight, 0.8% to 2.0% by weight, or 1.0% to 1.8% by weight.

[0064] Further auxiliary agents and / or additives for specific functions or purposes may be included in the polyurethane composition. For example, the polyol component may optionally contain one or more of the following: defoamers, foam stabilizers, antistatic reagents, plasticizers, flame retardants, fillers, colorants, pigments, etc. In exemplary embodiments, the pigment is preferably a dispersion of carbon black or titanium dioxide in the polyol.

[0065] B. Polyurethane-based articles In a further embodiment, the disclosure provides polyurethane articles prepared by using the two-component polyurethane compositions described herein.

[0066] In some embodiments, the product may be a molded polyurethane article. In some embodiments, the polyurethane article is manufactured by a molding process, such as an elastomer polyurethane molding process. In some embodiments, the polyurethane article can be manufactured using the two-component polyurethane compositions described herein by processes including, but not limited to, vacuum casting, liquid injection molding (LIM), reaction injection molding (RIM), resin transfer molding (RTM), and automated pressurized gelling (APG). In some embodiments, the polyurethane article is manufactured by a RIM process.

[0067] C. Fabrication of polyurethane-based articles In a further aspect, the present disclosure relates to a method for producing polyurethane articles, (i) an isocyanate component, To provide an isocyanate component comprising at least one aromatic isocyanate compound, (ii) Polyol component, At least one polyether polyol compound, Urea or a derivative thereof that does not contain at least one sulfide, To provide a polyol component containing an alcohol chain extender, (iii) Combining the isocyanate component with the polyol component in an NCO / OH ratio of 0.9:1 to 1.2:1 to form a reactive mixture, (iv) A method is provided which includes curing a reactive mixture to form a polyurethane article.

[0068] In some embodiments, the NCO / OH ratio is within the range obtained by combining any two of the following endpoints: 0.9:1, 1:1, 1.1:1, and 1.2:1. In some embodiments, the NCO / OH ratio is within the range of 0.9:1 to 1.1:1, 1:1 to 1.2:1, or 1:1 to 1.1:1.

[0069] Preferably, the method is carried out by using the two-component polyurethane composition according to the present disclosure.

[0070] Prior to the combination process, the isocyanate component and the polyol component are provided in portions that are separated from each other, for example, stored or placed in different containers or supply containers.

[0071] In the combination process, the isocyanate component and the polyol component are brought into contact and mixed, for example, in a mixer (e.g., a speed mixer), to form a reactive mixture. The reactive mixture can then be cured to form a polyurethane article.

[0072] In some embodiments, the method may further include a molding step in which the reactive mixture is injected immediately after it is formed in a mold (for example, within 5 minutes, preferably within 1 minute, more preferably within 30 seconds), and the reactive mixture is cured to form a molded article.

[0073] In some embodiments of the method, which include a molding step, the molding step is carried out at ambient temperature, generally 15°C to 35°C, for example, 20°C to 25°C.

[0074] In some embodiments of the method, which includes a molding step, the method may further include a demolding step in which the molded article is removed from the mold. The demolded article can be further processed, for example, by polishing, drilling, or assembling into a desired product or part for use in applications such as automotive bumpers, medical products, radio and TV cabinets, furniture, sporting goods, electrical appliances, and office equipment housings.

[0075] In some embodiments, the method is carried out via a molding process, such as an elastomer polyurethane molding process. In some embodiments, the method is carried out via a process that includes, but is not limited to, vacuum casting, liquid injection molding (LIM), reaction injection molding (RIM), resin transfer molding (RTM), and automated pressurized gelling (APG). In some embodiments, the reaction is carried out via a RIM process.

[0076] D. Application of polyurethane compositions In a further embodiment, the disclosure provides the use of a two-component polyurethane composition in the manufacture of polyurethane articles.

[0077] In some embodiments, the polyurethane article is a molded article. In some embodiments, the polyurethane article is manufactured by using the two-component polyurethane composition and / or method described above. In some embodiments, the molded article is manufactured by a RIM process.

[0078] Surprisingly, the inventors have found that polyurethane articles produced by the described method or by using the two-component polyurethane composition according to this disclosure offer excellent cost-effectiveness, adhesion to mold components, photostability, low odor, and superior mechanical strength.

