阅读说明：本技术 水性聚氨酯分散体 (Aqueous polyurethane dispersions ) 是由 范志荣 唐世锋 储芸 郑曙光 于 2019-09-30 设计创作，主要内容包括：本发明涉及一种水性聚氨酯分散体、其制备方法、包含其的产品及其用于涂覆组合物、含浸组合物、粘合剂或密封剂的用途。该水性聚氨酯分散体包含由包括以下组分的体系反应得到的聚氨酯：A1)至少一异氰酸酯官能度不小于2的多异氰酸酯；A2)至少两种不同的聚四亚甲基醚二醇A2a)和A2b),所述A2a)的数均分子量为不大于1500g/mol,所述A2b)的数均分子量为大于1500g/mol；和A3)至少一数均分子量为32g/mol-400g/mol的具有羟基和羧基官能的阴离子或潜在阴离子亲水剂；B)至少一具有氨基官能的阴离子或潜在阴离子亲水剂；和C)至少一数均分子量为32g/mol-400g/mol的不具有亲水基团的氨基官能化合物；其中所述A2a)的数均分子量与所述A2b)的数均分子量的比为1∶9-4∶1,所述A3)的重量占所述体系的亲水剂的重量的20％-70％。(The present invention relates to an aqueous polyurethane dispersion, a process for its preparation, products comprising it and their use for coating compositions, impregnating compositions, adhesives or sealants. The aqueous polyurethane dispersion comprises a polyurethane obtained by reacting a system comprising: A1) at least one polyisocyanate having an isocyanate functionality of not less than 2; A2) at least two different polytetramethylene ether glycols A2a) and A2b), the A2a) having a number average molecular weight of not more than 1500g/mol and the A2b) having a number average molecular weight of more than 1500 g/mol; and A3) at least one anionic or potentially anionic hydrophilicizing agent having hydroxyl and carboxyl functions, with a number-average molecular weight of 32g/mol to 400 g/mol; B) at least one anionic or potentially anionic hydrophilising agent having an amino function; and C) at least one amino-functional compound having no hydrophilic groups and a number-average molecular weight of 32g/mol to 400 g/mol; wherein the ratio of the number average molecular weight of the A2a) to the number average molecular weight of the A2b) is 1: 9 to 4: 1, and the weight of the A3) accounts for 20 to 70 percent of the weight of the hydrophilic agent of the system.)

1. An aqueous polyurethane dispersion comprising a polyurethane obtained from the reaction of a system comprising:

A1) at least one polyisocyanate having an isocyanate functionality of not less than 2;

A2) at least two different polytetramethylene ether glycols A2a) and A2b), the A2a) having a number average molecular weight of not more than 1500g/mol and the A2b) having a number average molecular weight of more than 1500 g/mol; and

A3) at least one anionic or potentially anionic hydrophilicizing agent having hydroxyl and carboxyl functions, having a number-average molecular weight of from 32g/mol to 400 g/mol;

B) at least one anionic or potentially anionic hydrophilising agent having an amino function;

C) at least one amino-functional compound having no hydrophilic groups and having a number average molecular weight of 32g/mol to 400 g/mol; and

D) optionally a neutralizing agent;

wherein the ratio of the number average molecular weight of the A2a) to the number average molecular weight of the A2b) is from 1: 9 to 4: 1, and the weight of the A3) anionic or potentially anionic hydrophilizing agent having hydroxyl and carboxyl functions is from 20% to 70% of the weight of hydrophilizing agent of the system, with a number average molecular weight of from 32g/mol to 400 g/mol.

2. A dispersion according to claim 1, characterized in that said a1) polyisocyanate is one or more of the following: aliphatic polyisocyanates and cycloaliphatic polyisocyanates.

3. Dispersion according to claim 1 or 2, characterized in that the a1) polyisocyanate is one or more of the following: hexamethylene diisocyanate and isophorone diisocyanate.

4. A dispersion according to any one of claims 1 to 3, characterised in that the number average molecular weight of A2a) is 400g/mol to 1500g/mol, preferably 600g/mol to 1200g/mol, most preferably 1000 g/mol.

5. Dispersion according to any one of claims 1 to 4, characterised in that the number average molecular weight of A2b) is greater than 1500g/mol and equal to or less than 8000g/mol, preferably 1800g/mol to 4000g/mol, most preferably 2000g/mol to 4000 g/mol.

6. Dispersion according to any one of claims 1 to 5, characterised in that A3) the anionic or potentially anionic hydrophilicizing agent having hydroxyl and carboxyl functions, with a number average molecular weight of 32g/mol to 400g/mol, is dimethylolpropionic acid.

7. The dispersion as claimed in any of claims 1 to 6, wherein the ratio of the number-average molecular weight of A2a) to the number-average molecular weight of A2b) is from 1: 4 to 7: 3.

8. A dispersion according to any one of claims 1 to 7, characterised in that the A3) weight proportion of anionic or potentially anionic hydrophilising agents having hydroxyl and carboxyl functions with a number average molecular weight of 32g/mol to 400g/mol is between 20% and 60%, preferably between 20% and 35%, most preferably between 20% and 30% of the weight proportion of hydrophilising agents of the system.

9. A dispersion according to any one of claims 1 to 8, characterised in that the B) anionic or potentially anionic hydrophilising agent with amino function is sodium 2- [ (2-aminoethyl) amino ] ethanesulfonate.

10. Dispersion according to any one of claims 1 to 9, characterised in that the molar amount of D) neutralising agent is less than or equal to 50 mol%, preferably less than or equal to 30 mol%, based on 100 mol% of the molar amount of a3) anionic or potentially anionic hydrophilising agent having hydroxyl and carboxyl groups with a number average molecular weight of 32g/mol to 400 g/mol.

11. A process for preparing an aqueous polyurethane dispersion according to any one of claims 1 to 10, comprising the steps of:

I) reacting A1) at least one polyisocyanate having an isocyanate functionality of not less than 2; A2) at least two different polytetramethylene ether glycols A2a) and A2b), the A2a) having a number average molecular weight of not more than 1500g/mol and the A2b) having a number average molecular weight of more than 1500 g/mol; and A3) at least one anionic or potentially anionic hydrophilicizing agent having hydroxyl and carboxyl functions, with a number-average molecular weight of 32g/mol to 400g/mol, are mixed and reacted to obtain an isocyanate-functional prepolymer;

II) reacting the isocyanate functional prepolymer, B) at least one anionic or potentially anionic hydrophilising agent having an amino function, C) at least one amino functional compound having a number average molecular weight of from 32g/mol to 400g/mol and not having hydrophilic groups, and D) optionally a neutralising agent to obtain a polyurethane; and

III) introducing water before, during or after step II) to obtain the aqueous polyurethane dispersion.

12. A product comprising the aqueous polyurethane dispersion according to any one of claims 1 to 10.

13. The product according to claim 12, characterized in that it is selected from coating compositions, impregnating compositions, adhesives and sealants.

14. Use of the aqueous polyurethane dispersion according to any one of claims 1 to 10 for coating compositions, impregnating compositions, adhesives or sealants.

15. Use of the aqueous polyurethane dispersion according to any one of claims 1 to 10 for coating compositions, impregnating compositions, adhesives or sealants on fiber-based substrates.

16. An article comprising a substrate prepared, coated, impregnated, bonded or sealed with the aqueous polyurethane dispersion of any of claims 1-10.

17. The article of claim 16, wherein the substrate is fiber-based.

18. The article according to claim 16, characterized in that it is synthetic leather, preferably microfibre synthetic leather.

Technical Field

The present invention relates to an aqueous polyurethane dispersion, a process for its preparation, products comprising it and their use for coating compositions, impregnating compositions, adhesives or sealants, and articles comprising substrates prepared, coated, impregnated, bonded or sealed therewith.

