阅读说明：本技术 一种抗吸潮水性聚氨酯分散体及其制备方法与应用 (Moisture-absorption-resistant aqueous polyurethane dispersion and preparation method and application thereof ) 是由 高强 郭艳欣 陈亚磊 朱小强 张大华 于 2020-06-05 设计创作，主要内容包括：本发明涉及一种抗吸潮水性聚氨酯分散体及其制备方法与应用,本发明属于水性聚氨酯涂层树脂领域。本发明将聚醚二元醇、官能度≥3的聚醚多元醇、侧链烷烃二元醇和多异氰酸酯一起反应得到预聚物,然后加入扩链剂继续反应,得到抗吸潮水性聚氨酯涂层树脂分散体,利用该抗吸潮水性聚氨酯涂层树脂分散体可以制备水性聚氨酯涂层树脂。本发明最终制备的水性聚氨酯涂层树脂具有既可以阻隔水汽、遇潮不发雾等特点。(The invention relates to a moisture-absorption-resistant aqueous polyurethane dispersion and a preparation method and application thereof, belonging to the field of aqueous polyurethane coating resin. According to the invention, polyether diol, polyether polyol with the functionality degree of more than or equal to 3, side-chain alkane diol and polyisocyanate are reacted together to obtain prepolymer, then a chain extender is added for continuous reaction to obtain the moisture-absorption-resistant aqueous polyurethane coating resin dispersoid, and the moisture-absorption-resistant aqueous polyurethane coating resin dispersoid can be used for preparing the aqueous polyurethane coating resin. The finally prepared waterborne polyurethane coating resin has the characteristics of water vapor barrier, no fogging when meeting moisture and the like.)

1. A preparation method of moisture-absorption-resistant aqueous polyurethane dispersoid is characterized by comprising the following steps: the method comprises the following steps:

(1) putting polyether diol, polyether polyol with functionality being more than or equal to 3, side-chain alkane diol and polyisocyanate into a reaction kettle, adding a catalyst and a solvent after uniformly stirring, and reacting for 1-2h at 60-100 ℃ to obtain a PU prepolymer;

(2) cooling the PU prepolymer obtained in the step (1) to 65 ℃, adding a hydrophilic chain extender, a polyol chain extender and a solvent, wherein the mass ratio of the hydrophilic chain extender to the polyol chain extender to the polyether glycol in the step (1) is (2-10): (0-10): (25-80), heating to 60-90 ℃, and continuing to react for 3-6 h;

(3) cooling and adding a solvent for dilution;

(4) when the temperature is reduced to below 35 ℃, adding a neutralizing agent, and neutralizing for 10-30 min;

(5) dispersing the PU prepolymer obtained in the step (4) in water under high-speed stirring to obtain a PU dispersoid;

(6) preparing an amine chain extender into an aqueous solution with the mass fraction of 5-40%, adding the aqueous solution into the PU dispersoid obtained in the step (5), wherein the mass ratio of the amine chain extender to the polyether glycol in the step (1) is (1-4.0): (25-80), stirring for 10-45 min;

(7) heating to 40-65 ℃, and distilling under reduced pressure to remove the solvent to obtain the moisture-absorption-resistant waterborne polyurethane coating resin dispersoid;

in the step (1), the compound is polypropylene oxide glycol or a mixture of polytetrahydrofuran glycol and polypropylene oxide glycol, wherein the molecular weight of the polypropylene oxide glycol or the polytetrahydrofuran glycol is 500-3500;

in the step (1), the polyether polyol with the functionality of more than or equal to 3 comprises: polyglycerol, the molecular weight of which is 1000-4000;

in the step (1), the side-chain alkane diol comprises: one or two of stearic acid monoglyceride and glycerol monooleate;

in the step (1), the polyisocyanate includes: one or two of toluene diisocyanate and 4, 4-diphenylmethane diisocyanate;

in the step (1), the mass ratio of polyether diol, polyether polyol with the functionality of more than or equal to 3, side chain alkane diol and polyisocyanate is (25-80): (4-10): (1.0-5): (10-30).

2. The method for producing a moisture-absorption-resistant aqueous polyurethane dispersion according to claim 1, wherein: in the step (1), the catalyst comprises: stannous octoate, wherein the mass ratio of the catalyst to the polyether glycol is 0-0.0001: 25-80.

3. The method for producing a moisture-absorption-resistant aqueous polyurethane dispersion according to claim 1, wherein: in the step (1) and the step (2), the solvent is one or a mixture of two of acetone and butanone.

