Polyurethane adhesive and preparation method thereof
By combining components A and B, and especially by using a slow-release design of the cyclodextrin-encapsulated foaming agent and a wetting agent, the problem of insufficient bonding strength of polyurethane products on clothing or shoe surfaces has been solved, achieving a high-strength, washable bonding effect.
Patent Information
- Application Number
- CN202510792887.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-13
- Publication Date
- 2025-11-14
AI Technical Summary
Existing polyurethane products have insufficient bonding strength on clothing or shoe surfaces, especially due to poor bonding caused by material differences.
The adhesive uses a polyurethane adhesive comprising component A and component B. Component A consists of polyurethane emulsion, thickener, curing agent, wetting agent and anti-hydrolysis agent. Component B uses cyclodextrin to embed the foaming agent, which slows down the foaming performance. Combined with the extrusion effect of the wetting agent, it improves the bonding strength.
Through slow-release foaming design and the use of wetting agents, the polyurethane film is in close contact with the fabric, significantly improving the bonding strength. It has excellent dry cleaning and washing resistance, with a peel strength between 31.8-36.9 N/3cm and still maintaining 25.6-33.3 N/3cm after washing.
Smart Images
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Figure BDA0005448924320000061
Abstract
Description
Technical Field
[0001] This application relates to the technical field of adhesives, and in particular to a polyurethane adhesive and its preparation method. Background Technology
[0002] Existing TPU products, or polyurethane products, are mostly bonded to clothing or shoe uppers using adhesives. However, adhesives have limited bonding strength, often resulting in weak adhesion and affecting the normal use of polyurethane products on clothing or shoe uppers. To address this, polyurethane adhesives have been used to bond polyurethane products to clothing or shoe uppers. Because polyurethane adhesives have a similar texture to polyurethane products, their adhesion has been greatly improved. However, due to the differences in materials between clothing and shoe uppers and polyurethane adhesives, the bonding strength still needs improvement. Summary of the Invention
[0003] To improve the bonding strength between polyurethane products and clothing or shoe uppers, this application provides a polyurethane adhesive and its preparation method.
[0004] In a first aspect, this application provides a polyurethane adhesive, which adopts the following technical solution: A polyurethane adhesive includes component A and component B. Component A comprises the following raw materials in parts by weight: 90-110 parts of polyurethane emulsion, 0.1-0.3 parts of thickener, 4-6 parts of curing agent, 0.7-1.3 parts of wetting agent, 1-3 parts of anti-hydrolysis agent, and 1.5-3.5 parts of adhesion promoter. Component B is prepared by mixing cyclodextrin and a foaming agent in water and then drying. The weight ratio of component A to component B is 100:(0.5-2).
[0005] By employing the above technical solution, dispersing the foaming agent and cyclodextrin in water allows the foaming agent to be encapsulated by the cyclodextrin. This means that after being thoroughly mixed with component A, the foaming agent exerts almost no foaming performance, achieving a similar slow-release effect. After bonding the materials, heating accelerates the release of the foaming agent, allowing it to exert its foaming properties. Once the polyurethane adhesive dries, its foaming performance is complete. Through the slow-release design of the foaming agent's foaming properties, the bubbles generated by the polyurethane adhesive after bonding, under maintained pressure, exert a compressive effect on both the polyurethane film and the fabric. Combined with the wetting agent, this ensures sufficient contact between the polyurethane adhesive and the fabric through compression, resulting in a tight bond between the polyurethane film and the fabric. This largely overcomes the problem of low bonding strength caused by the difference in material between clothing and shoe uppers and polyurethane materials, significantly improving the application potential of polyurethane materials in clothing or shoe uppers.
[0006] Preferably, the weight ratio of the cyclodextrin to the foaming agent is (3-5):2.
[0007] By adopting the above technical solution, the addition of cyclodextrin affects the encapsulation of the foaming agent, i.e., the sustained-release effect. The amount added affects the release rate of the foaming agent. If the release of the foaming agent is too fast or too slow, it will be detrimental to the bonding strength of the polyurethane adhesive.
