A high-barrier aluminized paper and a preparation method thereof

Abstract

The application discloses high-barrier aluminized paper and a preparation method thereof, and relates to the field of paper packaging materials. The high-barrier aluminized paper comprises a direct-plating base paper, a primer layer, an aluminized layer and a top coating layer arranged in sequence. The primer layer is prepared by using modified polyvinyl alcohol water-based paint, the modified polyvinyl alcohol water-based paint is prepared from 7-10 wt% polyvinyl alcohol, 2-4 wt% water-based polyurethane, 1-3 wt% nano filler, 30-40 wt% isopropyl alcohol and the rest water, the top coating layer is prepared by using water-based heat-sealing paint, and the water-based heat-sealing paint is prepared from 15-35 wt% ethylene-acrylic acid copolymer, 10-20 wt% hot-melt polyurethane, 1-2 wt% anti-sticking agent and the rest water-based dispersant. The high-barrier aluminized paper has a simpler structure, a simpler preparation process, excellent water-oxygen barrier property and biodegradability, and high heat-sealing strength.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of paper packaging materials, in particular to a high-barrier aluminized paper and a preparation method thereof. BACKGROUND

[0002] Although plastic packaging has the advantages of excellent barrier property and low cost, plastic packaging is usually a one-time use material, and most plastics are non-degradable packaging materials, which seriously pollute the environment. At present, with the continuous improvement of environmental protection requirements, the use of plastic packaging is increasingly restricted.

[0003] Paper packaging materials have very good prospects as environmentally friendly packaging materials due to their good biodegradability and easy processing characteristics. However, due to the fiber exposure and microporosity of paper itself, paper has high hydrophilicity and hygroscopicity, i.e., the water and oxygen barrier properties of traditional paper packaging materials are poor.

[0004] To improve the water and oxygen barrier properties of traditional paper packaging, patent CN118407281A discloses a preparation method of a double-sided aluminized paper. The aluminized paper needs to be evaporated and plated on both sides multiple times and coated multiple times to achieve a certain water and oxygen barrier property, which has the problems of complex product structure and complicated process.

[0005] Therefore, how to improve the water and oxygen barrier properties of paper packaging materials while preventing the problem of complicated process is the research focus of paper packaging materials at present. SUMMARY

[0006] To improve the water and oxygen barrier properties and durability of paper packaging materials while preventing the problem of complicated process, the present application provides a high-barrier aluminized paper and a preparation method thereof.

[0007] In a first aspect, the present application provides a high-barrier aluminized paper using the following technical solution:

[0008] A high-barrier aluminized paper, comprising a direct plating base paper, a bottom coating layer, an aluminized layer and a surface coating layer arranged in sequence.

[0009] The bottom coating layer is made of a modified polyvinyl alcohol water-based paint, and the modified polyvinyl alcohol water-based paint is made of 7-10 wt% polyvinyl alcohol, 2-4 wt% water-based polyurethane, 1-3 wt% nano filler, 30-40 wt% isopropyl alcohol and the balance of water.

[0010] The surface coating layer is made of a water-based heat-seal coating, and the water-based heat-seal coating is made of 15-35 wt% ethylene-acrylic acid copolymer, 10-20 wt% hot melt polyurethane, 1-2 wt% anti-sticking agent and the balance of water-based dispersant.

[0011] The high-barrier aluminized paper of the present application is a four-layer structure, which is a direct aluminizing base paper, a primer layer, an aluminized layer and a topcoat layer. Compared with the existing double-sided aluminized paper, the high-barrier aluminized paper of the present application has a simpler structure and a more convenient preparation process.

[0012] The primer layer is prepared by using a modified polyvinyl alcohol water-based paint prepared by polyvinyl alcohol, water-based polyurethane and nano filler. The primer layer formed by polyvinyl alcohol, water-based polyurethane and nano filler can fill the micropores on the direct aluminizing base paper to improve the water and oxygen barrier performance of the aluminized paper, and can provide a basis for the stable adhesion of the aluminized layer. On the other hand, the specific ratio of polyvinyl alcohol and water-based polyurethane can make the primer layer have good biodegradability, bending resistance and solvent resistance.

