Fatigue-resistant corrosion-resistant coating material for injection molds and method for producing same

Abstract

The application discloses a kind of fatigue-resistant corrosion-resistant coating materials for injection mold and preparation method thereof, the layer material includes following weight parts raw materials: synergistic additive 60-80 parts, tackifying additive 5-8 parts, 1,6-hexanediol diacrylate 15-20 parts, isobornyl acrylate 25-35 parts and photoinitiator 3-5 parts, when using, by ultraviolet irradiation curing, the polymer molecule can be formed into crosslinked lattice by tackifying additive, lattice structure can penetrate and anchor in the uneven place of mold surface, its lower shrinkage reduces internal stress, crosslinked lattice can make lacquer film more tough, with higher hardness, better wear resistance and impact resistance, the embedding of polysiloxane segment and carborane can further improve the high temperature resistance of coating film, so that when spraying PVD coating, primer will not appear decomposition, yellowing or lose strength, avoid the problem that primer is foamed due to high temperature softening, degradation, meanwhile increase the corrosion resistance of coating film.

Description

Technical Field

[0001] This invention relates to the field of coating preparation technology, specifically to a fatigue-resistant and corrosion-resistant coating material for injection molds and its preparation method. Background Technology

[0002] In modern manufacturing, the performance of injection molds plays a crucial role in product quality. While traditional injection mold materials can meet basic product requirements, long-term use can lead to a decline in overall mold performance due to wear and corrosion, thus affecting product quality and production efficiency. PVD (Physical Vapor Deposition) is an advanced surface treatment technology that uses physical methods (such as arc evaporation and magnetron sputtering) under vacuum conditions to vaporize target materials and deposit them on the workpiece surface to form a high-performance thin film. It can provide a dense and uniform protective layer on the mold surface without altering the mold substrate's properties, thus enabling injection molds to not only possess excellent processing performance but also maintain stable performance in various harsh environments. However, PVD coating application requires a primer. Existing primers are mostly UV-cured primers, which have poor adhesion and, due to their low strength, result in uneven coatings or coating peeling after repeated use, reducing the mold's lifespan. Summary of the Invention

[0003] The purpose of this invention is to provide a fatigue-resistant and corrosion-resistant coating material for injection molds and its preparation method, which solves the problems of poor fatigue resistance and corrosion resistance of coatings at present.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] A method for preparing a fatigue-resistant and corrosion-resistant coating material for injection molds specifically includes the following steps:

[0006] Step A1: Mix toluene diisocyanate, modified additive, dibutyltin laurylate and toluene evenly. Stir and add polyethylene glycol at a speed of 200-300 r / min and a temperature of 40-50℃. After reacting for 2-3 hours, add 1,3-butanediol and continue reacting for 2-3 hours. Then add hydroxyethyl acrylate and p-hydroxyanisole and react for 4-5 hours to obtain the synergistic additive.

[0007] Step A2: Acrylamide and toluene are mixed, and under nitrogen protection, the mixture is stirred and methyldimethoxysilane and caster catalyst are added at a speed of 150-200 r / min and a temperature of 70-80℃, and the reaction is carried out for 6-8 hours to obtain an intermediate. Dimethylvinylchlorosilane, ferric chloride and tetrahydrofuran are mixed, and under nitrogen protection, the mixture is stirred and the intermediate is added at a speed of 120-150 r / min and a temperature of 68-70℃, and the reaction is carried out for 3-5 hours to obtain a thickening additive.

[0008] Step A3: Weigh the following raw materials by weight: 60-80 parts of synergist additive, 5-8 parts of tackifier additive, 15-20 parts of 1,6-hexanediol diacrylate, 25-35 parts of isobornyl acrylate, and 3-5 parts of photoinitiator. Mix the raw materials evenly to obtain a fatigue-resistant and corrosion-resistant coating material for injection molds.

[0009] Furthermore, in step A1, the molar ratio of toluene diisocyanate, modifying additive, polyethylene glycol, 1,3-butanediol, and p-hydroxyanisole is 14:2:8:8:4, the molecular weight of polyethylene glycol is 200, the amount of dibutyltin laurylate is 0.3% of the mass of toluene diisocyanate, and the amount of p-hydroxyanisole is 0.15% of the mass of hydroxyethyl acrylate.