[0008] Preferably, the foaming agent is an alkyl glycoside.
[0009] By adopting the above technical solution, alkyl glycosides have low surface tension, excellent foaming performance, rich and delicate foam film, no irritation to the human body, high safety in use, and can play a good foaming role in polyurethane adhesives.
[0010] Preferably, the alkyl glycoside is one or both of APG0810 and APG1214.
[0011] By adopting the above technical solutions, both alkyl glycosides exhibit superior foaming properties.
[0012] Preferably, the weight ratio of the cyclodextrin to the foaming agent is 2:1.
[0013] Preferably, the weight ratio of component A to component B is 100:1.
[0014] By adopting the above technical solution, when components A and B are added at a mass ratio of 100:1, the foaming performance of the foaming agent is more beneficial to the bonding performance of the polyurethane adhesive.
[0015] Preferably, the wetting agent is alkylphenol polyoxyethylene ether.
[0016] Preferably, the wetting agent is a mixture of alkylphenol polyoxyethylene ether and amino block silicone oil, wherein the mass ratio of alkylphenol polyoxyethylene ether to amino block silicone oil is 3:(1-3).
[0017] By adopting the above technical solution, the wetting agent can greatly reduce the surface tension between the polyurethane adhesive and the fabric, and by mixing alkylphenol polyoxyethylene ether and amino block silicone oil and using them as a wetting agent, the wetting effect of the wetting agent can be improved.
[0018] Secondly, this application provides a method for preparing a polyurethane adhesive, employing the following technical solution: A method for preparing a polyurethane adhesive, comprising the following steps: Component A: Mix and stir 22-28 parts by weight of polyether polyol, 14-18 parts by weight of diisocyanate and 30-35 parts by weight of epoxy resin, then add 28-35 parts by weight of acetone, heat to 80-90℃, and react at a constant temperature for 1.5-3 hours; lower the temperature by 5-10℃, then add 0.15-0.35 parts by weight of catalyst, 6-10 parts by weight of chain extender and 27-33 parts by weight of dimethylolpropionic acid, stir and react for 1.5-3 hours, add 28-35 parts by weight of acetone, and continue stirring and reacting for 1.5-3 hours, lower the temperature to 45-55℃, add 2.5-4 parts by weight of triethylamine and 35-45 parts by weight of deionized water, stir and emulsify, then remove acetone by vacuum distillation to obtain polyurethane emulsion; The polyurethane emulsion, thickener, curing agent, wetting agent, anti-hydrolysis agent and adhesion promoter are mixed and stirred evenly to obtain component A; Component B: Dissolve cyclodextrin in water, stir evenly, add foaming agent, stir at 150-300 r / min for 20-40 min, then stir at 2000-3000 r / min for 20-50 min, evaporate and concentrate, and dry to obtain component B; When using, simply mix components A and B according to their weight ratio.
[0019] By adopting the above technical solution, the preparation method of this application is simple and easy to operate, requires no modification to the equipment, has high tolerance for process parameters, and is suitable for mass production.
[0020] In summary, this application includes at least one of the following beneficial technical effects: 1. By dispersing the foaming agent and cyclodextrin in water, the foaming agent can be encapsulated by the cyclodextrin. Therefore, after being thoroughly mixed with component A, it exerts almost no foaming performance, achieving a similar slow-release effect. After bonding the materials, heating accelerates the release of the foaming agent, allowing it to exert its foaming performance. Once the polyurethane adhesive dries, its foaming performance is complete. Through the slow-release design of the foaming agent's foaming performance, the bubbles generated by the polyurethane adhesive after bonding, under maintained pressure, exert a compressive effect on both the polyurethane film and the fabric. Combined with the wetting agent, this ensures sufficient contact between the polyurethane adhesive and the fabric through compression, resulting in a tight bond between the polyurethane film and the fabric. This largely overcomes the problem of low bonding strength caused by the difference in material between clothing and shoe uppers and polyurethane materials, greatly improving the application potential of polyurethane materials in clothing or shoe uppers.
