Aqueous dispersion of polyurethane or polyurethane urea, and preparation method therefor and use thereof

Abstract

The present invention relates to the technical field of adhesives, and provides an aqueous dispersion of polyurethane or polyurethane urea, and a preparation method therefor and a use thereof. The aqueous dispersion provided by the present invention is used as an effective component of an adhesive, and can achieve better damp-heat resistance and hydrolysis resistance and simultaneously achieve good initial adhesion. The aqueous dispersion provided by the present invention is prepared by reacting a composition comprising the following components: a) at least one siloxane compound; b) at least one polyol; c) at least one polyisocyanate; d) at least one hydrophilic compound; e) at least one nonionic hydrophilic compound; and an optional component f): at least one compound containing 1 to 3 amino groups and containing no COOH group. Optionally, the raw materials for preparing the aqueous dispersion further comprise an optional component g): at least one compound containing a COOH group and 1 to 3 amino groups or hydroxyl groups at the same time. Moreover, the acid value of the aqueous dispersion is between 0.005 mgKOH / g and 5 mgKOH / g.

Description

Aqueous dispersion of polyurethane or polyurethane urea and its preparation method and application Technical Field

[0001] The present invention belongs to the technical field of adhesives, and in particular relates to a water dispersion of polyurethane or polyurethane urea and a preparation method and application thereof. Background Art

[0002] During the shoe manufacturing process, adhesives are essential for bonding the outsole and midsole, the sole and upper, or the upper fabric. Two-component adhesives are currently the most common method. These adhesives consist of two components, polyurethane adhesive and a curing agent. Before use, the two components must be evenly mixed in a specific ratio. The polyurethane adhesive, as the primary component of the shoe adhesive, provides adequate adhesion to various shoe materials. The curing agent connects two or more polyurethane molecules, creating a chemical cross-linking effect and improving the adhesive's durability.

[0003] US4870129 discloses an aqueous dispersion of polyurethane or polyurethane-urea that incorporates hydroxyl groups into the molecular chain. This dispersion, when combined with an isocyanate curing agent, increases the crosslink density through the reaction between the isocyanate and hydroxyl groups, significantly improving bond strength and heat resistance. However, the addition of the curing agent shortens the open time of the finished adhesive. Excessive curing can lead to wasteful production, increasing production costs. Furthermore, the curing agent contains a large number of NCO groups, making it highly toxic and potentially harmful to the environment and the health of downstream workers.

[0004] CN110016117 discloses a preparation method and application of a self-crosslinking polyurethane dispersion. The dispersion is formed by reacting triphenylmethanol and a polyurethane prepolymer. It maintains chemical stability for a long time at room temperature. When the temperature rises to 70-80°C, the polyurethane begins to unblock, and the triphenylmethanol falls off from the main chain over a large area, unblocking a polyurethane containing an NCO group at the end. The NCO then reacts chemically with the structure containing active hydrogen in the polyurethane chain to form a stable chemical crosslinked structure, thereby enhancing its adhesive effect. However, since the blocking agent triphenylmethanol has a deblocking temperature of only 70-80°C, and the blocking-deblocking process is a reversible reaction, this places higher demands on the storage environment of the emulsion and the production and transportation of shoe glue. During use, the triphenylmethanol produced by unblocking has a boiling point of up to 380°C and will remain in the glue, posing a risk of potential toxicity and environmental pollution, and its widespread use is limited.

[0005] Patents such as DE4410557 and DE19954500 propose introducing carboxylates into aqueous dispersions of polyurethane or polyurethaneurea, then compounding them with carbodiimide. The reaction between the carboxylic acid and carbodiimide increases the crosslinking density and thus the strength of the adhesive. Carboxylates are obtained by adding dimethylolpropionic acid to the polyurethane or polyurethaneurea and then neutralizing it with a tertiary amine. However, these dispersions contain a large number of carboxyl groups and have poor hydrolysis resistance. Adding the additional component, carbodiimide, produces a large amount of crosslinking components, which typically results in decreased adhesion and, in turn, increased adhesive delamination during bonding.

[0006] CN101381451 describes a self-crosslinking aqueous polyurethane dispersion obtained by adding a sterically hindered siloxane. While the addition of a sterically hindered siloxane structure ensures the stable storage of the self-crosslinking dispersion, it also results in a slow crosslinking reaction during use, failing to achieve the desired properties. The patent also points out that dispersions prepared using non-sterically hindered siloxane crosslinking monomers containing methoxy or ethoxy groups lack stable storage and self-crosslinking properties.

[0007] CN108250390 describes that a self-crosslinking aqueous polyurethane dispersion can be obtained by adding non-sterically hindered siloxanes. However, because the trimethoxy or triethoxy groups are affected by steric hindrance, the silane groups cannot be completely hydrolyzed and crosslinked, or the degree of crosslinking of the dimethoxy or diethoxy groups is insufficient. As a result, its resistance is still somewhat lower than that of a two-component system, limiting its use in high-end shoes with high resistance requirements.

[0008] CN109081897 describes a method for preparing a water-based polyurethane with excellent moisture and heat resistance. The method involves introducing two silanes into the main chain and side chains of the polyurethane, allowing the siloxanes to hydrolyze and crosslink with each other, thereby achieving moisture and heat resistance. However, the water-based polyurethane prepared by this method suffers from excessive cross-linking, resulting in poor adhesion and a tendency for the adhesive to delaminate during lamination, increasing the rework rate and significantly reducing shoe production efficiency.

[0009] CN112079989 discloses a method for preparing water-based polyurethane, which introduces a compound containing a COOH group that can react with isocyanate, and then uses it in combination with carbodiimide to improve the initial adhesion of the adhesive. The acid value content is high, and the use of carboxyl groups leads to a decrease in the hydrolysis resistance of the water-based polyurethane dispersion and a short shelf life.

[0010] Summary of the Invention

[0011] The present invention provides an aqueous dispersion of polyurethane or polyurethane urea, a preparation method thereof, and an application thereof. The aqueous dispersion provided by the present invention, as an effective component of an adhesive, can achieve excellent moisture and heat resistance and hydrolysis resistance without the use of a curing agent, while also achieving good initial tack.

[0012] To achieve its purpose, the present invention provides the following technical solutions:

[0013] The present invention provides an aqueous dispersion of polyurethane or polyurethane urea, which is prepared by reacting a composition comprising the following components:

[0014] a) at least one siloxane compound having the general formula

[0015] wherein the group R contains at least one NCO reactive group, and at least two of the groups R1, R2 and R3 are the same or different alkoxy groups, and the alkoxy groups are selected from methoxy or ethoxy;

[0016] b) at least one polyol having a functionality of 2 to 4;

[0017] c) at least one polyisocyanate;

[0018] d) at least one hydrophilic compound, wherein the hydrophilic group of the hydrophilic compound comprises one or more of an ionic group or a potentially ionic group, and the hydrophilic compound contains 2-3 NCO reactive groups;

[0019] e) at least one nonionic hydrophilic compound that is reactive with NCO and is monofunctional;

[0020] Optional component f): at least one compound containing 1 to 3 amino groups and no COOH groups;

[0021] Optionally, the raw materials for preparing the aqueous dispersion further include optional component g): at least one compound containing a COOH group and 1 to 3 amino or hydroxyl groups;

[0022] Based on the total mass of components a) to g), the amounts of the components are: component a) 0.05-1.25 wt%, component b) 75-92 wt%, component c) 7-17 wt%, component d) 0.5-2.5 wt%, component e) 0.02-1.5 wt%, component f) 0-2.5 wt%, component g) 0-3 wt%;

[0023] Furthermore, the acid value of the aqueous dispersion is between 0.005 mgKOH / g and 5 mgKOH / g, preferably between 0.01 mgKOH / g and 3 mgKOH / g, and more preferably between 0.02 mgKOH / g and 3 mgKOH / g.

