Preparation method of a high-temperature resistant water-based environmental protection glue

Abstract

The invention discloses a preparation method of a high-temperature resistant water-based environmental protection glue, belonging to the technical field of water-based glue preparation, which comprises the following steps: S1-1, preparing materials according to the following mass percentage components: 13-15% of modified polyurethane prepolymer, 7.5-9.6% of modified acrylic resin, 5-7% of polyvinylidene chloride, 4-5% of coupling agent, 3-5% of polyvinyl alcohol, 7-12% of heat-resistant monomer, 3-4% of silicon dioxide powder, 1-3% of alumina powder, and the balance being deionized water; S1-2, reacting the modified polyurethane prepolymer, modified acrylic resin, polyvinylidene chloride and deionized water in a reaction kettle; S1-3, adding the coupling agent, polyvinyl alcohol, silicon dioxide powder and alumina powder, and continuing the reaction to obtain the water-based environmental protection glue. The water-based environmental protection glue prepared by the invention not only has a high viscosity, but also has good high-temperature resistance, and can maintain a stable viscosity under long-term exposure to sunlight or high-temperature environment. Compared with solvent-based glue, the water-based environmental protection glue of the invention has less volatile harmful gases.

Description

Technical Field

[0001] The present invention relates to the technical field of the preparation of water-based adhesives, and particularly to a preparation method of a high-temperature resistant water-based environmental protection adhesive. Background Art

[0002] Water-based adhesives, as the name implies, are adhesives that use water as the main solvent. They usually contain natural or synthetic macromolecular substances and use water as the solvent or dispersant. Compared with traditional organic solvent adhesives, such adhesives have the advantages of environmental protection, safety, easy operation and high efficiency, and thus have been widely used in many fields.

[0003] Water-based adhesives can be classified according to different criteria. According to the material source, they can be divided into natural water-based adhesives and synthetic water-based adhesives. Natural water-based adhesives are mainly composed of natural substances such as plant collagen, natural gums and sodium alginate, while synthetic water-based adhesives are obtained through chemical synthesis, and the main components include polyester, polyurethane and synthetic collagen, etc.

[0004] The viscosity of existing water-based adhesives decreases under long-term exposure to sunlight or high-temperature environments. The high-temperature resistance of solvent-based adhesives is higher than that of water-based adhesives in terms of viscosity, but the VOCs they volatilize are high. Therefore, there is a need for an environmentally friendly water-based adhesive with high temperature resistance. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a preparation method of a high-temperature resistant water-based environmental protection adhesive.

[0006] The technical solution of the present invention is: a preparation method of a high-temperature resistant water-based environmental protection adhesive, comprising the following steps:

[0007] S1-1. Prepare materials according to the following mass percentage components: 13-15% modified polyurethane prepolymer, 7.5-9.6% modified acrylic resin, 5-7% polyvinylidene chloride, 4-5% coupling agent, 3-5% polyvinyl alcohol, 7-12% heat-resistant monomer, 3-4% silicon dioxide powder, 1-3% aluminum oxide powder, and the balance is deionized water;

[0008] S1-2. Add the above-mentioned deionized water to a reaction kettle, heat it to 70-80°C and keep it at a constant temperature, then add the modified polyurethane prepolymer, modified acrylic resin, and polyvinylidene chloride to the reaction kettle and mix and stir; the stirring speed is 120 r / min, and the stirring time is 4-6 h. Ultrasonic treatment is carried out during stirring. After stirring is completed, add the heat-resistant monomer and polyvinyl alcohol according to the said parts by weight and continue to stir for 2-4 h to obtain a colloidal solution;

[0009] S1-3. Continue to add a coupling agent, silica powder, and alumina powder to the reaction kettle containing the colloidal solution, heat up to 80 - 90 °C, continuously stir for 2 - 3 h, then cool to room temperature, perform vacuum degassing treatment, and then carry out filling to obtain the water-based environmental protection glue.

[0010] Further, the heat-resistant monomer is vinylpyrrolidone and / or methyl methacrylate.

[0011] Further, the coupling agent is prepared by mixing 3-aminopropyltriethoxysilane and γ-glycidyletheroxypropyltrimethoxysilane in a mass ratio of 1:1.