Background

The aqueous polyurethane dispersoid is a polyurethane system taking water as a dispersion medium, has the characteristics of no pollution, safety, reliability, excellent mechanical property and the like, is an important direction of the development of polyurethane industry, and can be widely applied to the fields of coatings, adhesives, fabric coatings, fabric finishing agents, leather finishing agents, paper surface treating agents and the like.

Aqueous polyurethane dispersions are often used for the coating of textile supports and synthetic leather because of their good low temperature flexibility and elasticity. It is particularly important in this case that the dispersions have as low a tendency to hydrolysis as possible and good mechanical strength. In the application field of synthetic leather, especially superfine fiber synthetic leather, the membrane formed by the dispersion is required to have good tolerance performance in acid-base environment. Although aqueous polyurethane dispersions have a wide range of tailorable properties, it is not always possible to produce products with desirable performance characteristics. The film formed by the existing aqueous polyurethane dispersion has the defect that the film cannot simultaneously meet the requirements of better mechanical property and acid and alkali resistance.

WO07022885 discloses elastomeric polyurethane dispersions built from polyester polyols with a high proportion of ethylene glycol and/or diethylene glycol. However, due to the instability of ester bonds, the product is not stable to hydrolysis, and the acid and alkali resistance of the film formed by the dispersion is poor.

DE10122444 discloses aqueous polyurethane dispersions based on polycarbonate and polytetramethylene glycol-based polymer polyols, which exhibit high elasticity, but give films with a low modulus and poor mechanical properties.

WO06075144 discloses polyurethane solutions constructed from diisocyanates, polytetramethylene glycol polyether polyols and polyimines, which form films exhibiting high elasticity. However, the product is a solvent-borne polyurethane and is not an environmentally friendly product.

WO2010142393 describes aqueous polyurethane dispersions built from diisocyanates, polytetramethylene glycol polyether polyols, which give films exhibiting very good elasticity and resilience, and unsatisfactory resistance to acids and bases.

EP2356163 discloses aqueous, carboxylic acid-based modified polyester polyol-based polyurethane dispersions which can be crosslinked with carbodiimides and exhibit good adhesion properties, but are poor in hydrolysis resistance and also are not ideal in acid and alkali resistance.

EP3502156a1 discloses an adhesive comprising an amorphous aqueous polyurethane dispersion and a carbodiimide capable of crosslinking therewith, the aqueous polyurethane dispersion being obtained by reacting components such as an aliphatic polyisocyanate, a polyether polyol, an amino-functional chain extender, a hydrophilic agent, the polyurethane in the aqueous polyurethane dispersion comprising carboxylic acid groups or carboxylate groups.

Therefore, there is a need in the industry, particularly in the textile industry, for example in the field of microfiber synthetic leather, for an aqueous polyurethane dispersion that forms a film having good mechanical properties and acid and alkali resistance.

Disclosure of Invention

The term "cure" refers to the process from a liquid state to a cured state.

The term "adhesive" refers to a mixture comprising chemical components that are curable and adhesive, also used as synonyms for adhesives and/or sealants and/or stickers.

The term "polyurethane" refers to polyurethaneurea and/or polyurethane polyurea and/or polythiourethane.

The term "impregnation" means that a liquid penetrates into a flexible absorbent body, which may be an absorbent body made of polyvinyl chloride, polyvinylidene chloride, nylon, polypropylene, polyester, cellulose, polyacrylamide, polyurethane, or the like.

The object of the present invention is to provide an aqueous polyurethane dispersion, a process for its preparation, products comprising it and their use for coating compositions, impregnating compositions, adhesives or sealants, and articles containing substrates prepared, coated, impregnated, bonded or sealed with it.

An aqueous polyurethane dispersion according to the present invention comprises a polyurethane obtained by reacting a system comprising:

A1) at least one polyisocyanate having an isocyanate functionality of not less than 2;

A2) at least two different polytetramethylene ether glycols A2a) and A2b), the A2a) having a number average molecular weight of not more than 1500g/mol and the A2b) having a number average molecular weight of more than 1500 g/mol; and

A3) at least one anionic or potentially anionic hydrophilicizing agent having hydroxyl and carboxyl functions, having a number-average molecular weight of from 32g/mol to 400 g/mol;

B) at least one anionic or potentially anionic hydrophilising agent having an amino function;

C) at least one amino-functional compound having no hydrophilic groups and having a number average molecular weight of 32g/mol to 400 g/mol; and

D) optionally a neutralizing agent;

wherein the ratio of the number average molecular weight of the A2a) to the number average molecular weight of the A2b) is 1: 9-4: 1, said a3) having a number average molecular weight of 32g/mol to 400g/mol, the weight of the anionic or potentially anionic hydrophilizing agent having hydroxyl and carboxyl functions being 20% to 70% of the weight of the hydrophilizing agent of the system.

According to one aspect of the present invention, there is provided a process for preparing an aqueous polyurethane dispersion provided according to the present invention, comprising the steps of:

I) al) at least one polyisocyanate having an isocyanate functionality of not less than 2; A2) at least two different polytetramethylene ether glycols A2a) and A2b), the A2a) having a number average molecular weight of not more than 1500g/mol and the A2b) having a number average molecular weight of more than 1500 g/mol; and A3) at least one anionic or potentially anionic hydrophilicizing agent having hydroxyl and carboxyl functions, with a number-average molecular weight of 32g/mol to 400g/mol, are mixed and reacted to obtain an isocyanate-functional prepolymer;

II) reacting the isocyanate functional prepolymer, B) at least one anionic or potentially anionic hydrophilising agent having an amino function, C) at least one amino functional compound having a number average molecular weight of from 32g/mol to 400g/mol and not having hydrophilic groups, and D) optionally a neutralising agent to obtain a polyurethane; and

III) introducing water before, during or after step II) to obtain the aqueous polyurethane dispersion.

According to one aspect of the present invention, there is provided a product comprising an aqueous polyurethane dispersion provided according to the present invention.

According to one aspect of the present invention, there is provided the use of the aqueous polyurethane dispersion provided according to the present invention for a coating composition, an impregnating composition, an adhesive or a sealant.

According to one aspect of the present invention, there is provided the use of the aqueous polyurethane dispersion provided according to the present invention for coating compositions, impregnating compositions, adhesives or sealants on fibre-based substrates.

According to one aspect of the present invention, there is provided an article comprising a substrate prepared, coated, impregnated, bonded or sealed with an aqueous polyurethane dispersion provided according to the present invention.

The aqueous polyurethane dispersion is prepared by reacting a system containing two different polytetramethylene ether glycols and two different hydrophilic agents, and a film prepared from a product containing the aqueous polyurethane dispersion has good mechanical properties and acid and alkali resistance. The aqueous polyurethane dispersion is particularly suitable for the harsh conditions of the superfine fiber impregnation process: hot alkaline conditions for the opening process and hot acid conditions for the dyeing process (pH < 6).

Detailed Description

The invention provides an aqueous polyurethane dispersion, which comprises polyurethane obtained by the reaction of a system comprising the following components: A1) at least one polyisocyanate having an isocyanate functionality of not less than 2; A2) at least two different polytetramethylene ether glycols A2a) and A2b), the A2a) having a number average molecular weight of not more than 1500g/mol and the A2b) having a number average molecular weight of more than 1500 g/mol; and A3) at least one anionic or potentially anionic hydrophilicizing agent having hydroxyl and carboxyl functions, with a number-average molecular weight of 32g/mol to 400 g/mol; B) at least one anionic or potentially anionic hydrophilising agent having an amino function; C) at least one amino-functional compound having no hydrophilic groups and having a number average molecular weight of 32g/mol to 400 g/mol; and D) optionally a neutralizing agent; wherein the ratio of the number average molecular weight of the A2a) to the number average molecular weight of the A2b) is 1: 9-4: 1, said a3) having a number average molecular weight of 32g/mol to 400g/mol, the weight of the anionic or potentially anionic hydrophilizing agent having hydroxyl and carboxyl functions being 20% to 70% of the weight of the hydrophilizing agent of the system. The invention also provides a preparation method of the aqueous polyurethane dispersion, a product containing the aqueous polyurethane dispersion, application of the product containing the aqueous polyurethane dispersion to a coating composition, an impregnated composition, an adhesive or a sealant, and an article containing a substrate prepared, coated, impregnated, bonded or sealed by the aqueous polyurethane dispersion.

