High-molecular-weight polyvinyl ether A50 resin as well as preparation method and application thereof

Abstract

The invention provides high-molecular-weight polyvinyl ether A50 resin and a preparation method and application thereof, and belongs to the technical field of high polymer materials, the preparation method comprises the following steps: mixing low-molecular-weight polyvinyl ether with an initiator, then adding vinyl ether for the first time to carry out a prepolymerization reaction, then adding vinyl ether for the second time to carry out a prepolymerization reaction, and finally adding vinyl ether for the second time to carry out a polymerization reaction to obtain the high-molecular-weight polyvinyl ether A50 resin. And reacting to obtain the high-molecular-weight polyvinyl ether A50 resin. The mass of the vinyl ethyl ether added for the first time accounts for 1-10% of the total mass of the vinyl ethyl ether added for the two times. The preparation method provided by the invention comprises the following steps: on the basis of low-molecular-weight polyvinyl ether, firstly adding part of vinyl ether monomer for prepolymerization reaction, and then adding vinyl ether again for continuous reaction to obtain high-molecular-weight polyvinyl ether A50 resin; according to the invention, bulk polymerization is adopted, no solvent is used, the process is environment-friendly, the operation is simple, and the prepared product has excellent performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer materials, and relates to a high molecular weight polyvinyl ethyl ether A50 resin, a preparation method thereof, and an application thereof. Background Art

[0002] Polyvinyl ethyl ether A50 resin is a yellow transparent viscous liquid, generally an amorphous homopolymer formed by vinyl ethyl ether monomers under the action of a cationic initiator or a free radical initiator. Polyvinyl ethyl ether A50 resin has a chain-like high molecular structure, in which ethoxy groups exist as branches of the high molecular chain, enhancing the flexibility of the polymer; the presence of a large number of ether bonds in the high molecular chain enables the polymer coating film to have good adhesion to the substrate. Polyvinyl ethyl ether A50 resin does not contain reactive double bonds, so it is not easily oxidized and degraded by the atmosphere, and the prepared coating has good aging resistance. It has good miscibility with other polymer materials and can be used for modifying other materials. Due to its special properties, it is widely used in fields such as ship coatings, automotive coatings, and high-end inks. Its average molecular weight is generally characterized by the K value, and the higher the K value, the larger the molecular weight.

[0003] In the prior art, its preparation method is usually to add a solvent and a catalyst to a reaction kettle, and then continuously dropwise add vinyl ethyl ether, and carry out a polymerization reaction under the action of the catalyst, and obtain the target polymer after removing the solvent. However, the polymer obtained by the above method has a low molecular weight (M n < 1000), and the product viscosity is low (< 1000 mPa·s), and it is mainly applied to the field of refrigeration lubricating oil, and cannot meet the application requirements in the coating field.

[0004] Therefore, in this field, it is desired to develop a preparation method of high molecular weight polyvinyl ethyl ether A50 resin, which is simple in operation and has excellent product performance. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a high molecular weight polyvinyl ethyl ether A50 resin, a preparation method thereof, and an application thereof.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] In the first aspect, the present invention provides a preparation method of a high molecular weight polyvinyl ethyl ether A50 resin, and the preparation method includes the following steps:

[0008] Mix low molecular weight polyvinyl ethyl ether and an initiator, then add vinyl ethyl ether for the first time, carry out a prepolymerization reaction, and then add vinyl ethyl ether for the second time and react to obtain the high molecular weight polyvinyl ethyl ether A50 resin;

[0009] The mass of the vinyl ethyl ether added for the first time accounts for 1% - 10% of the total mass of the vinyl ethyl ether added twice, such as 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., and the specific point values between the above point values. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the above range.

[0010] The preparation method provided by the present invention is based on low molecular weight polyvinyl ethyl ether. First, a part of vinyl ethyl ether monomer is added for prepolymerization reaction, and then vinyl ethyl ether is added again to continue the reaction, obtaining high molecular weight polyvinyl ethyl ether A50 resin. The present invention adopts bulk polymerization without using solvents, with environmental protection, simple operation, and the prepared product has stable quality and excellent performance.