[0010] Furthermore, in step A2, the molar ratio of acrylamide to methyldimethoxysilane is 1:1, the amount of caster catalyst is 0.01% of the mass of methyldimethoxysilane, and the ratio of dimethylvinylchlorosilane, ferric chloride, and intermediate is 30 mmol: 0.3 g: 60 mmol.

[0011] Furthermore, the photoinitiator mentioned in step A3 is a mixture of photoinitiator 1173 and photoinitiator 819 in a mass ratio of 3:2.

[0012] Furthermore, the modified additive is prepared by the following steps:

[0013] Step B1: Mix decborane and acetonitrile, purge with nitrogen, and reflux for 2-3 hours at 150-200 r / min and 85-90℃. Then, cool to 20-25℃, add p-nitrophenylacetylene, and heat to 90-95℃ for 10-15 hours to obtain nitrocarborane. Mix nitrocarborane, glacial acetic acid, and stannous dichloride, purge with nitrogen, and reflux for 8-10 hours at 120-150 r / min and 80-85℃. Then, cool to 20-25℃, add deionized water, stir for 30-40 minutes, and neutralize with sodium hydroxide solution to obtain aminocarborane.

[0014] Step B2: Mix aminocarborane, hexafluoroisopropanol and tetrahydrofuran, purge with nitrogen, stir and add 3,4-epoxy-1-butene at 120-150 r / min and 0-5℃, heat to 50-60℃ and react for 10-15 h to obtain pretreated carborane. Mix trimethylsilyllithium and tetrahydrofuran evenly, purge with nitrogen, stir and add hexamethylcyclotrisiloxane at 120-150 r / min and 0℃, heat to 20-25℃ and react for 6-8 h, then add dimethylchlorosilane and react for 1-1.5 h to obtain polysiloxane.

[0015] Step B3: Mix the pretreated carborane, polysiloxane, caster catalyst and DMF evenly, purge with nitrogen, and react for 6-8 hours at a speed of 150-200 r / min and a temperature of 80-85℃ to obtain modified carborane. Mix the modified carborane, toluene diisocyanate, dibutyltin dilaurate and toluene, and react for 2-3 hours at a speed of 200-300 r / min and a temperature of 50-60℃ to obtain the modified additive.

[0016] Furthermore, in step B1, the molar ratio of decborane and p-nitrophenylacetylene is 1:1, the volume ratio of nitrocarborane, glacial acetic acid, stannous dichloride and deionized water is 0.7 mmol: 20 mL: 11 mmol: 150 mL, and the mass fraction of sodium hydroxide solution is 20%.

[0017] Furthermore, in step B2, the molar ratio of aminocarborane, hexafluoroisopropanol, tetrahydrofuran, and 3,4-epoxy-1-butene is 1 mol:0.5 L:2 L:2 mol, and the molar ratio of lithium trimethylsilanolate, hexamethylcyclotrisiloxane, and dimethylchlorosilane is 1:5:1.

[0018] Furthermore, in step B3, the molar ratio of pretreated carborane to polysiloxane is 1:2, the amount of caster catalyst is 0.01% of the mass of polysiloxane, the molar ratio of modified carborane to toluene diisocyanate is 1:2, and the amount of dibutyltin dilaurate is 0.5% of the mass of toluene diisocyanate.

[0019] The beneficial effects of this invention: The fatigue-resistant and corrosion-resistant coating material for injection molds prepared by this invention includes the following raw materials: synergistic additive, tackifier, 1,6-hexanediol diacrylate, isobornyl acrylate, and photoinitiator. The synergistic additive is prepared by using toluene diisocyanate, modifying additive, polyethylene glycol, and 1,3-butanediol as raw materials to obtain a polyurethane prepolymer, and then adding hydroxyethyl acrylate to end-cap to obtain the synergistic additive. The tackifier is prepared by using acrylamide and methyldimethoxysilane as raw materials, so that the double bond on acrylamide reacts with the Si-H bond on methyldimethoxysilane to obtain an intermediate. The intermediate is reacted with dimethylvinylchlorosilane, so that the methoxysilane bond on the intermediate reacts with the Si-Cl bond on the dimethylvinylsilane to obtain the tackifier.

