Polyisocyanate adhesive with high adhesive property and production process thereof

Abstract

The invention discloses a polyisocyanate adhesive with high adhesive property and a production process thereof, and belongs to the technical field of polyisocyanate adhesives, and the production process comprises the following steps: modifying tert-butyl phenolic resin, preparing a polyisocyanate main agent, preparing a cross-linking agent and preparing the polyisocyanate adhesive. Through the modified treatment of the tert-butyl phenolic resin, the adaptability of the adhesive and the base material is remarkably improved, the debonding risk caused by poor interface bonding in long-term use is fundamentally reduced, and the bonding reliability of the product is directly improved. Through synergistic matching of different isocyanates, the bonding force between the base materials is enhanced, the bonding strength is effectively improved, and the requirement of a high-performance bonding scene is met.

Description

Technical Field

[0001] This invention relates to the field of polyisocyanate adhesive technology, specifically to a polyisocyanate adhesive with high bonding performance and its production process. Background Technology

[0002] Polyisocyanate adhesives are an important class of adhesives with unique chemical properties and bonding functions. Due to their adaptability and practicality in the field of material bonding, they have been widely used in key materials for connecting different substrates. Their bonding performance, stability in use and environmental safety directly affect the overall quality, reliability and service life of end products, and they play an indispensable role in industrial production and high-end manufacturing.

[0003] However, polyisocyanate adhesives prepared by existing technologies still have significant shortcomings, such as insufficient compatibility between the resin and the substrate, poor interfacial bonding stability, and a tendency to debond after long-term use. On the other hand, in traditional production processes, the total chlorine content of the product is relatively high, posing potential hazards to the environment and usage scenarios. At the same time, the viscosity control precision of the adhesive is insufficient. Too high a viscosity can lead to difficulties in coating and uneven distribution, while too low a viscosity will affect the bonding stability, resulting in problems such as low construction efficiency and fluctuations in bonding quality.

[0004] Based on this, the present invention designs a polyisocyanate adhesive with high bonding performance and its production process to solve the above problems. Summary of the Invention

[0005] To address the aforementioned shortcomings of existing technologies, this invention provides a polyisocyanate adhesive with high bonding performance and its production process, comprising the following steps: S1: By weight, add 10-15 parts of tert-butylphenolic resin to the reactor and stir; add 3-6 parts of propylene oxide dropwise, heat and continue stirring, add 1.5-3 parts of γ-aminopropyltriethoxysilane to the reactor and stir, add 0.05-0.15 parts of boron trifluoride ether and stir, cool and filter to obtain modified tert-butylphenolic resin; S2: By weight, add 5-8 parts of hexamethylene diisocyanate and 10-17 parts of isophorone diisocyanate to the reactor and stir. Add 45-55 parts of ethyl acetate-xylene mixed solvent. Increase the stirring rate and heat up. Add preheated modified tert-butylphenol resin dropwise and stir. Allow to cool naturally to obtain the polyisocyanate main agent. S3: By weight, add 12-18 parts of polypropylene glycol to the reactor and stir, add 10-15 parts of ethyl acetate and stir, add 0.1-0.3 parts of dibutyltin dilaurate to the reactor, increase the stirring rate, heat and stir, cool naturally, and filter to obtain the crosslinking agent; S4: Weigh out the polyisocyanate main agent and crosslinking agent in a mass ratio of 4-5:1, stir, let stand to degas, and cool to obtain a polyisocyanate adhesive with high bonding performance.

[0006] Furthermore, S1 specifically involves rinsing the reactor with deionized water 2-3 times, drying the reactor with hot air at 120-130℃, allowing it to cool naturally to room temperature, adding 10-15 parts by weight of tert-butylphenol resin to the reactor, and stirring at 150-200 r / min for 15-25 min. Add 3-6 parts of propylene oxide dropwise through a dropping funnel at a rate of 1-2 parts / h, increase the rotation speed to 200-300 r / min, raise the temperature to 63-76℃ at a rate of 5-8℃ / min, stir for 10-15 min, then raise the temperature to 80-95℃ at a rate of 3-5℃ / min, stir for 3-4 h, add 1.5-3 parts of γ-aminopropyltriethoxysilane to the reactor, stir for 5-10 min, add 0.05-0.15 parts of boron trifluoride ether, stir for 10-15 min, cool to 40-50℃ at a rate of 2-3℃ / min, and filter through a 100-200 mesh stainless steel filter to obtain modified tert-butylphenol resin.