[0011] By limiting the mass of the vinyl ethyl ether added for the first time to account for 1% - 10% of the total mass of the vinyl ethyl ether added twice, the present invention makes the polymerization process react gently and prevents explosive polymerization during the dropping process.

[0012] In the present invention, the "high molecular weight" in the high molecular weight polyvinyl ethyl ether A50 resin means that the K value of the polyvinyl ethyl ether A50 resin is 55 - 65.

[0013] Preferably, the K value of the low molecular weight polyvinyl ethyl ether < 20, such as 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 8, 6, 5, etc., and the specific point values between the above point values. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the above range.

[0014] Preferably, the addition amount of the low molecular weight polyvinyl ethyl ether accounts for 1% - 10% of the total weight of the preparation raw materials (i.e., the total of low molecular weight polyvinyl ethyl ether, initiator, vinyl ethyl ether added for the first time, and vinyl ethyl ether added for the second time), such as 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., and the specific point values between the above point values. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the above range.

[0015] Preferably, the initiator includes any one or a combination of at least two of Bronsted acid, Lewis acid, and organometallic compounds.

[0016] Preferably, the initiator includes boron trifluoride.

[0017] Preferably, the initiator is added in the form of an initiator solution.

[0018] Preferably, the solvent in the initiator solution includes any one or a combination of at least two of alcohol, phenol, ether, and acetal.

[0019] Preferably, the mass percentage of the initiator solution is 10% - 50%, such as 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc., as well as the specific point values between the above point values. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the range.

[0020] Preferably, the mass ratio of the total mass of vinyl ethyl ether added in the first and second times to the mass of the initiator is (5000 - 13000):1. 5000 - 13000 can be, for example, 5000, 5500, 6000, 6500, 7000, 7500, 8000, 8500, 9000, 9500, 10000, 10500, 11000, 11500, 12000, 12500, 13000, etc., as well as the specific point values between the above point values. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the range. By controlling the addition amount of the initiator, the purpose of controlling the K value of the polymer is achieved.

[0021] Preferably, the purity of the vinyl ethyl ether > 99%, such as 99.1%, 99.3%, 99.5%, 99.7%, 99.8%, 99.9%, etc., as well as the specific point values between the above point values. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the range.

[0022] Preferably, the temperature of the prepolymerization reaction is 0 - 30°C, such as 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, etc., as well as the specific point values between the above point values. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the range.

[0023] Preferably, the time of the prepolymerization reaction is 15 - 60 min, such as 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, etc., as well as the specific point values between the above point values. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the range.

[0024] Preferably, when adding vinyl ethyl ether for the second time, the system temperature is controlled at 0 - 30°C, such as 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, etc., as well as the specific point values between the above point values. Due to space limitations and for the sake of simplicity, the present invention does not exhaustively list the specific point values included in the range.

[0025] Preferably, the way of adding vinyl ethyl ether for the second time is dropwise addition.

[0026] Preferably, the second addition of vinyl ethyl ether specifically includes: adding vinyl ethyl ether for the second time in a dropping manner, and controlling the dropping time to be 5 to 10 hours, such as 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, etc., and specific point values between the above point values. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the above range.

[0027] Preferably, the reaction time is 8 to 12 hours, such as 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, etc., and specific point values between the above point values. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the above range.

[0028] Preferably, the second addition of vinyl ethyl ether and the reaction specifically include: adding vinyl ethyl ether for the second time in a dropping manner, and controlling the dropping time to be 5 to 10 hours, such as 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, etc., and specific point values between the above point values. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the above range. After the dropping is completed, continue the reaction for 1 to 3 hours, such as 1 hour, 2 hours, 3 hours, etc., and specific point values between the above point values. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the above range.

[0029] As a preferred technical solution of the present invention, the preparation method includes the following steps:

[0030] Mix low molecular weight polyvinyl ethyl ether and an initiator, then add vinyl ethyl ether for the first time, carry out a prepolymerization reaction at 0 to 30 °C for 15 to 60 min, control the system temperature to be 0 to 30 °C, then add vinyl ethyl ether for the second time in a dropping manner, and control the dropping time to be 5 to 10 hours. After the dropping is completed, continue the reaction for 1 to 3 hours to obtain the high molecular weight polyvinyl ethyl ether A50 resin.