[0079] In some embodiments, polyurethane articles manufactured according to this disclosure have a Shore A hardness of 75A to 100A, for example, 85A to 100A, or 90A to 100A, when measured using a Shore A analyzer in the ASTM D2240 manner.

[0080] In some embodiments, polyurethane articles manufactured according to this disclosure have a tensile strength greater than 10 MPa when measured according to ASTM D638.

[0081] In some embodiments, polyurethane articles manufactured according to this disclosure have an extreme elongation of more than 200%, for example, more than 210% or more than 220%, when measured according to ASTM D638.

[0082] In some embodiments, polyurethane articles manufactured according to this disclosure have an odor score of Grade 6 or higher, preferably Grade 7 or higher, when evaluated according to GMW3205-2016. [Examples]

[0083] Next, some embodiments of the present disclosure will be described in the following examples, all parts and percentages are by weight unless otherwise specified.

[0084] 1. Raw materials The raw materials used in the examples are listed in Table 1.

[0085] [Table 1]

[0086] 2. Experiment 2.1 Preparation of molded polyurethane elastomers Polyurethane elastomer molding was prepared by mixing the polyol component and prepolymer component using a speed mixer at 3000 rpm for 6 seconds, and then pouring the mixture into an open vertical aluminum mold at room temperature. The system was then cured at room temperature for 24 hours, and after demolding, a PU molded product was obtained. Test specimens were then cut and sent for evaluation of physical properties, as well as thermal and UV stability.

[0087] 2.2 Physical properties The hardness of the polyurethane was characterized four times in parallel for each polyurethane sample using a Shore A analyzer according to the ASTM D2240 method. Specimens for tensile strength and elongation at break were prepared according to ASTM D638. Prior to testing, the specimens were conditioned in an ASTM laboratory for 16 hours (23°C, 50% RH). The samples were tested under tension using pneumatic grips at a crosshead displacement rate of 50 mm / min. Ten specimens were used for each test.

[0088] 2.3 UV stability (a) Exposure to ultraviolet light obtained by using a xenon lamp and a suitable filter. (b) 0.55 W / m at 340 nm 2 Irradiance. (c) Thermometer temperature setting: 70±2℃. (d) Spraying conditions: Water vapor at 50±2℃. (e) Spraying frequency (exposed surface of test specimen only): Sprayed for 120 minutes, then no spraying for 102 minutes. (f) Relative humidity: 50% ± 5%, no spraying period.

[0089] The UV stability of polyurethane is evaluated using the change in the yellow index (ΔYI) after 72 hours of irradiation.

[0090] 2.4 Adhesion performance The ceramic-coated glass was first cleaned with anhydrous alcohol. After 2 minutes, the pretreatment agent EFTEC® DV 646 was applied to the surface using a brush. After drying for 15 minutes under a draft of air with a face velocity of 0.5 m / s, the primer EFTEC® DV 930 was applied to the pretreated surface within 2 hours. Within 2 hours of the primer application, a liquid mixture of isocyanate and various compound polyols was mixed and poured onto the treated surface. The experimental glass was allowed to cure at room temperature, and the peel strength at 90° was measured using an Instron apparatus at room temperature.

[0091] 2.5 Odor Evaluation 10cm x 10cm plates of polyurethane with different formulations were cast and cured at room temperature for 24 hours. The odor performance of each plate was evaluated according to GMW3205-2016, and each sample was scored according to the following criteria.

[0092] Note: Nomenclature for rating scales:

[0093] [Table 2]

[0094] 3. Results and Discussion The polyol and prepolymer components were prepared in advance before the polyurethane elastomer was manufactured. The compositions are summarized in Table 2.

[0095] When comparing E-01 or E-02, which utilize thiourea, with E-05 or E-06, which utilize an equal amount of urea, the tensile strength, elongation, and adhesive properties were similar. However, the samples containing thiourea had a strong (unpleasant) odor, and therefore the odor performance was scored as 4 according to GMW3205-2016. Furthermore, these samples containing thiourea turned dark yellow after UV irradiation (yellow index of 31-46 after 72 hours of irradiation), while those made from urea showed much better odor performance (score of 7 according to GMW3205-2016) and higher UV resistance (yellow index of <1 after 72 hours of UV irradiation).