[0007] Furthermore, S2 specifically involves: selecting a reactor equipped with a reflux condenser, cleaning it 2-3 times with anhydrous ethanol, purging it with dry compressed air at 110-120℃ for 30-40 minutes, preheating the cooling water in the reflux condenser to 30-35℃, and adding 5-8 parts by weight of hexamethylene diisocyanate and 10-17 parts by weight of isophorone diisocyanate to the reactor in sequence. First, stir at a rate of 100-150 r / min for 5-8 minutes, and then add 45-55 parts of ethyl acetate-xylene mixed solvent. Increase the stirring speed to 150-250 r / min, raise the temperature to 60-75℃ at a rate of 4-6℃ / min, stir for 15-20 min, preheat the modified tert-butylphenol resin to 45-50℃, add the preheated modified tert-butylphenol resin dropwise to the reactor at a rate of 1-2 parts / h through a dropping funnel, stir for 2-3 h, and allow it to cool naturally to 50-55℃ to obtain the polyisocyanate main agent.

[0008] Furthermore, S3 specifically involves: using a variable frequency stirred reactor, cleaning it 2-3 times with anhydrous ethanol, continuously purging it with dry hot air at 105-115℃ for 25-35 minutes, and allowing it to cool naturally to room temperature. Then, add 12-18 parts by weight of polypropylene glycol to the reactor, stirring at 150-180 r / min for 8-10 minutes. Next, add 10-15 parts of ethyl acetate at 2-3 parts / min, stirring for 5-8 minutes. Finally, add 0.1-0.3 parts of dibutyltin dilaurate to the reactor, increasing the stirring speed to 180-280 r / min and stirring for 3-5 minutes. Then, raise the temperature to 50-60℃ at a rate of 3-5℃ / min, stirring for 1.5-2 hours, allowing it to cool naturally to 40-45℃, and filter through a 150-200 mesh stainless steel filter to obtain the crosslinking agent.

[0009] Furthermore, S4 specifically involves: allowing the polyisocyanate main agent and crosslinking agent to stand at 20-25℃ for 30-40 minutes; weighing the polyisocyanate main agent and crosslinking agent separately at a mass ratio of 4-5:1; stirring at 150-200 r / min for 5-8 minutes; increasing the stirring speed to 200-300 r / min; stirring at 20-25℃ for 30-45 minutes; allowing to stand for degassing for 20-30 minutes; and cooling to 15-20℃ at a rate of 1-2℃ / min to obtain a polyisocyanate adhesive with high bonding performance.

[0010] A polyisocyanate adhesive with high bonding performance prepared according to the aforementioned production process.

[0011] Compared with the prior art, the beneficial effects of this invention are as follows: 1. This solution significantly improves the compatibility between the adhesive and the substrate by modifying the adhesive with tert-butylphenol resin. This fundamentally reduces the risk of debonding caused by poor interfacial bonding during long-term use, directly improving the bonding reliability of the product. The synergistic combination of different isocyanates strengthens the bonding force between substrates, effectively increasing the adhesive strength and meeting the requirements of high-performance bonding scenarios.

