Preparation method of weather-resistant ms resin, ms resin obtained thereby, and application thereof

Abstract

The application discloses a preparation method of weather-resistant MS resin, the MS resin obtained by the method, and application of the MS resin. In the preparation method, the MS resin is produced by copolymerization of methyl methacrylate and styrene, and the production process comprises a batching process, a polymerization process, a devolatilization process, a granulation process and an optional mixing process, and the method is characterized in that an antioxidant compound A is added in at least one of the batching process, the polymerization process and the devolatilization process; the antioxidant compound A comprises a phosphorus-based antioxidant and an optional hindered phenol antioxidant; an antioxidant compound B is added in at least one of the granulation process and the optional mixing process; and the antioxidant compound B comprises a hindered phenol antioxidant and an optional phosphorus-based antioxidant. The application provides a method for preparing the MS resin by adding different compounded antioxidants in different processes and at different stages, so that the MS resin has excellent weather resistance while the yellow value of the MS resin is greatly reduced.

Description

Technical Field

[0001] This invention relates to a methyl methacrylate copolymer, and more particularly to a method for preparing a weather-resistant MS resin and the resulting MS resin, and its applications. Background Technology

[0002] Methyl methacrylate-styrene copolymer resin (MS resin) is a transparent plastic with excellent light transmittance, mainly prepared by free radical polymerization of methyl methacrylate and styrene monomers. Due to its good processability, low moisture absorption, excellent solvent resistance, and lower cost, it is often used as an alternative to polymethyl methacrylate (PMMA resin), such as in automotive light guides and cosmetic packaging.

[0003] However, because methyl methacrylate-styrene copolymer resin contains a large number of benzene vinyl units, the color of MS resin granules and the molded bodies formed by extrusion, injection molding and other processing methods is poor (yellowish). The introduction of styrene structural units will also lead to a decrease in the yellowing resistance of the polymer resin. MS resin is often exposed to light during use, especially in outdoor use scenarios, and may also face the test of high temperature conditions. These factors will accelerate the aging of MS resin, thereby shortening its service life.

[0004] Based on publicly available patents, using antioxidants within a limited dosage range can improve the high yellowness value and poor weather resistance of MS resin to some extent. Related patent reports include CN103987780, CN104245823, CN102257021, and CN115397913. However, the technical solutions proposed in these patents involve adding the antioxidant all at once during one of the following processes: batching, polymerization, devolatilization, granulation, or mixing. This does not consider the consumption of different types of antioxidants during resin production, nor the impact of antioxidant consumption on the color and weather resistance of the polymer resin. Therefore, the existing technology of adding hindered phenolic antioxidants and phosphorus-based antioxidants all at once during MS resin production cannot simultaneously improve both the high yellowness value and poor weather resistance of the resin. Summary of the Invention

[0005] Through continuous research, the inventors have discovered that if antioxidants are added in earlier stages such as the batching, polymerization, and devolatilization processes, the antioxidants, especially hindered phenolic antioxidants, are prone to modification into coloring substances under the high-temperature conditions of the production process, leading to a deterioration in the resin's color. Furthermore, the modification and degradation of these antioxidants result in a reduction in the antioxidant content of the produced MS resin particles, thereby reducing the weather resistance of the MS resin. If antioxidants are added in later stages such as the granulation and mixing processes, the MS resin, due to its high content of styrene copolymer units, already has a high yellowness value under the high-temperature conditions of the earlier stages, especially the devolatilization process. Antioxidants without color-adjusting effects cannot improve this and can only enhance the weather resistance of the MS resin.

[0006] Furthermore, it is well known in the industry that hindered phenolic antioxidants and phosphorus-based antioxidants have a synergistic effect when used together, and the effect is better than using either one alone. However, through in-depth research by the inventors, hindered phenolic antioxidants are more likely to become coloring substances after high-temperature modification and degradation compared to phosphorus-based antioxidants; while phosphorus-based antioxidants are more easily modified and degraded compared to hindered phenolic antioxidants.