4. The method for producing the moisture-absorption-resistant aqueous polyurethane dispersion according to claim 1, which is characterized in thatCharacterized in that: in the step (2), the hydrophilic chain extender is a chain extender containing an anionic group, a cationic group or a nonionic group, and the anionic group chain extender is carboxylate radical-COO^-The chain extender (2).

5. The method for producing a moisture-absorption-resistant aqueous polyurethane dispersion according to claim 1, wherein: in the step (2), the polyol chain extender is one of 1, 4-butanediol and neopentyl glycol.

6. The method for producing a moisture-absorption-resistant aqueous polyurethane dispersion according to claim 1, wherein: in the step (4), the neutralizing agent is triethylamine.

7. The method for producing a moisture-absorption-resistant aqueous polyurethane dispersion according to claim 1, wherein: in the step (6), the amine chain extender is ethylenediamine.

8. The moisture-absorption-resistant aqueous polyurethane dispersion produced by the method for producing a moisture-absorption-resistant aqueous polyurethane dispersion according to claim 1.

9. Use of the moisture-resistant aqueous polyurethane dispersion according to claim 8 for the preparation of a moisture-resistant aqueous polyurethane coating resin.

10. Use according to claim 9, characterized in that it comprises the following steps:

stirring and thickening the moisture-absorption-resistant aqueous polyurethane dispersoid, the wetting agent, the flatting agent, the thickening agent, the curing agent and the color paste to 8000-15000cp viscosity, and then defoaming to obtain the moisture-absorption-resistant aqueous polyurethane coating resin;

the moisture absorption resistant aqueous polyurethane dispersoid, the wetting agent, the flatting agent, the thickening agent, the curing agent and the color paste have the mass ratio of 95: 0.5: 0.3: 2: 0.3: 2.

The technical field is as follows:

the invention belongs to the technical field of waterborne polyurethane coating resin, and particularly relates to moisture-absorption-resistant waterborne polyurethane coating resin as well as a preparation method and application thereof.

Background art:

the waterborne polyurethane is widely applied to the fields of coatings, adhesives, leather finishing agents, fabric coatings and the like due to the characteristics of no toxicity, environmental protection and the like. The film forming process of the waterborne polyurethane belongs to the fusion of a multiphase system, and the air permeability and the moisture permeability of the waterborne polyurethane can be well embodied in the application field. However, when the cleaning agent is used, liquid such as water, beverage, blood, urine and the like easily penetrates into the back surface of the aqueous polyurethane coating, and the cleaning of printing stains and the like is difficult. Therefore, the water permeability and air permeability of the waterborne polyurethane coating are improved, and the application of the waterborne polyurethane in the field of household care can be greatly expanded.

At present, a plurality of methods for improving the water permeability and the air permeability of the water-based resin exist. For example, the sizing amount of the coating is increased to increase the thickness of the coating, the wax assistant is used to improve the water repellency, the filler amount is reduced to increase the film forming compactness, and the like, all the methods belong to physical modification, the effect is limited, and the cost is greatly increased. In the field of chemical modification, U.S. Pat. Nos. 5,532,85, 4619853, 4643930, etc. employ introduction of fluorine-containing components to improve water permeability; US5558916 describes the preparation of water impermeable membranes from various hydrophobic components, but these methods are complicated and costly to produce, and are accompanied by other disadvantages in physical properties. U.S. patent No. 2003087567 improves the moisture absorption resistance of aqueous polyurethane by grafting an aliphatic alcohol containing aliphatic side chains, but the method still has limited moisture barrier effect, and in humid air, the surface of the fabric coating often has defects such as fogging or spots. Therefore, the moisture absorption resistant water-based polyurethane coating resin which can block water vapor and has no fogging on the surface is developed, so that the application requirement can be greatly met, and meanwhile, the application of the water-based polyurethane in the field of fabric coatings can be widened.

The invention content is as follows:

the purpose of the invention is as follows: the technical problem to be solved is to provide a moisture-absorption-resistant aqueous polyurethane dispersion to solve the problems that the aqueous polyurethane coating resin in the prior art has poor water-resisting property, and the surface is easy to fog or generate spots and the like.

The invention also aims to provide a preparation method of the moisture-absorption-resistant aqueous polyurethane dispersion

The invention finally aims to solve the technical problem of providing the application of the moisture-absorption-resistant water-based polyurethane coating resin.