[0020] The modified additive uses decborane and nitrobenzyl acetylene as raw materials. The acetylene group on nitrobenzyl acetylene undergoes addition with decborane to produce nitroborane. Nitrocarborane is then reduced, converting the nitro group to an amino group to produce aminocarborane. Aminocarborane is then reacted with 3,4-epoxy-1-butene, causing the amino group on aminocarborane to react with the epoxy group on 3,4-epoxy-1-butene to produce pretreated carborane. Trimethylsilyl alcohol is used as an initiator, and hexamethylcyclotrisiloxane is used as a polymerizing agent. Monomers were synthesized to obtain a lithium silanolate organosilicon segment. Dimethylchlorosilane was then added, causing the Si-Cl bond on the dimethylchlorosilane to react with the lithium silanolate, thus obtaining a polysiloxane. Pretreated carborane was then reacted with the polysiloxane, causing the double bond on the pretreated carborane to react with the Si-H bond on the polysiloxane, thus obtaining a modified carborane. The modified carborane was then reacted with toluene diisocyanate, causing the hydroxyl group on the modified carborane to react with an isocyanate group on the toluene diisocyanate, thus obtaining a modified additive.

[0021] During use, the coating is cured by ultraviolet light. The tackifying additives can form a cross-linked network of polymer molecules. The network structure can penetrate and anchor on uneven areas of the mold surface. At the same time, its lower shrinkage rate reduces internal stress. The polar amide groups in the molecular structure enhance the adhesion to the mold. The cross-linked network makes the paint film more tough, with higher hardness, better wear resistance and impact resistance, and can effectively resist stress caused by temperature changes. The embedding of polysiloxane segments and carborane can further improve the high temperature resistance of the coating film, so that the primer will not decompose, yellow or lose strength when spraying PVD coatings. It avoids the problem of the primer softening and degrading at high temperature and bubbling, while increasing the corrosion resistance of the coating film. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1: A method for preparing a fatigue-resistant and corrosion-resistant coating material for injection molds, specifically including the following steps:

[0024] Step A1: Mix toluene diisocyanate, modified additive, dibutyltin laurylate and toluene evenly. Stir and add polyethylene glycol at 200 r / min and 40℃. After reacting for 2 hours, add 1,3-butanediol and continue reacting for 2 hours. Add hydroxyethyl acrylate and p-hydroxyanisole and react for 4 hours to obtain the synergistic additive.

[0025] Step A2: Acrylamide and toluene were mixed, and under nitrogen protection, the mixture was stirred at 150 r / min and 70°C, and methyldimethoxysilane and caster catalyst were added. The reaction was carried out for 6 hours to obtain an intermediate. Dimethylvinylchlorosilane, ferric chloride, and tetrahydrofuran were mixed, and under nitrogen protection, the mixture was stirred at 120 r / min and 68°C, and the intermediate was added. The reaction was carried out for 3 hours to obtain a thickening additive.

[0026] Step A3: Weigh the following raw materials by weight: 60 parts of synergist additive, 5 parts of thickening additive, 15 parts of 1,6-hexanediol diacrylate, 25 parts of isobornyl acrylate and 3 parts of photoinitiator. Mix the raw materials evenly to obtain a fatigue-resistant and corrosion-resistant coating material for injection molds.

[0027] The molar ratio of toluene diisocyanate, modifying additive, polyethylene glycol, 1,3-butanediol and p-hydroxyanisole in step A1 is 14:2:8:8:4, the molecular weight of polyethylene glycol is 200, the amount of dibutyltin laurylate is 0.3% of the mass of toluene diisocyanate, and the amount of p-hydroxyanisole is 0.15% of the mass of hydroxyethyl acrylate.

[0028] The molar ratio of acrylamide and methyldimethoxysilane in step A2 is 1:1, the amount of caster catalyst is 0.01% of the mass of methyldimethoxysilane, and the ratio of dimethylvinylchlorosilane, ferric chloride and intermediate is 30 mmol: 0.3 g: 60 mmol.

[0029] The photoinitiator mentioned in step A3 is a mixture of photoinitiator 1173 and photoinitiator 819 in a mass ratio of 3:2.

[0030] The modified additive is prepared by the following steps:

[0031] Step B1: Mix decborane and acetonitrile, purge with nitrogen, and reflux for 2 hours at 150 r / min and 85°C. Then, cool to 20°C, add p-nitrophenylacetylene, and react for 10 hours at 90°C to obtain nitrocarborane. Mix nitrocarborane, glacial acetic acid, and stannous dichloride, purge with nitrogen, and reflux for 8 hours at 120 r / min and 80°C. Then, cool to 20°C, add deionized water, stir for 30 minutes, and neutralize with sodium hydroxide solution to obtain aminocarborane.