[0013] The aluminized layer is located between the primer layer and the topcoat layer. The dense aluminized layer can further improve the water and oxygen barrier performance of the aluminized paper, and the topcoat layer can provide protection for the aluminized paper.

[0014] The topcoat layer is prepared by using a water-based heat-sealable paint prepared by water-based polyurethane and anti-adhesive agent. The use of water-based polyurethane as the topcoat layer has environmental protection, bending resistance and heat-sealability. The addition of anti-adhesive agent can prevent the problem of adhesion of the topcoat layer during winding of the high-barrier aluminized paper.

[0015] Preferably, the water-based polyurethane is prepared by glycerol polyoxyethylene polyoxypropylene ether, polyoxypropylene triamine, 2,2-dimethylol butyric acid, isocyanate-terminated prepolymer, neutralizing agent, catalyst, acetone and water in a weight ratio of (5-8):(2.5-3.5):(8-10):(55-65):(1-1.5):(0.01-0.02):(25-35):150. The isocyanate-terminated prepolymer is prepared by polytetrahydrofuran ether diol, polycaprolactone diol and isocyanate in a molar ratio of (0.1-0.2):(0.3-0.4):1.

[0016] In the present application, the water-based polyurethane is preferably a water-based polyurethane prepared by glycerol polyoxyethylene polyoxypropylene ether, polyoxypropylene triamine, 2,2-dimethylol butyric acid, isocyanate-terminated prepolymer, neutralizing agent, etc. in the above-mentioned ratio. This water-based polyurethane is not only conducive to uniform coating of the primer layer and the topcoat layer, but also has excellent bending resistance and solvent resistance, which can effectively improve the performance of the aluminized paper. At the same time, when used as the topcoat layer of the aluminized paper, the water-based polyurethane can achieve a heat-seal strength of 3.0N / 15cm at 120-125℃.

[0017] In some specific embodiments, the molecular weight of the glycerol polyoxyethylene polyoxypropylene ether ranges from 2500 to 3500, the molecular weight of the polypropylene oxide triamine ranges from 2500 to 3500, the molecular weight of the polytetrahydrofuran ether diol ranges from 1500 to 2500, and the molecular weight of the polycaprolactone diol ranges from 1500 to 2500.

[0018] In some specific embodiments, the neutralizing agent is dimethyl ethanol amine.

[0019] Compared with triethylamine as the neutralizing agent, the use of dimethyl ethanol amine as the neutralizing agent is conducive to improving the stability of the waterborne polyurethane system and further improving the solvent resistance of the waterborne polyurethane.

[0020] In some specific embodiments, the method for preparing the waterborne polyurethane comprises the following steps:

[0021] After vacuum dehydration of the polytetrahydrofuran ether diol and the polycaprolactone diol, the temperature is lowered to 40-50℃, and isocyanate is added under nitrogen protection, the reaction temperature is controlled at 80-100℃, and the reaction is carried out for 1.5-2.5h, and then vacuum degassing is performed to obtain an isocyanate-terminated prepolymer;

[0022] The polypropylene oxide triamine is added to the isocyanate-terminated prepolymer, the temperature is controlled at 10-20℃, and the reaction is carried out for 1-2h, then the glycerol polyoxyethylene polyoxypropylene ether, 2,2-dimethylol butyric acid and a catalyst are added, the temperature is raised to 75-80℃, and the reaction is carried out for 1-2h, then the temperature is lowered to 40-50℃, the neutralizing agent is added, and after uniform stirring, acetone and water are added, shear emulsification is carried out, and finally acetone is removed by vacuum distillation to obtain the waterborne polyurethane.

[0023] In the preparation of the waterborne polyurethane, the above method is used, which is conducive to improving the safety in the production process, and the waterborne polyurethane prepared by the above method is not only conducive to realizing uniform coating of the base coating and the top coating, but also has excellent bending resistance and solvent resistance, which can effectively improve the performance of the aluminum-plated paper, and when the waterborne polyurethane is used as the top coating of the aluminum-plated paper, a heat sealing strength of 3.0N / 15cm can be achieved at 120-125℃.