[0012] Further, the preparation method of the modified polyurethane prepolymer in step S1-1 includes the following steps:

[0013] S2-1. Drop the polyester polyol into the reaction kettle containing isocyanate, stir under the protection of a nitrogen atmosphere, the stirring speed is 80 - 100 r / min, the reaction temperature is 70 - 90 °C, and the reaction duration is 5 - 8 h to obtain a polyurethane prepolymer; the molar ratio of the polyester polyol to the isocyanate is 2:1;

[0014] S2-2. Lower the temperature of the reaction kettle to 40 - 50 °C, then continue to add a modifier to the reaction kettle, the addition amount of the modifier is 20 - 25% of the total mass of the polyurethane prepolymer, keep the stirring speed unchanged, continuously stir for 4 - 6 h, after the stirring is completed, add a chain extender to the reaction kettle for chain extension reaction, the chain extender is diethylenetriamine, the addition amount of the chain extender is 10 - 15% of the total mass of the polyurethane prepolymer, keep the stirring speed unchanged, and continuously stir for 2 - 5 h to obtain the modified polyurethane prepolymer.

[0015] Further, the preparation method of the modifier is: put γ-aminopropyltriethoxysilane and nano-SiO₂ into the reaction kettle, the dosage of γ-aminopropyltriethoxysilane is 1 - 5 wt% of nano-SiO 2 , the temperature of the reaction kettle is 80 - 95 °C, the reaction duration is 5 - 8 h, the product obtained after the reaction is washed to remove the unreacted γ-aminopropyltriethoxysilane, and then vacuum dried to obtain the modifier.

[0016] Further, the preparation method of the modified acrylic resin includes the following steps:

[0017] S3-1. Add acrylate monomer, crosslinking agent, and initiator into the reaction kettle according to the mass ratio of 87:5:3. Use argon as the protective gas for polymerization reaction. The pressure in the reaction kettle is 5 - 10 Pa relative to atmospheric pressure, the temperature of the reaction kettle is 60 - 70 °C, the reaction duration is 5 - 10 h, the stirring speed is 80 - 100 r / min. After the reaction is completed, an acrylic polymer is obtained.

[0018] S3-2. Heat the reaction kettle to 80 - 90 °C, then add the modifier and emulsifier into the reaction kettle. The addition amount of the modifier accounts for 5 - 10% of the total mass of the acrylic polymer, and the addition amount of the emulsifier accounts for 3 - 7% of the total mass of the acrylic polymer. Continue stirring for 4 - 5 h. Vacuum the reaction kettle to 7 - 15 Pa and keep it for 2 - 3 h to obtain a modified acrylic resin.

[0019] Furthermore, the emulsifier uses allyloxy nonylphenol polyoxyethylene ether bisphosphate, the crosslinking agent uses glycerol acrylate, the initiator uses azobisisobutyronitrile, and the modifier uses epoxy resin.

[0020] The beneficial effects of the present invention are:

[0021] The water-based environmental protection glue prepared by the present invention not only has a high viscosity but also good high-temperature resistance. It can maintain a stable viscosity under long-term exposure to sunlight or in a high-temperature environment. Compared with solvent-based glue, the water-based environmental protection glue of the present invention has less volatile harmful gases and can be used in high-temperature environments such as solar photovoltaic modules and automotive headlight modules. Specific embodiments

[0022] Example 1:

[0023] A preparation method of a high-temperature resistant water-based environmental protection glue includes the following steps:

[0024] S1-1. Prepare materials according to the following mass percentage components: 13% modified polyurethane prepolymer, 7.5% modified acrylic resin, 5% polyvinylidene chloride, 4% coupling agent, 3% polyvinyl alcohol, 7% heat-resistant monomer, 3% silica powder, 1% alumina powder, and the balance is deionized water; the average particle sizes of the silica powder and the alumina powder are both 10 μm; the heat-resistant monomer uses vinylpyrrolidone; the coupling agent is prepared by mixing 3-aminopropyltriethoxysilane and γ-glycidyletheroxypropyltrimethoxysilane according to the mass ratio of 1:1.