[0007] To address the above technical problems, this invention proposes a method for preparing weather-resistant MS resin, the resulting MS resin, and its applications.

[0008] Based on a first aspect of the present invention, a method for preparing a weather-resistant MS resin, wherein the MS resin is produced by copolymerization of methyl methacrylate and styrene, the production process including a batching step, a polymerization step, a devolatilization step, a granulation step, and optionally a mixing step, characterized in that an antioxidant complex A is added in at least one of the batching step, the polymerization step, and the devolatilization step; the antioxidant complex A includes a phosphorus-based antioxidant and optionally a hindered phenolic antioxidant;

[0009] Antioxidant complex B is added in at least one of the granulation process and optionally the mixing process; said antioxidant complex B includes hindered phenolic antioxidants and optionally phosphorus-based antioxidants.

[0010] During the research, it was found that excessive antioxidants would damage the hue and light transmittance of MS resin, while insufficient antioxidants would have a negligible effect on improving the hue and weather resistance of MS resin. Therefore, it is necessary to limit the range of antioxidant dosage in order to maximize the improvement of the hue and weather resistance of MS resin. Preferably, the total content of the hindered phenolic antioxidant is 0.01-0.15% of the total mass of methyl methacrylate and styrene, for example, 0.02%, 0.04%, 0.05%, 0.08%, 0.1%, 0.12%, 0.13%, 0.14%, 0.15%, etc., more preferably 0.02-0.10%; the total content of the phosphorus-based antioxidant is 0.01-0.2% of the total mass of methyl methacrylate and styrene, for example, 0.02%, 0.04%, 0.05%, 0.08%, 0.1%, 0.12%, 0.14%, 0.15%, 0.16%, 0.18%, etc., more preferably 0.02-0.15%.

[0011] MS resin undergoes a high-temperature pipeline transportation and devolatilization process between polymerization and granulation. During this process, the styrene copolymer units in the resin slurry are easily oxidized by high temperatures, generating coloring substances and resulting in a high yellowness value in the final resin. Therefore, it is necessary to add a certain amount of antioxidant in the earlier stages of the process, such as batching, polymerization, and devolatilization, to reduce or avoid this situation. However, although hindered phenolic antioxidants and phosphorus-based antioxidants have a synergistic effect when used together, hindered phenolic antioxidants are prone to becoming coloring substances after high-temperature modification and degradation. Therefore, when adding antioxidants in these earlier stages, it is necessary to reduce the amount of hindered phenolic antioxidants and correspondingly increase the amount of phosphorus-based antioxidants. In some preferred embodiments, in the antioxidant complex A, the amount of hindered phenolic antioxidant is 0-50% of the total mass of hindered phenolic antioxidants, and the amount of phosphorus-based antioxidant is 30-100% of the total mass of phosphorus-based antioxidants, and the amount of hindered phenolic antioxidant does not exceed the amount of phosphorus-based antioxidant.

[0012] Because some antioxidants are consumed during the earlier stages of production, such as batching, polymerization, and devolatilization, which helps reduce the yellowness and improve the hue of the resin, the final resin particles contain significantly less antioxidant than the added amount. This weakens the improvement on the resin's weather resistance. Therefore, it is necessary to add additional antioxidants after the devolatilization process (in processes without prolonged high-temperature production) to further enhance the resin's weather resistance. Furthermore, hindered phenolic antioxidants are often used as primary antioxidants, while phosphorus-based antioxidants are often used as secondary antioxidants. Therefore, when adding antioxidants in these later stages, to ensure effective resin weather resistance, it is necessary to increase the amount of hindered phenolic antioxidants and correspondingly reduce the amount of more easily degradable phosphorus-based antioxidants. Preferably, in the antioxidant complex B, the amount of hindered phenolic antioxidant is 50-100% of the total mass of hindered phenolic antioxidant; the amount of phosphorus-based antioxidant is 0-70% of the total mass of phosphorus-based antioxidant, and the amount of hindered phenolic antioxidant is not less than the amount of phosphorus-based antioxidant.