[0024] In some specific embodiments, the nano filler is at least one of nano titanium dioxide, nano mica sheet and nano silicon dioxide.

[0025] In some specific embodiments, the grammage of the direct plating base paper ranges from 45 to 95g / m 2 .

[0026] In some specific embodiments, the anti-sticking agent is a water-based wax emulsion.

[0027] The anti-sticking agent is a water-based wax emulsion, which is beneficial to the uniform dispersion of the anti-sticking agent and the water-based polyurethane, and does not cause adverse effects on the uniform coating of the top coating.

[0028] In a second aspect, the application provides a preparation method of the high-barrier aluminized paper.

[0029] The preparation method of the high-barrier aluminized paper comprises the following steps:

[0030] S1, coating a modified polyvinyl alcohol water-based paint on one surface of the direct aluminizing base paper, and drying to obtain a bottom coating;

[0031] S2, vacuum aluminizing the bottom coating away from the direct aluminizing base paper to obtain an aluminized layer;

[0032] S3, coating a water-based heat-sealing material on the side of the aluminized layer away from the bottom coating, and drying to obtain a top coating.

[0033] The application only needs to complete the preparation of the aluminized paper through two coating and one evaporation, which simplifies the process and realizes the high water-oxygen barrier performance and environmental protection performance of the aluminized paper.

[0034] In some specific embodiments, the dry coating amount of the modified polyvinyl alcohol water-based paint is 3-5 g / m 2 , and the coating speed is 80-120 m / min; the dry coating amount of the water-based heat-sealing material is 4-7 g / m 2 , and the coating speed is 80-120 m / min.

[0035] In some specific embodiments, in S2, the aluminizing speed is 4-7 m / s, the vacuum degree is less than 5.0E-4 mBar, and the thickness of the aluminized layer is 70-100 nm.

[0036] In some specific embodiments, the method further comprises the following steps:

[0037] S4, humidifying the side of the direct aluminizing base paper away from the bottom coating, the humidification pressure is 0.2-0.3 bar, the humidification amount is 5-50 kg / h, and the humidification time is 5-30 s.

[0038] In the application, the humidification treatment of the direct aluminizing base paper can improve the stress curling of the aluminized paper caused by the internal humidity imbalance, and compared with the existing stress curling elimination by coating on the side of the direct aluminizing base paper away from the bottom coating, the cost of the humidification treatment is lower.

[0039] In summary, the application at least includes the following beneficial technical effects:

[0040] (1) The high-barrier aluminized paper of the present application is a four-layer structure, which is a direct plating base paper, a primer layer, an aluminized layer and a top coating layer. Compared with the existing double-sided aluminized paper, the structure of the high-barrier aluminized paper of the present application is simpler, and the preparation process is also simpler.

[0041] (2) The primer layer is prepared by using a modified polyvinyl alcohol water-based paint prepared by polyvinyl alcohol, water-based polyurethane and nano filler. The primer layer formed by polyvinyl alcohol, water-based polyurethane and nano filler can fill the micropores on the direct plating base paper to improve the barrier property of the aluminized paper to water and oxygen, and can provide a basis for the stable adhesion of the aluminized layer. On the other hand, polyvinyl alcohol and water-based polyurethane can be compounded in a specific ratio to make the primer layer have good biodegradability, bending resistance and solvent resistance.

[0042] (3) The top coating layer is prepared by using a water-based heat-sealable paint prepared by water-based polyurethane and anti-adhesive agent. The water-based polyurethane as the top coating layer has environmental protection, bending resistance and heat-sealing property. The addition of the anti-adhesive agent can prevent the problem of adhesion of the top coating layer when the high-barrier aluminized paper is wound. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 is a structural schematic diagram of a high-barrier aluminized paper of the present application.

[0044] BRIEF DESCRIPTION OF DRAWINGS

[0045] 1. Direct plating base paper; 2. Primer layer; 3. Aluminized layer; 4. Top coating layer. DETAILED DESCRIPTION

[0046] The present application will be further described below in combination with specific experiments.