[0012] 2. This invention, through the modification of tert-butylphenol resin and the combined use of specific crosslinking agent raw materials, significantly reduces the total chlorine content of the product to ≤0.03%, improving the product's environmental compliance and reducing the adverse effects of harmful impurities on the environment and usage scenarios. Simultaneously, it precisely controls the viscosity of the adhesive to remain stable between 1500-1800 mPa·s, placing it within a suitable range for application. This ensures smooth application and provides a foundation for stable bonding, avoiding application difficulties and bonding quality fluctuations caused by inconsistent viscosity. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0014] Example 1: This example discloses a production process for a polyisocyanate adhesive with high bonding performance, including the following steps: S1: Rinse the reactor twice with deionized water, dry the reactor with hot air at 120°C, and let it cool naturally to room temperature. Add 10 parts by weight of tert-butylphenol resin to the reactor and stir at 150 r / min for 15 min. Add 3 parts of propylene oxide dropwise through a dropping funnel at a rate of 1 part / h, increase the rotation speed to 200 r / min, raise the temperature to 63°C at a rate of 5°C / min, stir for 10 min, then raise the temperature to 80°C at a rate of 3°C / min, stir for 3 h, add 1.5 parts of γ-aminopropyltriethoxysilane (KH550) to the reactor, stir for 5 min, add 0.05 parts of boron trifluoride ether, stir for 10 min, lower the temperature to 40°C at a rate of 2°C / min, and filter through a 100-mesh stainless steel filter to obtain modified tert-butylphenol resin; S2: Select a reactor equipped with a reflux condenser, clean it twice with anhydrous ethanol, purge it with dry compressed air at 110°C for 30 minutes, preheat the cooling water in the reflux condenser to 30°C, and add 5 parts by weight of hexamethylene diisocyanate and 10 parts by weight of isophorone diisocyanate to the reactor in sequence. Stir at a rate of 100 r / min for 5 minutes, and then add 45 parts of ethyl acetate-xylene mixed solvent (the mass ratio of ethyl acetate to xylene is 1:1.2). Increase the stirring rate to 150 r / min, raise the temperature to 60℃ at a rate of 4℃ / min, stir for 15 min, preheat the modified tert-butylphenol resin to 45℃, and add the preheated modified tert-butylphenol resin dropwise to the reactor at a rate of 1 part / h through a dropping funnel (with a heat-insulating jacket, jacket temperature 45℃), stir for 2 h, and allow it to cool naturally to 50℃ to obtain the polyisocyanate main agent; S3: A variable frequency stirred reactor was selected, cleaned twice with anhydrous ethanol, and continuously purged with dry hot air at 105°C for 25 minutes. After naturally cooling to room temperature, 12 parts by weight of polypropylene glycol were added to the reactor and stirred at 150 r / min for 8 minutes. 10 parts of ethyl acetate were added at 2 parts / min and stirred for 5 minutes. 0.1 parts of dibutyltin dilaurate were added to the reactor, and the stirring speed was increased to 180 r / min and stirred for 5 minutes. The temperature was increased to 50°C at a rate of 3°C / min and stirred for 1.5 hours. After naturally cooling to 40°C, the mixture was filtered through a 150-mesh stainless steel filter to obtain the crosslinking agent. S4: Let the polyisocyanate main agent and crosslinking agent stand at 20℃ for 30 min. Weigh the polyisocyanate main agent and crosslinking agent at a mass ratio of 4:1. Stir at 150 r / min for 5 min. Increase the stirring speed to 200 r / min. Stir at 20℃ for 30 min and let stand to degas for 20 min. Cool down to 15℃ at a rate of 1℃ / min to obtain a polyisocyanate adhesive with high bonding performance.