[0013] In some preferred embodiments, the mass ratio of hindered phenolic antioxidant to phosphorus-based antioxidant in antioxidant complex A is 1:(1-3);

[0014] Preferably, the mass ratio of hindered phenolic antioxidant to phosphorus-based antioxidant in antioxidant complex B is (1-3):1.

[0015] In some preferred embodiments, the hindered phenolic antioxidants include, but are not limited to, one or more of antioxidants 1010, 1076, 330, 3114, 1098, 245, 1790, 1035, 1135, and 565; furthermore, at least a portion of the hindered phenolic antioxidants may be replaced by phosphorus-based antioxidants containing phenolic hydroxyl groups.

[0016] Preferably, the phosphorus-based antioxidant is a phosphite antioxidant, including but not limited to one or more of antioxidant 168, antioxidant 626, antioxidant 636, antioxidant 686, antioxidant TNPP, antioxidant 618, and di[2,4-di(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite.

[0017] In some preferred embodiments, during the batching process, the theoretical amounts of methyl methacrylate and styrene monomer are added to the batching tank, and preferably, nitrogen is used to deoxygenate the material in the batching tank. Based on the total mass of methyl methacrylate and styrene being 100%, the mass ratio of the two is adjusted to be in the range of 15 / 85-85 / 15, preferably in the range of 20 / 80-70 / 30.

[0018] Depending on the reaction conditions and product quality requirements, initiators and chain transfer agents may be used selectively; the initiator is preferably selected from organic peroxide initiators and / or azo initiators, and more preferably the amount of initiator used is 50-300 ppm of the total mass of methyl methacrylate and styrene; the chain transfer agent is preferably selected from C4-C18 aliphatic thiols and / or C6-C11 aromatic thiols, and more preferably the amount of chain transfer agent used is 200-2000 ppm of the total mass of methyl methacrylate and styrene.

[0019] More preferably, the initiator is selected from one or more of tert-butyl peroxide, di-tert-butyl peroxide, di-tert-butyl peroxide, tert-butyl hydrogen peroxide, tert-butyl peroxide, 1,1-bis-(tert-butyl peroxide)cyclohexane, 1,1-bis-(tert-butyl peroxide)-3,3,5-trimethylcyclohexane, and tert-butyl peroxide-3,5,5-trimethylhexanoate.

[0020] More preferably, the chain transfer agent is selected from one or more of n-butanethiol, tert-butanethiol, n-octanethiol, isooctanethiol, n-dodecylthiol, and tert-dodecylthiol.

[0021] Furthermore, without compromising the hue, transparency, and weather resistance of the MS resin, this invention can also use additives such as UV absorbers, colorants, and release agents. The selection and dosage of these additives can be referenced from conventional methods in the field, and will not be elaborated further.

[0022] In some preferred embodiments, considering product quality and production efficiency, the polymerization process can adopt any of the well-known bulk polymerization, solution polymerization, and other general processes. Considering production safety, a continuous bulk polymerization process with a small amount of solvent is preferred. Preferably, the solvent can be one or more of toluene, ethylbenzene, xylene, acetone, butanone, ethyl acetate, butyl acetate, tetrahydrofuran, and N,N-dimethylformamide. The amount of solvent used is, for example, 0-30% of the total mass of methyl methacrylate and styrene.

[0023] In some preferred embodiments, the polymerization processes for bulk polymerization and solution polymerization can be referenced from known literature such as CN114891147B, CN101338001B, CN102336864B, etc.

