High-durability waterborne polyurethane fluoride-free waterproof finishing agent as well as preparation method and application thereof

Abstract

The invention discloses a high-durability waterborne polyurethane fluoride-free waterproof finishing agent as well as a preparation method and application thereof. The preparation method comprises the following steps: adding dihydroxyl-terminated silicone oil into a reactor, and carrying out high-temperature vacuumizing dehydration treatment; when the temperature of the reactor is reduced to a proper temperature, adding isophorone diisocyanate for reaction to obtain a polyurethane prepolymer; adding glycerin monostearate into the reactor for chain extension; adding a proper amount of hydrophilic chain extender into the reactor for chain extension; and adjusting the pH value, and adding water at room temperature to emulsify uniformly to obtain the high-durability waterborne polyurethane fluoride-free waterproof finishing agent. After the textile waterproof agent is applied to a textile, a layer of high-strength, flexible and wear-resistant polymeric membrane can be formed on the surface of the textile, the waterproof performance of the textile is effectively improved, meanwhile, the textile waterproof agent has good air permeability and flexibility, and the hand feeling of the textile is effectively improved. And the waterproof contact angle after multiple times of washing is slightly different from that before washing, the durability is good, and the service life is long.

Description

Technical Field

[0001] The present invention relates to the technical field of textile waterproofing, and particularly relates to a highly durable waterborne polyurethane fluorine-free waterproof finishing agent, its preparation method and application. Background Art

[0002] Due to the excellent performance of waterproof and breathable fabrics in aspects such as oil-water separation, self-cleaning, and medical protection, waterproof and breathable fabrics have become one of the current key research areas. At present, many studies have applied some organic materials with low surface energy, such as fluorine-containing compounds, silicone compounds, etc., and inorganic materials, such as nano-SiO2, TiO2, etc., to endow fabrics with excellent waterproof and breathable properties through methods such as impregnation and spraying, making significant progress in the research of waterproof and breathable fabrics.

[0003] However, although the addition of organic fluorine can endow fabrics with excellent waterproof and breathable properties to a certain extent, the longer the perfluoroalkyl chain, the worse the biodegradability of the waterproof and breathable membrane. In addition, the biodegradability of silicone and inorganic material waterproof and breathable membranes is higher than that of fluorine-containing waterproof and breathable membranes, but the waterproof effect of silicone is poor, and the air permeability and durability of inorganic coatings are poor. Therefore, designing environmentally friendly fluorine-free waterproof and breathable membranes to endow fabrics with excellent waterproofness, air permeability, and durability still requires key breakthroughs. Summary of the Invention

[0004] Aiming at the above deficiencies, the purpose of the present invention is to provide a highly durable waterborne polyurethane fluorine-free waterproof finishing agent with good safety, waterproofness, air permeability, and durability, and its preparation method.

[0005] The technical solution provided by the present invention to achieve the above purpose is as follows:

[0006] A preparation method of a highly durable waterborne polyurethane fluorine-free waterproof finishing agent, which comprises the following steps:

[0007] (1) High-temperature vacuum dehydration: Add an appropriate amount of bis-hydroxy-terminated silicone oil to a reactor and perform vacuum dehydration treatment at 110-130°C for 1-3 hours;

[0008] (2) Preparation of polyurethane prepolymer: Lower the temperature of the reactor to 55-65°C, add an appropriate amount of isophorone diisocyanate, and keep the temperature for reaction for 1-3 hours, then raise the temperature to 70-80°C and keep the temperature for reaction for 2-4 hours to obtain a polyurethane prepolymer;

[0009] (3) Chain extension I: Add an appropriate amount of glycerol monostearate to the reactor for chain extension and keep the temperature at 65-75°C for reaction for 1-3 hours;

[0010] (4) Chain extension II: Add an appropriate amount of hydrophilic chain extender into the reactor for chain extension, and keep the temperature at 65 - 75 °C for 1 - 3 h for the reaction.

[0011] (5) pH adjustment: Add an appropriate amount of acetic acid into the reactor to adjust the pH to 6 - 7.

[0012] (6) Emulsification: Lower the temperature of the reactor to room temperature, add water and emulsify evenly to obtain a high - durability water - borne polyurethane fluorine - free waterproof finishing agent.

[0013] As a preferred embodiment of the present invention, the molecular weight of the di - terminal hydroxyl silicone oil is 500 - 3000.

[0014] As a preferred embodiment of the present invention, the molar ratio of the di - terminal hydroxyl silicone oil to the glycerol monostearate is 0.5 - 1.2:1.