The technical scheme is as follows: in order to solve the technical problems, the invention adopts the following technical scheme:

a preparation method of a moisture-absorption-resistant aqueous polyurethane dispersion comprises the following steps:

(1) putting polyether diol, polyether polyol with functionality being more than or equal to 3, side-chain alkane diol and polyisocyanate into a reaction kettle, adding a catalyst and a solvent after uniformly stirring, and reacting for 1-2h at 60-100 ℃ to obtain a PU prepolymer;

(2) cooling the PU prepolymer obtained in the step (1) to 65 ℃, adding a hydrophilic chain extender, a polyol chain extender and a solvent, wherein the mass ratio of the hydrophilic chain extender to the polyol chain extender to the polyether glycol in the step (1) is (2-10): (0-10): (25-80), heating to 60-90 ℃, and continuing to react for 3-6 h;

(3) cooling and adding a solvent for dilution;

(4) when the temperature is reduced to below 35 ℃, adding a neutralizing agent, and neutralizing for 10-30 min;

(5) dispersing the PU prepolymer obtained in the step (4) in water under high-speed stirring to obtain a PU dispersoid;

(6) preparing an amine chain extender into an aqueous solution with the mass fraction of 5-40%, adding the aqueous solution into the PU dispersoid obtained in the step (5), wherein the mass ratio of the amine chain extender to the polyether glycol in the step (1) is (1-4.0): (25-80), stirring for 10-45 min;

(7) heating to 40-65 ℃, and distilling under reduced pressure to remove the solvent to obtain the moisture-absorption-resistant waterborne polyurethane coating resin dispersoid. The moisture-absorption-resistant aqueous polyurethane coating resin dispersion has a solid content of 15 to 50 wt%, preferably 25 to 40 wt%; the pH value is 6-11, preferably 6.5-9, and the average particle size is 80-450nm, preferably 100-300nm, more preferably 120-250 nm.

In the step (1), the compound is polypropylene oxide glycol or a mixture of polytetrahydrofuran glycol and polypropylene oxide glycol, wherein the molecular weight of the polypropylene oxide glycol or the polytetrahydrofuran glycol is 3500-3500, preferably 3000-1500.

In the step (1), the polyether polyol with the functionality of more than or equal to 3 comprises: polyglycerol, the molecular weight of which is 1000-4000, preferably 2000-3500, more preferably MN-3050D of great eastern Lanxingdong.

In the step (1), the side chain alkane diol is: one or two of stearic acid monoglyceride and glycerol monooleate, and most preferably stearic acid monoglyceride;

in the step (1), the polyisocyanate includes: one or two of toluene diisocyanate and 4, 4-diphenylmethane diisocyanate, preferably toluene diisocyanate, and most preferably TDI-80

In the step (1), the mass ratio of polyether diol, polyether polyol with the functionality degree of more than or equal to 3, side chain alkane diol and polyisocyanate is as follows: 25-80: 4-10: 1.0-5: 10-30.

In the step (1), the catalyst comprises: stannous octoate, wherein the mass ratio of the catalyst to the polyether glycol is 0-0.0001: 25-80.

In the step (1) and the step (2), the solvent is one or a mixture of two of acetone and butanone.

In the step (2), the hydrophilic chain extender is a chain extender containing an anionic group, a cationic group or a nonionic group, and the anionic group chain extender is carboxylate radical-COO^-The chain extender (b) is preferably dimethylolpropionic acid or dimethylolbutyric acid, and most preferably dimethylolpropionic acid.

In the step (2), the polyol chain extender is one of 1, 4-butanediol and neopentyl glycol.

In the step (4), the neutralizing agent is triethylamine.

In the step (6), the amine chain extender is ethylenediamine.

The moisture-absorption-resistant aqueous polyurethane dispersion prepared by the preparation method of the moisture-absorption-resistant aqueous polyurethane dispersion.

The moisture-absorption-resistant aqueous polyurethane dispersion is applied to preparation of moisture-absorption-resistant aqueous polyurethane coating resin.

A preparation method of moisture-absorption-resistant water-based polyurethane coating resin comprises the following steps:

stirring and thickening the moisture-absorption-resistant aqueous polyurethane dispersoid, the wetting agent, the flatting agent, the thickening agent, the curing agent and the color paste to 8000-15000cp viscosity, and then defoaming to obtain the moisture-absorption-resistant aqueous polyurethane coating resin;

the moisture-absorption-resistant aqueous polyurethane dispersoid, the thickening agent, the flatting agent, the wetting agent, the defoaming agent, the curing agent and the color paste have the mass ratio of (93-99.7): (0.2-2): (0.05-1): (0.05-1): (0-0.2): (0-3): (1-5);

preferably, the wetting agent is Silok 8000; the leveling agent is Silok 8144, the thickening agent is UH-450VF, the curing agent is XWB-F115, and the color paste is KA-920.