[0024] In some preferred embodiments, the devolatilizer used in the devolatilization process is one or a combination of flash tanks, drop-type devolatilizers, and vented extruders. Since unreacted monomers and solvents are more easily oxidized than polymers, they not only reduce the resin's weather resistance but also produce odors during processing and practical applications. The devolatilizer is used to remove unreacted monomers and solvents, but excessively high devolatilization temperatures can degrade the resin's color and increase its yellowness value. Therefore, the devolatilizer needs to be set with appropriate vacuum and temperature. Preferably, the vacuum of the devolatilizer is 0 MPa to -0.099 MPa, more preferably -0.030 MPa to -0.099 MPa, and the operating temperature is 150-260°C, more preferably 190-250°C.

[0025] Preferably, the devolatilization process controls the total amount of residual monomers and solvents in the MS resin to below 5000 ppm, more preferably below 2000 ppm, and even more preferably below 1500 ppm. Within this range, the total amount of residual monomers and solvents has a relatively small impact on the weather resistance of the MS resin.

[0026] In some preferred embodiments, the granulation equipment used is one or any combination of a strip granulator, a spray granulator, a water ring granulator, an underwater granulator, and an underwater granulator;

[0027] Preferably, the granulation process involves melting and extruding the copolymer and then cutting it into pellets to obtain plastic pellets with a pellet size of 1-3 mm.

[0028] In some preferred embodiments, the equipment used in the optional mixing process is one or any combination of a single-screw extruder, a twin-screw extruder, a heated roller, a drum mixer, and an internal mixer, preferably a twin-screw extruder, and more preferably a barrel temperature of 200-250°C and a screw speed of 200-500 rpm. The mixing process is generally used for the functional modification of the resin; for example, downstream customers may add functional additives to further co-extrude the resin granules obtained from the granulation process to obtain functionalized modified products.

[0029] In some embodiments of the present invention, the hindered phenolic antioxidant and phosphorus-based antioxidant may be added in a solution, molten, or solid state as monomers or solvents. The appropriate addition method needs to be selected based on the process conditions of different steps. In the batching step, it is preferred to add the monomers or solvents in a solution state; in the polymerization step, it is preferred to add the monomers or solvents in a solution or molten state; in the devolatilization step, it is preferred to add the monomers or solvents in a molten state; in the granulation step, it is preferred to add the monomers or solvents in a molten state; and in the mixing step, it is preferred to add the monomers or solvents in a solid state as a masterbatch. For different addition methods and different processes, it is necessary to select the appropriate mixing method. In the batching process, it is preferred to mix using the agitator equipped in the batching tank. In the polymerization process, if a fully mixed flow reactor with an agitator is used, it is preferred to mix using the agitator. If a reactor without an agitator (such as a plug flow reactor) is used, it is preferred to mix using a static mixer before entering this process. In the devolatilization process, if a devolatilizer without mixing capacity, such as a strip devolatilizer, is used, it is preferred to mix using a static mixer before entering this process. If an extruder-type devolatilizer is used, it is preferred to mix using an extruder. In the granulation and mixing processes, mixing can be carried out directly using an extruder.

[0030] Based on a second aspect of the present invention, a weather-resistant MS resin prepared by the method described above is also provided. The MS resin has a YI value ≤ 1, a b value ≤ 0.7, and after 14 days of UV aging, ΔYI ≤ 2.4 and ΔE ≤ 1.4.

[0031] Based on a third aspect of the present invention, the application of the weather-resistant MS resin prepared by the method described above in transparent materials in the fields of automobiles, electrical appliances, daily chemical products, medical products, and optical lenses is also provided.

[0032] This invention provides a method for preparing MS resin by adding antioxidants in different compound proportions at multiple stages of different processes, which can significantly reduce the yellowness value of MS resin while ensuring that MS resin has excellent weather resistance. Detailed Implementation

[0033] The present invention will be further illustrated below with specific embodiments. These embodiments are merely illustrative and do not limit the scope of the invention.

[0034] Unless otherwise specified, all raw materials used in the following embodiments and comparative examples of this invention can be obtained through commercially available channels.