[0021] 2. The polyurethane adhesive prepared in this application can bond polyurethane films and fabrics well. The resulting adhesive layer samples exhibit excellent bonding strength, as well as superior dry cleaning and water washing resistance. Specifically, the peel strength of the adhesive layer samples before water washing is between 31.8 and 36.9 N / 3 cm, and after water washing, the peel strength can still reach 25.6 to 33.3 N / 3 cm. Detailed Implementation
[0022] The following provides a more detailed description of this application in conjunction with specific details.
[0023] raw material All raw materials used in the embodiments of this application were purchased commercially. Among them, the polyether polyol is model 9003-11-6, manufactured by Shandong Baiqian Chemical Co., Ltd.; the epoxy resin has CAS number 2100-22; the thickener is sodium polyacrylate, manufactured by Zhengzhou Jinhan Chemical Products Co., Ltd.; the curing agent is epoxy mercaptan curing agent, model GL1805; the anti-hydrolysis agent is model UN-03; the adhesion promoter is model PG-1458, manufactured by Guangzhou Duide Chemical Co., Ltd.; the alkylphenol polyoxyethylene ether is dodecylphenol polyoxyethylene ether, model OP-10; the cyclodextrin is β-cyclodextrin, industrial grade; and the amino block silicone oil is model COOL-1630, manufactured by Dongguan Jinda Textile Auxiliaries Co., Ltd. Example
[0024] Example 1 A polyurethane adhesive, comprising component A and component B, is prepared as follows: Component A: 25 kg of polyether polyol, 16 kg of 2,4-diisocyanate and 33 kg of epoxy resin are mixed and stirred, then 30 kg of acetone is added, heated to 85°C, and then reacted at a constant temperature for 2 h. The temperature was lowered to 80℃, then 0.25 kg of catalyst, 8 kg of chain extender, and 30 kg of dimethylolpropionic acid were added. The mixture was stirred for 2 hours, then 30 kg of acetone was added, and the reaction was continued for another 2 hours. The temperature was lowered to 50℃, then 3 kg of triethylamine and 40 kg of deionized water were added and stirred to emulsify. The acetone was then removed by vacuum distillation to obtain a polyurethane emulsion. The chain extender was butanediol, and the catalyst was a diethyltin dimer compound. Mix 100 kg of polyurethane emulsion, 0.2 kg of thickener, 5 kg of curing agent, 1 kg of wetting agent, 2 kg of anti-hydrolysis agent and 2.5 kg of adhesion promoter, and stir evenly to obtain component A; the wetting agent is alkylphenol polyoxyethylene ether. Component B: Add 20 kg of cyclodextrin to 50 kg of deionized water, stir evenly, then add 10 kg of foaming agent, stir at low speed of 200 r / min for 30 min, then stir at high speed of 2000 r / min for 30 min, then evaporate and concentrate, and dry to obtain component B; the foaming agent is alkyl glycoside, and the type of alkyl glycoside is APG0810. When using, add component A and component B in a mass ratio of 100:1, stir well, and then use.
[0025] Example 2 A polyurethane adhesive differs from Example 1 in that the amount of cyclodextrin added in its component B is 15 kg, while the remaining steps are the same as in Example 1.
[0026] Example 3 A polyurethane adhesive differs from Example 1 in that the amount of cyclodextrin added in its component B is 25 kg, while the remaining steps are the same as in Example 1.
[0027] Example 4 A polyurethane adhesive differs from Example 1 in that, in its application, components A and B are added at a mass ratio of 100:0.5, while the remaining steps are the same as in Example 1.
[0028] Example 5 A polyurethane adhesive differs from Example 1 in that, during application, components A and B are added in a mass ratio of 100:2, while the remaining steps are the same as in Example 1.
[0029] Example 6 A polyurethane adhesive differs from Example 1 in that, in its application, the wetting agent in component A is a mixture of alkylphenol polyoxyethylene ether and amino block silicone oil, with a mass ratio of alkylphenol polyoxyethylene ether to amino block silicone oil of 3:2, and the remaining steps are the same as in Example 1.