[0032] Step B2: Mix aminocarborane, hexafluoroisopropanol and tetrahydrofuran, purge with nitrogen, stir at 120 r / min and 0 °C, add 3,4-epoxy-1-butene, heat to 50 °C and react for 10 h to obtain pretreated carborane. Mix trimethylsilyl alcohol lithium and tetrahydrofuran evenly, purge with nitrogen, stir at 120 r / min and 0 °C, add hexamethylcyclotrisiloxane, heat to 20 °C and react for 6 h, then add dimethylchlorosilane and react for 1 h to obtain polysiloxane.

[0033] Step B3: Mix the pretreated carborane, polysiloxane, caster catalyst and DMF evenly, purge with nitrogen, and react for 6 hours at 150 r / min and 80 °C to obtain modified carborane. Mix the modified carborane, toluene diisocyanate, dibutyltin dilaurate and toluene, and react for 2 hours at 200 r / min and 50 °C to obtain modified additive.

[0034] The molar ratio of decborane and p-nitrophenylacetylene in step B1 is 1:1, the volume ratio of nitrocarborane, glacial acetic acid, stannous dichloride and deionized water is 0.7 mmol: 20 mL: 11 mmol: 150 mL, and the mass fraction of sodium hydroxide solution is 20%.

[0035] The ratio of aminocarborane, hexafluoroisopropanol, tetrahydrofuran and 3,4-epoxy-1-butene in step B2 is 1 mol:0.5 L:2 L:2 mol, and the molar ratio of lithium trimethylsilanolate, hexamethylcyclotrisiloxane and dimethylchlorosilane is 1:5:1.

[0036] In step B3, the molar ratio of pretreated carborane and polysiloxane is 1:2, the amount of caster catalyst is 0.01% of the mass of polysiloxane, the molar ratio of modified carborane and toluene diisocyanate is 1:2, and the amount of dibutyltin dilaurate is 0.5% of the mass of toluene diisocyanate.

[0037] Example 2: A method for preparing a fatigue-resistant and corrosion-resistant coating material for injection molds, specifically including the following steps:

[0038] Step A1: Mix toluene diisocyanate, modified additive, dibutyltin laurylate and toluene evenly. Stir and add polyethylene glycol at 200 r / min and 45℃. After reacting for 3 hours, add 1,3-butanediol and continue reacting for 2 hours. Add hydroxyethyl acrylate and p-hydroxyanisole and react for 5 hours to obtain the synergistic additive.

[0039] Step A2: Acrylamide and toluene were mixed, and under nitrogen protection, the mixture was stirred at 150 r / min and 75°C, and methyldimethoxysilane and caster catalyst were added. The reaction was carried out for 7 hours to obtain an intermediate. Dimethylvinylchlorosilane, ferric chloride, and tetrahydrofuran were mixed, and under nitrogen protection, the mixture was stirred at 120 r / min and 70°C, and the intermediate was added. The reaction was carried out for 4 hours to obtain a thickening additive.

[0040] Step A3: Weigh the following raw materials by weight: 70 parts of synergist additive, 6.5 parts of thickener additive, 18 parts of 1,6-hexanediol diacrylate, 30 parts of isobornyl acrylate and 4 parts of photoinitiator. Mix the raw materials evenly to obtain a fatigue-resistant and corrosion-resistant coating material for injection molds.

[0041] The molar ratio of toluene diisocyanate, modifying additive, polyethylene glycol, 1,3-butanediol and p-hydroxyanisole in step A1 is 14:2:8:8:4, the molecular weight of polyethylene glycol is 200, the amount of dibutyltin laurylate is 0.3% of the mass of toluene diisocyanate, and the amount of p-hydroxyanisole is 0.15% of the mass of hydroxyethyl acrylate.

[0042] The molar ratio of acrylamide and methyldimethoxysilane in step A2 is 1:1, the amount of caster catalyst is 0.01% of the mass of methyldimethoxysilane, and the ratio of dimethylvinylchlorosilane, ferric chloride and intermediate is 30 mmol: 0.3 g: 60 mmol.

[0043] The photoinitiator mentioned in step A3 is a mixture of photoinitiator 1173 and photoinitiator 819 in a mass ratio of 3:2.

