High-molecular impact-resistant protective coating and preparation method thereof

Abstract

The invention discloses a high-molecular impact-resistant protective coating and a preparation method thereof, and belongs to the technical field of high-molecular materials, and the high-molecular impact-resistant protective coating comprises the following raw materials: 30-50 parts by weight of epoxy resin, 15-20 parts by weight of silicon resin, 10-20 parts by weight of an impact-resistant modifier, 7-15 parts by weight of a filler, 2-10 parts by weight of an auxiliary agent and 10-20 parts by weight of a curing agent. By adding sodium lauryl sulfate, the compatibility of polyvinyl alcohol and a coating matrix can be improved, and polyvinyl alcohol can form a net structure in the curing process, so that the toughness and the impact resistance of an impact-resistant modifier are improved, the impact resistance and the hardness of the coating are remarkably improved, and meanwhile, by virtue of a specific filler ratio, the coating has a good application prospect. The barium sulfate, the mica powder, the walnut shell powder and the kaolin are combined with the organic resin, so that good grain composition is realized, an advantage complementary effect is exerted, and a more uniform and compact coating structure is formed, so that the rigidity and the strength of the coating are improved, and meanwhile, when the coating is impacted by external force, stress is effectively dispersed.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a polymer impact-resistant protective coating and its preparation method. Background Technology

[0002] With the rapid development of modern industry, various mechanical equipment, building structures, and transportation vehicles frequently face various external impacts and abrasions during operation. This not only affects their appearance but may also lead to structural damage and even safety accidents. Therefore, effective protection for these equipment and structures is crucial. While traditional protective coatings can provide protection to some extent, they often fall short in terms of impact resistance, abrasion resistance, and corrosion resistance. Especially in extreme environments, such as high temperature, high humidity, and high salt spray, the performance of these coatings deteriorates rapidly, failing to meet long-term stable protection requirements. To improve the performance of protective coatings, researchers have attempted to modify them by adding various fillers and additives. For example, adding abrasion-resistant fillers such as silica and alumina can improve the abrasion resistance of coatings; adding corrosion-resistant fillers such as zinc oxide and zirconium oxide can improve the corrosion resistance of coatings. However, these modification methods often only improve a specific property and cannot simultaneously achieve impact resistance, abrasion resistance, and corrosion resistance.

[0003] Therefore, developing a novel polymer impact-resistant protective coating and its preparation method to achieve a comprehensive improvement in the coating's impact resistance, abrasion resistance, and corrosion resistance is of great practical significance for meeting the growing protection needs of modern industry and construction. Summary of the Invention

[0004] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0005] In view of the problems existing in the above and / or prior art, the present invention is proposed.

[0006] Therefore, the purpose of this invention is to overcome the shortcomings of the prior art and provide a polymer impact-resistant protective coating.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution, comprising the following raw materials: 30-50 parts by weight of epoxy resin, 15-20 parts by weight of silicone resin, 10-20 parts by weight of impact modifier, 7-15 parts by weight of filler, 2-10 parts by weight of additives and 10-20 parts by weight of curing agent. The impact-resistant modifier is prepared by the following method: Sodium lauryl sulfate and polyvinyl alcohol are added to deionized water and heated to 80-100°C. Ammonium persulfate and butadiene monomer are added while stirring. After reacting for 10-15 minutes, heating is stopped, and the mixture is cooled to 60°C at room temperature. An equal amount of ammonium persulfate is added again, and acrylonitrile monomer is added dropwise. The mixture is then allowed to cool naturally to room temperature. When the solution clearly separates into layers, the upper clear liquid is removed. The mixture is then washed repeatedly with deionized water and dried to obtain the impact-resistant modifier.

[0008] As a preferred embodiment of the polymer impact-resistant protective coating of the present invention, the filler includes mica powder, barium sulfate, walnut shell powder, and kaolin.

[0009] As a preferred embodiment of the polymer impact-resistant protective coating of the present invention, the mass ratio of mica powder, barium sulfate, walnut shell powder and kaolin in the filler is 1~2:2~5:1~3:3~5.

[0010] In a preferred embodiment of the polymer impact-resistant protective coating of the present invention, the additives include leveling agents and dispersants.

[0011] In a preferred embodiment of the polymer impact-resistant protective coating of the present invention, the rate of adding acrylonitrile monomer is 10~15 ml / min.

[0012] As a preferred embodiment of the polymer impact-resistant protective coating of the present invention, wherein the mass ratio of sodium lauryl sulfate, polyvinyl alcohol, deionized water, single addition of ammonium persulfate, butadiene monomer and acrylonitrile monomer in the impact-resistant modifier is 1:1~4:20:1~2:50:50.