[0025] S1-2. Add the above deionized water into the reaction kettle, heat it to 70 °C and keep it at a constant temperature. Then add the modified polyurethane prepolymer, modified acrylic resin, and polyvinylidene chloride into the reaction kettle and stir them; the stirring speed is 120 r / min, the stirring duration is 4 h, and ultrasonic treatment is carried out during stirring. The ultrasonic frequency of the ultrasonic treatment is 20 Hz, and the ultrasonic wavelength is 0.06 mm. After stirring is completed, add heat-resistant monomers and polyvinyl alcohol by weight parts and continue to stir for 2 h to obtain a colloidal solution;

[0026] S1-3. Continue to add a coupling agent, silicon dioxide powder, and alumina powder into the reaction kettle containing the colloidal solution, heat it up to 80 °C, and continuously stir for 2 h. Then cool it to room temperature of 28 °C and carry out vacuum degassing treatment. The vacuum degassing treatment is to evacuate the reaction kettle to 4 Pa and keep it for 2 h. Then carry out filling to obtain the water-based environmental protection glue.

[0027] The preparation method of the modified polyurethane prepolymer in step S1-1 includes the following steps:

[0028] S2-1. Drop the polyester polyol into the reaction kettle containing isocyanate, stir it under the protection of nitrogen atmosphere, the stirring speed is 80 r / min, the reaction temperature is 70 °C, and the reaction duration is 5 h to obtain a polyurethane prepolymer; the molar ratio of polyester polyol to isocyanate is 2:1;

[0029] S2-2. Lower the temperature of the reaction kettle to 40 °C, then continue to add a modifier into the reaction kettle. The addition amount of the modifier is 20% of the total mass of the polyurethane prepolymer. Keep the stirring speed unchanged and continuously stir for 4 h. After stirring is completed, add a chain extender into the reaction kettle for chain extension reaction. The chain extender uses diethylenetriamine, and the addition amount of the chain extender is 10% of the total mass of the polyurethane prepolymer. Keep the stirring speed unchanged and continuously stir for 2 h to obtain the modified polyurethane prepolymer.

[0030] The preparation method of the modifier is: Mix γ-aminopropyltriethoxysilane and nano-SiO₂ and put them into the reaction kettle. The dosage of γ-aminopropyltriethoxysilane is 1 wt% of nano-SiO 2 After the reaction for 5 h at a reaction kettle temperature of 80 °C, the obtained product is washed to remove the unreacted γ-aminopropyltriethoxysilane, and then vacuum dried to obtain the modifier.

[0031] The preparation method of the modified acrylic resin includes the following steps:

[0032] S3-1. Add acrylate monomer, crosslinking agent, and initiator into the reaction kettle according to the mass ratio of 87:5:3. Use argon as the protective gas to carry out the polymerization reaction. The pressure in the reaction kettle is 5 Pa relative to the atmospheric pressure, the temperature of the reaction kettle is 60 °C, the reaction duration is 5 h, the stirring speed is 80 r / min. After the reaction is completed, an acrylic polymer is obtained.

[0033] S3-2. Heat the reaction kettle to 80 °C, then add the modifier and emulsifier into the reaction kettle. The addition amount of the modifier accounts for 5% of the total mass of the acrylic polymer, and the addition amount of the emulsifier accounts for 3% of the total mass of the acrylic polymer. Continue to stir for 4 h. Vacuumize the reaction kettle to 7 Pa and keep it for 2 h to obtain a modified acrylic resin.

[0034] The emulsifier is allyloxy nonylphenol polyoxyethylene ether bisphosphate, the crosslinking agent is glycerol acrylate, the initiator is azobisisobutyronitrile, and the modifier is epoxy resin.

[0035] Example 2:

[0036] A preparation method of a high-temperature resistant water-based environmental protection glue, comprising the following steps:

[0037] S1-1. Prepare materials according to the following mass percentage components: 13.5% modified polyurethane prepolymer, 8.6% modified acrylic resin, 5.5% polyvinylidene chloride, 4.5% coupling agent, 3.5% polyvinyl alcohol, 7.5% heat-resistant monomer, 3.2% silica powder, 1.5% alumina powder, and the balance is deionized water; the average particle sizes of the silica powder and the alumina powder are both 13 μm; the heat-resistant monomer is methyl methacrylate; the coupling agent is prepared by mixing 3-aminopropyltriethoxysilane and γ-glycidyletheroxypropyltrimethoxysilane according to the mass ratio of 1:1.