[0096] Comparing Comparative Example E-03, which contains an aromatic amine (DETDA), with Example E-07 of the present invention, which contains an equimolar amount of urea, E-07 is less expensive due to the much lower price of urea compared to the aromatic amine, has higher UV resistance (yellow index <1 after 72 hours of UV irradiation), and has better odor performance (score of 7 compared to 6 for E-03, which showed a slightly worse odor).

[0097] When comparing Comparative Example E-04, which contains only ethylene glycol (MEG), with Examples E-05 to E-08 of the present invention, which contain different amounts of urea or a urea derivative such as bis(hydroxymethyl)urea, the examples of the present invention showed much higher tensile strength, elongation at break, peel strength, and UV stability, while the cost and odor performance were similar.

[0098] [Table 3] Note: a. Star ( * The following shows comparative examples. b. Using an Instron device 90 o The peel strength was determined by [the specified method]. c. Odor was determined according to GMW3205-2016. d. Yellow index obtained after 72 hours of irradiation.

[0099] 4. Conclusion This disclosure provides a two-component polyurethane composition comprising an isocyanate component containing at least one aromatic isocyanate, and a polyol component containing at least one polyether polyol, one sulfide-free urea or its derivative, and at least one alcohol chain extender.

[0100] The two-component polyurethane compositions provided herein are useful for applications (e.g., RIM processes) that seek high performance such as excellent cost-effectiveness, adhesion to mold internal components, photostability, low odor, and excellent mechanical strength of the products or components manufactured thereby.

Claims

1. A two-component polyurethane composition, (a) an isocyanate component, An isocyanate component comprising at least one aromatic isocyanate compound, (b) Polyol component, At least one polyether polyol compound, Urea or its derivatives that do not contain sulfides, A polyol component comprising an alcohol chain extender, The isocyanate component and the polyol component have an NCO / OH ratio of 0.9:1 to 1.2:1, making it a two-component polyurethane composition.

2. The aforementioned urea or derivative thereof, which does not contain sulfides, comprises the structure of the following formula: 【Chemistry 1】 In the formula, R ａ and R ｂ H or C １ ~C １０ It is an aliphatic chain with OH or NH as terminal groups. ２ A two-component polyurethane composition according to claim 1, having the following characteristics.

3. The two-component polyurethane composition according to claim 1, wherein the urea or derivative thereof that does not contain the sulfide is present in an amount of 0.1% to 20% by weight of the polyol component.

4. The two-component polyurethane composition according to claim 1, wherein the at least one aromatic isocyanate compound is selected from the group consisting of modified or unmodified monomer isocyanates, polymer isocyanates, isocyanate-terminated prepolymers, and any combination thereof.

5. The two-component polyurethane composition according to claim 1, wherein the isocyanate component comprises at least one monomer aromatic isocyanate, at least one carbodiimide-modified monomer isocyanate, and a mixture of a monomer aromatic isocyanate and at least one prepolymer of a C2-C12 diol.

6. The two-component polyurethane composition according to claim 1, wherein the at least one aromatic isocyanate compound has an NCO content of 12% to 32% by weight of the aromatic isocyanate compound.

7. The two-component polyurethane composition according to claim 1, wherein the at least one polyether polyol has an average hydroxyl group functional value of 2 to 5.

8. The two-component polyurethane composition according to claim 1, wherein the at least one polyether polyol has an average molecular weight of 800 to 12000 g / mol.

9. The two-component polyurethane composition according to claim 1, wherein the alcohol chain extender comprises a C2-C12 polyol.

10. A polyurethane article manufactured by using the two-component polyurethane composition described in claim 1.

11. A method for preparing polyurethane articles, (i) an isocyanate component, To provide an isocyanate component comprising at least one aromatic isocyanate compound, (ii) Polyol component, At least one polyether polyol compound, Urea or its derivatives that do not contain sulfides, To provide a polyol component containing an alcohol chain extender, (iii) The isocyanate component is combined with the polyol component in an NCO / OH ratio of 0.9:1 to 1.2:1 to form a reactive mixture, (iv) A method comprising curing the reactive mixture to form a polyurethane article.

Images