[0013] Another objective of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a polymer impact-resistant protective coating.

[0014] To solve the above-mentioned technical problems, the present invention provides the following technical solution: including, The raw materials are weighed and mixed in proportion, and then stirred and ball-milled to obtain the protective coating.

[0015] In a preferred embodiment of the preparation method of the polymer impact-resistant protective coating of the present invention, the ball milling speed is 350~400 rpm and the time is 6~24 h.

[0016] Beneficial effects of this invention: This invention improves the compatibility between polyvinyl alcohol (PVA) and the coating matrix by adding sodium lauryl sulfate. During curing, PVA forms a network structure, increasing the toughness and impact resistance of the impact modifier. This significantly enhances the impact resistance and hardness of the coating, while also effectively improving corrosion resistance, thus effectively resisting external impacts and collisions. Furthermore, a specific filler ratio allows barium sulfate, mica powder, walnut shell powder, and kaolin to combine with the organic resin. A reasonable amount of admixtures achieves good particle size distribution, leveraging a "complementary advantage effect" to form a more uniform and dense coating structure. This improves the rigidity and strength of the coating and effectively disperses stress when subjected to external impact, providing additional resistance and absorbing more energy, thereby enhancing the coating's impact resistance. This invention achieves a comprehensive improvement in the coating's impact resistance, abrasion resistance, and corrosion resistance, and has significant practical implications for meeting the growing protective needs of modern industry and construction. Detailed Implementation

[0017] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0018] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0019] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0020] All raw materials used in this invention are industrial grade and, unless otherwise specified, are commercially available in the field.

[0021] The epoxy resin used in this invention is bisphenol A epoxy resin E-12, CAS number 25085-99-8, molecular formula: C 21 H 24O4 was purchased from Shanghai Kaiyin Chemical Co., Ltd., model SM604; the CAS number of the silicone resin used was 67763-03-5, molecular formula: H4Si, purchased from Shanghai Kaiyin Chemical Co., Ltd., model SJ-804; the barium sulfate used was 800 mesh, purchased from Kening New Materials (Shijiazhuang) Co., Ltd.; the mica powder used was 60 mesh, purchased from Chuzhou Baota Sericite Mining Co., Ltd., item number GW; the walnut shell powder used was 60 mesh, purchased from Guangzhou Shengxin Chemical Technology Co., Ltd.; the kaolin used was purchased from Changzhou Antai Chemical Co., Ltd., item number 0002; the leveling agent used was purchased from Suzhou Qingtian New Materials Co., Ltd., model DH-4310; the dispersant used was purchased from Suzhou Qingtian New Materials Co., Ltd., model DH-5350; the curing agent used was purchased from Shenzhen Guanghui New Building Materials Co., Ltd., item number sz1527.

[0022] The impact resistance of the obtained coating was tested in accordance with GB / T1732—2020 "Test Method for Impact Resistance of Coating Film"; The wear resistance of the obtained coating was tested in accordance with GB / T 5478-2008 "Test Method for Rolling Abrasion of Plastics"; The hardness of the obtained coating was tested according to GB / T 3854-2017 "Barcol Hardness Test Method for Reinforced Plastics"; The adhesion properties of the obtained coating were tested in accordance with ISO 4624-2023 "Paints and varnishes - Adhesion pull-off test". The corrosion resistance of the obtained coating was tested in accordance with GB / T 14165-2008 "General requirements for field tests of atmospheric corrosion of metals and alloys".

[0023] Example 1 This embodiment provides a method for preparing an impact-resistant modifier, specifically as follows: 1 part sodium lauryl sulfate and 2 parts polyvinyl alcohol were added to 20 parts deionized water and heated to 80°C. The mixture was stirred and 1 part ammonium persulfate and 50 parts butadiene monomer were added. After reacting for 10 minutes, the heating was stopped and the mixture was cooled to 60°C at room temperature. Another 1 part ammonium persulfate was added and 50 parts acrylonitrile monomer were added dropwise at a rate of 10 ml / min. The mixture was then allowed to cool naturally to room temperature. When the solution clearly separated into layers, the supernatant was removed. The mixture was washed repeatedly with deionized water and then dried to obtain the impact modifier.