[0038] S1-2. Add the above-mentioned deionized water into the reaction kettle and heat it to 77 °C to keep it constant. Then add the modified polyurethane prepolymer, modified acrylic resin, and polyvinylidene chloride into the reaction kettle and mix and stir; the stirring speed is 120 r / min, the stirring duration is 5.5 h, and ultrasonic treatment is carried out during stirring. The ultrasonic frequency of the ultrasonic treatment is 35 Hz, and the ultrasonic wavelength is 0.3 mm; after the stirring is completed, add the heat-resistant monomer and polyvinyl alcohol by weight and continue to stir for 2.5 h to obtain a colloidal solution.

[0039] S1-3. Continue to add the coupling agent, silica powder, and alumina powder into the reaction kettle containing the colloidal solution, heat it to 88 °C, and continuously stir for 2.5 h. Then cool it to room temperature of 24 °C and carry out vacuum defoaming treatment. The vacuum defoaming treatment is to vacuumize the reaction kettle to 5 Pa and keep it for 2.5 h; then carry out filling to obtain the water-based environmental protection glue.

[0040] The preparation method of the modified polyurethane prepolymer in step S1-1 includes the following steps:

[0041] S2-1. Drop the polyester polyol into the reaction kettle containing isocyanate, stir under the protection of nitrogen atmosphere, the stirring speed is 88 r / min, the reaction temperature is 75 °C, and the reaction duration is 5.5 h to obtain a polyurethane prepolymer; the molar ratio of polyester polyol to isocyanate is 2:1.

[0042] S2-2. Lower the temperature of the reaction kettle to 45 °C, then continue to add a modifier to the reaction kettle. The addition amount of the modifier is 23% of the total mass of the polyurethane prepolymer. Keep the stirring speed unchanged and stir continuously for 4.5 h. After the stirring is completed, add a chain extender to the reaction kettle for chain extension reaction. The chain extender uses diethylenetriamine, and the addition amount of the chain extender is 13% of the total mass of the polyurethane prepolymer. Keep the stirring speed unchanged and stir continuously for 3 h to obtain a modified polyurethane prepolymer.

[0043] The preparation method of the modifier is: Mix γ-aminopropyltriethoxysilane and nano-SiO2 and put them into a reaction kettle. The dosage of γ-aminopropyltriethoxysilane is 3 wt% of nano-SiO 2 . The temperature of the reaction kettle is 90 °C, and the reaction duration is 6 h. The product obtained after the reaction is washed to remove unreacted γ-aminopropyltriethoxysilane, and then vacuum dried to obtain the modifier.

[0044] The preparation method of the modified acrylic resin includes the following steps:

[0045] S3-1. Add acrylate monomer, crosslinking agent, and initiator to the reaction kettle according to the mass ratio of 87:5:3, use argon as the protective gas, and carry out a polymerization reaction. The pressure in the reaction kettle is 6 Pa relative to atmospheric pressure, the reaction temperature is 65 °C, the reaction duration is 7 h, and the stirring speed is 90 r / min. After the reaction is completed, an acrylic polymer is obtained.

[0046] S3-2. Raise the temperature of the reaction kettle to 88 °C, then add a modifier and an emulsifier to the reaction kettle. The addition amount of the modifier accounts for 6% of the total mass of the acrylic polymer, and the addition amount of the emulsifier accounts for 4% of the total mass of the acrylic polymer. Continue to stir for 4.5 h, evacuate the reaction kettle to 10 Pa, and keep it for 1.5 h to obtain a modified acrylic resin.

[0047] The emulsifier uses allyloxy nonylphenol polyoxyethylene ether bisphosphate, the crosslinking agent uses glycerol acrylate, the initiator uses azobisisobutyronitrile, and the modifier uses epoxy resin.

[0048] Example 3:

[0049] A preparation method of a high-temperature resistant water-based environmental protection glue includes the following steps:

[0050] S1-1. Prepare materials with the following components by mass percentage: 15% modified polyurethane prepolymer, 9.6% modified acrylic resin, 7% polyvinylidene chloride, 5% coupling agent, 5% polyvinyl alcohol, 12% heat-resistant monomer, 4% silica powder, 3% alumina powder, and the balance is deionized water; the average particle size of both the silica powder and the alumina powder is 20 μm; the heat-resistant monomer is prepared by mixing vinylpyrrolidone and methyl methacrylate in a mass ratio of 1:1; the coupling agent is prepared by mixing 3-aminopropyltriethoxysilane and γ-glycidyletheroxypropyltrimethoxysilane in a mass ratio of 1:1;