[0031] In a second aspect, the present invention provides a high molecular weight polyvinyl ethyl ether A50 resin, and the high molecular weight polyvinyl ethyl ether A50 resin is prepared by the preparation method described in the first aspect.

[0032] In a third aspect, the present invention provides a high molecular weight polyvinyl ethyl ether A50 resin solution, and the high molecular weight polyvinyl ethyl ether A50 resin solution includes a high molecular weight polyvinyl ethyl ether A50 resin and a solvent;

[0033] The high molecular weight polyvinyl ethyl ether A50 resin is prepared by the preparation method described in the first aspect.

[0034] Preferably, the solvent includes any one or a combination of at least two of alcohols, alkanes or aromatic hydrocarbons.

[0035] Preferably, the alcohol includes methanol and / or ethanol.

[0036] Preferably, the alkane includes heptane.

[0037] Preferably, the aromatic hydrocarbon includes toluene.

[0038] Preferably, the solid content of the high molecular weight polyvinyl ethyl ether A50 resin solution is 45% to 60%, such as 45%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, 60%, etc., and specific point values between the above point values. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the range. Among them, the test method for the solid content is: placing the high molecular weight polyvinyl ethyl ether A50 resin solution in an electric heating oven at 110 °C for 3 hours for determination.

[0039] Preferably, the K value of the high molecular weight polyvinyl ethyl ether A50 resin solution is 55 to 65, such as 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, etc., and specific point values between the above point values. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the range. Among them, the test method for the K value is: using an Ubbelohde viscometer and measuring at a constant temperature of 25 °C.

[0040] Preferably, the viscosity of the high molecular weight polyvinyl ethyl ether A50 resin solution at 23 °C is 5000 to 20000 mPa·s, such as 5000 mPa·s, 6000 mPa·s, 7000 mPa·s, 8000 mPa·s, 9000 mPa·s, 10000 mPa·s, 12000 mPa·s, 14000 mPa·s, 16000 mPa·s, 18000 mPa·s, 20000 mPa·s, etc., and specific point values between the above point values. Due to space limitations and for the sake of brevity, the present invention does not exhaustively list the specific point values included in the range. Among them, the test method for the viscosity is: using a rotational viscometer and measuring at a constant temperature of 23 °C.

[0041] The high molecular weight polyvinyl ethyl ether A50 resin solution provided by the present invention has good transparency, with a K value of 55 to 65 and a viscosity of 5000 to 20000 mPa·s, and can meet the usage requirements in fields such as coatings and inks.

[0042] Fourthly, the present invention provides an application of the high molecular weight polyvinyl ethyl ether A50 resin as described in the second aspect or the high molecular weight polyvinyl ethyl ether A50 resin solution as described in the third aspect in coatings or inks.

[0043] Compared with the prior art, the present invention has at least the following beneficial effects:

[0044] The preparation method provided by the present invention is based on low molecular weight polyvinyl ethyl ether. First, a part of vinyl ethyl ether monomer is added for prepolymerization reaction, and then vinyl ethyl ether is added again to continue the reaction, obtaining high molecular weight polyvinyl ethyl ether A50 resin. The present invention adopts bulk polymerization without using solvents, with environmental protection process, simple operation, and excellent product performance. Specific embodiments

[0045] The technical solution of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations to the present invention.

[0046] Unless otherwise specified, the information of some raw materials used in the following examples and comparative examples of the present invention is as follows:

[0047] Low molecular weight polyvinyl ethyl ether: K value is 12;

[0048] Vinyl ethyl ether: purity is 99.5%.

[0049] Example 1

[0050] In this example, a preparation method of high molecular weight polyvinyl ethyl ether A50 resin is provided. The preparation method includes the following steps:

[0051] Add 30 g of low molecular weight polyvinyl ethyl ether and 0.05 g of boron trifluoride ethanol solution with a mass fraction of 50% into a reaction flask, mix evenly, then add 13 g of vinyl ethyl ether, carry out prepolymerization reaction at 25 °C for 15 min, control the system temperature at 25 °C, dropwise add 287 g of vinyl ethyl ether, and control the dropping time to be 8 hours. After dropping, continue to keep the temperature for reaction for 1 hour to obtain the high molecular weight polyvinyl ethyl ether A50 resin.