A1) Polyisocyanates

The isocyanate functionality of the polyisocyanate is preferably 2 to 4, more preferably 2 to 2.6, even more preferably 2 to 2.4, most preferably 2.

The polyisocyanate is preferably one or more of the following: aliphatic polyisocyanates and cycloaliphatic polyisocyanates, further preferably one or more of the following: 1, 4-butylidene diisocyanate, Hexamethylene Diisocyanate (HDI), isophorone diisocyanate (IPDI), 2, 4-and/or 2,4, 4-trimethyl-hexamethylene diisocyanate, isomeric bis (4,4 '-isocyanatocyclohexyl) methane, 1, 4-cyclohexylidene diisocyanate, 1, 4-phenylene diisocyanate, 2, 4-toluene diisocyanate, 2, 6-toluene diisocyanate, 1, 5-naphthylidene diisocyanate, 2' -diphenylmethane diisocyanate, 2,4 '-diphenylmethane diisocyanate, 4,4' -diphenylmethane diisocyanate, 1, 3-bis (2-isocyanatoprop-2-yl) benzene (TMXDI), 1, 4-bis (2-isocyanatoprop-2-yl) benzene (TMXDI), 1, 3-bis (isocyanatomethyl) benzene (XDI), alkyl-2, 6-diisocyanatohexanoate (lysine diisocyanate) having C1-C8 alkyl groups and their derivatives having uretdione, isocyanurate, carbamate, allophanate, biuret, iminooxadiazinedione and/or oxadiazinetrione structures; most preferably one or more of the following: hexamethylene diisocyanate and isophorone diisocyanate.

The amount of the polyisocyanate is preferably 5% to 40% by weight, more preferably 5% to 35% by weight, most preferably 5% to 30% by weight, based on 100% by weight of the system.

Polytetramethylene ether glycol A2a) and A2b)

The polytetramethylene ether glycols A2a) and A2b) of the invention each independently correspond to the following general formula: (HO- (CH)₂-CH₂-CH₂-CH₂-O)_x-H)。

The polytetramethylene ether glycol (polytetramethylene glycol polyether) can be obtained by, for example, cationic ring-opening polymerization of tetrahydrofuran.

The polytetramethylene ether glycol A2a) preferably has a number average molecular weight of 400g/mol to 1500g/mol, more preferably 600g/mol to 1200g/mol, most preferably 1000 g/mol.

The polytetramethylene ether glycol A2b) preferably has a number average molecular weight of more than 1500g/mol and 8000g/mol or less, more preferably 1800g/mol to 4000g/mol, most preferably 2000 g/mol.

The ratio of the number average molecular weight of the polytetramethylene ether glycol A2a) to the number average molecular weight of the polytetramethylene ether glycol A2b) is 1: 4-7: 3, most preferably 1: 4-1: 1.

the number average molecular weight was determined by gel permeation chromatography in tetrahydrofuran at 23 ℃ against polystyrene standards.

The mass ratio of the polytetramethylene ether glycol A2a) to the polytetramethylene ether glycol A2b) is preferably 1: 15-2: 1, most preferably 1: 10-1: 1.

the amount of the A2) polytetramethylene ether glycol is preferably 55 wt% to 90 wt%, further preferably 60 wt% to 90 wt%, most preferably 65 wt% to 90 wt%, based on 100 wt% of the system.

A3) Anions or latent anions having hydroxyl and carboxyl functions with a number-average molecular weight of 32g/mol to 400g/mol Hydrophilic agent

Said A3) is preferably dimethylolpropionic acid.

The A3) weight proportion of anionic or potentially anionic hydrophilicizing agents having hydroxyl and carboxyl functions, having a number average molecular weight of from 32g/mol to 400g/mol, is preferably from 20% to 60%, more preferably from 20% to 35%, most preferably from 20% to 30% by weight of the hydrophilicizing agents of the system.

A4) Other Polymer polyols

The system may further comprise a polymeric polyol different from A2) the polytetramethylene polyether glycol.

The polymer polyol is preferably one or more of the following: polyester polyols, polyacrylate polyols, polyurethane polyols, polycarbonate polyols, polyether polyols, polyester polyacrylate polyols, polyurethane polyester polyols, polyurethane polyether polyols, polyurethane polycarbonate polyols and polyester polycarbonate polyols.

The content of the polymer polyol based on the A2) polytetramethylene ether glycol is preferably 0 to 20% by weight, more preferably 0 to 15% by weight.

A5) Hydroxy-functional compounds having a number-average molecular weight of 62 to 399g/mol

The system may further comprise a hydroxy-functional compound having a number average molecular weight of 62 to 399 g/mol.

The hydroxy-functional compound having a number average molecular weight of 62 to 399g/mol is preferably one or more of the following: non-polymeric polyols, ester diols and monofunctional isocyanate-reactive hydroxyl containing compounds of no more than 20 carbon atoms.

The non-polymeric polyol having not more than 20 carbon atoms is preferably one or more of the following: ethylene glycol, diethylene glycol, triethylene glycol, 1, 2-propanediol, 1, 3-propanediol, 1, 4-butanediol, 1, 3-butanediol, cyclohexanediol, 1, 4-cyclohexanedimethanol, 1, 6-hexanediol, neopentyl glycol, hydroquinone dihydroxyethyl ether, bisphenol A (2, 2-bis (4-hydroxyphenyl) propane), hydrogenated bisphenol A (2, 2-bis (4-hydroxycyclohexyl) propane), trimethylolpropane, trimethylolethane, glycerol and pentaerythritol.

The ester diol is preferably one or more of the following: α -hydroxybutyl- ε -hydroxyhexanoate, ω -hydroxyhexyl- γ -hydroxybutyrate, adipic acid (. beta. -hydroxyethyl) ester and terephthalic acid di (. beta. -hydroxyethyl) ester.

The monofunctional isocyanate-reactive hydroxyl group containing compound is preferably one or more of the following: ethanol, n-butanol, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monobutyl ether, 2-ethylhexanol, 1-octanol, 1-dodecanol, and 1-hexadecanol.

The amount of the hydroxyl-functional compound having a number average molecular weight of 62 to 399g/mol is preferably 0 to 10% by weight, most preferably 0 to 5% by weight, based on 100% by weight of the solids of the aqueous polyurethane dispersion.

A6) Isocyanate-reactive nonionic hydrophilizing agents

The system may further comprise an isocyanate-reactive nonionic hydrophilising agent.

The isocyanate reactive nonionic hydrophilising agent is preferably one or more of the following: polyoxyalkylene ethers having hydroxyl groups, polyoxyalkylene ethers having amino groups, and polyoxyalkylene ethers having thiol groups.

The isocyanate-reactive nonionic hydrophilicizing agents are most preferably polyalkylene oxide polyether alcohols having a monohydroxy function, the statistical average number of ethylene oxide units per molecule preferably being from 5 to 70, particularly preferably from 7 to 55, which are obtainable in a known manner by alkoxylation of suitable starter molecules (e.g.Ullmanns encyclopedia of Industrial chemistry, fourth edition, volume 19, German chemical Press, Wehnerm, pages 31 to 38) (Ullmanns)der technischen Chemie,4th edition, vol.19, Verlag Chemie, Weinheim pp.31-38). The monohydroxy-functional polyalkylene oxide polyether alcohols preferably have from 40 to 100 mol% of ethylene oxide and from 0 to 60 mol% of propylene oxide units.

The starter molecule is preferably a saturated monoalcohol, a diethylene glycol monoalkyl ether, an unsaturated alcohol, an aromatic alcohol, an araliphatic alcohol, a secondary monoamine and a heterocyclic secondary amine, most preferably a saturated monoalcohol.