[0051] S1-2. Add the above-mentioned deionized water to the reaction kettle, heat it to 80 °C and keep it at a constant temperature, then add the modified polyurethane prepolymer, modified acrylic resin, and polyvinylidene chloride to the reaction kettle and mix and stir; the stirring speed is 120 r / min, the stirring duration is 6 h, and ultrasonic treatment is carried out during stirring. The ultrasonic frequency of the ultrasonic treatment is 40 Hz, and the ultrasonic wavelength is 0.5 mm; after the stirring is completed, add the heat-resistant monomer and polyvinyl alcohol by weight and continue to stir for 4 h to obtain a colloidal solution;

[0052] S1-3. Continue to add the coupling agent, silica powder, and alumina powder to the reaction kettle containing the colloidal solution, raise the temperature to 90 °C, and continuously stir for 3 h, then cool to room temperature of 30 °C, and carry out vacuum degassing treatment. The vacuum degassing treatment is to evacuate the reaction kettle to 8 Pa and keep it for 3 h; then carry out filling to obtain the water-based environmental protection glue.

[0053] The preparation method of the modified polyurethane prepolymer in step S1-1 includes the following steps:

[0054] S2-1. Drop the polyester polyol into the reaction kettle containing isocyanate, stir under the protection of a nitrogen atmosphere, the stirring speed is 100 r / min, the reaction temperature is 90 °C, and the reaction duration is 8 h to obtain a polyurethane prepolymer; the molar ratio of the polyester polyol to the isocyanate is 2:1;

[0055] S2-2. Lower the temperature of the reaction kettle to 50 °C, then continue to add the modifier to the reaction kettle. The addition amount of the modifier is 25% of the total mass of the polyurethane prepolymer, keep the stirring speed unchanged, and continuously stir for 6 h. After the stirring is completed, add a chain extender to the reaction kettle for chain extension reaction. The chain extender is diethylenetriamine, and the addition amount of the chain extender is 15% of the total mass of the polyurethane prepolymer. Keep the stirring speed unchanged and continuously stir for 5 h to obtain the modified polyurethane prepolymer.

[0056] The preparation method of the modifier is as follows: Mix γ-aminopropyltriethoxysilane and nano-SiO2 and put them into a reaction kettle. The dosage of γ-aminopropyltriethoxysilane is 5wt% of nano-SiO2. The temperature of the reaction kettle is 95 °C, the reaction duration is 8 h. After the reaction, the obtained product is washed to remove the unreacted γ-aminopropyltriethoxysilane, and then vacuum dried to obtain the modifier.

[0057] The preparation method of the modified acrylic resin includes the following steps:

[0058] S3-1. Add acrylate monomer, crosslinking agent, and initiator into the reaction kettle according to the mass ratio of 87:5:3. Use argon as the protective gas for polymerization reaction. The pressure in the reaction kettle is 10 Pa relative to atmospheric pressure, the temperature of the reaction kettle is 70 °C, the reaction duration is 10 h, and the stirring speed is 100 r / min. After the reaction is completed, acrylic polymer is obtained.

[0059] S3-2. Heat the reaction kettle to 90 °C, then add the modifier and emulsifier into the reaction kettle. The addition amount of the modifier accounts for 10% of the total mass of the acrylic polymer, and the addition amount of the emulsifier accounts for 7% of the total mass of the acrylic polymer. Continue stirring for 5 h, evacuate the reaction kettle to 15 Pa and keep it for 3 h to obtain the modified acrylic resin.

[0060] The emulsifier uses allyloxy nonylphenol polyoxyethylene ether bisphosphate, the crosslinking agent uses glycerol acrylate, the initiator uses azobisisobutyronitrile, and the modifier uses epoxy resin.

[0061] Comparing Example 1 - Example 3, Example 3 has the greatest viscosity and the best high-temperature resistance performance. Therefore, Example 3 is the best example.

[0062] Example 4:

[0063] Based on Example 3, the difference between Example 4 and Example 3 is that in S1-1, prepare materials according to the following mass percentage components: 15% modified polyurethane prepolymer, 9.6% modified acrylic resin, 7% polyvinylidene chloride, 5% coupling agent, 5% polyvinyl alcohol, 10% heat-resistant monomer, 4% silica powder, 3% alumina powder, and the balance is deionized water.