[0024] In some preferred embodiments, during the preparation of the aqueous dispersion, the preparation of the isocyanate-terminated prepolymer is carried out in the presence of a trace amount of alkali metal ions, and based on the total mass of the isocyanate-terminated prepolymer being 100%, the content of the alkali metal ions is 0.1ppm-30ppm, preferably 0.1-23ppm, and the alkali metal ions are selected from Na + and / or K + ;

[0025] The isocyanate-terminated prepolymer is obtained by reacting raw materials comprising at least component b), component c) and component e).

[0026] In some embodiments, in the component a), the NCO-reactive group in the group R is selected from one or more of a hydroxyl group, a primary amino group, and a secondary amino group; preferably, the component a) has at least one primary or secondary amino group; preferably, the group R is a saturated fatty alkyl chain having at least one primary and / or secondary amino group, and optionally carrying an alkoxy group;

[0027] Preferably, the component a) is selected from one or more of bis(3-trimethoxysilylpropyl)amine, bis(3-triethoxysilylpropyl)amine, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldiethoxysilane, 3-aminopropyltrimethoxysilane, and 3-aminopropyltriethoxysilane.

[0028] In some embodiments, in the component b), the number average molecular weight of the polyol is 500 to 10,000, preferably 1,000 to 5,000, and more preferably 1,000 to 4,000;

[0029] Preferably, the polyol is selected from one or more of diols, triols and tetraols;

[0030] Further preferably, the polyol is selected from one or more of polyadipate series polyester polyols, polycaprolactone polyols and polycarbonate polyols;

[0031] More preferably, the polyol is selected from polyadipic acid series polyester diols with a number average molecular weight of 1000 to 4000 and a functionality of 2.

[0032] In some embodiments, in the component c), the polyisocyanate is selected from tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,4-diisocyanato-cyclohexane, isophorone diisocyanate, 4,4'-diisocyanato-dicyclohexyl-methane, 4,4'-diisocyanato-2,2-dicyclohexylpropane, 1,4-diisocyanatobenzene, 2,4-diisocyanatotoluene. , 2,6-diisocyanatotoluene, 4,4'-diisocyanato-diphenylmethane, 2,2'-diisocyanatodiphenylmethane, 2,4'-diisocyanatodiphenylmethane, tetramethylxylylene diisocyanate, p-xylylene diisocyanate, p-isopropylene diisocyanate, p-phenylene diisocyanate and one or more of cyclohexane dimethylene diisocyanate; preferably hexamethylene diisocyanate and / or isophorone diisocyanate.

[0033] In some embodiments, in the component d), the hydrophilic compound is selected from one or more of N-(2-aminoethyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-3-aminopropanesulfonic acid, N-(2-aminoethyl)-3-aminopropanesulfonic acid and their alkali metal salts, alkaline earth metal salts and ammonium salts; preferably N-(2-aminoethyl)-2-aminoethanesulfonic acid salt.

[0034] In some embodiments, in the component e), the number average molecular weight of the nonionic hydrophilic compound is 200-8000, preferably 500-3000;

[0035] Preferably, the number of ethylene oxide groups in the nonionic hydrophilic compound is 4-200, more preferably 12-75;

[0036] Preferably, the nonionic hydrophilic compound is a monofunctional polyoxyethylene ether with a number average molecular weight of 200-8000 and an ethylene oxide number of 4-200, more preferably a polyethylene glycol monomethyl ether with a number average molecular weight of 500-3000 and an ethylene oxide number of 12-75.

[0037] In some embodiments, in component f), the compound containing 1-3 amino groups and no COOH group is one or more of an aliphatic amine compound and an alicyclic amine compound, preferably, the amino group contained therein is a primary amine group and / or a secondary amine group, and the compound containing 1-3 amino groups and no COOH group optionally contains a hydroxyl group;

[0038] Preferably, the component f) is selected from one or both of isophoronediamine and N-(2-hydroxyethyl)ethylenediamine.

[0039] In some embodiments, the raw materials for preparing the aqueous dispersion include the component g), and the component g) is preferably selected from one or more of monohydroxycarboxylic acid, dihydroxycarboxylic acid, dihydroxydicarboxylic acid, trihydroxycarboxylic acid, monoaminocarboxylic acid, diaminocarboxylic acid, and triaminocarboxylic acid;

[0040] Preferably, the component g) is selected from one or more of dimethylolpropionic acid, dimethylolbutanoic acid, dimethylolacetic acid, dihydroxysuccinic acid, hydroxypivalic acid, glycolic acid, hydroxypropionic acid, lysine, lactic acid, 6-aminocaproic acid, alanine, N-(2-aminoethyl)-β-alanine, aminoundecanoic acid, 8-aminooctanoic acid, 5-aminovaleric acid, 4-aminobutyric acid, aminobenzoic acid, 4-aminomethylcyclohexanecarboxylic acid, 2-aminocaproic acid, 4-aminocyclohexanecarboxylic acid, 12-aminododecanoic acid and 9-aminononanecarboxylic acid, more preferably one or more of dimethylolpropionic acid, lactic acid and lysine.

[0041] The present invention also provides a method for preparing the aqueous dispersion of the polyurethane or polyurethane urea described above, the method comprising the following steps:

[0042] S1: reacting the components b), c) and e) to form an isocyanate-terminated prepolymer;

[0043] S2: After dissolution, continue to react the prepolymer with the component d), component a) and optionally the component f), and then disperse with water;

[0044] In step S1 and / or step S2, a solvent is optionally used that can be partially or completely removed during the dispersion or by a distillation operation after the dispersion;

[0045] The optional component g) is added at any stage of step S1 and / or step S2;

[0046] Meanwhile, during the preparation of the aqueous dispersion, the acid value of the aqueous dispersion is controlled to be between 0.005 mgKOH / g and 5 mgKOH / g, preferably between 0.01 mgKOH / g and 3 mgKOH / g, and more preferably between 0.02 mgKOH / g and 3 mgKOH / g.

[0047] In some embodiments, in step S1, the preparation of the isocyanate-terminated prepolymer is carried out in the presence of a trace amount of alkali metal ions, and the content of the alkali metal ions is 0.1ppm-30ppm based on the total mass of the isocyanate-terminated prepolymer as 100%, and the alkali metal ions are selected from Na + and / or K + .

[0048] The present invention also provides use of the aqueous dispersion described above or the aqueous dispersion prepared by the method described above in the preparation of adhesives and sealants.

[0049] The technical solution provided by the present invention has the following beneficial effects:

[0050] The polyurethane or polyurethane urea aqueous dispersion provided by the present invention introduces a non-sterically hindered siloxane functional monomer into its reaction system, and simultaneously controls the acid value of the dispersion to be between 0.005 mgKOH / g and 5 mgKOH / g. When used as an active ingredient in an adhesive, the polyurethane or polyurethane urea aqueous dispersion can achieve excellent moisture and heat resistance and hydrolysis resistance without the use of a curing agent, while also having good initial tack, an extended shelf life, and excellent storage stability, and its performance is comparable to that of a two-component system. DETAILED DESCRIPTION

[0051] In order to facilitate the understanding of the present invention, the present invention will be further described below in conjunction with examples. It should be understood that the following examples are only for a better understanding of the present invention and do not mean that the present invention is limited to the following examples.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention pertains. The term "and / or" as may be used herein includes any and all combinations of one or more of the associated listed items.

[0053] The present invention provides an aqueous dispersion of polyurethane or polyurethane urea, which is prepared by reacting a composition comprising the following components:

[0054] a) at least one siloxane compound having the general formula

[0055] wherein the group R contains at least one NCO reactive group, and at least two of the groups R1, R2 and R3 are the same or different alkoxy groups, and the alkoxy groups are selected from methoxy or ethoxy;

[0056] b) at least one polyol having a functionality of 2 to 4;

[0057] c) at least one polyisocyanate;

[0058] d) at least one hydrophilic compound, wherein the hydrophilic group of the hydrophilic compound comprises one or more of an ionic group or a potentially ionic group, and the hydrophilic compound contains 2-3 NCO reactive groups;

[0059] e) at least one nonionic hydrophilic compound that is reactive with NCO and is monofunctional;

[0060] Optional component f): at least one compound containing 1 to 3 amino groups and no COOH groups;

[0061] Optionally, the raw materials for preparing the aqueous dispersion further include optional component g): at least one compound containing a COOH group and simultaneously containing 1 to 3 amino groups or hydroxyl groups;

[0062] Based on the total mass of components a) to g), the amounts of the components are: component a) 0.05-1.25 wt%, component b) 75-92 wt%, component c) 7-17 wt%, component d) 0.5-2.5 wt%, component e) 0.02-1.5 wt%, component f) 0-2.5 wt%, component g) 0-3 wt%;

[0063] Furthermore, the acid value of the aqueous dispersion is between 0.005 mgKOH / g and 5 mgKOH / g.