The saturated monoalcohol is preferably one or more of the following: methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, the isomeric pentanols, hexanols, octanols, nonanols, n-decanols, n-dodecanols, n-tetradecanols, n-hexadecanols, n-octadecanols, cyclohexanol, the isomeric methylcyclohexanols, hydroxymethylcyclohexane, 3-ethyl-3-hydroxymethyloxetane, tetrahydrofurfuryl alcohol and diethylene glycol monoalkyl ethers, most preferably one or more of the following: n-butanol and diethylene glycol monobutyl ether.

The unsaturated alcohol is preferably one or more of the following: allyl alcohol, 1-dimethylallyl alcohol and oleyl alcohol.

The aromatic alcohol is preferably one or more of the following: phenol, the isomeric cresols and methoxyphenols.

The araliphatic alcohol is preferably one or more of the following: benzyl alcohol, anisol and cinnamyl alcohol.

The secondary monoamine is preferably one or more of the following: dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, bis (2-ethylhexyl) amine, N-methylcyclohexylamine, N-ethylcyclohexylamine and dicyclohexylamine.

The heterocyclic secondary amine is preferably one or more of the following: morpholine, pyrrolidine, piperidine and 1H-pyrazole.

B) Anionic or potentially anionic hydrophilicizing agents having amino functions

The B) anionic or potentially anionic hydrophilicizing agent having an amino function preferably comprises one or more of the following groups: sulfonic acid groups, sulfonate groups, carboxylic acid groups, and carboxylic acid ester groups, most preferably comprising sulfonate groups. The sulfonate group is preferably a sodium sulfonate group.

The B) anionic or potentially anionic hydrophilicizing agents having amino functions are preferably one or more of the following: alkali metal salts of monoamine sulfonic acids, alkali metal salts of diamine sulfonic acids, diamino carboxylic acids and salts of diamino carboxylic acids; further preferred is one or more of the following: a compound containing a sulfonate group and two amino groups as ionic groups, a compound containing a carboxylic acid group and two amino groups as ionic groups, and a compound containing a carboxylate group and two amino groups as ionic groups; further preferred is one or more of the following: 2- [ (2-aminoethyl) amino ] ethanesulfonate, 1, 3-propanediamine-beta-ethanesulfonate, diaminocarboxylate, and 2, 6-diaminocarboxylic acid; also preferred is one or more of the following: 2- [ (2-aminoethyl) amino ] ethanesulfonate, ethylenediamine propylsulfonate, ethylenediamine butylsulfonate, 1, 2-propylenediamine- β -ethanesulfonate, 1, 2-propylenediamine- β -taurate, 1, 3-propylenediamine- β -ethanesulfonate, Cyclohexylaminopropanesulfonate (CAPS), sodium diaminocarboxylate, and 2, 6-diaminohexanoic acid; sodium 2- [ (2-aminoethyl) amino ] ethanesulfonate is most preferred.

C) Amino-functional compounds having a number-average molecular weight of 32g/mol to 400g/mol, which do not have hydrophilic groups

The amino-functional compounds having no hydrophilic groups, having a number average molecular weight of 32g/mol to 400g/mol, are preferably amines having no ionic or ionizing groups.

The amine having no ionic or ionizing group is preferably one or more of the following: organic diamines, organic polyamines, primary and secondary amines, alkanolamines and monofunctional isocyanate-reactive amines.

The organic diamine or organic polyamine is preferably one or more of the following: 1, 2-ethylenediamine, 1, 2-diaminopropane, 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 6-diaminohexane, isophoronediamine, 2, 4-trimethyl-hexamethylenediamine, 2,4, 4-trimethyl-hexamethylenediamine, 2-methylpentamethylenediamine, diethylenetriamine, 4, 4-diaminodicyclohexylmethane, hydrazine hydrate and dimethylethylenediamine.

The primary and secondary amines are preferably one or more of the following: diethanolamine, 3-amino-1-methylaminopropane, 3-amino-1-ethylaminopropane, 3-amino-1-cyclohexylaminopropane and 3-amino-1-methylaminobutane.

The alkanolamine is preferably one or more of the following: n-aminoethylethanolamine, ethanolamine, 3-aminopropanol and neopentanolamine.

The monofunctional isocyanate-reactive amine compound is preferably one or more of the following: methylamine, ethylamine, propylamine, butylamine, octylamine, laurylamine, stearylamine, isononyloxypropylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, N-methylaminopropylamine, diethyl (methyl) aminopropylamine, morpholine, piperidine and suitable substituted derivatives thereof, for example, the monoketimides of amidoamines, diprimary amines or primary/tertiary amines formed from diprimary amines and monocarboxylic acids.

The amine having no ionic or ionizing group is most preferably one or more of the following: 1, 2-ethylenediamine, bis (4-aminocyclohexyl) methane, 1, 4-diaminobutane, isophoronediamine, ethanolamine, diethanolamine and diethylenetriamine.

The weight of said a5) and said C) and preferably 0.5 wt.% to 20 wt.%, further preferably 0.5 wt.% to 15 wt.%, most preferably 0.5 wt.% to 14 wt.%, based on 100 wt.% of the system.

The weight of said a6) and said B) is preferably 0.1 wt% to 25 wt%, further preferably 0.1 wt% to 15 wt%, most preferably 0.1 wt% to 13.5 wt%, based on 100 wt% of the system.

Neutralizing agent

The molar amount of neutralizing agent is preferably less than or equal to 50 mol%, most preferably less than or equal to 30 mol%, based on 100 mol% of the molar amount of A3) anionic or potentially anionic hydrophilizing agent having hydroxyl and carboxyl functions, with a number average molecular weight of 32g/mol to 400 g/mol.

The neutralising agent is preferably one or more of: ammonia, ammonium carbonate, bicarbonate, trimethylamine, triethylamine, tributylamine, diisopropylethylamine, dimethylethanolamine, diethylethanolamine, triethanolamine, lithium hydroxide, sodium hydroxide, potassium hydroxide, dimethyl sulfate, succinic acid, and sodium carbonate, most preferably one or more of the following: triethylamine, triethanolamine, dimethylethanolamine, sodium hydroxide, potassium hydroxide, diisopropylethylamine, dimethyl sulfate and succinic acid.

Method

The process for preparing the aqueous polyurethane dispersion of the present invention preferably comprises the steps of:

I) al) at least one polyisocyanate having an isocyanate functionality of not less than 2; A2) at least two different polytetramethylene ether glycols A2a) and A2b), the A2a) having a number average molecular weight of not more than 1500g/mol and the A2b) having a number average molecular weight of more than 1500 g/mol; A3) at least one anionic or potentially anionic hydrophilicizing agent having hydroxyl and carboxyl functions, having a number-average molecular weight of from 32g/mol to 400 g/mol; A4) optionally other polymer polyols; A5) optionally a hydroxy-functional compound having a number average molecular weight of 62 to 399 g/mol; and a6) an optional isocyanate-reactive nonionic hydrophilizing agent to obtain an isocyanate-functional prepolymer;

II) reacting the isocyanate functional prepolymer, B) at least one anionic or potentially anionic hydrophilising agent having an amino function, C) at least one amino functional compound having a number average molecular weight of from 32g/mol to 400g/mol and not having hydrophilic groups, and D) optionally a neutralising agent to obtain a polyurethane; and

III) introducing water before, during or after step II) to obtain the aqueous polyurethane dispersion.

The preparation of the aqueous polyurethane dispersions can be carried out in one or more steps, in a homogeneous phase, or in a multistage reaction, partly in the disperse phase. After the polyaddition reaction of Al) to A6) has been completed in whole or in part, a dispersing, emulsifying or dissolving step is preferably carried out. Optionally, a further polyaddition or modification reaction in the dispersed phase is carried out next.

The preparation of the aqueous polyurethane dispersions can be carried out by all methods known from the prior art, such as prepolymer mixing, acetone or melt dispersion, most preferably by the acetone process.