[0047] Preparation Example

[0048] Preparation Example 1

[0049] A water-based polyurethane is prepared by using glycerol polyoxyethylene polyoxypropylene ether (Haisi flower, molecular weight 3000), polyoxypropylene triamine (Jeffamine T-3000), 2,2-dimethylol butyric acid, isocyanate-terminated prepolymer, dimethyl ethanolamine, dibutyl tin dilaurate, acetone and water in a weight ratio of 5:2.5:10:65:1.5:0.01:25:150. The isocyanate-terminated prepolymer is prepared by 1 mol of polytetrahydrofuran ether diol (BASF PolyTHF2000), 4 mol of polycaprolactone diol (BASF PD1-20) and 10 mol of isophorone diisocyanate.

[0050] In the present preparation example, the preparation method of the water-based polyurethane includes the following steps:

[0051] Polytetrahydrofuran ether diol, polycaprolactone diol were vacuum dehydrated and cooled to 40℃, then isophorone diisocyanate was added under nitrogen protection, the reaction temperature was controlled at 80℃ for 2.5h, vacuum degassing was performed, and an isocyanate-terminated prepolymer was obtained; polyoxypropylene triamine was added to the isocyanate-terminated prepolymer according to the ratio, and the temperature was controlled at 10℃ for 2h, then glycerol polyoxyethylene polyoxypropylene ether, 2,2-dimethylol butyric acid and dibutyl tin dilaurate were added, the temperature was raised to 75℃ for 2h, then the temperature was lowered to 40℃, dimethyl ethanolamine was added, stirring was performed until uniform, then acetone and water were added, shear emulsification was performed, and finally acetone was removed by vacuum distillation to obtain the aqueous polyurethane.

[0052]

Preparation Example 2

[0053] An aqueous polyurethane was prepared from glycerol polyoxyethylene polyoxypropylene ether (Hishika, molecular weight 3000), polyoxypropylene triamine (Jeffamine T-3000), 2,2-dimethylol butyric acid, isocyanate-terminated prepolymer, dimethyl ethanolamine, dibutyl tin dilaurate, acetone and water according to the weight ratio of 8:3.5:8:55:1:0.02:35:150, wherein the isocyanate-terminated prepolymer was prepared from 3 mol of polytetrahydrofuran ether diol (BASF PolyTHF2000), 3 mol of polycaprolactone diol (BASF PD1-20) and 10 mol of isophorone diisocyanate.

[0054] In the present preparation example, the method for preparing the aqueous polyurethane comprises the following steps:

[0055] Polytetrahydrofuran ether diol, polycaprolactone diol were vacuum dehydrated and cooled to 50℃, then isophorone diisocyanate was added under nitrogen protection, the reaction temperature was controlled at 100℃ for 1.5h, vacuum degassing was performed, and an isocyanate-terminated prepolymer was obtained; polyoxypropylene triamine was added to the isocyanate-terminated prepolymer according to the ratio, and the temperature was controlled at 20℃ for 1h, then glycerol polyoxyethylene polyoxypropylene ether, 2,2-dimethylol butyric acid and dibutyl tin dilaurate were added, the temperature was raised to 80℃ for 1h, then the temperature was lowered to 50℃, dimethyl ethanolamine was added, stirring was performed until uniform, then acetone and water were added, shear emulsification was performed, and finally acetone was removed by vacuum distillation to obtain the aqueous polyurethane.

[0056]

Preparation Example 3

[0057] An aqueous polyurethane, which is different from that of

Preparation Example 1

[0058] The weight ratio of glycerol polyoxyethylene polyoxypropylene ether, polypropylene oxide triamine, 2,2-dimethylol butyric acid, isocyanate-terminated prepolymer, dimethyl ethanolamine, dibutyl tin dilaurate, acetone and water in the aqueous polyurethane of the present preparation example is 3:9:8:65:1.5:0.01:25:150.

[0059] Preparation Example 4

[0060] An aqueous polyurethane, which is different from the preparation example 1 in that the glycerol polyoxyethylene polyoxypropylene ether is replaced by equal mass of polypropylene oxide triamine.