[0052] In this example, a high molecular weight polyvinyl ethyl ether A50 resin solution is also provided. The preparation method includes the following steps:

[0053] Add 330 g of ethanol to the obtained high molecular weight polyvinyl ethyl ether A50 resin to obtain 660 g of high molecular weight polyvinyl ethyl ether A50 resin solution.

[0054] Example 2

[0055] In this example, a preparation method of high molecular weight polyvinyl ethyl ether A50 resin is provided. The preparation method includes the following steps:

[0056] Add 20 g of low-molecular-weight polyvinyl ethyl ether and 0.08 g of boron trifluoride ethyl ether solution with a mass fraction of 48% into a reaction flask, mix evenly, then add 30 g of vinyl ethyl ether, carry out a prepolymerization reaction at 20 °C for 30 min, control the system temperature at 20 °C, dropwise add 270 g of vinyl ethyl ether, control the dropping time to be 10 hours, and continue the heat preservation reaction for 1 hour after the dropping is completed to obtain the high-molecular-weight polyvinyl ethyl ether A50 resin.

[0057] In this example, a high-molecular-weight polyvinyl ethyl ether A50 resin solution is also provided, and the preparation method includes the following steps:

[0058] Add 320 g of ethanol to the obtained high-molecular-weight polyvinyl ethyl ether A50 resin to obtain 635 g of high-molecular-weight polyvinyl ethyl ether A50 resin solution.

[0059] Example 3

[0060] In this example, a preparation method of a high-molecular-weight polyvinyl ethyl ether A50 resin is provided, and the preparation method includes the following steps:

[0061] Add 10 g of low-molecular-weight polyvinyl ethyl ether and 0.08 g of boron trifluoride methanol solution with a mass fraction of 40% into a reaction flask, mix evenly, then add 10 g of vinyl ethyl ether, carry out a prepolymerization reaction at 10 °C for 20 min, control the system temperature at 10 °C, dropwise add 290 g of vinyl ethyl ether, control the dropping time to be 10 hours, and continue the heat preservation reaction for 1 hour after the dropping is completed to obtain the high-molecular-weight polyvinyl ethyl ether A50 resin.

[0062] In this example, a high-molecular-weight polyvinyl ethyl ether A50 resin solution is also provided, and the preparation method includes the following steps:

[0063] Add 310 g of ethanol to the obtained high-molecular-weight polyvinyl ethyl ether A50 resin to obtain 620 g of high-molecular-weight polyvinyl ethyl ether A50 resin solution.

[0064] Example 4

[0065] In this example, a preparation method of a high-molecular-weight polyvinyl ethyl ether A50 resin is provided, and the preparation method includes the following steps:

[0066] Add 5 g of low molecular weight polyvinyl ethyl ether and 0.08 g of boron trifluoride diethyl ether solution with a mass fraction of 30% into a reaction flask, mix evenly, then add 15 g of vinyl ethyl ether, carry out a prepolymerization reaction at 20 °C for 60 min, control the system temperature at 20 °C, dropwise add 285 g of vinyl ethyl ether, control the dropping time to be 10 hours, and continue the heat preservation reaction for 1 hour after the dropping is completed to obtain the high molecular weight polyvinyl ethyl ether A50 resin.

[0067] In this example, a high molecular weight polyvinyl ethyl ether A50 resin solution is also provided, and the preparation method includes the following steps:

[0068] Add 305 g of toluene to the obtained high molecular weight polyvinyl ethyl ether A50 resin to obtain 608 g of high molecular weight polyvinyl ethyl ether A50 resin solution.

[0069] Comparative Example 1

[0070] In this comparative example, a preparation method of polyvinyl ethyl ether resin is provided, and the preparation method includes the following steps:

[0071] Add 30 g of low molecular weight polyvinyl ethyl ether and 0.05 g of boron trifluoride ethanol solution with a mass fraction of 50% into a reaction flask, mix evenly, control the system temperature at 25 °C, dropwise add 300 g of vinyl ethyl ether, control the dropping time to be 8 hours, and continue the heat preservation reaction for 1 hour after the dropping is completed to obtain the polyvinyl ethyl ether resin.