For the preparation by the acetone method, to prepare the isocyanate-functional prepolymer, the components Al) -A6) are generally initially charged in whole or in part and optionally diluted with a water-miscible solvent which is inert toward isocyanate groups and heated to a temperature in the range from 50 ℃ to 120 ℃. To accelerate the isocyanate addition reaction, known catalysts in polyurethane chemistry can be used.

Suitable solvents are the customary aliphatic ketone-functional solvents, such as acetone or 2-butanone, which can be added not only initially but also optionally in part afterwards. Other solvents without isocyanate reactive groups may also be added.

The components of Al) to A6) which have not been added are optionally metered in at the beginning of the reaction.

In the preparation of the isocyanate functional prepolymer of said step I), the molar ratio of isocyanate groups to isocyanate reactive groups is preferably from 1.05 to 3.5, more preferably from 1.1 to 3.0, most preferably from 1.1 to 2.5.

The reaction of the components Al) to A6) of step I) to form the prepolymer may take place partly or completely, but preferably completely. Thus, the isocyanate-functional polyurethane prepolymers containing free isocyanate groups are obtained in bulk as such or in solution. "free" in the context of the present invention includes both free and potentially free.

If the water for dispersion already contains the neutralizing agent, the neutralization can also take place simultaneously with the dispersion.

In a subsequent processing step, if the dissolution of the isocyanate-functional prepolymer has not yet taken place or has taken place only partially, the prepolymer obtained is dissolved with the aid of an aliphatic ketone, such as acetone or 2-butanone.

Said step II) is a chain extension and termination reaction, said B) being an anionic or potentially anionic hydrophilizing agent having an amino function, C) an amino-functional compound having a number average molecular weight of from 32g/mol to 400g/mol and no hydrophilic groups, D) optionally a neutralizing agent, is reacted with the free isocyanate groups of the isocyanate-functional prepolymer obtained in step I.

The degree of chain extension reaction of step II), i.e. the equivalent ratio of isocyanate-reactive groups to free isocyanate groups of the compounds used for the chain extension and termination reactions, is preferably from 40% to 150%, further preferably from 50% to 110%, most preferably from 60% to 100%.

The components B) and C) of step II) can optionally be used in water-or solvent-diluted form, individually or in mixtures, the order of addition being in any order possible in principle. If water or an organic solvent is used as diluent, the amount of diluent is from 40% to 95% by weight of the amount of components used for chain extension in step II).

Said step II) is preferably carried out before water dispersion. For this purpose, the dissolved and chain-extended prepolymer, optionally with the application of strong shear, such as intensive stirring, can be added to the water or, conversely, the water is stirred into the dissolved and chain-extended polyurethane polymer. Water is preferably added to the polyurethane polymer which has been dissolved and chain extended.

The solvent still contained in the dispersion is usually removed by distillation. The solvent may also be removed during the dispersion step.

The residual organic solvent content of the aqueous polyurethane dispersions prepared by the process of the invention is preferably from 0 to 10% by weight, most preferably from 0 to 3% by weight, based on 100% by weight of the aqueous polyurethane dispersion.

The pH of the aqueous polyurethane dispersion is preferably less than 8.0, more preferably less than 7.5, and most preferably from 6.5 to 7.5.

The solids content of the aqueous polyurethane dispersion is preferably from 30% to 55% by weight, based on 100% by weight of the aqueous polyurethane dispersion.

The viscosity of the aqueous polyurethane dispersion is preferably from 15 to 4000 mPa.s.

The particle size of the aqueous polyurethane dispersion is preferably from 50nm to 7000nm, most preferably from 150nm to 7000 nm.

Product(s)

The products are preferably self-coating compositions, impregnating compositions, adhesives and sealants.

The product may comprise a cross-linking agent. The cross-linking agent is preferably one or more of the following: a crosslinking agent having an isocyanate reactive group and a crosslinking agent having a carboxyl reactive group.

The crosslinking agent having an isocyanate reactive group is preferably a hydrophilically modified aliphatic isocyanate crosslinking agent.

The crosslinking agent having a carboxyl-reactive group is preferably a hydrophilically modified carbodiimide.

The product may contain an additive. The additive may be one or more of the following: defoamers, thickeners, thixotropic agents, antioxidants, light stabilizers, emulsifiers, plasticizers, pigments, fillers, skein stabilizing additives, biocides, pH adjusters and flow control agents.

The amount of the additive is preferably 0-15 wt%, most preferably 0.01 wt% to 10 wt%, based on 100 wt% of the product.

Base material

The coating is carried out by applying the aqueous polyurethane dispersion to a substrate, for example by means of a knife, for example a coating knife, roller or other device, or by spraying or dipping.

The coating may be applied on one or both sides of the substrate.

The substrates may be subjected to a surface treatment such as precoating, polishing, napping (velveting), napping (rastering) and/or drum felting drying before, during, or after application of the aqueous polyurethane dispersions of the present invention.

The aqueous polyurethane dispersions of the invention can also be applied to substrates in the form of a multilayer coating.

The substrate is preferably fiber-based, which may be synthetic and/or natural fibers, in principle substrates made from any fiber are suitable for use in the process of the invention.

The fiber-based substrate is preferably a microfiber, most preferably a microfiber nonwoven fabric or microfiber.

The ultrafine fiber may be a sea-island type bicomponent ultrafine fiber. The sea component and the island component of the sea-island type bicomponent superfine fiber are different. The island component of the islands-in-the-sea bicomponent microfiber can be a polymer conventional in textile applications, preferably one or more of the following: ethylene terephthalate, modified polyesters such as poly (trimethylene terephthalate), cationic polyesters, nylons, other types of polyamides, polyethylene, polypropylene, and other types of polyolefins. The sea component of the sea-island type bicomponent superfine fiber may be a polymer that can be dissolved and removed by a treatment means such as water, an aqueous alkali solution or an aqueous acid solution, and preferably one or more of the following: nylon, other polyamides, modified polyesters and other spinnable polymers having basic characteristics of being soluble in water, aqueous acid or aqueous alkali, and the like, and further preferably one or more of the following: alkali water-soluble polyester and hot water-soluble polyvinyl alcohol; most preferably one or more of the following: water-reduced Polyhydroxyalkanoates (PHA) and hot water-soluble polyvinyl alcohols (PVA).

Article of manufacture

The product is preferably synthetic leather, and most preferably superfine fiber synthetic leather.

The articles are preferably suitable for use in outerwear, synthetic leather, shoes, upholstery fabric or car interiors, the above list being by way of example only and not by way of limitation.

The article comprises a film formed by curing the aqueous polyurethane dispersion on the substrate.

The tensile strength at break of the film is preferably not less than 20N/mm²The elongation at break is preferably more than 580%, and the 100% modulus is preferably not less than 2.5N/mm²The swelling ratio is less than 32%.

Examples

Unless defined otherwise, 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. In the event that a definition of a term in this specification conflicts with a meaning commonly understood by those skilled in the art to which the invention pertains, the definition set forth herein shall govern.

Unless otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth herein are approximations that can vary depending upon the desired properties to be obtained.

As used herein, "and/or" means one or all of the referenced elements.

As used herein, "above" and "below" include the numerical values themselves, unless otherwise stated.

As used herein, "comprising" and "comprises" encompass the presence of only the recited elements as well as the presence of other, non-recited elements in addition to the recited elements.

The analytical measurements according to the invention were carried out at 23 ℃ unless otherwise stated.

The percentages of the invention are by weight, unless otherwise indicated.

The solids content of the aqueous polyurethane dispersions was determined using a HS153 moisture meter from Mettler Toledo according to DIN-EN ISO 3251.

The number average molecular weight was determined by gel permeation chromatography in tetrahydrofuran at 23 ℃ against polystyrene standards.

Hydroxyl number was determined according to ASTM D4274.

The isocyanate group (NCO) content is determined volumetrically according to DIN-EN ISO 11909 and the data determined include the free and potentially free NCO content.