[0064] The present invention provides an aqueous dispersion of a self-crosslinkable polyurethane or polyurethane urea. A non-sterically hindered siloxane functional monomer is introduced into the reaction system, and the acid value of the dispersion is controlled to be between 0.005 mgKOH / g and 5 mgKOH / g. The aqueous dispersion obtained by the reaction system of the present invention and meeting the above-mentioned specific acid value requirements can be used as an active ingredient of an adhesive. Without the use of a curing agent, the aqueous dispersion can obtain excellent moisture and heat resistance and hydrolysis resistance, while also having good initial tack, an extended shelf life, and excellent storage stability. Its performance is comparable to that of a two-component system.

[0065] In conventional practice in the art, to prevent hydrolysis of polyurethane or polyurethane-urea aqueous dispersions and thus prevent further degradation of their resistance, it is generally desirable to control the acid value of the aqueous dispersion to be as low as possible. However, after extensive research, the present inventors unexpectedly discovered that by controlling the acid value of the polyurethane or polyurethane-urea dispersion within a certain range, through synergistic action with the aforementioned component a) the siloxane compound, the hydrolysis resistance of the polyurethane or polyurethane-urea aqueous dispersion does not decrease, and instead surprisingly outperforms aqueous dispersions having an excessively low acid value or no acid value at all.

[0066] The polyurethane or polyurethane-urea of ​​the present invention contains non-sterically hindered siloxane groups in its side chains, and the acid value of the dispersion is controlled within a certain range (0.005 mgKOH / g-5 mgKOH / g). During the activation, drying, and curing processes during application, as water evaporates, the probability of collision with the silane coupling agent increases. The slightly acidic conditions make the silane coupling agent more susceptible to hydrolysis, condensation, and crosslinking. Combined with a specific acid value, it can provide better substrate adhesion, superior moisture and heat resistance, and better storage stability without sacrificing viscosity. However, if the acid value of the dispersion is too low, it cannot form a synergistic effect with the siloxane compound (component a), resulting in insufficient moisture and heat resistance. If the acid value of the dispersion is too high, the presence of excessive COOH in the system will result in poor hydrolysis resistance of the dispersion. Preferably, the acid value of the aqueous dispersion is controlled between 0.01 mgKOH / g and 3 mgKOH / g, more preferably between 0.02 mgKOH / g and 3 mgKOH / g, to facilitate better synergy with component a) and to achieve both better initial tack and moisture-heat resistance.

[0067] In some embodiments, the acid value of the aqueous dispersion is, for example, 0.005 mgKOH / g, 0.008 mgKOH / g, 0.01 mgKOH / g, 0.02 mgKOH / g, 0.05 mgKOH / g, 0.10 mgKOH / g, 0.50 mgKOH / g, 1.00 mgKOH / g, 1.25 mgKOH / g, 1.50 mgKOH / g, 2.00 mgKOH / g, 2.50 mgKOH / g, 3.00 mgKOH / g, etc.

[0068] In some embodiments, based on the total mass of the components a) to g), the amount of component a) is, for example, 0.05 wt%, 0.07 wt%, 0.10 wt%, 0.50 wt%, 0.70 wt%, 1.00 wt%, 1.25 wt%, etc. In some embodiments, the amount of component b) is, for example, 75 wt%, 78 wt%, 80 wt%, 82 wt%, 85 wt%, 87 wt%, 89 wt%, 92 wt%, etc. In some embodiments, the amount of component c) is, for example, 7 wt%, 10 wt%, 12 wt%, 15 wt%, 17 wt%, etc. In some embodiments, the amount of component d) is, for example, 0.5 wt%, 0.7 wt%, 1.0 wt%, 1.5 wt%, 2.0 wt%, 2.5 wt%, etc. In some embodiments, the amount of component e) is, for example, 0.02 wt%, 0.10 wt%, 0.50 wt%, 1.0 wt%, 1.5 wt%, etc. In some embodiments, the amount of component f) is, for example, 0 wt%, 0.01 wt%, 0.05 wt%, 0.07 wt%, 0.10 wt%, 0.50 wt%, 1.00 wt%, 1.50 wt%, 2.00 wt%, 2.50 wt%, etc. In some embodiments, the amount of component g) is, for example, 0 wt%, 0.005 wt%, 0.01 wt%, 0.02 wt%, 0.05 wt%, 0.07 wt%, 0.10 wt%, 0.50 wt%, 1.00 wt%, 1.50 wt%, 2.00 wt%, 2.50 wt%, 3.00 wt%, etc.

[0069] In a preferred embodiment, during the preparation of the aqueous dispersion, the preparation of the isocyanate-terminated prepolymer is carried out in the presence of a trace amount of alkali metal ions, and based on the total mass of the isocyanate-terminated prepolymer as 100%, the content of the alkali metal ions is 0.1ppm-30ppm, for example, 0.1ppm, 1ppm, 5ppm, 10ppm, 15ppm, 20ppm, 23ppm, 25ppm, 30ppm, etc., preferably 0.1-23ppm, and the alkali metal ions are selected from Na + and / or K +The isocyanate-terminated prepolymer is obtained by reacting raw materials comprising at least component b), component c), and component e). There are no particular restrictions on the method for introducing the alkali metal ions, as long as the reaction process for preparing the isocyanate-terminated prepolymer is carried out in the presence of 0.1ppm-30ppm of alkali metal ions. In some examples, the alkali metal ions may be, for example, one or more of, but not limited to, sodium hydroxide, potassium hydroxide, sodium alkoxide, and potassium alkoxide. Alternatively, the alkali metal ions may be introduced in other ways, such as by introducing the aforementioned amount of alkali metal ions together with the raw materials required for the reaction. In some embodiments, the aforementioned alkali metal ions are introduced before or during the reaction.

[0070] In some embodiments, in the component a), the NCO-reactive group in the group R is selected from one or more of a hydroxyl group, a primary amino group, and a secondary amino group; preferably, the component a) has at least one primary amino group or a secondary amino group; further preferably, in the component a), the group R is a saturated fatty alkyl chain having at least one primary amino group and / or a secondary amino group, and optionally carries an alkoxy group; preferably, at least two of the groups R1, R2, and R3 are alkoxy groups directly substituted by the same or different saturated fatty alkyl chains. Preferably, the component a) is selected from one or more of bis(3-trimethoxysilylpropyl)amine, bis(3-triethoxysilylpropyl)amine, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldiethoxysilane, 3-aminopropyltrimethoxysilane, and 3-aminopropyltriethoxysilane; more preferably bis(3-methoxysilylpropyl)amine, 3-aminopropyltriethoxysilane and / or N-β-(aminoethyl)-γ-aminopropyltriethoxysilane.

[0071] In some embodiments, in the component b), the number average molecular weight of the polyol is 500-10,000, preferably 1,000-5,000, and more preferably 1,000-4,000; preferably, the polyol is selected from one or more of diols, triols and tetraols, for example, one or more of diols, triols and tetraols with a number average molecular weight of 1,000-5,000; further preferably, the polyol is selected from one or more of polyadipate series polyester polyols, polycaprolactone polyols and polycarbonate polyols, for example, one or more of polyadipate series polyester polyols, polycaprolactone polyols and polycarbonate polyols with a number average molecular weight of 1,000-4,000; more preferably, the polyol is selected from polyadipate series polyester diols with a functionality of 2 and a number average molecular weight of 1,000-4,000.