[0015] Example 2: This example discloses a production process for a polyisocyanate adhesive with high bonding performance, including the following steps: S1: Rinse the reactor three times with deionized water, dry the reactor with hot air at 130°C, and let it cool naturally to room temperature. Add 15 parts by weight of tert-butylphenol resin to the reactor and stir at 200 r / min for 25 min. Add 6 parts of propylene oxide dropwise through a dropping funnel at a rate of 2 parts / h, increase the rotation speed to 300 r / min, raise the temperature to 76°C at a rate of 8°C / min, stir for 15 min, then raise the temperature to 95°C at a rate of 5°C / min, stir for 4 h, add 3 parts of γ-aminopropyltriethoxysilane (KH550) to the reactor, stir for 10 min, add 0.15 parts of boron trifluoride ether, stir for 15 min, lower the temperature to 50°C at a rate of 3°C / min, and filter through a 200-mesh stainless steel filter to obtain modified tert-butylphenol resin; S2: Select a reactor equipped with a reflux condenser, clean it three times with anhydrous ethanol, purge it with dry compressed air at 120°C for 40 minutes, preheat the cooling water in the reflux condenser to 35°C, and add 8 parts by weight of hexamethylene diisocyanate and 17 parts by weight of isophorone diisocyanate to the reactor in sequence. Stir at a rate of 150 r / min for 8 minutes, and then add 55 parts of ethyl acetate-xylene mixed solvent (the mass ratio of ethyl acetate to xylene is 1:1.5). Increase the stirring rate to 250 r / min, raise the temperature to 75°C at a rate of 6°C / min, stir for 20 min, preheat the modified tert-butylphenol resin to 50°C, and add the preheated modified tert-butylphenol resin dropwise to the reactor at a rate of 2 parts / h through a dropping funnel (with a heat-insulating jacket, jacket temperature 50°C), stir for 3 h, and allow it to cool naturally to 55°C to obtain the polyisocyanate main agent; S3: A variable frequency stirred reactor was selected, cleaned three times with anhydrous ethanol, and continuously purged with dry hot air at 115°C for 35 minutes. After naturally cooling to room temperature, 18 parts by weight of polypropylene glycol were added to the reactor and stirred at 180 r / min for 10 minutes. 15 parts of ethyl acetate were added at 3 parts / min and stirred for 8 minutes. 0.3 parts of dibutyltin dilaurate were added to the reactor, and the stirring speed was increased to 280 r / min. After stirring for 5 minutes, the temperature was increased to 60°C at a rate of 5°C / min and stirred for 2 hours. After naturally cooling to 45°C, the mixture was filtered through a 200-mesh stainless steel filter to obtain the crosslinking agent. S4: Let the polyisocyanate main agent and crosslinking agent stand at 25°C for 40 min. Weigh the polyisocyanate main agent and crosslinking agent at a mass ratio of 5:1. Stir at 200 r / min for 8 min. Increase the stirring speed to 300 r / min. Stir at 25°C for 45 min. Let stand to degas for 30 min. Cool down to 20°C at a rate of 2°C / min to obtain a polyisocyanate adhesive with high bonding performance.

[0016] Example 3: This example discloses a production process for a polyisocyanate adhesive with high bonding performance, characterized by the following steps: S1: Rinse the reactor three times with deionized water, dry the reactor with hot air at 126°C, and allow it to cool naturally to room temperature. Add 13 parts by weight of tert-butylphenol resin to the reactor and stir at 185 r / min for 21 min. 4.2 parts of propylene oxide were added dropwise through a dropping funnel at a rate of 1.4 parts / h, the rotation speed was increased to 270 r / min, the temperature was increased to 67℃ at a rate of 6℃ / min, and stirred for 12 min. Then the temperature was increased to 86℃ at a rate of 4℃ / min and stirred for 4 h. 2.3 parts of γ-aminopropyltriethoxysilane (KH550) were added to the reactor and stirred for 6 min. 0.11 parts of boron trifluoride ether were added and stirred for 11 min. The temperature was decreased to 43℃ at a rate of 2℃ / min and filtered through a 150-mesh stainless steel filter to obtain modified tert-butylphenol resin. S2: Select a reactor equipped with a reflux condenser, clean it twice with anhydrous ethanol, purge it with dry compressed air at 116°C for 35 minutes, preheat the cooling water in the reflux condenser to 32°C, and add 6.5 parts by weight of hexamethylene diisocyanate and 14 parts by weight of isophorone diisocyanate to the reactor in sequence. Stir at a rate of 120 r / min for 6 minutes, and then add 51 parts of ethyl acetate-xylene mixed solvent (the mass ratio of ethyl acetate to xylene is 1:1.3). The stirring rate was increased to 220 r / min, the temperature was increased to 71℃ at a rate of 5℃ / min, and the mixture was stirred for 19 min. The modified tert-butylphenol resin was preheated to 47℃ and added dropwise to the reactor at a rate of 1.6 parts / h through a dropping funnel (with a heat-insulating jacket, the jacket temperature was 47℃). The mixture was stirred for 2 h and then allowed to cool naturally to 52℃ to obtain the polyisocyanate main agent. S3: A variable frequency stirred reactor was selected, cleaned three times with anhydrous ethanol, and continuously purged with dry hot air at 112°C for 30 minutes. After naturally cooling to room temperature, 14 parts by weight of polypropylene glycol were added to the reactor and stirred at 165 r / min for 9 minutes. 12 parts of ethyl acetate were added at 2.3 parts / min and stirred for 7 minutes. 0.22 parts of dibutyltin dilaurate were added to the reactor, the stirring speed was increased to 220 r / min, and stirred for 5 minutes. The temperature was increased to 58°C at a rate of 4°C / min and stirred for 2 hours. After naturally cooling to 42°C, the mixture was filtered through a 200-mesh stainless steel filter to obtain the crosslinking agent. S4: Let the polyisocyanate main agent and crosslinking agent stand at 22℃ for 34 min. Weigh the polyisocyanate main agent and crosslinking agent at a mass ratio of 4.6:1. Stir at 170 r / min for 6 min. Increase the stirring speed to 250 r / min. Stir at 25℃ for 41 min. Let stand to degas for 25 min. Cool down to 18℃ at a rate of 2℃ / min to obtain a polyisocyanate adhesive with high adhesion performance.