The isocyanate group functionality is determined according to GPC.

The particle size of the aqueous polyurethane dispersion was determined using laser spectroscopy (as measured by a Zatasizer Nano ZS 3600 laser particle sizer from Malvern instruments) after dilution with deionized water.

The viscosity of the aqueous polyurethane dispersions was measured at 23 ℃ according to DIN 53019 using a Brookfield DV-II + Pro. rotational viscometer.

The pH of the aqueous polyurethane dispersion was measured at 23 ℃ using a PB-10pH meter from Sartorius, Germany.

Raw materials and reagents

H: 1, 6-hexamethylene diisocyanate, available from Kossi Innovation, Germany.

I: isophorone diisocyanate, available from Kossi Innovation, Germany.

Polytetramethylene ether glycol 1000: hydroxyl number 112mg KOH/g, hydroxyl functionality 2, number average molecular weight 1000g/mol, from Pasteur, Germany.

Polytetramethylene ether glycol 2000: hydroxyl number 56mg KOH/g, hydroxyl functionality 2, number average molecular weight 2000g/mol, from Pasteur, Germany.

Polytetramethylene ether glycol 4000: hydroxyl number 28mg KOH/g, hydroxyl functionality 2, number average molecular weight 4000g/mol, from Pasteur, Germany.

Polycarbonate polyol 1: polycarbonate polyols of hexanediol and dimethyl carbonate with a hydroxyl number of 56mg KOH/g and a number average molecular weight of 2000g/mol were obtained from Korsakow, Germany.

Polycarbonate polyol 2: pentanediol A polycarbonate polyol of hexanediol (molar ratio 55: 45) and dimethyl carbonate, OH number 56mg KOH/g, number average molecular weight 2000g/mol, purchased from Kowski GmbH, Germany.

Polyether polyol 1: propylene oxide-based polyether polyols having a functionality of 2 and a number average molecular weight of 2000g/mol were obtained from Kokson GmbH, Germany.

Polyether polyol 2: monofunctional polyether polyols based on ethylene oxide/propylene oxide, number average molecular weight 2250g/mol, were obtained from Kokson GmbH, Germany.

Polyether polyol 3: LP112, a propylene oxide-based polyether polyol having a functionality of 2 and a number average molecular weight of 1000g/mol, was purchased from Kowski, Inc., Germany.

Dimethylolpropionic acid: purchased from Aldrich chemical agents, germany.

2- [ (2-aminoethyl) amino group]Sodium ethanesulfonate solution: NH (NH)₂-CH₂CH₂-NH-CH₂CH₂-SO₃Na, 45% concentration in water, was purchased from Kossingchun GmbH, Germany.

Ethylene diamine: purchased from Jiaxing jinyan chemical Co., Ltd, China.

Isophorone diamine: purchased from scientific creative gmbh, germany.

2794: a hydrophilically modified blocked aliphatic isocyanate crosslinking agent having a solids content of 38% by weight, an isocyanate group content of 12.7% by weight (based on the solids content), and a viscosity<1500mpa.s, available from kossi, inc.

2802: a hydrophilically modified carbodiimide crosslinker, 40% by weight solids content, 4.2% by weight NCN group content, was purchased from Kossi Injews Co.

Sodium diaminocarboxylate solution: NH (NH)₂-CH₂CH₂-NH-CH₂CH₂-CO₂Na, 40% strength by weight in water, from Pasteur Germany.

Hydrazine hydrate: purchased from Aldrich chemical agents, germany.

Potassium hydroxide: purchased from Sinopharm Chemical Reagent co.ltd., china, and prepared in the laboratory prior to use as a 10% strength aqueous solution.

2, 6-diaminohexanoic acid: 50% solution, available from Xiamen Feihe Chemical Co.Ltd., China.

Sodium hydroxide: analytically pure, purchased from chemical reagents of national drug group, ltd.

Acetic acid: analytically pure, purchased from clin reagent limited.

Preparation of aqueous polyurethane dispersions

Aqueous polyurethane Dispersion 1

1015g of polytetramethylene ether glycol 2000, 217.5g of polytetramethylene ether glycol 1000, 15.6g of dimethylolpropionic acid, 144.4g ofI and 109.3gH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual value of the isocyanate groups (NCO) of the prepolymer is less than or equal to the theoretical value of NCO. The prepolymer was dissolved in 2669.7g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. 12.4g of ethylenediamine and 50.2g of 2- [ (2-aminoethyl) amino group are then metered in]Sodium ethanesulfonate solution and 310.1g of water were stirred for 20 minutes, 1967.3g of water was added for dispersion, and the solvent was removed by vacuum distillation to give an aqueous polyurethane dispersion 1 having a solid content of 41.8% by weight, a viscosity of 159mPa.s (23 ℃ C.), a pH of 6.7 and a particle size of 163.5 nm.

Aqueous polyurethane aqueous dispersion 2

280g of polytetramethylene ether glycol 2000, 60.0g of polytetramethylene ether glycol 1000, 4.3g of dimethylolpropionic acid, 79.7g ofI is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 753.7g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. 3.4g of ethylenediamine and 13.8g of 2- [ (2-aminoethyl) amino group are then metered in]Sodium ethanesulfonate solution and 85.5g of water, stirring for 20 minutes, adding 557.3g of water for dispersion, and removing the solvent by vacuum distillation to obtain an aqueous polyurethane dispersion 2 with a solid content of 41.4 wt% and viscosityA temperature of 15 mPas (23 ℃), a pH value of 6.6 and a particle size of 205.2 nm.

Aqueous polyurethane Dispersion 3

280g of polytetramethylene ether glycol 2000, 60.0g of polytetramethylene ether glycol 1000, 4.3g of dimethylolpropionic acid and 60.3g ofH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 753.7g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. 3.4g of ethylenediamine and 13.8g of 2- [ (2-aminoethyl) amino group are then metered in]Sodium ethanesulfonate solution and 85.5g of water, stirring for 20 minutes, then adding 528.3g of water for dispersion, and vacuum distilling to remove the solvent to obtain aqueous polyurethane dispersion 3, the solid content of which is 42.2% by weight, the viscosity of which is 122.0mPa.s (23 ℃), the pH value of which is 6.8 and the particle size of which is 216.3 nm.

Aqueous polyurethane aqueous Dispersion 4

280g of polytetramethylene ether glycol 2000, 60.0g of polytetramethylene ether glycol 1000, 4.3g of dimethylolpropionic acid, 39.8g ofI and 30.1gH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 753.7g of acetone at 90 ℃ and 0.65g of TEA was added, stirred for 20 minutes and cooled to 40 ℃. 3.4g of ethylenediamine and 13.8g of 2- [ (2-aminoethyl) amino group are then metered in]Sodium ethanesulfonate solution and 85.5g water, stirring for 20 minutes, adding 543.7 g water for dispersion, and vacuum distilling to remove the solvent to obtain aqueous polyurethane dispersion 4 with a solid content of 30.2 wt%, a viscosity of 61mPa.s (23 ℃), a pH value of 7.1 and a particle size of 204.2 nm.

Aqueous polyurethane Dispersion 5

280g of polytetramethylene ether glycol 2000, 60.0g of polytetramethylene ether glycol 1000, 4.3g of dimethylolpropionic acid, 39.8g ofI and 30.1gH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 753.7g of acetone at 90 ℃ and 0.33g of TEA was added, stirred for 20 minutes and then cooled to 40 ℃. 3.4g of ethylenediamine and 13.8g of 2- [ (2-aminoethyl) amino group are then metered in]Sodium ethanesulfonate solution and 85.5g of water, stirring for 20 minutes, then adding 545.1g of water for dispersion, and vacuum distilling to remove the solvent to obtain aqueous polyurethane dispersion 5, the solid content of which is 41.0% by weight, the viscosity of which is 46mPa.s (23 ℃), the pH value of which is 7.0 and the particle size of which is 179.0 nm.