[0072] In some embodiments, in the component c), the polyisocyanate is selected from tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,4-diisocyanato-cyclohexane, isophorone diisocyanate, 4,4'-diisocyanato-dicyclohexyl-methane, 4,4'-diisocyanato-2,2-dicyclohexylpropane, 1,4-diisocyanatobenzene, 2,4-diisocyanatotoluene. , 2,6-diisocyanatotoluene, 4,4'-diisocyanato-diphenylmethane, 2,2'-diisocyanatodiphenylmethane, 2,4'-diisocyanatodiphenylmethane, tetramethylxylylene diisocyanate, p-xylylene diisocyanate, p-isopropylene diisocyanate, p-phenylene diisocyanate and one or more of cyclohexane dimethylene diisocyanate; preferably hexamethylene diisocyanate and / or isophorone diisocyanate.

[0073] In some embodiments, in the component d), the hydrophilic compound is selected from but not limited to one or more of N-(2-aminoethyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-3-aminopropanesulfonic acid, N-(2-aminoethyl)-3-aminopropanesulfonic acid and their alkali metal salts, alkaline earth metal salts and ammonium salts; preferably N-(2-aminoethyl)-2-aminoethanesulfonic acid salt.

[0074] In some embodiments, in the component e), the number average molecular weight of the nonionic hydrophilic compound is 200-8000, preferably 500-3000; preferably, the number of ethylene oxides in the nonionic hydrophilic compound is 4-200, more preferably 12-75; preferably, the nonionic hydrophilic compound is a monofunctional polyoxyethylene ether having a number average molecular weight of 200-8000 and a number of ethylene oxides of 4-200, more preferably polyethylene glycol monomethyl ether having a number average molecular weight of 500-3000 and a number of ethylene oxides of 12-75.

[0075] In some embodiments, in component f), the compound containing 1-3 amino groups and no COOH group is one or more of an aliphatic amine compound and an alicyclic amine compound, preferably, the amino group contained therein is a primary amine group and / or a secondary amine group, and the compound containing 1-3 amino groups and no COOH group optionally contains a hydroxyl group; preferably, the component f) is selected from one or both of isophorone diamine and N-(2-hydroxyethyl)ethylenediamine.

[0076] The acid value of the aqueous dispersion can be achieved by adding free COOH-containing substances and / or introducing isocyanate-reactive compounds containing COOH groups into the aqueous dispersion during its preparation. Other methods can also be used to achieve the target acid value of the aqueous dispersion. However, the key is to control the acid value of the resulting aqueous dispersion to be within the range of 0.005 mgKOH / g to 5 mgKOH / g, preferably 0.01 mgKOH / g to 3 mgKOH / g, and more preferably 0.02 mgKOH / g to 3 mgKOH / g, as required by the present invention. This acid value control can synergize with component a) in the formulation system of the present invention, enabling the aqueous dispersion to achieve excellent initial tack, moisture and heat resistance, and hydrolysis resistance without the use of a curing agent. The free COOH-containing substances and isocyanate-reactive compounds containing COOH groups (i.e., component g) are preferably selected from one or more of monohydroxycarboxylic acids, dihydroxycarboxylic acids, dihydroxydicarboxylic acids, trihydroxycarboxylic acids, monoaminocarboxylic acids, diaminocarboxylic acids, and triaminocarboxylic acids. Preferably, the component g) is selected from one or more of dimethylolpropionic acid, dimethylolbutyric acid, dimethylolacetic acid, dihydroxysuccinic acid, hydroxypivalic acid, glycolic acid, hydroxypropionic acid, lysine, lactic acid, 6-aminocaproic acid, alanine, N-(2-aminoethyl)-β-alanine, aminoundecanoic acid, 8-aminooctanoic acid, 5-aminovaleric acid, 4-aminobutyric acid, aminobenzoic acid, 4-aminomethylcyclohexanecarboxylic acid, 2-aminocaproic acid, 4-aminocyclohexanecarboxylic acid, 12-aminododecanoic acid and 9-aminononanecarboxylic acid, more preferably one or more of dimethylolpropionic acid, lactic acid and lysine. The above scheme is a preferred embodiment, and those skilled in the art can also select other methods to achieve.

[0077] In some embodiments, the polyurethane or polyurethaneurea aqueous dispersion provided herein has a solids content of 30-70 wt%, preferably 45-55 wt%, with the remainder being water. In some preferred embodiments, the polyurethane or polyurethaneurea aqueous dispersion provided herein has an average particle size of 100-300 nm, preferably 160-230 nm; preferably, the pH of the polyurethane or polyurethaneurea aqueous dispersion is 4-11, preferably 7-9.

[0078] The present invention also provides a method for preparing the aqueous dispersion of the polyurethane or polyurethane urea described above, the method comprising:

[0079] S1: reacting the components b), c) and e) to form an isocyanate-terminated prepolymer;

[0080] S2: After dissolution, continue to react the prepolymer with the component d), component a) and optionally the component f), and then disperse with water;

[0081] In step S1 and / or step S2, a solvent is optionally used that can be partially or completely removed during the dispersion or by a distillation operation after the dispersion;

[0082] The optional component g) is added at any stage of step S1 and / or step S2;

[0083] Meanwhile, during the preparation of the aqueous dispersion, the acid value of the aqueous dispersion is controlled to be between 0.005 mgKOH / g and 5 mgKOH / g, preferably between 0.01 mgKOH / g and 3 mgKOH / g, and more preferably between 0.02 mgKOH / g and 3 mgKOH / g.

[0084] In the preparation process of the present invention, a specific component a) is introduced into the reaction system, and the acid value of the dispersion is controlled to be between 0.005 mgKOH / g and 5 mgKOH / g. The aqueous dispersion prepared by this process is used as an active ingredient in an adhesive. This adhesive can achieve excellent moisture and heat resistance and hydrolysis resistance while also maintaining good initial tack without the use of a curing agent.

[0085] Each of Step S1 and Step S2 can include one or more stages of reaction, and can include one or more sub-steps. For example, in Step S1, components b), c), and e) are reacted in one or more stages to form an isocyanate-terminated prepolymer. For example, in Step S2, the prepolymer is further reacted with components d), a), and optionally, f) in a single or two-stage reaction.

[0086] Where no particular description is given regarding the method for preparing the aqueous dispersion of polyurethane or polyurethane urea, the method may be carried out in accordance with conventional operations and / or processes in the art.

[0087] In some preferred implementations, as an example, the method can be specifically performed according to the following steps:

[0088] S1: First, components b), c), e) and an optional solvent are mixed and reacted at 75-85° C. until the theoretical NCO content is reached (e.g., 0.8-2.1% of the theoretical NCO content) to obtain a terminated isocyanate prepolymer; preferably, in the presence of a trace amount of alkali metal ions (Na + and / or K +), for example, based on the total mass of the isocyanate-terminated prepolymer being 100%, the content of the alkali metal ions is 0.1ppm-30ppm. S2: The isocyanate-terminated prepolymer is cooled and dissolved with a solvent, and component d), optional component f), and component a) are added at 40-50°C for reaction, and the reaction time is, for example, 15-25min. Water is added for dispersion, and the solvent used is completely or partially removed by distillation during or after dispersion. In steps S1 and S2, each component can be added in one stage or in multiple stages. Each component can be pre-dispersed in a solvent or water and then added to the reaction system, or directly added to the reaction system. When component g) is used, component g) can be added at any stage of step S1 and / or step S2. In some embodiments, the amount of solvent used is, for example, 1-2.5 times the total mass of the solid parts, and the amount of water used is, for example, 0.7-1.5 times the total mass of the solid parts.

[0089] In the process of preparing the aqueous dispersion, the solvent used, which can be partially or completely removed by distillation during or after dispersion, is selected from one or more of acetone, methyl isobutyl ketone, butanone, tetrahydrofuran, dioxane, acetonitrile, dipropylene glycol dimethyl ether and 1-methyl-2-pyrrolidone, more preferably acetone and / or butanone, further preferably acetone.