[0035] The following embodiments and comparative examples of this invention are all operated using the following equipment:

[0036] Ingredient tank: Used in the ingredient mixing process, with an effective volume of 15L;

[0037] Fully mixed flow reactor: used in the polymerization process, with an effective volume of 30L;

[0038] Drop-type devourer: used in the devouring process;

[0039] Pelletizer: Used in the granulation process;

[0040] The testing methods used in the following embodiments of the present invention are as follows:

[0041] (1) Light transmittance: The total light transmittance of a 3mm sheet was tested according to the method in ASTM D1003_13.

[0042] (2) Hue L, a, b, YI test: The test was conducted according to the method in standard ASTM E313-15e1. The Hunterlab VIS instrument was used to evaluate the initial hue of the sample by the b value and YI value. The higher the b value and YI value, the worse the initial hue.

[0043] (3) Weather resistance: at an irradiance of 0.63 W / m 2 After aging for 14 days under the conditions of "wavelength 340nm, light cycle (60℃, 4h), condensation (50℃, 4h)," the transmittance and hue were tested, and the overall color difference ΔE and yellowness value change ΔYI before and after aging were calculated. The weather resistance of the sample was evaluated by the values ​​of ΔE and ΔYI. The higher the values ​​of ΔE and ΔYI, the worse the weather resistance.

[0044]

Example S1

[0045] MS resin is produced according to the following process:

[0046] (1) Ingredients: Add 15 parts by weight of methyl methacrylate, 85 parts by weight of styrene, 30 parts by weight of ethylbenzene, 0.005 parts by weight of tert-butyl peroxide, and 0.15 parts by weight of tert-dodecyl mercaptan to the mixing tank. Then add 0.01 parts by weight of antioxidant 1076 and 0.03 parts by weight of antioxidant 636 to the materials in the mixing tank. Purge nitrogen gas to fully remove oxygen from the tank.

[0047] (2) Polymerization: The reaction liquid is continuously added to the fully mixed flow reactor at a flow rate of 10 kg / h, the temperature inside the reactor is controlled at 145℃, the average residence time is 4h, and the outlet conversion rate is 70%.

[0048] (3) Deviation: The polymerization slurry is continuously fed into a strip devolatilizer. Under the conditions of a devolatilization vacuum of -0.98MPa, a devolatilization temperature of 240℃, and a residence time of 15min, unreacted monomers and solvents and other light components are removed.

[0049] (4) Granulation: After the devolatilized polymer and 0.04 parts by weight of antioxidant 1076 and 0.02 parts by weight of antioxidant 168 are mixed in a static mixer, the mixture is extruded and granulated by a strip granulator to obtain MS resin with a particle size of 1-3 mm.

[0050]

Examples S2-S6

[0051] MS resin was prepared according to the different conditions in Table 1, and other conditions were as described in Example S1.

[0052] Table 1. Timing and dosage of material addition in different embodiments (unit: parts by mass)

[0053]

[0054] Comparative Example D1

[0055] MS resin was produced using a method essentially the same as that used in Example S1, except that antioxidant 1076 and antioxidant 636 were added in the batching process at 0.05 parts by weight each, and no antioxidants were added in the granulation process.

[0056] Comparative Example D2

[0057] MS resin was produced using a method essentially the same as that used in Example S1, except that no antioxidants were added during the batching process, and the amount of antioxidants 1076 and 168 added during the granulation process was changed to 0.05 parts by weight.

[0058] Comparative Example D3

[0059] MS resin was produced using a method essentially the same as that used in Example S1, except that antioxidant 1076 and antioxidant 636 were added in 0.12 parts by weight each during the batching process, and no antioxidants were added during the granulation process.

[0060] Comparative Example D4

[0061] MS resin was produced using a method that was essentially the same as in Example S1, except that antioxidant 1076 and antioxidant 168 were not added in the batching and granulation processes.