Aqueous polyurethane Dispersion 6

350g of polytetramethylene ether glycol 4000, 37.5g of polytetramethylene ether glycol 1000, 2.7g of dimethylolpropionic acid, 24.9g ofI and 18.8gH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 771.4g of acetone at 90 ℃ and cooled to 40 ℃ after stirring for 20 minutes. 2.1g of ethylenediamine and 8.6g of 2- [ (2-aminoethyl) amino group are then metered in]Sodium ethanesulfonate solution and 53.5g of water were stirred for 20 minutes, 601.7g of water were added thereto for dispersion, and the solvent was removed by vacuum distillation to give aqueous polyurethane dispersion 6 having a solid content of 30.1% by weight, a viscosity of 1960mPa.s (23 ℃), a pH of 7.2 and a particle size of 6066 nm.

Aqueous polyurethane Dispersion 7

23.8g of polycarbonate polyol 1, 291g of polytetramethylene ether glycol 2000,67.5g of polytetramethylene ether glycol 1000, 4.8g of dimethylolpropionic acid, 44.8g ofI and 33.9gH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 828.7g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. Then 3.8g of ethylenediamine and 15.6g of 2- [ (2-aminoethyl) amino group were metered in]Sodium ethanesulfonate solution and 96.2g of water were stirred for 20 minutes, then 610.6g of water was added for dispersion, and the solvent was removed by vacuum distillation to obtain an aqueous polyurethane dispersion 7 having a solid content of 41.4% by weight, a viscosity of 128mPa.s (23 ℃), a pH of 7.0 and a particle size of 178.1 nm.

Aqueous polyurethane aqueous dispersion 8

47.7g of polycarbonate polyol 1, 267.3g of polytetramethylene ether glycol 2000,67.5g of polytetramethylene ether glycol 1000, 4.8g of dimethylolpropionic acid, 44.8g of dimethylolpropionic acidI and 33.9gH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 828.7g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. Then 3.8g of ethylenediamine and 15.6g of 2- [ (2-aminoethyl) amino group were metered in]Sodium ethanesulfonate solution and 96.2g of water were stirred for 20 minutes, then 610.6g of water was added for dispersion, and the solvent was removed by vacuum distillation to obtain an aqueous polyurethane dispersion 8 having a solid content of 41.7% by weight, a viscosity of 40mPa.s (23 ℃), a pH of 6.8 and a particle size of 178.7 nm.

Comparative aqueous polyurethane Dispersion 1

175.5g of polycarbonate polyol 1, 198.6g of polytetramethylene ether glycol 2000, 86.6g of polytetramethylene ether glycol 1000, 16.2g of polyether polyol 2 and 56.69gI and 46.0gH is mixed at 70 ℃, heated to 120 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 1297.62g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. 1.23g of hydrazine hydrate, 11.20g of 2- [ (2-aminoethyl) amino group are then metered in]Sodium ethanesulfonate solution and 30.65g of water were stirred for 20 minutes, then 20.8g of isophoronediamine and 130.59g of water were added, after stirring for 10 minutes at 40 ℃ 255.7g of water were added for dispersion, and the solvent was removed by vacuum distillation to give comparative aqueous polyurethane dispersion 1 having a solids content of 62.9% by weight, a viscosity of 1740mPa.s (23 ℃), a pH of 8.5 and a particle size of 482.7 nm.

Comparative aqueous polyurethane Dispersion 2

238g of polytetramethylene ether glycol 2000, 51.0g of polytetramethylene ether glycol 1000 and 33.9g ofI and 25.6 gH is mixed at 70 ℃, heated to 125 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 619.7g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. 3.4g of ethylenediamine and 11.6g of 2- [ (2-aminoethyl) amino group are then metered in]Sodium ethanesulfonate solution and 77.1g of water were stirred for 20 minutes, 714.3g of water were added for dispersion, and the solvent was removed by vacuum distillation to give comparative aqueous polyurethane dispersion 2 having a solid content of 49.8%, a viscosity of 381mPa.s (23 ℃), a pH of 6.8 and a particle size of 369.5 nm.

Comparative aqueous polyurethane Dispersion 3

1050g of polytetramethylene ether glycol 2000, 225.5g of polytetramethylene ether glycol 1000, 8.1g of dimethylolpropionic acid and 149.4g ofI and 113.1gH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 2747.7g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. 17.1g of ethylenediamine, 51.9g of 2- [ (2-aminoethyl) amino group were then metered in]Sodium ethanesulfonate solution and 361.7g of water were stirred for 20 minutes, 1548.3g of water were added for dispersion, and the solvent was removed by vacuum distillation to give comparative aqueous polyurethane dispersion 3 having a solid content of 46.0% by weight, a viscosity of 994mPa.s (23 ℃), a pH of 7.1 and a particle size of 224.5 nm.

Comparative aqueous polyurethane Dispersion 4

157.5g of polycarbonate polyol 2, 205.6g of polytetramethylene ether glycol 2000, 115.3g of polyether polyol 1, 14.6g of polyether polyol 2 and 50.4g of polyether polyolI and 41.5gH is mixed at 70 ℃, heated to 120 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 1167.7g of acetone at 90 ℃ and 7.4g of 10% KOH solution were added, stirred for 20 minutes and then cooled to 40 ℃. Then 1.23g of hydrazine hydrate, 9.3g of a sodium diaminocarboxylate solution and 22.8g of water were metered in, after stirring for 20 minutes, 23.31g of isophoronediamine and 117.59g of water were added, stirring was carried out at 40 ℃ for 10 minutes, 454.7g of water was added for dispersion, and the comparative aqueous polyurethane was obtained after removal of the solvent by vacuum distillationDispersion 4 having a solids content of 50.5% by weight, a viscosity of 2471mPa.s (23 ℃), a pH of 8.1 and a particle size of 164.5 nm.

Comparative aqueous polyurethane Dispersion 5

175.5g of polycarbonate polyol 1, 198.6g of polytetramethylene ether glycol 2000, 128.1g of polyether polyol 1, 16.2g of polyether polyol 2, 3.1g of dimethylolpropionic acid, 56.69g ofI and 46.0gH is mixed at 70 ℃, heated to 120 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 1297.62g of acetone at 90 ℃ and 7.4g of 10% KOH solution were added, stirred for 20 minutes and then cooled to 40 ℃. 1.23g of hydrazine hydrate, 11.20g of 2- [ (2-aminoethyl) amino group are then metered in]Sodium ethanesulfonate solution and 30.65g of water were stirred for 20 minutes, then 20.81g of isophoronediamine and 130.59g of water were added, stirred for 10 minutes at 40 ℃ then 255.7g of water were added for dispersion, and the solvent was removed by vacuum distillation to give comparative aqueous polyurethane dispersion 5 having a solid content of 59.9% by weight, a viscosity of 868mPa.s (23 ℃), a pH of 7.5 and a particle size of 209.7 nm.

Comparative aqueous polyurethane Dispersion 6

315g of polytetramethylene ether glycol 2000,67.5g of polytetramethylene ether glycol 1000 and 44.8g of polytetramethylene ether glycolI and 33.9gH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 819.7g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. Then 3.8g of ethylenediamine and 15.6g of 2- [ (2-aminoethyl) amino group were metered in]Ethanesulfonic acidSodium solution, 9.5g of a 50% aqueous solution of 2, 6-diaminohexanoic acid and 96.2g of water were stirred for 20 minutes, 605.6g of water was added for dispersion, and the solvent was distilled off in vacuo to give comparative aqueous polyurethane dispersion 6 having a solid content of 41.6% by weight, a viscosity of 30mPa.s (23 ℃), a pH of 6.7 and a particle size of 509.7 nm.