[0090] The polyurethane or polyurethane-urea provided by the present invention has non-sterically hindered siloxane segments on its side chains and a specific acid value. The aqueous dispersion provided by the present invention is stable in storage and exhibits excellent hydrolysis resistance. During activation, drying, and curing, as water evaporates, the probability of silane coupling agent collision increases. The slightly acidic conditions make the silane coupling agent more susceptible to hydrolysis, condensation, and crosslinking. The combined effects of the silane coupling agent and the specific acid value simultaneously provide good substrate adhesion, superior moisture and heat resistance, and improved storage stability.

[0091] In a preferred embodiment, in step S1, the preparation of the isocyanate-terminated prepolymer is carried out in the presence of a trace amount of alkali metal ions, and the content of the alkali metal ions is 0.1ppm-30ppm based on the total mass of the isocyanate-terminated prepolymer as 100%, and the alkali metal ions are selected from Na + and / or K + The preparation of the isocyanate-terminated prepolymer in the presence of a preferred trace amount of alkali metal ions is beneficial to improving the application properties of the final aqueous dispersion and further improving the moisture and heat resistance.

[0092] The present invention also provides the use of the aqueous dispersion described above, or the aqueous dispersion prepared by the method described above, in the preparation of adhesives and sealants. The aqueous dispersion provided by the present invention and the adhesives and sealants obtained based on the aqueous dispersion can be used to bond materials such as rubber, plastics, leather, textiles, wood, and ABS (acrylic acid-butadiene-styrene). The aqueous dispersion can be used alone or mixed with auxiliary substances and / or additives known in the art of adhesives, such as emulsifiers, antioxidants, thickeners, leveling agents, and defoaming agents.

[0093] Compared with the prior art, the polyurethane or polyurethane-urea aqueous dispersion provided by the present invention has at least the following beneficial effects:

[0094] 1. The aqueous dispersion provided by the present invention can be used as a single-component adhesive, and does not require additional curing agents such as isocyanates and carbodiimides. It is simple to operate and has no open period requirement, greatly increasing construction efficiency.

[0095] 2. The aqueous dispersion of the present invention features a low siloxane content, a well-controlled acid value, and excellent stability. Compound systems based on this dispersion exhibit superior stability and long shelf life, making it suitable for the preparation of high-quality sealants, particularly adhesives.

[0096] The technical solution of the present invention is further described below with reference to the embodiments.

[0097] Where specific experimental steps or conditions are not specified in the examples, the experiments can be carried out according to the corresponding conventional experimental steps or conditions in the art.

[0098] The main raw materials used in the following examples are described as follows. Unless otherwise specified, they are common raw materials available on the market:

[0099] Sodium methoxide: Leling Chuangli Technology Co., Ltd.;

[0100] Component a):

[0101] Silane coupling agent I:

[0102] N-(β-aminoethyl)-γ-aminopropyltriethoxysilane, Mn=264 g / mol (KH791, Nanjing Silicon Innovation Materials Co., Ltd.);

[0103] Silane coupling agent II:

[0104] Bis(3-trimethoxysilylpropyl)amine, Mn=342 g / mol (SCA-A67W, Nanjing Nengde New Materials Technology Co., Ltd.);

[0105] Silane coupling agent III:

[0106] 3-Aminopropyltriethoxysilane, Mn=221 g / mol (KH550, Nanjing Quanxi Chemical Co., Ltd.);

[0107] Component b):

[0108] Polyester polyol I: polybutylene adipate diol, M n =2000g / mol( Wanhua Chemical);

[0109] Polyester polyol II: polybutylene adipate diol, M n =3000g / mol( Wanhua Chemical);

[0110] Polycaprolactone polyol III: polycaprolactone diol, Mn = 2000 g / mol (PCL-220N, Daicel);

[0111] Polycarbonate polyol IV: polycarbonate diol, Mn = 2000 g / mol (T5652, Asahi Kasei);

[0112] Component c):

[0113] Polyisocyanate I: Hexamethylene diisocyanate ( Wanhua Chemical);

[0114] Polyisocyanate II: Isophorone diisocyanate ( Wanhua Chemical);

[0115] Component d):

[0116] N-(2-aminoethyl)-2-aminoethanesulfonate ( EVONIK, USA);

[0117] Component e):

[0118] Polyethylene glycol monomethyl ether, Mn = 1200 g / mol, (MPEG1200, LG Chem);

[0119] Component f):

[0120] Isophorone diamine (IPDA, Wanhua Chemical);

[0121] N-(2-hydroxyethyl)ethylenediamine (AEEA, BASF-YPC);

[0122] Component g):

[0123] Dimethylolpropionic acid (DMPA, Perstorp);

[0124] Lysine: (LA, Yancheng Green Chemical Co., Ltd.);

[0125] Lactic acid: Shanghai Aladdin Biochemical Technology Co., Ltd.

[0126] Example 1

[0127] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 350 g of polyester polyol I (component b)), 40 g of isocyanate I (component c)), 2 g of isocyanate II (component c)), 1.5 g of DMPA (component g)), 2.44 g of MPEG1200 (component e)), 0.02 g of sodium methoxide (the amount of sodium ions is 22 ppm of the obtained terminal isocyanate prepolymer) and 59 g of acetone were added, and the mixture was reacted at 80 ° C. Samples were taken every 1 h to measure NCO%, and the reaction was stopped after 3 h until NCO% reached a theoretical content of 1.1%, thereby obtaining a terminal isocyanate prepolymer; the mixture was cooled to about 50 ° C, 614 g of acetone was added, and the mixture was mixed and dissolved for 5 min, and then 1 g of AEEA (component f)), 8.4 g of A mixture of (component d)) and 37 g of deionized water was reacted at 45°C for 10 min, and a mixed solution of 1.5 g of silane coupling agent I (component a)) and 6 g of acetone was added, and the reaction was continued for 10 min. The mixture was poured into a dispersion cup, and 455 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by vacuum distillation to obtain an aqueous polyurethane-urea dispersion having a solid content of 49 wt% and an average particle size of 188 nm in the dispersed phase measured by laser coherence method, a pH of 7.3, and an acid value of 0.47 mgKOH / g.

[0128] Example 2

[0129] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 350 g of polyester polyol I (component b)), 35 g of polyester polyol II (component b)), 40 g of isocyanate I (component c)), 4 g of isocyanate II (component c)), 4.5 g of MPEG1200 (component e)), 0.01 g of sodium methoxide (the amount of sodium ions is 10 ppm of the obtained terminal isocyanate prepolymer) and 65 g of acetone were added, and the mixture was reacted at 80° C., and NCO% was measured every 1 h. After 3 h, when the NCO% reached the theoretical content of 1.14%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50° C., 672 g of acetone was added, stirred, and mixed and dissolved for 5 min, and then 2 g of AEEA (component f)), 0.6 g of lysine (component g)), 7.2 g of A mixture of (component d)) and 39 g of deionized water was reacted at 45°C for 10 minutes, and then a mixed solution of 0.9 g of silane coupling agent II (component a)) and 4 g of acetone was added, and the reaction was continued for 10 minutes. The mixture was poured into a dispersion cup, and 499 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by vacuum distillation to obtain an aqueous dispersion of polyurethane-urea having a solid content of 49 wt% and an average particle size of 182 nm in the dispersed phase measured by laser coherence method, a pH of 7.1, and an acid value of 0.22 mgKOH / g.

[0130] Example 3 (compared with Example 2)

[0131] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 350 g of polyester polyol I (component b)), 35 g of polyester polyol II (component b)), 40 g of isocyanate I (component c)), 4 g of isocyanate II (component c)), 4.5 g of MPEG1200 (component e)) and 65 g of acetone were added and reacted at 80° C., and NCO% was measured every 1 h. After 3 h, when NCO% reached the theoretical content of 1.14%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50° C., 672 g of acetone was added and stirred, mixed and dissolved for 5 min, and then 2 g of AEEA (component f)), 0.6 g of lysine (component g)), 7.2 g of A mixture of (component d)) and 39 g of deionized water was reacted at 45°C for 10 minutes, and then a mixed solution of 0.9 g of silane coupling agent II (component a)) and 4 g of acetone was added, and the reaction was continued for 10 minutes. The mixture was poured into a dispersion cup, and 499 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by reduced pressure distillation to obtain an aqueous dispersion of polyurethane-urea having a solid content of 49 wt% and an average particle size of 178 nm in the dispersed phase measured by laser coherence method, a pH of 7.0, and an acid value of 0.2 mgKOH / g.