[0062] The performance of the MS resins prepared in each embodiment and comparative example was evaluated, and the results are shown in Table 2. As can be seen from the test results in Table 2, compared with the methyl methacrylate-styrene copolymer resins prepared without antioxidants and with antioxidants added only once, the methyl methacrylate-styrene copolymer resin prepared using the method proposed in this invention, which involves adding antioxidants in specific proportions at multiple stages, has lower initial b-values ​​and YI values, indicating better initial hue; furthermore, the values ​​of ΔE and ΔYI before and after aging are lower, indicating better weather resistance. In addition, the comparison results between Comparative Example D3 and Example S1 show that although using more antioxidants in the earlier stages can improve the weather resistance of the resin, it severely damages the initial hue and light transmittance of the resin.

[0063] Table 2. Performance Evaluation Results

[0064]

[0065] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and additions without departing from the method of the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a weather-resistant MS resin, wherein the MS resin is produced by copolymerization of methyl methacrylate and styrene, and the production process includes a batching step, a polymerization step, a devolatilization step, a granulation step, and optionally a mixing step, characterized in that, Antioxidant complex A is added in at least one of the batching, polymerization, and devolatilization processes; said antioxidant complex A comprises a phosphorus-based antioxidant and optionally a hindered phenolic antioxidant. Antioxidant complex B is added in at least one of the granulation process and optionally the mixing process; said antioxidant complex B includes hindered phenolic antioxidants and optionally phosphorus-based antioxidants; In the antioxidant complex A, the amount of hindered phenolic antioxidant is 0-50% of the total mass of hindered phenolic antioxidant, the amount of phosphorus antioxidant is 30-100% of the total mass of phosphorus antioxidant, and the amount of hindered phenolic antioxidant is no more than the amount of phosphorus antioxidant. In the antioxidant complex B, the amount of hindered phenolic antioxidant is 50-100% of the total mass of hindered phenolic antioxidant; the amount of phosphorus-based antioxidant is 0-70% of the total mass of phosphorus-based antioxidant, and the amount of hindered phenolic antioxidant is not less than the amount of phosphorus-based antioxidant.

2. The method for preparing the weather-resistant MS resin according to claim 1, characterized in that, The total content of the hindered phenolic antioxidant is 0.01-0.15% of the total mass of methyl methacrylate and styrene.

3. The method for preparing the weather-resistant MS resin according to claim 2, characterized in that, The total content of the hindered phenolic antioxidant is 0.02-0.10% of the total mass of methyl methacrylate and styrene.

4. The method for preparing the weather-resistant MS resin according to claim 2, characterized in that, The total content of the phosphorus-based antioxidant is 0.01-0.2% of the total mass of methyl methacrylate and styrene.

5. The method for preparing the weather-resistant MS resin according to claim 4, characterized in that, The total content of the phosphorus-based antioxidant is 0.02-0.15% of the total mass of methyl methacrylate and styrene.

6. The method for preparing the weather-resistant MS resin according to any one of claims 1-5, characterized in that, The mass ratio of hindered phenolic antioxidant to phosphorus-based antioxidant in antioxidant complex A is 1:(1-3).

7. The method for preparing the weather-resistant MS resin according to claim 6, characterized in that, The mass ratio of hindered phenolic antioxidant to phosphorus-based antioxidant in antioxidant complex B is (1-3):

1.

8. The method for preparing the weather-resistant MS resin according to any one of claims 1-5, characterized in that, The hindered phenolic antioxidant is selected from one or more of antioxidants 1010, 1076, 330, 3114, 1098, 245, 1790, 1035, 1135, and 565.

9. The method for preparing the weather-resistant MS resin according to claim 8, characterized in that, The phosphorus-based antioxidant is a phosphite antioxidant.

10. The method for preparing the weather-resistant MS resin according to claim 9, characterized in that, The phosphite antioxidant is selected from one or more of antioxidant 168, antioxidant 626, antioxidant 636, antioxidant 686, antioxidant TNPP, antioxidant 618, and di[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite.