[0072] In this comparative example, a polyvinyl ethyl ether resin solution is also provided, and the preparation method includes the following steps:

[0073] Add 330 g of ethanol to the obtained polyvinyl ethyl ether resin to obtain 660 g of polyvinyl ethyl ether solution.

[0074] Comparative Example 2

[0075] In this comparative example, a preparation method of polyvinyl ethyl ether A50 resin is provided, and the preparation method includes the following steps:

[0076] Add 20 g of low molecular weight polyvinyl ethyl ether and 0.08 g of boron trifluoride diethyl ether solution with a mass fraction of 48% into a reaction flask, mix evenly, then add 45 g of vinyl ethyl ether, carry out a prepolymerization reaction at 20 °C for 30 min, control the system temperature at 20 °C, dropwise add 255 g of vinyl ethyl ether, control the dropping time to be 10 hours, and continue the heat preservation reaction for 1 hour after the dropping is completed to obtain the polyvinyl ethyl ether A50 resin.

[0077] In this comparative example, a polyvinyl ethyl ether A50 resin solution is also provided, and the preparation method includes the following steps:

[0078] Add 320 g of ethanol to the obtained polyvinyl ethyl ether A50 resin to obtain 632 g of polyvinyl ethyl ether A50 resin solution.

[0079] Comparative Example 3

[0080] In this comparative example, a preparation method of polyvinyl ethyl ether A50 resin is provided, and the preparation method includes the following steps:

[0081] Add 75 g of n-heptane and 2 g of boron trifluoride methanol solution with a mass fraction of 40% to the reaction flask, control the system temperature at 50 °C, dropwise add 300 g of vinyl ethyl ether, and control the dropping time to be 4 hours. After the dropping is completed, continue to keep the temperature for reaction for 1 hour, remove the solvent, and obtain the polyvinyl ethyl ether A50 resin.

[0082] In this comparative example, a polyvinyl ethyl ether A50 resin solution is also provided, and the preparation method includes the following steps:

[0083] Add 300 g of ethanol to the obtained polyvinyl ethyl ether A50 resin to obtain 576 g of polyvinyl ethyl ether A50 resin solution.

[0084] Perform performance tests on the polyvinyl ethyl ether resin solutions provided in the examples and comparative examples. The test methods are as follows:

[0085] (1) K value: Measured at a constant temperature of 25 °C using an Ubbelohde viscometer;

[0086] (2) Solid content: Measured by placing the polyvinyl ethyl ether resin solution in an electric heating oven at 110 °C for 3 hours;

[0087] (3) Viscosity: Measured at a constant temperature of 23 °C using a rotational viscometer.

[0088] The performance test results are shown in Table 1.

[0089] Table 1

[0090] K value Solid content (%) Viscosity (mpa·s) Example 1 59.3 49.8 9075 Example 2 61.3 49.5 10500 Example 3 58.7 50.2 8500 Example 4 61.9 50.1 12100 Comparative Example 1 21.1 49.2 108 Comparative Example 2 28.4 49.3 231 Comparative Example 3 9.8 46.6 53

[0091] As can be seen from Table 1, the polyvinyl ethyl ether resin solutions provided in the examples of the present invention all have a relatively high K value (58.7 - 61.9), that is, the polyvinyl ethyl ether resins prepared by using the preparation methods provided in the examples of the present invention all have a relatively high molecular weight.

[0092] Compared with Example 1, in Comparative Example 1, the pre-polymerization step was not included in the synthesis of polyvinyl ethyl ether resin, and explosive polymerization occurred during the dropping process. The K value of the product was 21.1, significantly lower than that of Example 1 (59.3), the solid content was 49.2%, lower than that of Example 1 (49.8%), and the viscosity was 108 mPa·s, lower than that of Example 1 (9075 mPa·s).

[0093] Compared with Example 2, in Comparative Example 2, the proportion of vinyl ethyl ether added for the first time was too large during the synthesis of polyvinyl ethyl ether resin, and explosive polymerization occurred. The K value of the product was 28.4, lower than that of Example 2 (61.3), the solid content was 49.3%, lower than that of Example 2 (49.5%), and the viscosity was 231 mPa·s, lower than that of Example 2 (10500 mPa·s).

[0094] In Comparative Example 3, polyvinyl ethyl ether resin was synthesized by a conventional method, and both the K value and viscosity of the product were significantly reduced.