[0132] Example 4

[0133] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 205g of polyester polyol I (component b)), 205g of polyester polyol II (component b)), 30g of isocyanate I (component c)), 10g of isocyanate II (component c)), 0.2g of MPEG1200 (component e)), and 90g of acetone were added and reacted at 80°C. NCO% was measured every 1h. After 3h, when the NCO% reached the theoretical content of 0.82%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50°C, 765g of acetone was added and stirred, and the mixture was mixed and dissolved for 5min, and then 2g of lysine (component g)) and 7.2g of A mixture of (component d)) and 37 g of deionized water was reacted at 45°C for 10 minutes, and then a mixed solution of 0.3 g of silane coupling agent III (component a)) and 3 g of acetone was added, and the reaction was continued for 10 minutes. The mixture was poured into a dispersion cup, and 521 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by vacuum distillation to obtain an aqueous polyurethane-urea dispersion having a solid content of 49 wt% and an average particle size of 196 nm in the dispersed phase measured by laser coherence method, a pH of 7.3, and an acid value of 1.4 mgKOH / g.

[0134] Example 5

[0135] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 250 g of polyester polyol I (component b)), 100 g of polycaprolactone polyol III (component b)), 50 g of isocyanate I (component c)), 6 g of MPEG1200 (component e)), 6 g of DMPA (component g)) and 41 g of acetone were added and reacted at 80° C., and NCO% was measured every 1 h. After 3 h, when NCO% reached a theoretical content of 1.4%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50° C., 618 g of acetone was added and stirred, mixed and dissolved for 5 min, and then 4 g of IPDA (component f)) and 4.5 g of A mixture of (component d)) and 34 g of deionized water was reacted at 45°C for 10 min, and a mixed solution of 3 g of silane coupling agent I (component a)) and 30 g of acetone was added, and the reaction was continued for 10 min. The mixture was poured into a dispersion cup, and 481 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by reduced pressure distillation to obtain an aqueous polyurethane-urea dispersion having a solid content of 49 wt% and an average particle size of 177 nm in the dispersed phase measured by laser coherence method, a pH of 7.0, and an acid value of 2.7 mgKOH / g.

[0136] Example 6

[0137] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 390 g of polyester polyol II (component b)), 34 g of isocyanate I (component c)), 3 g of isocyanate II (component c)), 1 g of MPEG1200 (component e)), 0.5 g of DMPA (component g)) and 43 g of acetone were added and reacted at 80° C., and NCO% was measured every 1 h. After 3 h, when NCO% reached the theoretical content of 1.46%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50° C., 728 g of acetone was added and stirred, mixed and dissolved for 5 min, and then 5 g of IPDA (component f)) and 10 g of A mixture of (component d)) and 60 g of deionized water was reacted at 45°C for 10 minutes, and then a mixed solution of 2 g of silane coupling agent I (component a)) and 20 g of acetone was added, and the reaction was continued for 10 minutes. The mixture was poured into a dispersion cup, and 478 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by reduced pressure distillation to obtain an aqueous dispersion of polyurethane-urea having a solid content of 49 wt% and an average particle size of 192 nm in the dispersed phase measured by laser coherence method, a pH of 7.3, and an acid value of 0.008 mgKOH / g.

[0138] Example 7

[0139] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 370 g of polyester polyol I (component b)), 50 g of isocyanate I (component c)), 20 g of isocyanate II (component c)), 7 g of MPEG1200 (component e)), 10 g of DMPA (component g)) and 46 g of acetone were added and reacted at 80° C., and NCO% was measured every 1 h. After 3 h, when NCO% reached a theoretical content of 2.09%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50° C., 777 g of acetone was added and stirred, mixed and dissolved for 5 min, and then 10 g of IPDA (component f)) and 4.5 g of A mixture of (component d)) and 58 g of deionized water was reacted at 45°C for 10 min, and a mixed solution of 5 g of silane coupling agent I (component a)) and 20 g of acetone was added, and the reaction was continued for 10 min. The mixture was poured into a dispersion cup, and 522 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by reduced pressure distillation to obtain an aqueous dispersion of polyurethane-urea having a solid content of 49 wt% and an average particle size of 185 nm in the dispersed phase measured by laser coherence method, a pH of 6.9, and an acid value of 4.5 mgKOH / g.

[0140] Example 8

[0141] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 200 g of polyester polyol I (component b)), 150 g of polycarbonate polyol IV (component b)), 40 g of isocyanate I (component c)), 2 g of isocyanate II (component c)), 2.44 g of MPEG1200 (component e)) and 59 g of acetone were added and reacted at 80°C. NCO% was measured every 1 h. After 3 h, when the NCO% reached the theoretical content of 1.32%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50°C, 611 g of acetone was added, stirred, mixed and dissolved for 5 min, and then 1 g of AEEA (component f)), 8.4 g of A mixture of (component d)) and 37 g of deionized water was reacted at 45°C for 10 min, and a mixed solution of 1.5 g of silane coupling agent I (component a)) and 6 g of acetone was added, and the reaction was continued for 10 min. The mixture was poured into a dispersion cup, and 455 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by reduced pressure distillation, and a mixed solution of 1.5 g of lactic acid (component g)) and 10 g of water was added to obtain an aqueous dispersion of polyurethane-urea having a solid content of 49 wt% and an average particle size of 188 nm in the dispersed phase measured by laser coherence method, a pH value of 7.3, and an acid value of 0.66 mgKOH / g.

[0142] Comparative Example 1 (compared with Example 3)

[0143] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 350 g of polyester polyol I (component b)), 35 g of polyester polyol II (component b)), 40 g of isocyanate I (component c)), 4 g of isocyanate II (component c)), 4.5 g of MPEG1200 (component e)) and 65 g of acetone were added and reacted at 80° C., and NCO% was measured every 1 h. After 3 h, when NCO% reached a theoretical content of 1.14%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50° C., 672 g of acetone was added and stirred, and the mixture was mixed and dissolved for 5 min, and then 2 g of AEEA (component f)), 0.2 g of lysine (component g)), 7.2 g of A mixture of (component d)) and 39 g of deionized water was reacted at 45°C for 10 min, and a mixed solution of 0.9 g of silane coupling agent II (component a)) and 4 g of acetone was added, and the reaction was continued for 10 min. The mixture was poured into a dispersion cup, and 499 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by reduced pressure distillation to obtain an aqueous dispersion of polyurethane-urea having a solid content of 49 wt% and an average particle size of 185 nm in the dispersed phase measured by laser coherence method, a pH of 7.2, and an acid value of 0.004 mgKOH / g.

[0144] Comparative Example 2 (compared with Example 7)

[0145] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 370 g of polyester polyol I (component b)), 50 g of isocyanate I (component c)), 20 g of isocyanate II (component c)), 7 g of MPEG1200 (component e)), 13 g of DMPA (component g)) and 46 g of acetone were added and reacted at 80° C., and NCO% was measured every 1 h. After 3 h, when NCO% reached the theoretical content of 1.71%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50° C., 777 g of acetone was added and stirred, mixed and dissolved for 5 min, and then 6 g of IPDA (component f)) and 4.5 g of A mixture of (component d)) and 58 g of deionized water was reacted at 45°C for 10 minutes, and then a mixed solution of 5 g of silane coupling agent I (component a)) and 20 g of acetone was added, and the reaction was continued for 10 minutes. The mixture was poured into a dispersion cup, and 522 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by vacuum distillation to obtain an aqueous dispersion of polyurethane-urea having a solid content of 49 wt% and an average particle size of 177 nm in the dispersed phase measured by laser coherence method, a pH of 7.0, and an acid value of 5.5 mgKOH / g.