[0064] Comparing Example 3 - Example 4, in Example 4, due to the decrease in the content of the heat-resistant monomer, the high-temperature resistance performance of the prepared water-based environmental protection glue decreases.

[0065] Example 5:

[0066] Based on Example 3, the difference between Example 5 and Example 3 is that in Example 5, the vacuum degassing treatment is to evacuate the reaction kettle to 4 Pa and keep it for 3 h.

[0067] Comparing Example 3 - Example 5, the water - based environmental protection glue prepared in Example 5 has the least amount of internal bubbles. Therefore, the effect of Example 5 is better.

[0068] Example 6:

[0069] Based on Example 5, the difference between Example 6 and Example 5 is as follows: in S2 - 2, the temperature of the reaction kettle is reduced to 50 °C, and then a modifier is continuously added to the reaction kettle. The addition amount of the modifier is 23% of the total mass of the polyurethane prepolymer. The stirring speed remains unchanged, and continuous stirring is carried out for 6 h. After the stirring is completed, a chain extender is added to the reaction kettle for chain extension reaction. The chain extender used is diethylenetriamine, and the addition amount of the chain extender is 15% of the total mass of the polyurethane prepolymer. Keeping the stirring speed unchanged, after continuous stirring for 5 h, a modified polyurethane prepolymer is obtained.

[0070] Comparing Example 5 and Example 6, when preparing the modified polyurethane prepolymer in Example 6, the addition amount of the modifier is reduced. The heat - resistance performance and viscosity of the water - based environmental protection glue prepared in Example 6 have decreased.

[0071] Example 7:

[0072] Based on Example 5, the difference between Example 7 and Example 5 is as follows: in S2 - 2, the temperature of the reaction kettle is reduced to 50 °C, and then a modifier is continuously added to the reaction kettle. The addition amount of the modifier is 25% of the total mass of the polyurethane prepolymer. The stirring speed remains unchanged, and continuous stirring is carried out for 6 h. After the stirring is completed, a chain extender is added to the reaction kettle for chain extension reaction. The addition amount of the chain extender is 13% of the total mass of the polyurethane prepolymer. Keeping the stirring speed unchanged, after continuous stirring for 5 h, a modified polyurethane prepolymer is obtained.

[0073] Comparing Example 5 and Example 7, when preparing the modified polyurethane prepolymer in Example 7, the addition amount of the chain extender is reduced. Comparing the water - based environmental protection glues prepared in Example 5 and Example 7, it is found that the viscosity of the glue in Example 5 is better.

[0074] Example 8:

[0075] Based on Example 5, the difference between Example 8 and Example 13 is as follows: in S3 - 2, the temperature of the reaction kettle is raised to 90 °C, and then a modifier and an emulsifier are added to the reaction kettle. The addition amount of the modifier accounts for 8% of the total mass of the acrylic polymer, and the addition amount of the emulsifier accounts for 7% of the total mass of the acrylic polymer. Continue stirring for 5 h, evacuate the reaction kettle to 15 Pa, and keep it for 3 h to obtain a modified acrylic resin.

[0076] Comparing Example 5 and Example 8, when preparing with the modified acrylic resin in Example 8, the addition amount of the modifier is reduced. Comparing the water - based environmental protection glues prepared in Example 5 and Example 8, the viscosity of the water - based environmental protection glue prepared in Example 8 has decreased.

[0077] Example 9:

[0078] Based on Example 5, the difference between Example 9 and Example 5 is that in S3-2, the reaction kettle is heated to 90 °C, and then a modifier and an emulsifier are added to the reaction kettle. The addition amount of the modifier accounts for 10% of the total mass of the acrylic polymer, and the addition amount of the emulsifier accounts for 7% of the total mass of the acrylic polymer. Stir continuously for 5 h, evacuate the reaction kettle to 7 Pa, and keep it for 3 h to obtain the modified acrylic resin.

[0079] Comparing the water-based environmental protection adhesives prepared in Comparative Example 5 and Example 9, the water-based environmental protection adhesive prepared in Example 9 has the least bubble content. Therefore, Example 9 is the best example.

[0080] The viscosities and high-temperature resistance performances of the water-based environmental protection adhesives prepared in Examples 1-9 are compared in Table 1;

[0081] Table 1: Performance comparison of water-based environmental protection adhesives in Examples 1-9:

[0082]

[0083] Through the data comparison in Table 1, the water-based environmental protection adhesive prepared in Example 9 has the best viscosity and high-temperature resistance performance and the smallest bubble content. Therefore, the water-based environmental protection adhesive prepared in Example 9 has the best use effect.