[0061] Preparation Example 5

[0062] An aqueous polyurethane, which is different from the preparation example 1 in that the polypropylene oxide triamine is replaced by equal mass of glycerol polyoxyethylene polyoxypropylene ether.

[0063] Example

[0064] Example 1

[0065] A high-barrier aluminized paper, which comprises a direct aluminized base paper, a primer layer, an aluminized layer and a topcoat layer arranged in sequence, wherein the primer layer is prepared from a modified polyvinyl alcohol aqueous coating, and the modified polyvinyl alcohol aqueous coating is prepared by uniformly mixing 7wt% of polyvinyl alcohol (polyvinyl alcohol 2488), 4wt% of the aqueous polyurethane prepared in the preparation example 1, 3wt% of nano-silica and 40wt% of isopropyl alcohol, and the balance of water. 2 The topcoat layer is prepared from an aqueous heat-seal coating, and the aqueous heat-seal coating is prepared by uniformly mixing 35wt% of the aqueous polyurethane prepared in the preparation example 1, 1wt% of an aqueous wax emulsion (Mikado ME92040) and the balance of water.

[0066] In the present example, the preparation method of the high-barrier aluminized paper comprises the following steps:

[0067] S1, applying the modified polyvinyl alcohol aqueous coating on one surface of the direct aluminized base paper, the dry coating amount of the modified polyvinyl alcohol aqueous coating being 3g / m 2 , the coating speed being 120m / min, and the primer layer being obtained after drying;

[0068] S2, vacuum aluminizing the primer layer away from the direct aluminized base paper to obtain the aluminized layer, the aluminizing speed being 6m / s, the vacuum degree being less than 5.0E-4mBar, and the thickness of the aluminized layer being 70nm;

[0069] S3, applying the aqueous heat-seal material on the side of the aluminized layer away from the primer layer, the dry coating amount of the aqueous heat-seal material being 4g / m 2 , the coating speed being 120m / min, and the topcoat layer being obtained after drying;

[0070] S4, the side of the direct plating base paper away from the primer layer is subjected to a humidification treatment, the humidifier pressure is 0.25 bar, the humidification amount is 10 kg / h, the particle size of the water mist is 10-30 μm, and the humidification treatment time is 30 s.

[0071] Example 2

[0072] A high-barrier aluminum-plated paper, which differs from Example 1 in that the raw material composition of the primer layer and the topcoat layer is different.

[0073] The primer layer is prepared from a modified polyvinyl alcohol water-based paint, which is prepared by uniformly mixing 10 wt% polyvinyl alcohol (polyvinyl alcohol 2488), 2 wt% water-based polyurethane prepared in Preparation Example 2, 1 wt% nanometer mica flake, 30 wt% isopropyl alcohol, and the balance of water. The topcoat layer is prepared from a water-based heat-seal paint, which is prepared by uniformly mixing 45 wt% water-based polyurethane prepared in Preparation Example 2, 2 wt% water-based wax emulsion (Makoto ME92040), and the balance of water.

[0074] Example 3

[0075] A high-barrier aluminum-plated paper, which differs from Example 1 in that the water-based polyurethane in the modified polyvinyl alcohol water-based paint and the water-based heat-seal paint is replaced by water-based polyurethane prepared in Preparation Example 3.

[0076] Example 4

[0077] A high-barrier aluminum-plated paper, which differs from Example 1 in that the water-based polyurethane in the modified polyvinyl alcohol water-based paint and the water-based heat-seal paint is replaced by water-based polyurethane prepared in Preparation Example 4.

[0078] Example 5

[0079] A high-barrier aluminum-plated paper, which differs from Example 1 in that the water-based polyurethane in the modified polyvinyl alcohol water-based paint and the water-based heat-seal paint is replaced by water-based polyurethane prepared in Preparation Example 5.

[0080] Comparative Example

[0081] Comparative Example 1

[0082] An aluminum-plated paper, which differs from Example 1 in that the modified polyvinyl alcohol water-based paint used in the primer layer does not contain water-based polyurethane prepared in Preparation Example 1.