[0146] Comparative Example 3 (Compared with Example 3, no silane coupling agent was added)

[0147] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 350 g of polyester polyol I, 35 g of polyester polyol II, 40 g of isocyanate I, 4 g of isocyanate II, 4.5 g of MPEG1200 and 65 g of acetone were added and reacted at 80 ° C. Samples were taken every 1 h to measure NCO%, and after 3 h, the NCO% reached a theoretical content of 1.14%, and the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50 ° C, 672 g of acetone was added and stirred, mixed and dissolved for 5 min, and then 2 g of AEEA, 0.6 g of lysine and 7.2 g of The mixture was reacted with 39 g of deionized water at 45° C. for 20 min, poured into a dispersion cup, and 498 g of water was added under high-speed shearing conditions of 1500 rpm. The acetone was then removed by vacuum distillation to obtain an aqueous dispersion of polyurethane-urea having a solid content of 49 wt % and an average particle size of 191 nm measured in the dispersed phase by laser coherence method, a pH of 7.2, and an acid value of 0.22 mgKOH / g.

[0148] Comparative Example 4 (Compared with Example 3, the amount of silane coupling agent used is less)

[0149] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 350 g of polyester polyol I, 35 g of polyester polyol II, 40 g of isocyanate I, 4 g of isocyanate II, 4.5 g of MPEG1200 and 65 g of acetone were added and reacted at 80 ° C. Samples were taken every 1 h to measure NCO%, and after 3 h, the NCO% reached a theoretical content of 1.14%, and the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50 ° C, 672 g of acetone was added and stirred, mixed and dissolved for 5 min, and then 2 g of AEEA, 0.6 g of lysine and 7.2 g of The mixture was reacted with 39 g of deionized water at 45° C. for 10 min, and then a mixed solution of 0.1 g of silane coupling agent II and 2 g of acetone was added. The reaction was continued for 10 min, and the mixture was poured into a dispersion cup. 498 g of water was added under high-speed shear conditions of 1500 rpm, and then the acetone was removed by vacuum distillation to obtain an aqueous dispersion of polyurethane-urea. The dispersion had a solid content of 49 wt % and an average particle size of 201 nm in the dispersed phase measured by laser coherence method, a pH value of 7.3, and an acid value of 0.2 mg KOH / g.

[0150] Comparative Example 5 (Compared with Example 6, the amount of silane coupling agent used is too high)

[0151] To a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer, 390 g of polyester polyol II (component b)), 34 g of isocyanate I (component c)), 3 g of isocyanate II (component c)), 1 g of MPEG1200 (component e)), 0.5 g of DMPA (component g)) and 43 g of acetone were added and reacted at 80° C., and NCO% was measured every 1 h. After 3 h, when NCO% reached the theoretical content of 1.46%, the reaction was stopped to obtain a terminal isocyanate prepolymer; the temperature was lowered to about 50° C., 728 g of acetone was added and stirred, mixed and dissolved for 5 min, and then 2.4 g of IPDA (component f)) and 10 g of A mixture of (component d)) and 60 g of deionized water was reacted at 45°C for 10 minutes, and then a mixed solution of 6.2 g of silane coupling agent I (component a)) and 20 g of acetone was added, and the reaction was continued for 10 minutes. The mixture was poured into a dispersion cup, and 478 g of water was added under high-speed shear conditions of 1500 rpm. The acetone was then removed by vacuum distillation to obtain an aqueous dispersion of polyurethane-urea having a solid content of 49 wt% and an average particle size of 201 nm in the dispersed phase measured by laser coherence method, a pH of 7.5, and an acid value of 0.01 mgKOH / g.

[0152] Test method description:

[0153] (1) Test of initial adhesion and heat and humidity resistance:

[0154] (1) Preparation of adhesive samples to be tested:

[0155] 100 g of each dispersion sample prepared in each Example and Comparative Examples 1-5 was taken, 0.05 g of defoamer (BYK024), 0.2 g of wetting agent (Tego 245), and 0.15 g of thickener (Vesmody U604) were added, and stirred evenly. The mixture was used as an adhesive test sample.

[0156] (2) Preparation of test specimens:

[0157] Pretreatment of black rubber strips: After grinding a 60 mm × 20 mm black rubber strip with a grinder, wipe it clean with butanone, then wipe it four times with a 2 wt% trichloroisocyanurate in acetone solution (oily bismuth powder), bake it in a 70°C oven for 2 minutes, remove it, and let it cool for later use.

[0158] Pretreatment of white rubber strips: Polish a 60 mm x 20 mm piece of white rubber with a grinder, wipe it clean with butanone, then wipe it four times with a 2 wt% trichloroisocyanurate in acetone solution (oily bismuth powder), bake it in a 70°C oven for 2 minutes, remove it, and let it cool before use.

[0159] Pretreatment of white canvas: Cut the white canvas into 70mm×20mm strips, evenly apply the adhesive sample to be tested on the canvas, place it in a 65℃ oven for 6 minutes, take it out and let it cool for use.

[0160] (3) Performance testing:

[0161] Initial Tack: Use a brush to gently brush the adhesive sample prepared from the dispersions in each example and comparative example onto two pretreated black rubber strips, brushing back and forth three times. Then, place both black rubber strips in a 65°C oven and dry for 3 minutes. Then, remove them from the oven. Fold the two black rubber strips into an arc shape and gently place them perpendicular to each other. Then, pull them apart. Score the tack based on the force required to pull them apart. (Tack is scored from low to high: A, A+, A++, A+++, A++++).

[0162] Resistance to moisture and heat: The adhesive samples prepared from the dispersions of the embodiments and comparative examples were evenly applied on pretreated white rubber strips and white canvas, respectively, and activated in an oven at 65°C for 3 min. The strips were taken out and pressed together using a press (20 kgf × 3 s). The bonded strips were placed in a constant temperature and humidity room for 24 h. After 24 h, the strips were hung in a constant temperature and humidity box with a temperature of 70°C and a humidity of 95%. A weight of 1 kg was placed on the white canvas side of the bonded strips, and the time it took for the white canvas and white rubber to be completely peeled off was recorded.

[0163] (2) 70℃×4 days heat and humidity resistance test:

[0164] The test was conducted according to the moisture and heat resistance test method in "(I) Testing of Initial Tack and Moisture and Heat Resistance", except that the adhesive sample to be tested was prepared as follows: 100 g of each dispersion sample prepared in each Example and Comparative Example was sealed and placed in a 70°C oven for 4 days. The sample was then removed and allowed to return to room temperature. 0.05 g of defoamer (BYK024), 0.2 g of wetting agent (Tego 245), and 0.15 g of thickener (Vesmody U604) were then added and stirred until uniformly mixed. The mixture was then used as the adhesive sample to be tested.

[0165] Performance comparison between examples and comparative examples

[0166] As can be seen from the above table, compared with Comparative Examples 1-5, the dispersion obtained in the Examples of the present invention is used as a main component as an adhesive, has better resistance to moisture and heat and hydrolysis, while also having good initial adhesion, and has greater practical application value.

[0167] Compared with the examples, Comparative Examples 1 and 2 failed to control the acid value of the dispersion to between 0.005 mgKOH / g and 5 mgKOH / g, failing to achieve both good resistance to moisture and heat and hydrolysis resistance. Compared with the examples, Comparative Example 3 failed to use a silane coupling agent, failing to achieve both good resistance to moisture and heat and hydrolysis resistance. Compared with the examples, Comparative Examples 4 and 5 failed to use a silane coupling agent in an amount that did not meet the requirements of the present invention, failing to achieve both good resistance to moisture and heat, hydrolysis resistance, and initial tack.