[0024] Example 2 This embodiment provides a method for preparing an impact-resistant modifier, specifically as follows: 1 part sodium lauryl sulfate and 3 parts polyvinyl alcohol were added to 20 parts deionized water and heated to 80°C. The mixture was stirred and 1 part ammonium persulfate and 50 parts butadiene monomer were added. After reacting for 10 minutes, the heating was stopped and the mixture was cooled to 60°C at room temperature. 1 part ammonium persulfate was added again and 50 parts acrylonitrile monomer were added dropwise at a rate of 10 ml / min. The mixture was then allowed to cool naturally to room temperature. When the solution clearly separated into layers, the supernatant was removed. The mixture was washed repeatedly with deionized water and then dried to obtain the impact modifier.

[0025] Example 3 This embodiment provides a method for preparing an impact-resistant modifier, specifically as follows: 1 part sodium lauryl sulfate and 3 parts polyvinyl alcohol were added to 20 parts deionized water and heated to 80°C. The mixture was stirred and 2 parts ammonium persulfate and 50 parts butadiene monomer were added. After reacting for 10 minutes, the heating was stopped and the mixture was cooled to 60°C at room temperature. 2 parts ammonium persulfate were added again and 50 parts acrylonitrile monomer were added dropwise at a rate of 10 ml / min. The mixture was then allowed to cool naturally to room temperature. When the solution clearly separated into layers, the supernatant was removed. The mixture was washed repeatedly with deionized water and then dried to obtain the impact modifier.

[0026] Comparative Example 1 Comparative Example 1 provides a method for preparing an impact-resistant modifier, specifically as follows: 1 part sodium lauryl sulfate and 8 parts polyvinyl alcohol were added to 20 parts deionized water and heated to 80°C. The mixture was stirred and 1 part ammonium persulfate and 50 parts butadiene monomer were added. After reacting for 10 minutes, the heating was stopped and the mixture was cooled to 60°C at room temperature. Another 1 part ammonium persulfate was added and 50 parts acrylonitrile monomer were added dropwise at a rate of 10 ml / min. The mixture was then allowed to cool naturally to room temperature. When the solution clearly separated into layers, the supernatant was removed. The mixture was washed repeatedly with deionized water and then dried to obtain the impact modifier.

[0027] Comparative Example 2 Comparative Example 2 provides a method for preparing an impact-resistant modifier, specifically as follows: 1 part sodium lauryl sulfate and 2 parts polyvinyl alcohol were added to 20 parts deionized water and heated to 80°C. The mixture was stirred and 5 parts ammonium persulfate and 50 parts butadiene monomer were added. After reacting for 10 minutes, the heating was stopped and the mixture was cooled to 60°C at room temperature. 5 parts ammonium persulfate were added again and 50 parts acrylonitrile monomer were added dropwise at a rate of 10 ml / min. The mixture was then allowed to cool naturally to room temperature. When the solution clearly separated into layers, the supernatant was removed. The mixture was washed repeatedly with deionized water and then dried to obtain the impact modifier.

[0028] Comparative Example 3 Comparative Example 3 provides a method for preparing an impact-resistant modifier, specifically as follows: 1 part sodium lauryl sulfate and 2 parts polyvinyl alcohol were added to 20 parts deionized water and heated to 80°C. The mixture was stirred and 2 parts ammonium persulfate, 50 parts butadiene monomer, and 50 parts acrylonitrile monomer were added. After reacting for 10 minutes, the heating was stopped and the mixture was allowed to cool naturally to room temperature. When the solution clearly separated into layers, the upper clear liquid was removed. The mixture was then washed repeatedly with deionized water and dried to obtain the impact-resistant modifier.

[0029] Comparative Example 4 Comparative Example 4 provides a method for preparing an impact-resistant modifier, specifically as follows: 1 part sodium lauryl sulfate and 2 parts polyvinyl alcohol were added to 20 parts deionized water and heated to 80°C. The mixture was stirred and 1 part ammonium persulfate and 50 parts acrylonitrile monomer were added. After reacting for 10 minutes, the heating was stopped and the mixture was cooled to 60°C at room temperature. Another 1 part ammonium persulfate was added and 50 parts butadiene monomer were added dropwise at a rate of 10 ml / min. The mixture was then allowed to cool naturally to room temperature. When the solution clearly separated into layers, the supernatant was removed. The mixture was washed repeatedly with deionized water and then dried to obtain the impact modifier.

[0030] Example 4 This embodiment provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 1 part by weight of mica powder, 4 parts by weight of barium sulfate, 2 parts by weight of walnut shell powder, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Example 1.

[0031] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0032] Example 5 This embodiment provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 2 parts by weight of mica powder, 2 parts by weight of barium sulfate, 3 parts by weight of walnut shell powder, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Example 1.