11. The method for preparing the weather-resistant MS resin according to any one of claims 1-5, characterized in that, In the ingredient preparation process, the total mass of methyl methacrylate and styrene is taken as 100%, and the mass ratio between the two is adjusted within the range of 15 / 85-85 / 15.

12. The method for preparing the weather-resistant MS resin according to claim 11, characterized in that, In the ingredient preparation process, the mass ratio of methyl methacrylate and styrene is adjusted within the range of 20 / 80-70 / 30, taking the total mass of methyl methacrylate and styrene as 100%.

13. The method for preparing the weather-resistant MS resin according to claim 11, characterized in that, The copolymer raw materials may also optionally include initiators and chain transfer agents.

14. The method for preparing the weather-resistant MS resin according to claim 13, characterized in that, The initiator is selected from organic peroxide initiators and / or azo initiators.

15. The method for preparing the weather-resistant MS resin according to claim 14, characterized in that, The amount of the initiator used is 50-300 ppm of the total mass of methyl methacrylate and styrene.

16. The method for preparing the weather-resistant MS resin according to claim 13, characterized in that, The chain transfer agent is selected from C4-C18 aliphatic thiols and / or C6-C11 aromatic thiols.

17. The method for preparing the weather-resistant MS resin according to claim 16, characterized in that, The chain transfer agent is used at a concentration of 200-2000 ppm of the total mass of methyl methacrylate and styrene.

18. The method for preparing the weather-resistant MS resin according to any one of claims 1-5, characterized in that, The polymerization process can be any one of bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization.

19. The method for preparing the weather-resistant MS resin according to claim 18, characterized in that, The polymerization process employs either bulk polymerization or solution polymerization.

20. The method for preparing the weather-resistant MS resin according to claim 18, characterized in that, The polymerization process employs a continuous bulk polymerization process in the presence of a small amount of solvent.

21. The method for preparing the weather-resistant MS resin according to any one of claims 1-5, characterized in that, In the devolatilization process, the devolatilizer used is one of the following: flash tank, strip devolatilizer, vented extruder, or any combination thereof.

22. The method for preparing the weather-resistant MS resin according to claim 21, characterized in that, The vacuum degree of the devolatilizer is 0 MPa to -0.099 MPa, and the operating temperature is 150-260℃.

23. The method for preparing the weather-resistant MS resin according to claim 21, characterized in that, The vacuum degree of the devolatilizer is -0.030MPa to -0.099MPa, and the operating temperature is 190-250℃.

24. The method for preparing the weather-resistant MS resin according to claim 21, characterized in that, The devolatilization process controls the total amount of residual monomers and solvents in the MS resin to below 5000 ppm.

25. The method for preparing the weather-resistant MS resin according to claim 24, characterized in that, The devolatilization process controls the total amount of residual monomers and solvents in the MS resin to below 2000 ppm.

26. The method for preparing the weather-resistant MS resin according to claim 25, characterized in that, The devolatilization process controls the total amount of residual monomers and solvents in the MS resin to below 1500 ppm.

27. The method for preparing the weather-resistant MS resin according to any one of claims 1-5, characterized in that, In the granulation process, the granulation equipment used is one of the following: a strip granulator, a spray granulator, a water ring granulator, an underwater granulator, or an underwater granulator, or any combination thereof.

28. The method for preparing the weather-resistant MS resin according to claim 27, characterized in that, The granulation process involves melting and extruding the copolymer, then cutting it into pellets to obtain plastic granules with a particle size of 1-3 mm.

29. The method for preparing the weather-resistant MS resin according to any one of claims 1-5, characterized in that, In the optional mixing process, the equipment used is one or any combination of a single-screw extruder, a twin-screw extruder, a heated roller, a drum mixer, and an internal mixer.

30. A weather-resistant MS resin prepared by the method according to any one of claims 1-29.

31. The application of a weather-resistant MS resin prepared by the method according to any one of claims 1-29 in transparent materials in the fields of automobiles, electrical appliances, daily chemical products, medical products, and optical lenses.

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