[0030] Comparative Example Comparative Example 1 A polyurethane adhesive differs from Example 1 in that it does not contain component B; that is, when applied, component B is replaced with an equal mass of component A, and the remaining steps are the same as in Example 1.
[0031] Comparative Example 2 A polyurethane adhesive differs from Example 1 in that its component B is a foaming agent. When applied, the mass ratio of component A to component B is 100:0.33, and the remaining steps are the same as in Example 1.
[0032] Comparative Example 3 A polyurethane adhesive differs from Example 1 in that its component B is a mixture of cyclodextrin and a foaming agent in a mass ratio of 2:1, i.e., the cyclodextrin and foaming agent are not dissolved by adding water, and the remaining steps are the same as in Example 1.
[0033] Performance testing Detection methods / test methods Polyurethane adhesives were prepared according to the preparation methods of Examples 1-6 and Comparative Examples 1-3. Then, polyurethane film and fabric adhesive layer samples were prepared according to the following preparation method. The samples were then tested according to the following testing method, and the test results are shown in Table 1.
[0034] Preparation of adhesive layer samples: A 1mm thick polyurethane film was uniformly coated with adhesive. The fabric was then attached to the bonding surface, pressed and left to stand for 10 minutes. The pressing was then maintained, the temperature was raised to 70℃, and the pressing was continued for 40 minutes to obtain the bonding layer sample. The fabric was 600D polyester fabric.
[0035] Washing performance test: In accordance with the requirements of JIS L0217 103, the washing machine is washed 10 times at 40℃, each time for 20 minutes; Dry cleaning resistance test: In accordance with the procedure standard of GB / T19981.2-2005, Professional maintenance, dry cleaning and wet cleaning of textiles, fabrics and garments, Part 2, Performance test of dry cleaning and ironing using tetrachloroethylene, 15 dry cleaning cycles. Peel strength test: The prepared adhesive layer sample was cut into 3cm wide strips and then its peel strength was tested.
[0036] Table 1. Detection results of Examples 1-6 and Comparative Examples 1-3 As can be seen from Examples 1-6, Comparative Examples 1-3, and the test data in Table 1, the polyurethane adhesive prepared in this application can bond polyurethane films and fabrics well. The adhesive layer samples obtained exhibit excellent bonding strength, as well as superior dry cleaning and water washing resistance. Specifically, the peel strength of the adhesive layer samples before water washing is between 31.8-36.9 N / 3cm, and after water washing, the peel strength can still reach 25.6-33.3 N / 3cm.
[0037] By dispersing the foaming agent and cyclodextrin in water, the foaming agent can be encapsulated by the cyclodextrin, thus barely exerting its foaming properties after being stirred evenly with component A, achieving a similar slow-release effect. After bonding the materials, heating can accelerate the release of the foaming agent, allowing it to exert its foaming properties. Once the polyurethane adhesive dries, its foaming properties are fully realized. Through the slow-release design of the foaming agent's foaming properties, the bubbles generated by the polyurethane adhesive after bonding, under maintained pressure, exert a compressive effect on both the polyurethane film and the fabric. Combined with the wetting agent, this ensures sufficient contact between the polyurethane adhesive and the fabric through compression, resulting in a tight bond between the polyurethane film and the fabric. This largely overcomes the problem of low bonding strength caused by the material difference between clothing and shoe uppers and polyurethane materials, greatly improving the application potential of polyurethane materials in clothing or shoe uppers. This is verified by the test data of Example 1 and Comparative Example 1. Meanwhile, in Comparative Example 2, if the foaming agent is added directly, its foaming performance occurs when components A and B are mixed. However, this results in more bubbles being generated on the bonding surface between the polyurethane adhesive and the fabric, reducing its bonding performance. Similarly, Comparative Example 3 follows the same principle. However, the test data of Comparative Example 3 shows that the addition of cyclodextrin helps to improve the bonding strength of the polyurethane adhesive. This is presumably because its molecular structure contains multiple hydroxyl groups, which increases the concentration of hydrogen bonds in the system.