[0083] Comparative Example 2

[0084] An aluminum-plated paper, which differs from Example 1 in that the paint used in the primer layer does not contain polyvinyl alcohol.

[0085] Performance test

[0086] 1. Oxygen transmission rate: Test the oxygen transmission rate of the aluminized paper in each example and the comparative example according to ASTM D 3985, wherein the smaller the oxygen transmission rate, the better the oxygen barrier performance.

[0087] 2. Water vapor transmission rate: Test the water vapor transmission rate of the aluminized paper in each example and the comparative example according to ASTM F 1249, wherein the smaller the water vapor transmission rate, the better the water vapor barrier performance.

[0088] 3. Heat seal strength: Fold the aluminized paper in half, and heat seal the topcoat layer at 0.4 MPa and 125℃ for 0.5 s, and then test the ability of the aluminized paper at the sealing position to resist external force peeling.

[0089] 4. Bending cycle resistance: Cut the aluminized paper into 15 mm x 100 mm, and test it using a PY-D608D flexible material folding life tester, with the parameters set as a bending radius of 3 mm, a frequency of 0.5 Hz, and a bending angle of 90°, and record the number of times of life.

[0090] 5. Solvent resistance: Soak the aluminized paper in each example and the comparative example in water and ethanol for 3 d and 7 d, respectively, and then take it out, and observe whether there is a problem of bubbling or cracking, and if not, it is considered to pass the test.

[0091] Table 1

[0092]

[0093] Table 2

[0094]

[0095]

[0096] It can be known from the content described in Example 1 and Comparative Example 1 of the present application and Tables 1-2 that when the primer layer does not contain waterborne polyurethane, the bending resistance and solvent resistance of the aluminized paper are greatly reduced, which is not conducive to improving the durability of the aluminized paper.

[0097] It can be known from the content described in Example 1 and Comparative Example 2 of the present application and Tables 1-2 that when the primer layer does not contain polyvinyl alcohol, the water and oxygen barrier performance of the aluminized paper is greatly reduced, which is not conducive to prolonging the shelf life of the packaged goods.

[0098] It can be known from the content described in Embodiment 1 and Embodiment 3 and Tables 1-2 of the present application that when the weight ratio of glycerol polyoxyethylene polyoxypropylene ether, polyoxypropylene triamine, 2,2-dimethylol butyric acid and isocyanate-terminated prepolymer in the water-based polyurethane used in the base coating layer and the surface coating layer is not within the range of (5-8):(2.5-3.5):(8-10):(55-65) preferred by the present application, the barrier properties of the aluminum-plated paper to water vapor and oxygen decrease, and at the same time, the heat sealing strength and the bending resistance of the aluminum-plated paper also decrease.

[0099] It can be known from the content described in Embodiment 1 and Embodiment 4-5 and Tables 1-2 of the present application that when the glycerol polyoxyethylene polyoxypropylene ether in the water-based polyurethane used in the base coating layer and the surface coating layer is replaced by an equal amount of polyoxypropylene triamine, the barrier properties of the aluminum-plated paper to water vapor and oxygen decrease, and at the same time, the heat sealing strength and the bending resistance of the aluminum-plated paper also decrease.

[0100] It can be known from the content described in Embodiment 1 and Embodiment 5 and Tables 1-2 of the present application that when the polyoxypropylene triamine in the water-based polyurethane used in the base coating layer and the surface coating layer is replaced by an equal amount of glycerol polyoxyethylene polyoxypropylene ether, the barrier properties of the aluminum-plated paper to water vapor and oxygen decrease, and at the same time, the heat sealing strength of the aluminum-plated paper also decreases.

[0101] The specific embodiment is only an explanation of the present application, and is not a limitation of the present application. Those skilled in the art can make modifications to the specific embodiment without creative contribution after reading the present specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the Patent Law.