[0033] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0034] Example 6 This embodiment provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 1 part by weight of mica powder, 5 parts by weight of barium sulfate, 3 parts by weight of walnut shell powder, 3 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Example 1.

[0035] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0036] Example 7 This embodiment provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 1 part by weight of mica powder, 4 parts by weight of barium sulfate, 2 parts by weight of walnut shell powder, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Example 2.

[0037] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0038] Example 8 This embodiment provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 1 part by weight of mica powder, 4 parts by weight of barium sulfate, 2 parts by weight of walnut shell powder, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Example 3.

[0039] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0040] The substrate surface was cleaned with acetone, and the protective coatings prepared in Examples 4 to 8 were applied to a thickness of 3 mm in one go at a spraying pressure of 2 MPa, maintaining a coating coverage of not less than 98%. Subsequently, the substrate was air-dried for 48 hours and cured at 450°C for 48 hours. After naturally cooling to room temperature, the substrate surface was rinsed with a high-pressure water gun or high-pressure airflow to remove residues, and then air-dried to obtain the coating. The performance parameters of the coatings prepared in Examples 4 to 8 were measured, and the results are shown in Table 1.

[0041] Table 1

[0042] As shown in Table 1, the polymer impact-resistant protective coatings prepared in the embodiments of the present invention all have good impact resistance, wear resistance, and good hardness and corrosion resistance, as well as strong adhesion. This indicates that the polymer impact-resistant protective coatings prepared in the present invention can be used in high-flow or high-wear environments. Among them, the polymer impact-resistant protective coating prepared in Example 4 has the best impact resistance. This is because the impact-resistant modifier prepared in Example 1 has the best impact-resistant modification ability. The impact-resistant modifier prepared in Example 1 improves the compatibility and dispersibility between the modifier and the coating matrix by introducing sodium lauryl sulfate and polyvinyl alcohol under ammonium persulfate initiation conditions, and enhances the interaction between the modifier and the coating matrix, thereby significantly enhancing the impact resistance of the coating.

[0043] Comparative Example 5 Comparative Example 5 provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 1 part by weight of mica powder, 4 parts by weight of barium sulfate, 2 parts by weight of walnut shell powder, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Comparative Example 1.

[0044] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0045] Comparative Example 6 Comparative Example 6 provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 1 part by weight of mica powder, 4 parts by weight of barium sulfate, 2 parts by weight of walnut shell powder, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Comparative Example 2.

[0046] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0047] Comparative Example 7 Comparative Example 7 provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 1 part by weight of mica powder, 4 parts by weight of barium sulfate, 2 parts by weight of walnut shell powder, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Comparative Example 3.

[0048] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0049] Comparative Example 8 Comparative Example 8 provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 1 part by weight of mica powder, 4 parts by weight of barium sulfate, 2 parts by weight of walnut shell powder, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Comparative Example 4.

[0050] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0051] The performance parameters of the polymer impact-resistant protective coatings prepared in Comparative Examples 5 to 8 were measured and compared with those in Example 4. The results are shown in Table 2.

[0052] Table 2

[0053] As shown in Table 2, excessive polyvinyl alcohol (PVA) in the impact modifier significantly reduces its impact resistance. This is because the network structure formed by excessive PVA during curing is too dense, restricting the movement of molecular chains and reducing the flexibility of the coating. Furthermore, excessive PVA can cause over-crosslinking of the coating, affecting its elongation at break and toughness, making it more susceptible to brittle fracture under impact.

[0054] When adjusting the amount of initiator ammonium persulfate or the order of addition of butadiene monomer and acrylonitrile monomer, the impact resistance, adhesion and corrosion resistance of the resulting coating will decrease significantly. This is because excessive initiator leads to excessive cross-linking of the coating, making it brittle and reducing its impact resistance. Changing the order of monomer addition will change the relative distribution and microphase structure of the two monomers in the copolymer, thus affecting the final performance of the coating.

[0055] Comparative Example 9 Comparative Example 9 provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 3 parts by weight of mica powder, 4 parts by weight of barium sulfate, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Example 1.

[0056] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0057] Comparative Example 10 Comparative Example 10 provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 1 part by weight of mica powder, 3 parts by weight of barium sulfate, 6 parts by weight of walnut shell powder, 2 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Example 1.

[0058] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0059] Comparative Example 11 Comparative Example 11 provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 5 parts by weight of barium sulfate, 2 parts by weight of walnut shell powder, 5 parts by weight of kaolin, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Example 1.