[0044] The modified additive is prepared by the following steps:

[0045] Step B1: Mix decborane and acetonitrile, purge with nitrogen, and reflux for 2.5 h at 150 r / min and 90 °C. Then, cool to 25 °C, add p-nitrophenylacetylene, and heat to 90 °C for 13 h to obtain nitrocarborane. Mix nitrocarborane, glacial acetic acid, and stannous dichloride, purge with nitrogen, and reflux for 9 h at 120 r / min and 85 °C. Then, cool to 20 °C, add deionized water, stir for 35 min, and neutralize with sodium hydroxide solution to obtain aminocarborane.

[0046] Step B2: Mix aminocarborane, hexafluoroisopropanol and tetrahydrofuran, purge with nitrogen, stir at 120 r / min and 5 °C, add 3,4-epoxy-1-butene, heat to 55 °C and react for 15 h to obtain pretreated carborane. Mix trimethylsilyllithium and tetrahydrofuran evenly, purge with nitrogen, stir at 120 r / min and 0 °C, add hexamethylcyclotrisiloxane, heat to 25 °C and react for 7 h, then add dimethylchlorosilane and react for 1.5 h to obtain polysiloxane.

[0047] Step B3: Mix the pretreated carborane, polysiloxane, caster catalyst and DMF evenly, purge with nitrogen, and react for 7 hours at 150 r / min and 85 °C to obtain modified carborane. Mix the modified carborane, toluene diisocyanate, dibutyltin dilaurate and toluene, and react for 3 hours at 200 r / min and 55 °C to obtain modified additive.

[0048] The molar ratio of decborane and p-nitrophenylacetylene in step B1 is 1:1, the volume ratio of nitrocarborane, glacial acetic acid, stannous dichloride and deionized water is 0.7 mmol: 20 mL: 11 mmol: 150 mL, and the mass fraction of sodium hydroxide solution is 20%.

[0049] The ratio of aminocarborane, hexafluoroisopropanol, tetrahydrofuran and 3,4-epoxy-1-butene in step B2 is 1 mol:0.5 L:2 L:2 mol, and the molar ratio of lithium trimethylsilanolate, hexamethylcyclotrisiloxane and dimethylchlorosilane is 1:5:1.

[0050] In step B3, the molar ratio of pretreated carborane and polysiloxane is 1:2, the amount of caster catalyst is 0.01% of the mass of polysiloxane, the molar ratio of modified carborane and toluene diisocyanate is 1:2, and the amount of dibutyltin dilaurate is 0.5% of the mass of toluene diisocyanate.

[0051] Example 3: A method for preparing a fatigue-resistant and corrosion-resistant coating material for injection molds, specifically including the following steps:

[0052] Step A1: Mix toluene diisocyanate, modified additive, dibutyltin laurylate and toluene evenly. Stir and add polyethylene glycol at 300 r / min and 50℃. After reacting for 3 hours, add 1,3-butanediol and continue reacting for 3 hours. Then add hydroxyethyl acrylate and p-hydroxyanisole and react for 5 hours to obtain the synergistic additive.

[0053] Step A2: Acrylamide and toluene were mixed, and under nitrogen protection, methyldimethoxysilane and castor catalyst were added while stirring at 200 r / min and 80°C. The reaction was carried out for 8 hours to obtain an intermediate. Dimethylvinylchlorosilane, ferric chloride and tetrahydrofuran were mixed, and under nitrogen protection, the intermediate was added while stirring at 150 r / min and 70°C. The reaction was carried out for 5 hours to obtain a thickening additive.

[0054] Step A3: Weigh the following raw materials by weight: 80 parts of synergist additive, 8 parts of thickener additive, 20 parts of 1,6-hexanediol diacrylate, 35 parts of isobornyl acrylate and 5 parts of photoinitiator. Mix the raw materials evenly to obtain a fatigue-resistant and corrosion-resistant coating material for injection molds.

[0055] The molar ratio of toluene diisocyanate, modifying additive, polyethylene glycol, 1,3-butanediol and p-hydroxyanisole in step A1 is 14:2:8:8:4, the molecular weight of polyethylene glycol is 200, the amount of dibutyltin laurylate is 0.3% of the mass of toluene diisocyanate, and the amount of p-hydroxyanisole is 0.15% of the mass of hydroxyethyl acrylate.

[0056] The molar ratio of acrylamide and methyldimethoxysilane in step A2 is 1:1, the amount of caster catalyst is 0.01% of the mass of methyldimethoxysilane, and the ratio of dimethylvinylchlorosilane, ferric chloride and intermediate is 30 mmol: 0.3 g: 60 mmol.