[0168] It will be readily understood that the above embodiments are merely examples for clarity of description and are not intended to limit the present invention to these examples. Those skilled in the art will readily appreciate that other variations or modifications based on the above description are possible. It is not necessary and impossible to provide an exhaustive list of all possible implementations. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. An aqueous dispersion of polyurethane or polyurethane urea, characterized in that, Prepared by reacting a composition comprising the following components: a) At least one siloxane compound, the general formula of the siloxane compound being wherein the group R contains at least one NCO-reactive group, and at least two of the groups R1, R2 and R3 are the same or different alkoxy groups selected from methoxy or ethoxy; b) At least one polyol having a functionality of 2-4; c) At least one polyisocyanate; d) At least one hydrophilic compound, and the hydrophilic group of the hydrophilic compound comprises one or more of ionic groups or latent ionic groups, and the hydrophilic compound contains 2-3 NCO-reactive groups; e) At least one monofunctional non-ionic hydrophilic compound reactive with NCO; Optional component f): At least one compound containing 1-3 amino groups and no COOH group; Optionally, the raw materials for preparing the aqueous dispersion further include an optional component g): At least one compound containing a COOH group and simultaneously containing 1-3 amino groups or hydroxyl groups; Based on the total mass of the components a)-g), the amounts of each component are as follows: component a) 0.05-1.25 wt%, component b) 75-92 wt%, component c) 7-17 wt%, component d) 0.5-2.5 wt%, component e) 0.02-1.5 wt%, component f) 0-2.5 wt%, component g) 0-3 wt%; And, the acid value of the aqueous dispersion is between 0.005 mg KOH / g and 5 mg KOH / g, preferably between 0.01 mg KOH / g and 3 mg KOH / g, more preferably between 0.02 mg KOH / g and 3 mg KOH / g.

2. The aqueous dispersion according to claim 1, wherein, In the process of preparing the aqueous dispersion, the prepolymer of terminal isocyanate is prepared in the presence of trace alkali metal ions, and based on 100% of the total mass of the prepolymer of terminal isocyanate, the content of the alkali metal ions is 0.1 ppm - 30 ppm, preferably 0.1 - 23 ppm, and the alkali metal ions are selected from Na + and / or K + ; The prepolymer of the terminal isocyanate is obtained by reacting raw materials comprising at least component b), component c) and component e).

3. The aqueous dispersion according to any one of claims 1-2, characterized in that, In the component a), the NCO-reactive group in the group R is selected from one or more of hydroxyl group, primary amino group and secondary amino group; preferably, the component a) has at least one primary amino group or secondary amino group; preferably, the group R is a saturated fatty alkyl chain having at least one primary amino group and / or secondary amino group, and optionally having an alkoxy group; Preferably, the component a) is selected from one or more of bis(3-trimethoxysilylpropyl)amine, bis(3-triethoxysilylpropyl)amine, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldiethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane.

4. The aqueous dispersion according to any one of claims 1-3, characterized in that, In the component b), the number average molecular weight of the polyol is 500-10000, preferably 1000-5000, more preferably 1000-4000; Preferably, the polyol is selected from one or more of diols, triols and tetraols; More preferably, the polyol is selected from one or more of polyadipic acid series polyester polyols, polycaprolactone polyols and polycarbonate polyols; More preferably, the polyol is selected from poly(hexamethylene adipate) polyester diols with a functionality of 2 and a number average molecular weight of 1000 to 4000.

5. The aqueous dispersion according to any one of claims 1 - 4, characterized in that, In the component c), the polyisocyanate is selected from one or more of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,4-diisocyanato-cyclohexane, isophorone diisocyanate, 4,4'-diisocyanato-dicyclohexyl-methane, 4,4'-diisocyanato-2,2-dicyclohexylpropane, 1,4-diisocyanatobenzene, 2,4-diisocyanatotoluene, 2,6-diisocyanatotoluene, 4,4'-diisocyanato-diphenylmethane, 2,2'-diisocyanatodiphenylmethane, 2,4'-diisocyanatodiphenylmethane, tetramethylxylylene diisocyanate, p-xylylene diisocyanate, p-isopropylidene diisocyanate, p-phenylene diisocyanate, and cyclohexane dimethylene diisocyanate; preferably hexamethylene diisocyanate and / or isophorone diisocyanate.

6. The aqueous dispersion according to any one of claims 1-5, characterized in that, In the component d), the hydrophilic compound is selected from one or more of N-(2-aminoethyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-2-aminoethanesulfonic acid, N-(3-aminopropyl)-3-aminopropanesulfonic acid, N-(2-aminoethyl)-3-aminopropanesulfonic acid, and their alkali metal salts, alkaline earth metal salts, and ammonium salts; preferably N-(2-aminoethyl)-2-aminoethanesulfonate.

7. The aqueous dispersion according to any one of claims 1-6, characterized in that, In the component e), the number average molecular weight of the nonionic hydrophilic compound is 200 - 8000, preferably 500 - 3000; Preferably, the number of ethylene oxide units in the nonionic hydrophilic compound is 4 - 200, more preferably 12 - 75; Preferably, the nonionic hydrophilic compound is a monofunctional polyethoxy ether with a number average molecular weight of 200 - 8000 and 4 - 200 ethylene oxide units, more preferably polyethylene glycol monomethyl ether with a number average molecular weight of 500 - 3000 and 12 - 75 ethylene oxide units.

8. The aqueous dispersion according to any one of claims 1-7, characterized in that, In the component f), the compound containing 1 - 3 amino groups and no COOH groups is one or more of aliphatic amine compounds and alicyclic amine compounds. Preferably, the amino groups contained therein are primary amine groups and / or secondary amine groups. Optionally, the compound containing 1 - 3 amino groups and no COOH groups contains hydroxyl groups; Preferably, the component f) is selected from one or two of isophorone diamine and N-(2-hydroxyethyl)ethylenediamine.

9. The aqueous dispersion according to any one of claims 1-8, characterized in that, The raw materials for preparing the aqueous dispersion include the component g), and the component g) is preferably selected from one or more of monohydroxycarboxylic acids, dihydroxycarboxylic acids, dihydroxydicarboxylic acids, trihydroxycarboxylic acids, monoaminocarboxylic acids, diamino-carboxylic acids, and triaminocarboxylic acids; Preferably, the component g) is selected from dimethylolpropionic acid, dimethylolbutyric acid, dimethylolacetic acid, One or more of dihydroxysuccinic acid, hydroxypivalic acid, glycolic acid, hydroxypropionic acid, lysine, lactic acid, 6 - aminocaproic acid, alanine, N-(2 - aminoethyl)-β - alanine, undecanoic acid, 8 - aminocaprylic acid, 5 - aminovaleric acid, 4 - aminobutyric acid, aminobenzoic acid, 4 - aminomethylcyclohexanecarboxylic acid, 2 - aminocaproic acid, 4 - aminocyclohexanecarboxylic acid, 12 - aminododecanoic acid, and 9 - aminononanoic acid, more preferably one or more of dimethylolpropionic acid, lactic acid, and lysine.

10. A method for preparing an aqueous dispersion of a polyurethane or polyurethaneurea according to any one of claims 1-9, characterized in that, The method comprises the following steps: S1: Reacting component b), component c), and component e) to form a prepolymer with terminal isocyanate; S2: After dissolution, continuously reacting the prepolymer with component d), component a), and optionally component f), and then dispersing with water; In step S1 and / or step S2, a solvent that can be partially or completely removed during or by distillation after dispersion is optionally used; The optional component g) is added at any stage of step S1 and / or step S2; Meanwhile, during the preparation of the aqueous dispersion, the acid value of the obtained aqueous dispersion is controlled to be between 0.005 mg KOH / g and 5 mg KOH / g, preferably between 0.01 mg KOH / g and 3 mg KOH / g, more preferably between 0.02 mg KOH / g and 3 mg KOH / g.

11. The method according to claim 10, wherein In step S1, the preparation of the prepolymer of the terminal isocyanate is carried out in the presence of trace alkali metal ions, and based on the total mass of the prepolymer of the terminal isocyanate being 100%, the content of the alkali metal ions is 0.1 ppm - 30 ppm, and the alkali metal ions are selected from Na + and / or K + .

12. The aqueous dispersion according to any one of claims 1 - 9 or the aqueous dispersion prepared by the method according to any one of claims 10 - 11 is used in the preparation of adhesives and sealants.

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