[0060] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0061] Comparative Example 12 Comparative Example 12 provides a method for preparing a polymer impact-resistant protective coating, specifically as follows: 1) Weigh the raw materials according to the following formula: 45 parts by weight of epoxy resin, 15 parts by weight of silicone resin, 13 parts by weight of impact modifier, 12 parts by weight of walnut shell powder, 2 parts by weight of dispersant, 2 parts by weight of leveling agent, and 11 parts by weight of curing agent. The impact-resistant modifier was prepared in Example 1.

[0062] 2) After stirring, the mixture is placed in a planetary ball mill and milled at 400 rpm for 24 hours. After the milling is completed, a uniformly mixed slurry is obtained, which is the coating slurry. The coating slurry is passed through a 150-mesh sieve to obtain the protective coating of this embodiment.

[0063] The performance parameters of the polymer impact-resistant protective coatings prepared in Comparative Examples 9 to 12 were measured and compared with those in Example 4. The results are shown in Table 3.

[0064] Table 3

[0065] As shown in Table 3, the four fillers—mica powder, barium sulfate, walnut shell powder, and kaolin—exhibit better impact and abrasion resistance. This is because the four different fillers can form a good particle size distribution, exerting a "complementary advantage effect" and producing a super-composite synergistic effect. This results in a more uniform and dense coating structure, improving the mechanical properties and durability of the coating. Among them, walnut shell powder, due to its natural fibrous structure, can play a certain reinforcing role in the coating, providing additional toughness and impact resistance. However, when walnut shell powder is added alone, it cannot form a uniform and dense coating, thus affecting the hardness and adhesion of the coating. At the same time, it cannot fully utilize the advantages of walnut shell powder, and is insufficient to achieve the ideal impact and abrasion resistance.

[0066] Meanwhile, the appropriate amount of admixture is the key to preparing coatings with good performance. When the amount is not right, the particle size distribution may be unbalanced, resulting in uneven coating structure and affecting the overall performance of the coating. When the amount is too much, the solvent inside the coating will not evaporate completely, affecting the curing of the coating. When the amount is too little, cracks will appear after the coating is cured, and the performance of the coating will not meet the expected effect.

[0067] Therefore, in the design of coating mix proportions, it is necessary to make reasonable combinations based on the performance characteristics and particle size distribution of different admixtures in order to ensure that the coating can achieve the best performance.

[0068] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A polymer impact-resistant protective coating, characterized in that: The invention comprises the following raw materials: 30 to 50 parts by weight of epoxy resin, 15 to 20 parts by weight of silicone resin, 10 to 20 parts by weight of impact resistance modifier, 7 to 15 parts by weight of filler, 2 to 10 parts by weight of auxiliary agent and 10 to 20 parts by weight of curing agent; The impact resistance modifier is prepared by the following method: Sodium lauryl sulfate and polyvinyl alcohol are added to deionized water and heated to 80-100°C. After stirring, ammonium persulfate and butadiene monomer are added. After reacting for 10-15 minutes, heating is stopped and the mixture is cooled to 60°C at room temperature. An equal amount of ammonium persulfate is added again and acrylonitrile monomer is added dropwise. The mixture is cooled naturally to room temperature. When the solution is obviously stratified, the upper clear liquid is removed, and the mixture is repeatedly washed with deionized water and dried to obtain an impact modifier.

2. The polymer impact-resistant protective coating according to claim 1, characterized in that: The fillers include mica powder, barium sulfate, walnut shell powder and kaolin.

3. The polymer impact-resistant protective coating according to claim 1, characterized in that: The mass ratio of mica powder, barium sulfate, walnut shell powder and kaolin in the filler is 1-2:2-5:1-3:3-5.

4. The polymer impact-resistant protective coating according to claim 1, characterized in that: The auxiliary agents include leveling agents and dispersants.

5. The polymer impact-resistant protective coating according to claim 1, characterized in that: The rate of adding acrylonitrile monomer dropwise is 10-15 ml / min.

6. The polymer impact-resistant protective coating according to claim 1, characterized in that: The mass ratio of sodium lauryl sulfate, polyvinyl alcohol, deionized water, a single addition amount of ammonium persulfate, butadiene monomer and acrylonitrile monomer in the impact resistance modifier is 1:1-4:20:1-2:50:

50.

7. A method for preparing a polymer impact-resistant protective coating according to any one of claims 1 to 6, characterized in that: include, The raw materials are weighed in proportion and mixed, and the protective coating is obtained after stirring and ball milling.

8. The method for preparing the polymer impact-resistant protective coating according to claim 7, characterized in that: The ball milling speed is 350-400 rpm and the time is 6-24 hours.

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