[0057] The photoinitiator mentioned in step A3 is a mixture of photoinitiator 1173 and photoinitiator 819 in a mass ratio of 3:2.

[0058] The modified additive is prepared by the following steps:

[0059] Step B1: Mix decborane and acetonitrile, purge with nitrogen, and reflux for 3 hours at 200 r / min and 90°C. Then, cool to 25°C, add p-nitrophenylacetylene, and react for 15 hours at 95°C to obtain nitrocarborane. Mix nitrocarborane, glacial acetic acid, and stannous dichloride, purge with nitrogen, and reflux for 10 hours at 150 r / min and 85°C. Then, cool to 25°C, add deionized water, stir for 40 minutes, and neutralize with sodium hydroxide solution to obtain aminocarborane.

[0060] Step B2: Mix aminocarborane, hexafluoroisopropanol and tetrahydrofuran, purge with nitrogen, stir and add 3,4-epoxy-1-butene at 150 r / min and 5 °C, heat to 60 °C and react for 15 h to obtain pretreated carborane. Mix trimethylsilyl alcohol lithium and tetrahydrofuran evenly, purge with nitrogen, stir and add hexamethylcyclotrisiloxane at 150 r / min and 0 °C, heat to 25 °C and react for 8 h. Then add dimethylchlorosilane and react for 1.5 h to obtain polysiloxane.

[0061] Step B3: Mix the pretreated carborane, polysiloxane, caster catalyst and DMF evenly, purge with nitrogen, and react for 8 hours at 200 r / min and 85 °C to obtain modified carborane. Mix the modified carborane, toluene diisocyanate, dibutyltin dilaurate and toluene, and react for 3 hours at 300 r / min and 60 °C to obtain modified additive.

[0062] The molar ratio of decborane and p-nitrophenylacetylene in step B1 is 1:1, the volume ratio of nitrocarborane, glacial acetic acid, stannous dichloride and deionized water is 0.7 mmol: 20 mL: 11 mmol: 150 mL, and the mass fraction of sodium hydroxide solution is 20%.

[0063] The ratio of aminocarborane, hexafluoroisopropanol, tetrahydrofuran and 3,4-epoxy-1-butene in step B2 is 1 mol:0.5 L:2 L:2 mol, and the molar ratio of lithium trimethylsilanolate, hexamethylcyclotrisiloxane and dimethylchlorosilane is 1:5:1.

[0064] In step B3, the molar ratio of pretreated carborane and polysiloxane is 1:2, the amount of caster catalyst is 0.01% of the mass of polysiloxane, the molar ratio of modified carborane and toluene diisocyanate is 1:2, and the amount of dibutyltin dilaurate is 0.5% of the mass of toluene diisocyanate.

[0065] Comparative Example 1: In this comparative example, aniline was used instead of aminocarborane compared to Example 1, but the other steps were the same.

[0066] Comparative Example 2: Compared with Example 1, this comparative example uses aminocarborane, hexafluoroisopropanol and tetrahydrofuran, under nitrogen protection, stirred and epoxide butane is added at a speed of 120 r / min and a temperature of 0°C, and the temperature is raised to 50°C for 10 h. The product obtained replaces the modified carborane, and the remaining steps are the same.

[0067] Comparative Example 3: This comparative example did not include any thickening additives compared to Example 1, but the remaining steps were the same.

[0068] The coatings prepared in Examples 1-3 and Comparative Examples 1-3 were applied to tinplate with a film thickness of 85 μm. The edges were sealed with paraffin wax to obtain samples. The resistance to neutral salt spray was tested according to GB / T1771-2007, the pencil hardness was tested according to GB / T6739-2022, the impact resistance of the coating at a height of 50 cm was tested according to GB / T1732-2020, and the adhesion of the coating was tested according to GB / T9286-2021. The test results are shown in Table 1 below.

[0069] Table 1

[0070] Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Resistance to neutral salt spray h 1885 1891 1915 1577 1237 1427 Pencil hardness 4H 4H 4H 2H 3H 3H Impact resistance No damage was found to the coating. No damage was found to the coating. No damage was found to the coating. Coating peeling Cracks appeared in the coating Cracks appeared in the coating Adhesion level 0 0 0 1 1 2

[0071] As shown in Table 1, the present invention has excellent adhesion, corrosion resistance and fatigue resistance.