The thickener comprises an associated thickener and an alkali soluble swelling thickener, preferably a polyurethane associated thickener, and most preferably a thickener of UH-450 VF;

the leveling agent comprises but is not limited to polyether silicone oil, polyester silicone oil and polyether polyester silicone oil, preferably polyether silicone oil type leveling agent; the most preferred leveling agent is Silok 8144;

the wetting agent includes but is not limited to polyether silicone oil, polyether siloxane, preferably polyether silicone oil wetting agent; the most preferred wetting agent is Silok 8000;

the defoaming agent includes but is not limited to silicone defoaming agents and non-silicone defoaming agents, preferably non-silicone defoaming agents.

The curing agent is a curing agent commonly used in the art, preferably polyether modified isocyanate polymer, and the most preferred curing agent is XWB-F115.

Has the advantages that:

the moisture-absorption-resistant aqueous polyurethane coating resin prepared by the invention has good strip-sticking tension, can well block the transmission of water vapor, cannot fog when meeting moisture, and has an obvious moisture absorption resistance function.

The specific implementation mode is as follows:

the present invention can be better understood from the following examples, however, those skilled in the art will readily appreciate that the descriptions of the examples are only for the purpose of illustrating the present invention and should not be taken as limiting the invention as detailed in the claims.

The invention uses the following raw material models and manufacturer information:

toluene diisocyanate (TDI-80): wanhua chemistry

Diphenylmethane diisocyanate (MDI-50): wanhua chemistry

Polypropylene oxide glycol (PPG 2000): national institute of chemical engineering

Polytetrahydrofuran diol (PTMG-2000): xiaoxing chemical industry

Glycerol Monostearate (GMS): shanghai alading

Dimethylolpropionic acid (DMPA): pasteur

1, 4-Butanediol (BDO): shanghai alading

Ethylenediamine (EDA): chemistry of Dow

Triethylamine (TEA): science of west longu

Bismuth octoate (8108): lead ahead

Acetone (AC): beijing Yanshan petrochemical

Deionized water (H)₂O): self-made

A preparation method of a moisture-absorption-resistant aqueous polyurethane dispersion comprises the following specific steps:

(1) putting polyether diol, polyether polyol with functionality being more than or equal to 3, side-chain alkane diol and polyisocyanate into a reaction kettle, adding a catalyst and a solvent after uniformly stirring, and reacting for 1-2h at 60-100 ℃ to obtain a PU prepolymer;

(2) cooling the PU prepolymer obtained in the step (1) to 65 ℃, adding a hydrophilic chain extender, a polyol chain extender and a solvent, heating to 60-90 ℃, and continuing to react for 3-6 hours;

(3) cooling and adding a solvent for dilution;

(4) when the temperature is reduced to below 35 ℃, adding a neutralizing agent, and neutralizing for 10-30 min;

(5) dispersing the PU prepolymer obtained in the step (4) in water under high-speed stirring to obtain a PU dispersoid;

(6) preparing an amine chain extender into an aqueous solution with the mass fraction of 5-40%, adding the aqueous solution into the PU dispersoid obtained in the step (5), and stirring for 10-45 min;

(7) heating to 40-65 ℃, and distilling under reduced pressure to remove the solvent to obtain the moisture-absorption-resistant waterborne polyurethane coating resin dispersoid.

In the invention, the solvent does not participate in the reaction, and the addition amount of the solvent only needs to meet the reaction requirement.

The addition amount of each component in the first, the second and the third embodiments 1 to 3 and 1 to 2 is added according to the mass fraction shown in the following table.

A preparation method of moisture-absorption-resistant water-based polyurethane coating resin comprises the following steps:

stirring and thickening the moisture-absorption-resistant aqueous polyurethane dispersoid, the wetting agent, the flatting agent, the thickening agent, the curing agent and the color paste to 8000-15000cp viscosity, and then defoaming to obtain the moisture-absorption-resistant aqueous polyurethane coating resin;

the moisture-absorption-resistant aqueous polyurethane dispersoid, the thickening agent, the flatting agent, the wetting agent, the defoaming agent, the curing agent and the color paste have the mass ratio of (93-99.7): (0.2-2): (0.05-1): (0.05-1): (0-0.2): (0-3): (1-5);