[0017] Comparative Example 1: The difference between this comparative example and Example 3 is that the tert-butylphenol resin was not modified.

[0018] Comparative Example 2: The difference between this comparative example and Example 3 is that in S3, polypropylene glycol and dibutyltin dilaurate are replaced with equal amounts of polyethylene glycol and dibutyltin dichloride.

[0019] Comparative Example 3: This comparative example differs from Example 3 in that the tert-butylphenol resin was not modified and in S3, polypropylene glycol and dibutyltin dilaurate were replaced with equal amounts of polyethylene glycol and dibutyltin dichloride.

[0020] Experimental Example 1: The tensile shear strength (MPa) of the polyisocyanate adhesive with high bonding performance prepared according to GB / T 7124-2008 was tested.

[0021] Experimental Example 2: The total chlorine content (%) of the polyisocyanate adhesive with high bonding performance prepared by this invention was measured according to GB 12009.1-1989.

[0022] Experimental Example 3: The viscosity (in mPa·s) of the polyisocyanate adhesive with high bonding performance prepared according to GB / T 2794-2022 was measured.

[0023] The results are shown in the table below:

[0024] As shown in the table above, the strength of Comparative Example 1 (unmodified tert-butylphenol resin), Comparative Example 2 (replaced crosslinking agent), and Comparative Example 3 (both unmodified tert-butylphenol resin and replaced crosslinking agent) all decreased, proving that the combination of the two can significantly enhance the bonding force of the substrate, thereby improving the adhesion performance; the total chlorine content of Comparative Example 2 and Comparative Example 3 increased sharply, proving that the selection of crosslinking agent raw materials directly affects the total chlorine content.

[0025] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A production process of a polyisocyanate adhesive having high bonding properties, characterized by, Comprising the following steps: S1: by weight parts, 10-15 parts of tertiary butyl phenolic resin is added to the reaction kettle stirring; drop 3-6 parts of propylene oxide, continue to stir, add 1.5-3 parts of gamma-aminopropyl triethoxysilane to the kettle stirring, add 0.05-0.15 parts of boron trifluoride ether stirring, after cooling, filtration, to obtain modified tertiary butyl phenolic resin; S2: by weight parts, 5-8 parts of hexamethylene diisocyanate and 10-17 parts of isophorone diisocyanate are added to the reaction kettle stirring, 45-55 parts of ethyl acetate-xylene mixed solvent is added; increase the stirring speed and temperature, drop the preheated modified tertiary butyl phenolic resin stirring, natural cooling to obtain polyisocyanate main agent; S3: by weight parts, 12-18 parts of polypropylene glycol is added to the reaction kettle stirring, 10-15 parts of ethyl acetate is added to the kettle stirring, 0.1-0.3 parts of dibutyltin dilaurate is added to the kettle, the stirring speed is increased, the temperature is increased, and the temperature is decreased, and the crosslinking agent is obtained by filtration; S4: the polyisocyanate main agent and the crosslinking agent are weighed in a ratio of 4-5:1, stirred and deaerated, and cooled to obtain a polyisocyanate adhesive with high bonding performance.