[0015] As a preferred embodiment of the present invention, the molar ratio of the isophorone diisocyanate to the total molar amount of the di - terminal hydroxyl silicone oil and the glycerol monostearate is 1.2 - 1.7:1.

[0016] As a preferred embodiment of the present invention, the hydrophilic chain extender is N - methyldiethanolamine, and the molar ratio of the hydrophilic chain extender to the isophorone diisocyanate is 0.2 - 0.5:1.

[0017] A high - durability water - borne polyurethane fluorine - free waterproof finishing agent is prepared by the above - mentioned preparation method of the high - durability water - borne polyurethane fluorine - free waterproof finishing agent.

[0018] A high - durability water - borne polyurethane fluorine - free waterproof finishing agent is applied to textile waterproofing. After the application of the present invention to textiles, a high - strength, flexible and wear - resistant polymer film can be formed on the surface of the textiles, effectively improving the waterproof property of the textiles. At the same time, it has good air permeability and flexibility, effectively improving the hand feeling of the textiles. Moreover, the waterproof contact angle after multiple washes is not much different from that before washing, with good durability and a long service life.

[0019] The beneficial effects of the present invention are as follows: The formulation of the present invention is reasonable. A polyurethane prepolymer is prepared by reacting a dihydroxyl-terminated silicone oil with an isocyanate. The introduction of the dihydroxyl-terminated silicone oil can endow the prepared polyurethane with a low surface energy, making the polyurethane film have good waterproofness and flexibility. A glyceryl monostearate is used to chain-extend the polyurethane prepolymer. The introduction of the glyceryl monostearate enables the waterproof groups to be arranged orderly on the polyurethane macromolecular chain. At the same time, fabric fibers are composed of many atomic groups bonded by covalent bonds. These atomic groups are called the monofunctional groups of the macromolecule, and their degree of polymerization determines the chemical and physical properties of the fiber. And due to the lateral attraction of the macromolecules inside the fiber, the macromolecules are arranged orderly with each other, resulting in a high degree of geometric regularity of the fiber. Therefore, a large number of urethane bonds and hydrogen bonds present in the aqueous polyurethane can generate a strong adhesion force with the fabric, enabling the use of the aqueous polyurethane as a substrate to endow the fabric with excellent waterproofness, breathability, and durability. The high-durability aqueous polyurethane fluorine-free waterproof finishing agent prepared by using a composite soft segment of dihydroxyl-terminated silicone oil and glyceryl monostearate can endow the prepared polyurethane with a low surface energy, making the polyurethane film have good waterproofness and flexibility. Thus, after applying it to the polyester-cotton fabric for waterproof treatment, that is, forming a high-strength, flexible, and wear-resistant polymer film on the surface of the polyester-cotton fabric, effectively improving the waterproofness of the fabric. The introduction of the silicone chain segment makes the molecular chain segment of the prepared fluorine-free waterproof agent have good flexibility, enabling the fabric after finishing to obtain an excellent handfeel. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram of the method steps of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] Example 1: Refer to Figure 1 , the embodiment of the present invention provides a preparation method of a high-durability aqueous polyurethane fluorine-free waterproof finishing agent, which includes the following steps:

[0022] (1) High-temperature vacuum dehydration: Add an appropriate amount of dihydroxyl-terminated silicone oil to the reactor and perform vacuum dehydration treatment at 110°C for 3 h; the molecular weight of the dihydroxyl-terminated silicone oil is preferably 2000;

[0023] (2) Preparation of polyurethane prepolymer: Lower the temperature of the reactor to 55°C, add an appropriate amount of isophorone diisocyanate, and keep the temperature for reaction for 3 h, then raise the temperature to 70°C and keep the temperature for reaction for 4 h to obtain a polyurethane prepolymer;

[0024] (3) Chain extension I: Add an appropriate amount of glyceryl monostearate to the reactor for chain extension and keep the temperature at 65°C for reaction for 3 h;

[0025] Among them, the molar ratio of the dihydroxyl-terminated silicone oil to the glyceryl monostearate is 0.8:1; the molar ratio of the isophorone diisocyanate to the total molar number of the dihydroxyl-terminated silicone oil and the glyceryl monostearate is 1.3:1;

[0026] (4) Chain extension II: Add an appropriate amount of N-methyldiethanolamine as a hydrophilic chain extender to the reactor for chain extension, and keep the temperature at 65 °C for 3 h for reaction;

[0027] Among them, the molar ratio of N-methyldiethanolamine to isophorone diisocyanate is 0.4:1;

[0028] (5) pH adjustment: Add an appropriate amount of acetic acid to the reactor for 30 min of reaction, and adjust the pH to 6-7;

[0029] (6) Emulsification: Lower the temperature of the reactor to room temperature, add water and emulsify evenly to obtain a high-durability waterborne polyurethane fluorine-free waterproofing finishing agent. The amount of water added is preferably such that the solid content of the high-durability waterborne polyurethane fluorine-free waterproofing finishing agent is 30%.