[0038] The test data from Examples 1-3 show that the addition of cyclodextrin affects the encapsulation of the foaming agent, i.e., the sustained-release effect. Adding too little or too much cyclodextrin affects the release rate of the foaming agent. If the release of the foaming agent is too fast or too slow, it is not conducive to the bonding strength of the polyurethane adhesive.
[0039] Through Examples 1 and 4-5, when components A and B are added at a mass ratio of 100:1, the foaming properties of the foaming agent are more beneficial to the bonding properties of the polyurethane adhesive.
[0040] The test data from Examples 1 and 6 show that the wetting agent of this application can greatly reduce the surface tension between the polyurethane adhesive and the fabric. Furthermore, by mixing alkylphenol polyoxyethylene ether and amino block silicone oil and using them as a wetting agent, the wetting effect of the wetting agent can be improved.
[0041] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.
Claims
1. A polyurethane adhesive, characterized in that: It includes component A and component B. Component A includes the following raw materials in parts by weight: 90-110 parts of polyurethane emulsion, 0.1-0.3 parts of thickener, 4-6 parts of curing agent, 0.7-1.3 parts of wetting agent, 1-3 parts of anti-hydrolysis agent, and 1.5-3.5 parts of adhesion promoter; Component B is prepared by mixing cyclodextrin and a foaming agent in water and then drying. The weight ratio of component A to component B is 100:(0.5-2).
2. The polyurethane adhesive according to claim 1, characterized in that: The weight ratio of the cyclodextrin to the foaming agent is (3-5):
2.
3. The polyurethane adhesive according to claim 1, characterized in that: The foaming agent is an alkyl glycoside.
4. The polyurethane adhesive according to claim 3, characterized in that: The alkyl glycoside is one or both of APG0810 and APG1214.
5. The polyurethane adhesive according to claim 3, characterized in that: The weight ratio of the cyclodextrin to the foaming agent is 2:
1.
6. The polyurethane adhesive according to claim 5, characterized in that: The weight ratio of component A to component B is 100:
1.
7. The polyurethane adhesive according to claim 1, characterized in that: The wetting agent is alkylphenol polyoxyethylene ether.
8. The polyurethane adhesive according to claim 1, characterized in that: The wetting agent is a mixture of alkylphenol polyoxyethylene ether and amino block silicone oil, with a mass ratio of alkylphenol polyoxyethylene ether to amino block silicone oil of 3:(1-3).
9. A method for preparing the polyurethane adhesive according to any one of claims 1-8, characterized in that: It includes the following steps: Component A: Mix and stir 22-28 parts by weight of polyether polyol, 14-18 parts by weight of diisocyanate and 30-35 parts by weight of epoxy resin, then add 28-35 parts by weight of acetone, heat to 80-90℃, and then react at a constant temperature for 1.5-3 hours. Lower the temperature by 5-10℃, then add 0.15-0.35 parts by weight of catalyst, 6-10 parts by weight of chain extender and 27-33 parts by weight of dimethylolpropionic acid, stir and react for 1.5-3 hours, add 28-35 parts by weight of acetone, and continue stirring and reacting for 1.5-3 hours. Lower the temperature to 45-55℃, add 2.5-4 parts by weight of triethylamine and 35-45 parts by weight of deionized water, stir and emulsify, and then remove acetone by vacuum distillation to obtain polyurethane emulsion. Mix the polyurethane emulsion, thickener, curing agent, wetting agent, anti-hydrolysis agent and adhesion promoter, and stir evenly to obtain component A; Component B: Dissolve cyclodextrin in water, stir evenly, add foaming agent, stir at 150-300 r / min for 20-40 min, then stir at 2000-3000 r / min for 20-50 min, evaporate and concentrate, and dry to obtain component B; When using, simply mix components A and B according to their weight ratio.