[0095] The applicant declares that the present invention uses the above examples to illustrate the high molecular weight polyvinyl ethyl ether A50 resin and its preparation method and application of the present invention. However, the present invention is not limited to the above examples, that is, it does not mean that the present invention must rely on the above examples to be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc. all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing high molecular weight polyvinyl ethyl ether A50 resin, characterized in that: The preparation method comprises the following steps: The low molecular weight polyvinyl ethyl ether and the initiator are mixed, and then the vinyl ethyl ether is added for the first time to carry out a prepolymerization reaction, and then the vinyl ethyl ether is added for the second time to react to obtain the high molecular weight polyvinyl ethyl ether A50 resin; The mass of the vinyl ethyl ether added for the first time accounts for 1% to 10% of the total mass of the vinyl ethyl ether added twice.

2. The preparation method according to claim 1, characterized in that: The K value of the low molecular weight polyvinyl ethyl ether is less than 20; The added amount of the low molecular weight polyvinyl ethyl ether accounts for 1% to 10% of the total weight of the raw materials.

3. The preparation method according to claim 1, characterized in that: The initiator includes any one of Bronsted acid, Lewis acid, and organic metal compound or a combination of at least two thereof; The initiator is added in the form of an initiator solution; The solvent in the initiator solution includes any one of alcohol, phenol, ether, and acetal, or a combination of at least two thereof; The mass percentage of the initiator solution is 10% to 50%.

4. The preparation method according to claim 1, characterized in that: The mass ratio of the total mass of the vinyl ether added for the first time and the second time to the initiator is (5000-13000):1; The temperature of the prepolymerization reaction is 0 to 30° C. The prepolymerization reaction time is 15 to 60 minutes.

5. The preparation method according to claim 1, characterized in that: When adding vinyl ethyl ether for the second time, the system temperature is controlled to be 0-30°C; The second addition of vinyl ether is performed dropwise; The second adding of vinyl ethyl ether specifically comprises: adding vinyl ethyl ether for the second time in a dropwise manner, and controlling the dropping time to be 5 to 10 hours; The reaction time is 8 to 12 hours.

6. The preparation method according to claim 1, characterized in that: The second adding of vinyl ethyl ether and reacting specifically comprises: adding vinyl ethyl ether for the second time in a dropwise manner, and controlling the dropping time to be 5 to 10 hours, and continuing the reaction for 1 to 3 hours after the dropping is completed.

7. A preparation method according to claim 1, characterized in that: The preparation method comprises the following steps: A low molecular weight polyvinyl ethyl ether and an initiator are mixed, and then vinyl ethyl ether is added for the first time, and a prepolymerization reaction is carried out at 0-30°C for 15-60 minutes, and the system temperature is controlled to be 0-30°C. Then, vinyl ethyl ether is added for a second time in a dropwise manner, and the dropwise addition time is controlled to be 5-10 hours. After the dropwise addition is completed, the reaction is continued for 1-3 hours to obtain the high molecular weight polyvinyl ethyl ether A50 resin.

8. A high molecular weight polyvinyl ethyl ether A50 resin, characterized in that: The high molecular weight polyvinyl ethyl ether A50 resin is prepared by the preparation method as claimed in claim 1.

9. A high molecular weight polyvinyl ethyl ether A50 resin solution, characterized in that: The high molecular weight polyethylene ethyl ether A50 resin solution comprises high molecular weight polyethylene ethyl ether A50 resin and a solvent; The high molecular weight polyethylene ethyl ether A50 resin is prepared by the preparation method as claimed in claim 1; The solvent includes any one or a combination of at least two of alcohol, alkane or aromatic hydrocarbon; The solid content of the high molecular weight polyethylene ethyl ether A50 resin solution is 45% to 60%; The K value of the high molecular weight polyvinyl ether A50 resin solution is 55 to 65; The viscosity of the high molecular weight polyvinyl ethyl ether A50 resin solution at 23° C. is 5000 to 20000 mpa·s.

10. Use of the high molecular weight polyvinyl ethyl ether A50 resin as claimed in claim 8 or the high molecular weight polyvinyl ethyl ether A50 resin solution as claimed in claim 9 in coatings or inks.