[0030] Example 2, the present invention provides a preparation method of a high-durability waterborne polyurethane fluorine-free waterproofing finishing agent, which includes the following steps:

[0031] (1) High-temperature vacuum dehydration: Add an appropriate amount of dihydroxyl-terminated silicone oil to the reactor and perform vacuum dehydration treatment at 120 °C for 2 h; the molecular weight of the dihydroxyl-terminated silicone oil is preferably 2000;

[0032] (2) Preparation of polyurethane prepolymer: Lower the temperature of the reactor to 60 °C, add an appropriate amount of isophorone diisocyanate, and keep the temperature for 2 h for reaction, then raise the temperature to 75 °C and keep the temperature for 3 h for reaction to obtain a polyurethane prepolymer;

[0033] (3) Chain extension I: Add an appropriate amount of glycerol monostearate to the reactor for chain extension, and keep the temperature at 70 °C for 2 h for reaction;

[0034] Among them, the molar ratio of dihydroxyl-terminated silicone oil to glycerol monostearate is 1:1; the molar ratio of isophorone diisocyanate to the total molar number of dihydroxyl-terminated silicone oil and glycerol monostearate is 1.5:1;

[0035] (4) Chain extension II: Add an appropriate amount of N-methyldiethanolamine as a hydrophilic chain extender to the reactor for chain extension, and keep the temperature at 70 °C for 2 h for reaction;

[0036] Among them, the molar ratio of N-methyldiethanolamine to isophorone diisocyanate is 0.5:1;

[0037] (5) pH adjustment: Add an appropriate amount of acetic acid to the reactor for 30 min of reaction, and adjust the pH to 6-7;

[0038] (6) Emulsification: Lower the temperature of the reactor to room temperature, add water and emulsify evenly to obtain a high-durability waterborne polyurethane fluorine-free waterproofing finishing agent. The amount of water added is preferably such that the solid content of the high-durability waterborne polyurethane fluorine-free waterproofing finishing agent is 30%.

[0039] Example 3. The embodiment of the present invention provides a preparation method of a highly durable waterborne polyurethane fluorine-free waterproofing finishing agent, which comprises the following steps:

[0040] (1) High-temperature vacuum dehydration: Add an appropriate amount of bis-hydroxy-terminated silicone oil to the reactor and perform vacuum dehydration treatment at 130 °C for 1 h; the molecular weight of the bis-hydroxy-terminated silicone oil is preferably 1500;

[0041] (2) Preparation of polyurethane prepolymer: Lower the temperature of the reactor to 65 °C, add an appropriate amount of isophorone diisocyanate, and keep the temperature for reaction for 1 h, then raise the temperature to 80 °C and keep the temperature for reaction for 2 h to obtain a polyurethane prepolymer;

[0042] (3) Chain extension I: Add an appropriate amount of glycerol monostearate to the reactor for chain extension and keep the temperature at 75 °C for reaction for 1 h;

[0043] Among them, the molar ratio of bis-hydroxy-terminated silicone oil to glycerol monostearate is 1.2:1; the molar ratio of isophorone diisocyanate to the total molar number of bis-hydroxy-terminated silicone oil and glycerol monostearate is 1.6:1;

[0044] (4) Chain extension II: Add an appropriate amount of N-methyldiethanolamine as a hydrophilic chain extender to the reactor for chain extension and keep the temperature at 75 °C for reaction for 1 h;

[0045] Among them, the molar ratio of N-methyldiethanolamine to isophorone diisocyanate is 0.2:1;

[0046] (5) pH adjustment: Add an appropriate amount of acetic acid to the reactor and react for 30 min to adjust the pH to 6-7;

[0047] (6) Emulsification: Lower the temperature of the reactor to room temperature, add water and emulsify evenly to obtain a highly durable waterborne polyurethane fluorine-free waterproofing finishing agent. The amount of water added is preferably such that the solid content of the highly durable waterborne polyurethane fluorine-free waterproofing finishing agent is 30%.