Claims

1. A method for preparing a high temperature resistant water-based environmentally friendly adhesive, characterized in that: The following steps are involved: S1-1. Prepare the following ingredients in percentage by mass: 13-15% modified polyurethane prepolymer, 7.5-9.6% modified acrylic resin, 5-7% polyvinylidene chloride, 4-5% coupling agent, 3-5% polyvinyl alcohol, 7-12% heat-resistant monomer, 3-4% silicon dioxide powder, 1-3% aluminum oxide powder, and the balance is deionized water; S1-2, adding the above deionized water to a reactor, and heating to 70-80°C to maintain a constant temperature, then adding modified polyurethane prepolymer, modified acrylic resin, and polyvinylidene chloride to the reactor and mixing and stirring; stirring speed 120r / min, stirring time 4-6h, stirring accompanied by ultrasonic treatment, after stirring is completed, adding heat-resistant monomer and polyvinyl alcohol according to the weight parts and continuing stirring for 2-4h to obtain a colloidal solution; S1-3, continue to add coupling agent, silicon dioxide powder and aluminum oxide powder to the reaction kettle containing the colloidal solution, heat to 80-90°C, continue stirring for 2-3h, then cool to room temperature, perform vacuum degassing treatment, and then fill to obtain water-based environmentally friendly glue; The coupling agent is prepared by mixing 3-aminopropyltriethoxysilane and γ-glycidyloxypropyltrimethoxysilane in a mass ratio of 1:1; The method for preparing the modified polyurethane prepolymer in step S1-1 comprises the following steps: S2-1, adding polyester polyol dropwise to a reaction kettle containing isocyanate, stirring under nitrogen atmosphere protection, stirring at a speed of 80-100 r / min, a reaction temperature of 70-90° C., and a reaction time of 5-8 h to obtain a polyurethane prepolymer; the molar ratio of the polyester polyol to the isocyanate is 2:1; S2-2, lowering the temperature of the reactor to 40-50°C, and then continuing to add the modifier to the reactor, the amount of the modifier added is 20-25% of the total mass of the polyurethane prepolymer, the stirring speed remains unchanged, and the stirring is continued for 4-6 hours. After the stirring is completed, a chain extender is added to the reactor for chain extension reaction, and the amount of the chain extender added is 10-15% of the total mass of the polyurethane prepolymer. The stirring speed is kept unchanged, and the stirring is continued for 2-5 hours to obtain a modified polyurethane prepolymer; The preparation method of the modifier is as follows: γ-aminopropyltriethoxysilane and nano-SiO2 are mixed and put into a reaction kettle, wherein the amount of γ-aminopropyltriethoxysilane used is 1-5wt% of the nano-SiO2, the temperature of the reaction kettle is 80-95° C., the reaction time is 5-8h, the product obtained after the reaction is washed to remove the unreacted γ-aminopropyltriethoxysilane, and then vacuum dried to obtain the modifier; The preparation method of the modified acrylic resin comprises the following steps: S3-1, adding acrylate monomer, crosslinking agent and initiator into a reactor in a mass ratio of 87:5:3, using argon as a protective gas, to carry out polymerization reaction, the reactor pressure is 5-10Pa relative to the atmospheric pressure, the reactor temperature is 60-70°C, the reaction time is 5-10h, the stirring speed is 80-100r / min, and after the reaction is completed, an acrylic acid polymer is obtained; S3-2, heat the reactor to 80-90°C, then add a modifier and an emulsifier to the reactor, wherein the amount of the modifier added accounts for 5-10% of the total mass of the acrylic polymer, and the amount of the emulsifier added accounts for 3-7% of the total mass of the acrylic polymer. Continue stirring for 4-5 hours, evacuate the reactor to 7-15Pa, and maintain for 2-3 hours to obtain a modified acrylic resin.

2. The method for preparing a high temperature resistant water-based environmentally friendly adhesive according to claim 1, characterized in that: The emulsifier is allyloxy nonylphenol polyoxyethylene ether diphosphoric acid, the crosslinking agent is glycerol acrylate, the initiator is azobisisobutyronitrile, and the modifier is epoxy resin.

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