[0072] The above description is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined in the claims, they should all fall within the protection scope of the present invention.

Claims

1. A method for producing a fatigue-resistant corrosion-resistant coating material for injection molds, characterized by: Specifically, the steps include the following: Step A1: Mix and stir toluene diisocyanate, modified additive, dibutyltin laurylate and toluene, add polyethylene glycol, and react. Then add 1,3-butanediol and continue the reaction. Add hydroxyethyl acrylate and p-hydroxyanisole and react to obtain the synergistic additive. Step A2: Mix acrylamide and toluene, purge with nitrogen, stir and add methyldimethoxysilane and caster catalyst to react and obtain an intermediate. Mix dimethylvinylchlorosilane, ferric chloride and tetrahydrofuran, purge with nitrogen, stir and add the intermediate to react and obtain a thickening additive. Step A3: Weigh the following raw materials by weight: 60-80 parts of synergist additive, 5-8 parts of thickener additive, 15-20 parts of 1,6-hexanediol diacrylate, 25-35 parts of isobornyl acrylate and 3-5 parts of photoinitiator. Mix the raw materials evenly to obtain a fatigue-resistant and corrosion-resistant coating material for injection molds. The modified additive is prepared by the following steps: Step B1: Mix decborane and acetonitrile, purge with nitrogen for protection, reflux, cool, add p-nitrophenylacetylene, and react to obtain nitrocarborane. Mix nitrocarborane, glacial acetic acid, and stannous dichloride, purge with nitrogen for protection, reflux, cool, add deionized water, stir, and then add sodium hydroxide solution to neutralize to obtain aminocarborane. Step B2: Mix aminocarborane, hexafluoroisopropanol and tetrahydrofuran, purge with nitrogen, stir and add 3,4-epoxy-1-butene, heat and react to obtain pretreated carborane. Mix trimethylsilyllithium and tetrahydrofuran evenly, purge with nitrogen, stir and add hexamethylcyclotrisiloxane, heat and react, then add dimethylchlorosilane and react to obtain polysiloxane. Step B3: Mix the pretreated carborane, polysiloxane, caster catalyst and DMF evenly, purge with nitrogen for protection, and react to obtain modified carborane. Mix the modified carborane, toluene diisocyanate, dibutyltin dilaurate and toluene and react to obtain the modified additive.

2. The method of claim 1, wherein the method further comprises: The molar ratio of toluene diisocyanate, modified additive, polyethylene glycol, 1,3-butanediol and p-hydroxyanisole in step A1 is 14:2:8:8:

4. ​ 3. The method of claim 1, wherein the method further comprises: applying a primer layer to the surface of the mold; and applying a topcoat layer to the primer layer. The molar ratio of acrylamide and methyldimethoxysilane in step A2 is 1:1, and the ratio of dimethylvinylchlorosilane, ferric chloride and intermediate is 30 mmol: 0.3 g: 60 mmol.

4. The method of claim 1, wherein the method further comprises: applying a primer layer to the surface of the mold; and applying a topcoat layer to the primer layer. The photoinitiator mentioned in step A3 is a mixture of photoinitiator 1173 and photoinitiator 819 in a mass ratio of 3:

2.

5. The method of claim 1, wherein the method further comprises: applying a primer layer to the surface of the mold; and applying a topcoat layer to the primer layer. The molar ratio of decborane and p-nitrophenylacetylene in step B1 is 1:1, and the volume ratio of nitrocarborane, glacial acetic acid, stannous dichloride and deionized water is 0.7 mmol: 20 mL: 11 mmol: 150 mL.

6. The method of claim 1, wherein the method further comprises: applying a primer layer to the surface of the mold; and applying a topcoat layer to the primer layer. The ratio of aminocarborane, hexafluoroisopropanol, tetrahydrofuran and 3,4-epoxy-1-butene in step B2 is 1 mol:0.5 L:2 L:2 mol, and the molar ratio of lithium trimethylsilanolate, hexamethylcyclotrisiloxane and dimethylchlorosilane is 1:5:

1.

7. The method of claim 1, wherein the method further comprises: applying a primer layer to the surface of the mold; and applying a topcoat layer to the primer layer. The molar ratio of the pre-treated carborane and polysiloxane is 1:2, and the molar ratio of the modified carborane and toluene diisocyanate is 1:

2.

8. A fatigue resistant corrosion resistant coating material for injection molding molds characterized by: Prepared according to the method of any one of claims 1-7.