2. The production process of polyisocyanate adhesive having high bonding properties according to claim 1, characterized by, S1 is: the reaction kettle is washed with deionized water for 2-3 times, hot air of 120-130 DEG C is introduced into the reaction kettle for drying treatment, and the temperature is naturally cooled to room temperature. By weight parts, 10-15 parts of tertiary butyl phenolic resin is added to the reaction kettle, and stirred at 150-200 r / min for 15-25 min; Through the dropping funnel, 3-6 parts of propylene oxide is added at a rate of 1-2 parts / h, the speed is increased to 200-300 r / min, the temperature is increased to 63-76 DEG C at a rate of 5-8 DEG C / min, and stirred for 10-15 min. The temperature is increased to 80-95 DEG C at a rate of 3-5 DEG C / min, and stirred for 3-4 h. 1.5-3 parts of gamma-aminopropyl triethoxysilane is added to the kettle, stirred for 5-10 min, 0.05-0.15 parts of boron trifluoride ether is added, stirred for 10-15 min, and cooled to 40-50 DEG C at a rate of 2-3 DEG C / min. Filter through a 100-200 mesh stainless steel filter screen to obtain modified tertiary butyl phenolic resin.

3. The production process of polyisocyanate adhesive having high bonding properties according to claim 1, characterized by, S2 is: a reaction kettle with reflux condenser is selected, washed with anhydrous ethanol for 2-3 times, and dried compressed air of 110-120 DEG C is introduced for 30-40 min. The cooling water in the reflux condenser is preheated to 30-35 DEG C. By weight parts, 5-8 parts of hexamethylene diisocyanate and 10-17 parts of isophorone diisocyanate are added to the reaction kettle, first stirred at a speed of 100-150 r / min for 5-8 min, and then 45-55 parts of ethyl acetate-xylene mixed solvent is added; The stirring rate is increased to 150-250 r / min, the temperature is increased to 60-75℃ at a rate of 4-6℃ / min, the modified tertiary butyl phenolic aldehyde resin is preheated to 45-50℃, the preheated modified tertiary butyl phenolic aldehyde resin is added to the reaction kettle at a rate of 1-2 parts / h through a dropping funnel, stirring is performed for 2-3 h, and the temperature is naturally decreased to 50-55℃, thereby obtaining the polyisocyanate main agent.

4. The production process of polyisocyanate adhesive having high bonding properties according to claim 1, characterized by, S3 specifically comprises: a frequency conversion stirring reaction kettle is selected, the kettle is cleaned with anhydrous ethanol for 2-3 times, dry hot air at 105-115℃ is introduced for continuous blowing for 25-35 min, and the kettle is naturally cooled to room temperature; 12-18 parts of polypropylene glycol are added to the kettle, stirring is performed at a rate of 150-180 r / min for 8-10 min, 10-15 parts of ethyl acetate are added at a rate of 2-3 parts / min, stirring is performed for 5-8 min, 0.1-0.3 parts of dibutyltin dilaurate is added to the kettle, the stirring rate is increased to 180-280 r / min, stirring is performed for 3-5 min, the temperature is increased to 50-60℃ at a rate of 3-5℃ / min, stirring is performed for 1.5-2 h, the temperature is naturally decreased to 40-45℃, and the mixture is filtered through a 150-200 mesh stainless steel filter screen, thereby obtaining the crosslinking agent.

5. The production process of polyisocyanate adhesive having high bonding properties according to claim 1, characterized by, S4 specifically comprises: the polyisocyanate main agent and the crosslinking agent are statically placed at 20-25℃ for 30-40 min, stirring is performed at 150-200 r / min for 5-8 min, the stirring rate is increased to 200-300 r / min, the mixture is statically placed for 20-30 min after stirring at 20-25℃ for 30-45 min, the temperature is decreased to 15-20℃ at a rate of 1-2℃ / min, and the polyisocyanate glue with high bonding performance is obtained.

6. The production process of polyisocyanate adhesive having high bonding properties according to claim 5, characterized by, The mass ratio of the polyisocyanate main agent to the crosslinking agent is 4-5:

1.

7. The production process of polyisocyanate adhesive having high bonding properties according to claim 5, characterized by, The cooling rate is 1-2℃ / min.

8. A polyisocyanate glue with high bonding performance prepared by the production process according to any one of claims 1-7.

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