Claims

1. A high barrier aluminized paper, characterized by: The paper comprises a straight plating base paper, a primer layer, an aluminum plating layer and a top coating layer arranged in sequence; the primer layer is prepared by using a modified polyvinyl alcohol water-based paint, the modified polyvinyl alcohol water-based paint is prepared from 7-10 wt% polyvinyl alcohol, 2-4 wt% water-based polyurethane, 1-3 wt% nano filler, 30-40 wt% isopropyl alcohol and the rest water; the top coating layer is prepared by using a water-based heat sealing paint, the water-based heat sealing paint is prepared from 35-45 wt% water-based polyurethane, 1-2 wt% anti-sticking agent and the rest water-based dispersant; The water-based polyurethane is prepared from glycerol polyoxyethylene polyoxypropylene ether, polyoxypropylene triamine, 2,2-dimethylol butyric acid, isocyanate-terminated prepolymer, neutralizing agent, catalyst, acetone and water in a weight ratio of (5-8):(2.5-3.5):(8-10):(55-65):(1-1.5):(0.01-0.02):(25-35):150, wherein the isocyanate-terminated prepolymer is prepared from polytetrahydrofuran ether diol, polycaprolactone diol and isocyanate in a molar ratio of (0.1-0.2):(0.3-0.4):

1.

2. The high barrier aluminized paper according to claim 1, characterized in that: The molecular weight of the glycerol polyoxyethylene polyoxypropylene ether ranges from 2500 to 3500, the molecular weight of the polyoxypropylene triamine ranges from 2500 to 3500, the molecular weight of the polytetrahydrofuran ether diol ranges from 1500 to 2500, and the molecular weight of the polycaprolactone diol ranges from 1500 to 2500.

3. The high barrier aluminized paper according to claim 1, characterized in that: The neutralizing agent is dimethyl ethanolamine.

4. A high barrier aluminized paper according to any one of claims 1 to 3, characterized in that: The preparation method of the water-based polyurethane comprises the following steps: vacuum dehydration of polytetrahydrofuran ether diol and polycaprolactone diol, cooling to 40-50℃, adding isocyanate under nitrogen protection, controlling the reaction temperature to be 80-100℃, reacting for 1.5-2.5h, vacuum degassing to obtain isocyanate-terminated prepolymer; adding polyoxypropylene triamine to the isocyanate-terminated prepolymer, controlling the temperature to be 10-20℃, reacting for 1-2h, then adding glycerol polyoxyethylene polyoxypropylene ether, 2,2-dimethylol butyric acid and catalyst, heating to 75-80℃, reacting for 1-2h, then cooling to 40-50℃, adding neutralizing agent, stirring uniformly, adding acetone and water, shearing, and finally removing acetone by reduced pressure distillation to obtain the water-based polyurethane.

5. A high barrier aluminized paper according to any one of claims 1 to 3, characterized in that: The anti-sticking agent is water-based wax emulsion.

6. A process for the preparation of a high barrier aluminized paper according to any one of claims 1 to 5, characterized in that, The method comprises the following steps: S1, coating modified polyvinyl alcohol water-based paint on one surface of the straight plating base paper, and drying to obtain a primer layer; S2, vacuum aluminum plating on the primer layer away from the straight plating base paper to obtain an aluminum plating layer; S3, coating water-based heat sealing material on the side of the aluminum plating layer away from the primer layer, and drying to obtain a top coating layer.

7. The method of claim 6, wherein the method further comprises: The dry coating amount of the modified polyvinyl alcohol water-based paint is 3-5 g / m 2 , and the coating speed is 80-120 m / min; the dry coating amount of the water-based heat-sealing material is 4-7 g / m 2 , and the coating speed is 80-120 m / min.

8. The method of claim 6, wherein the method further comprises: In S2, the aluminum plating speed is 4-7m / s, the vacuum degree is less than 5.0E-4mBar, and the thickness of the aluminum plating layer is 70-100nm.

9. The method for preparing a high-barrier metallized paper according to claim 6, characterized in that, The method further comprises the following steps: S4, humidifying treatment is performed on the side of the straight plating base paper away from the primer layer, the humidifying pressure is 0.2-0.3bar, the humidifying amount is 5-50kg / h, and the humidifying time is 5-30s.

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