Comparative aqueous polyurethane Dispersion 7

315g of polyether polyol 1, 67.5g of polytetramethylene ether glycol 1000, 4.8g of dimethylolpropionic acid, 44.8g ofI and 33.9gH is mixed at 70 ℃, heated to 110 ℃ and stirred at this temperature until the actual NCO value of the prepolymer is less than or equal to the theoretical NCO value. The prepolymer was dissolved in 828.7g of acetone at 90 ℃ and after stirring for 20 minutes cooled to 40 ℃. Then 3.8g of ethylenediamine and 15.6g of 2- [ (2-aminoethyl) amino group were metered in]Sodium ethanesulfonate solution and 96.2g of water were stirred for 20 minutes, then 610.6g of water were added for dispersion, and the solvent was removed by vacuum distillation to give comparative aqueous polyurethane dispersion 7 having a solid content of 41.1% by weight, a viscosity of 201mPa.s (23 ℃), a pH of 7.05 and a particle size of 162.7 nm.

Preparation of coating compositions for examples 1-8 and comparative examples 1-7

Composition of the coating composition: 92 parts by weight of an aqueous polyurethane dispersion, 3 parts by weight of2794 and 5 parts by weight of2802。

The coating compositions of examples 1 to 8 and comparative examples 1 to 7 were obtained by mixing the components uniformly according to the above-mentioned composition, wherein the aqueous polyurethane dispersion in the coating composition of example 1 was aqueous polyurethane dispersion 1, the aqueous polyurethane dispersion in the coating composition of example 2 was aqueous polyurethane dispersion 2, and so on. The viscosity of the coating composition was adjusted to 4500mpa.s by Borchi Gel ALA for use.

Coating composition film making process and film performance testing method

Step 1. the coating compositions of examples and comparative examples were knife-coated onto a flat and smooth surface with a film scraper to prepare a wet film having a thickness of 500 μm, and dried at 50 deg.C, 30 minutes and 150 deg.C for 3 minutes in this order to obtain dry film samples;

step 2, taking half dry films, cutting 5cm x 2cm from the half dry films, testing the thickness of the half dry films and weighing the half dry films, and recording the thickness of a film sample as T₀；

Step 3, weighing the dry film, putting the dry film into a test dyeing cup, adding a NaOH solution with the concentration of 1.5 percent, which is 15 times of the weight of the film, and putting the dry film into a laboratory sample dyeing machine to perform high-temperature alkali treatment according to the following process conditions:

raising the temperature from room temperature to 90 ℃, keeping the temperature at the temperature of 4 ℃/min for 15 minutes at the temperature of 90 ℃, then lowering the temperature from 90 ℃ to 50 ℃, keeping the temperature at the temperature of 3 ℃/min, and purchasing a laboratory sample dyeing machine from Shanghai Qianli Automation equipment Co., Ltd, with the model of DYE-24;

and 4, after the high-temperature alkali treatment condition is finished, taking out and cleaning the membrane (at the moment, if the membrane is damaged, the subsequent steps are not needed), sucking the membrane by paper, putting the membrane into a test dyeing cup again, adding an acetic acid solution with the pH value of 4 and the weight 15 times that of the membrane, and putting the membrane into a laboratory sample dyeing machine for high-temperature acid treatment according to the following process conditions:

heating from room temperature to 80 ℃, wherein the heating speed is 3 ℃/min, the heating speed is 1 ℃/min, the temperature is increased from 80 ℃ to 130 ℃, the heating speed is 1 ℃/min, the temperature is kept for 40 minutes at 130 ℃, then, the temperature is reduced from 130 ℃ to 80 ℃, the cooling speed is 1 ℃/min, and finally, the temperature is reduced from 80 ℃ to 50 ℃, and the cooling speed is 3 ℃/min;

and 5, taking out and cleaning the membrane after the high-temperature acid treatment condition is finished, testing the length, width and thickness of the membrane, and recording the length L of the treated membrane sample as the length L of the membrane sample₁Width W of the treated film sample₁Thickness T of the treated film sample₁The swelling ratio R is calculated according to the following formula：

R＝(L₁*W₁*T₁/(5*2*T₀))*100％-1

The swelling ratio is an important index for evaluating the acid and alkali resistance of the film, and lower swelling ratios show higher acid and alkali resistance. The desirable swell ratio in the industry is less than 32%.

And 6, preparing the dry film obtained by the treatment in the step 1 into a dumbbell shape, and testing the modulus at 100%, the tensile strength at break and the elongation at break according to the standard DIN 53504 at the room temperature of 23 ℃ and the relative humidity of 50% under the standard atmospheric pressure.

The higher the 100% modulus, tensile strength at break and elongation at break, the better the mechanical properties of the film. An industrially suitable 100% modulus of not less than 2.5N/mm²Tensile strength at break of not less than 20N/mm²And an elongation at break of greater than 580%.

Results of film testing

Table 1 shows the results of various tests on films formed from the coating compositions of examples 1 to 8 and comparative examples 1 to 7.

Table 1 film test results

As can be seen from examples 1-8 and comparative examples 1-7, the swelling ratios of the films formed from the coating compositions of examples 1-8 are less than 32%, which is much lower than that of the comparative examples, indicating that the films formed from the coating compositions of examples 1-8 have good acid and alkali resistance, especially heat, acid, heat and alkali resistance. And the 100% modulus of the films formed from the coating compositions of examples 1-8 were not less than 2.5N/mm²The breaking tensile strength is not less than 20N/mm²The elongation at break was higher than 580%, indicating that the coating compositions of examples 1-8 formed films with good mechanical properties.

Neither of the systems of comparative examples 1 and 2 for preparing comparative aqueous polyurethane dispersions comprise anions or latent anions having hydroxyl and carboxyl functions with a number average molecular weight of 32g/mol to 400g/molHydrophilizing agents, films formed from comparative coating compositions comprising comparative aqueous polyurethane dispersions, which have been treated with hot acid and hot base, have swelling ratios of more than 32% or even film breakages, i.e., the films formed from the comparative coating compositions do not have good acid and base resistance, and the films formed from the comparative coating compositions all have 100% moduli of less than 2.5N/mm²I.e. the film formed by the comparative coating composition does not have good mechanical properties.

The weight of the anionic or potentially anionic hydrophilic agent having hydroxyl and carboxyl functionality in the system of comparative example 3 having a number average molecular weight of 32g/mol to 400g/mol, based on the weight of the hydrophilic agent of the system, is less than 20%, the system of comparative example 6 for preparing a comparative aqueous polyurethane dispersion comprises only amino acids, which are not anionic or potentially anionic hydrophilic agents having hydroxyl and carboxyl functionality, the comparative coating composition comprising the comparative example 3 or the comparative example 6 aqueous polyurethane dispersion forms a film having a swelling ratio after hot acid and hot base treatment of more than 32%, the film formed by the comparative coating composition does not have good acid and base resistance; and the 100% modulus of the films formed from the comparative coating compositions were all below 2.5N/mm²I.e. the film formed by the comparative coating composition does not have good mechanical properties.

The systems of comparative examples 4 and 5 for preparing comparative aqueous polyurethane dispersions do not contain polytetramethylene ether glycol having a number average molecular weight of not more than 1500g/mol, the comparative coating compositions comprising the comparative aqueous polyurethane dispersions of comparative examples 4 or 5 form films having a swelling ratio after hot acid hot base treatment of more than 32%, the comparative coating compositions do not have good acid and base resistance, and the comparative coating compositions all form films having a 100% modulus of less than 2.5N/mm²I.e. the film formed by the comparative coating composition does not have good mechanical properties.

Comparative example 7 System for preparing a comparative aqueous polyurethane Dispersion without polytetramethylene ether glycol having a number average molecular weight of more than 1500g/mol, comparative coating compositions comprising comparative example 7 comparative aqueous polyurethane Dispersion form films with a swelling ratio of more than 32% after hot acid hot base treatment, comparative example 7The film formed from the coating composition does not have good acid and base resistance and the 100% modulus of the film formed from the comparative coating composition is less than 2.5N/mm²Tensile strength at break of less than 20N/mm²I.e. the film formed by the comparative coating composition does not have good mechanical properties.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing description, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description; and therefore any changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.