[0048] Example 4. The embodiment of the present invention provides a preparation method of a highly durable waterborne polyurethane fluorine-free waterproofing finishing agent, which comprises the following steps:

[0049] (1) High-temperature vacuum dehydration: Add an appropriate amount of bis-hydroxy-terminated silicone oil to the reactor and perform vacuum dehydration treatment at 120 °C for 2 h; the molecular weight of the bis-hydroxy-terminated silicone oil is preferably 3000;

[0050] (2) Preparation of polyurethane prepolymer: Lower the temperature of the reactor to 60 °C, add an appropriate amount of isophorone diisocyanate, and keep the temperature for reaction for 2 h, then raise the temperature to 75 °C and keep the temperature for reaction for 3 h to obtain a polyurethane prepolymer;

[0051] (3) Chain extension I: Add an appropriate amount of glycerol monostearate to the reactor for chain extension, and keep the temperature at 70 °C for 2 h;

[0052] Among them, the molar ratio of the dihydroxy-terminated silicone oil to glycerol monostearate is 0.8:1; the molar ratio of isophorone diisocyanate to the total molar amount of dihydroxy-terminated silicone oil and glycerol monostearate is 1.7:1;

[0053] (4) Chain extension II: Add an appropriate amount of N-methyldiethanolamine as a hydrophilic chain extender to the reactor for chain extension, and keep the temperature at 70 °C for 2 h;

[0054] Among them, the molar ratio of N-methyldiethanolamine to isophorone diisocyanate is 0.5:1;

[0055] (5) pH adjustment: Add an appropriate amount of acetic acid to the reactor and react for 30 min to adjust the pH to 6-7;

[0056] (6) Emulsification: Lower the temperature of the reactor to room temperature, add water and emulsify evenly to obtain a high-durability waterborne polyurethane fluorine-free waterproof finishing agent. The amount of water added is preferably such that the solid content of the high-durability waterborne polyurethane fluorine-free waterproof finishing agent is 30%.

[0057] Example 5, the present invention provides a preparation method of a high-durability waterborne polyurethane fluorine-free waterproof finishing agent, which includes the following steps:

[0058] (1) High-temperature vacuum dehydration: Add an appropriate amount of dihydroxy-terminated silicone oil to the reactor and perform vacuum dehydration treatment at 120 °C for 2 h; the molecular weight of the dihydroxy-terminated silicone oil is preferably 1000;

[0059] (2) Preparation of polyurethane prepolymer: Lower the temperature of the reactor to 60 °C, add an appropriate amount of isophorone diisocyanate, and keep the temperature for 2 h, then raise the temperature to 75 °C and keep the temperature for 3 h to obtain a polyurethane prepolymer;

[0060] (3) Chain extension I: Add an appropriate amount of glycerol monostearate to the reactor for chain extension, and keep the temperature at 70 °C for 2 h;

[0061] Among them, the molar ratio of the dihydroxy-terminated silicone oil to glycerol monostearate is 0.7:1; the molar ratio of isophorone diisocyanate to the total molar amount of dihydroxy-terminated silicone oil and glycerol monostearate is 1.6:1;

[0062] (4) Chain extension II: Add an appropriate amount of N-methyldiethanolamine as a hydrophilic chain extender to the reactor for chain extension, and keep the temperature at 70 °C for 2 h;

[0063] Among them, the molar ratio of N-methyldiethanolamine to isophorone diisocyanate is 0.4:1;

[0064] (5) Adjust the pH value: Add an appropriate amount of acetic acid to the reactor and react for 30 minutes, then adjust the pH value to 6 - 7;

[0065] (6) Emulsification: Cool the temperature of the reactor to room temperature, add water and emulsify evenly to obtain a high - durability water - borne polyurethane fluorine - free waterproof finishing agent. The amount of added water is preferably such that the solid content of the high - durability water - borne polyurethane fluorine - free waterproof finishing agent is 30%.

[0066] The above - mentioned embodiments are only the better implementation modes of the present invention. The present invention cannot list all the implementation modes one by one. Any technical solution adopting one of the above - mentioned embodiments or equivalent changes made according to the above - mentioned embodiments is within the protection scope of the present invention.

[0067] Next, the high - durability water - borne polyurethane fluorine - free waterproof finishing agents prepared in Examples 1 - 5 were used to finish textiles for testing. In this example, the textile selected was a polyester - cotton blended fabric. In other examples, the textile can also be a polyester - cotton shuttle fabric, a cotton blended fabric, etc. The dosage of the finishing agent was 20 g / L, two - dip two - nip, dried at 100 °C, baked at 160 °C for 1 - 2 minutes, and cooled to room temperature to test the waterproof effect.

[0068] As shown in Table 1 below, the waterproof and durability test results of the high - durability water - borne polyurethane fluorine - free waterproof finishing agents prepared in Examples 1 - 5 are presented.

[0069] Table 1

[0070]

[0071] It can be seen from Table 1 that the textiles finished with the high - durability water - borne polyurethane fluorine - free waterproof finishing agent prepared by the present invention have excellent waterproof effects. A high - strength, flexible and wear - resistant polymer film is formed on the surface of the textiles, with good waterproof performance and good washability. Example 2 is the best example. The high - durability water - borne polyurethane fluorine - free waterproof finishing agent prepared can significantly improve the waterproof property of the polyester - cotton blended fabric. When its dosage reaches 20 g / L, the waterproof contact angle of the polyester - cotton blended fabric can be increased from 87.7° to 141.6°. In addition, the polyester - cotton blended fabric treated with the product of the present invention has good air permeability and washability. The difference in the waterproof contact angle after 20 times of washing and before washing is not significant, with good durability and long service life.

[0072] Based on the disclosure and teachings of the above specification, those skilled in the art to which the present invention pertains can also make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention. The use of other finishing agents and preparation methods that are the same or similar thereto are all within the protection scope of the present invention.

Claims

1. A preparation method of a highly durable waterborne polyurethane fluorine-free waterproof finishing agent, characterized in that, It includes the following steps: (1) High-temperature vacuum dehydration: Add an appropriate amount of dihydroxyl-terminated silicone oil into a reactor, and conduct vacuum dehydration treatment at 110-130 °C for 1-3 h; (2) Preparation of polyurethane prepolymer: Lower the temperature of the reactor to 55-65 °C, add an appropriate amount of isophorone diisocyanate, and keep the temperature for reaction for 1-3 h, then raise the temperature to 70-80 °C and keep the temperature for reaction for 2-4 h to obtain a polyurethane prepolymer; (3) Chain extension I: Add an appropriate amount of glyceryl monostearate into the reactor for chain extension, and keep the temperature for reaction at 65-75 °C for 1-3 h; (4) Chain extension II: Add an appropriate amount of hydrophilic chain extender into the reactor for chain extension, and keep the temperature for reaction at 65-75 °C for 1-3 h; (5) pH adjustment: Add an appropriate amount of acetic acid into the reactor to adjust the pH to 6-7; (6) Emulsification: Lower the temperature of the reactor to room temperature, add water and emulsify evenly to obtain a high-durability waterborne polyurethane fluorine-free waterproof finishing agent.

2. The preparation method of the high-durability waterborne polyurethane fluorine-free waterproof finishing agent according to claim 1, characterized in that, The molecular weight of the dihydroxyl-terminated silicone oil is 500-3000.

3. The preparation method of the high-durability waterborne polyurethane fluorine-free waterproof finishing agent according to claim 1, characterized in that, The molar ratio of the dihydroxyl-terminated silicone oil to glyceryl monostearate is 0.5-1.2:

1.

4. The preparation method of the high-durability waterborne polyurethane fluorine-free waterproof finishing agent according to claim 3, characterized in that, The molar ratio of isophorone diisocyanate to the total molar amount of the dihydroxyl-terminated silicone oil and glyceryl monostearate is 1.2-1.7:

1.

5. The preparation method of the high-durability waterborne polyurethane fluorine-free waterproof finishing agent according to claim 4, characterized in that, The hydrophilic chain extender is N-methyldiethanolamine.

6. The preparation method of the high-durability waterborne polyurethane fluorine-free waterproof finishing agent according to claim 5, characterized in that, The molar ratio of the hydrophilic chain extender to isophorone diisocyanate is 0.2-0.5:

1.

7. A high-durability waterborne polyurethane fluorine-free waterproof finishing agent, characterized in that, It is prepared by using the preparation method of the high-durability waterborne polyurethane fluorine-free waterproof finishing agent according to any one of claims 1-6.

8. Application of a highly durable waterborne polyurethane fluorine-free waterproof finishing agent, characterized in that, The high-durability waterborne polyurethane fluorine-free waterproof finishing agent prepared by using the preparation method of the high-durability waterborne polyurethane fluorine-free waterproof finishing agent according to any one of claims 1-6 is applied to textile waterproofing.

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