Solvent-resistant antirust anticorrosive biological resin coating and preparation method thereof

Abstract

The invention relates to the field of coatings, and discloses a solvent-resistant antirust anticorrosive biological resin coating and a preparation method thereof, the biological resin coating comprises modified bio-based epoxy resin, modified graphene oxide, modified nano titanium dioxide, a curing agent and a diluent; the modified bio-based epoxy resin is prepared by modifying epoxidized polysiloxane formed by self-polymerization of siloxane; the modified nano titanium dioxide is prepared by modifying a fluorine-containing group; the modified graphene oxide is prepared by grafting a flame-retardant modifier on the surface of graphene oxide, the flame-retardant modifier is prepared by reacting 3-amino-1, 2, 4-triazole with phosphonitrilic chloride trimer to prepare a flame-retardant intermediate, then grafting the flame-retardant intermediate and gamma-aminopropyltriethoxysilane by taking terephthalaldehyde as a bridging agent, and further reacting with DOPO (9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide). The prepared biological resin coating is high in adhesive force, high in pencil hardness and good in corrosion resistance, solvent resistance and flame retardant effect.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and in particular relates to a solvent-resistant, rust-proof and corrosion-resistant bio-resin coating and a preparation method thereof. Background Art

[0002] At present, the polymer industry is heavily dependent on fossil raw materials. It is constrained by factors such as rising fossil resource prices, climate change, carbon dioxide emissions and environmental protection, which have seriously hindered the development of polymers and related industries. Bio-based polymers made from biomass resources are widely available and environmentally friendly, and are receiving more and more attention. Among them, epoxy resin, as an important thermosetting polymer, is widely used in coatings, adhesives, electronic components, architectural decoration and other fields due to its good mechanical properties, adhesion, thermal properties, chemical stability, electrical insulation and low curing shrinkage.

[0003] Epoxy resin is one of the most widely used thermosetting resins, with an annual global production of about 2 million tons, of which bisphenol A epoxy resin accounts for more than 85%. It is mainly made from two raw materials, bisphenol A and epichlorohydrin. Epichlorohydrin can be made from bio-based glycerol and has been industrialized, but more than 67% of bisphenol A is currently completely dependent on petrochemical resources. At the same time, bisphenol A poses a great threat to the health of living organisms. The development of environmentally friendly resins that can replace bisphenol A epoxy resin is of great significance. At the same time, epoxy resin has a low limiting oxygen index and can burn in the air after ignition, and the burning rate is relatively fast.

[0004] Environmentally friendly bio-based epoxy resin is a thermosetting resin with significant advantages in resource renewability, environmental compatibility, and molecular structure characteristics. It has attracted widespread attention as an alternative to traditional petroleum-based epoxy resins. As a new type of bio-sourced resin, bio-based epoxy resin can be obtained mainly through the development of renewable resources, such as through the epoxidation of renewable precursors such as vegetable oil, vanillin, lignin, cardanol, and itaconic acid, which can greatly reduce the consumption of petroleum resources. Compared with petroleum-based epoxy resins, bio-based epoxy resins have equally excellent properties, but they are also flammable, which greatly limits their application in transportation, construction, electronics and other fields. In addition, it is easy to form micropores on the surface of the epoxy resin coating during the curing process to form a three-dimensional cross-linked network. The resulting pores will seriously affect the ability of the epoxy resin to block the medium, thereby causing corrosion and limiting the widespread application of the coating. Summary of the invention

[0005] In order to solve the deficiencies mentioned in the above background technology, the purpose of the present invention is to provide a solvent-resistant, rust-proof and corrosion-resistant bio-resin coating and a preparation method thereof, which takes modified bio-based epoxy resin as a substrate, adds modified graphene oxide and modified nano-titanium dioxide, and the prepared coating has strong adhesion, high pencil hardness, good corrosion resistance, solvent resistance and flame retardant effect.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A solvent-resistant, rust-proof and corrosion-resistant bio-resin coating comprises the following raw materials in parts by weight: 50 to 70 parts of modified bio-based epoxy resin, 2 to 5 parts of modified graphene oxide, 10 to 15 parts of modified nano titanium dioxide, 20 to 30 parts of a curing agent, and 10 to 20 parts of a diluent;

[0008] The modified bio-based epoxy resin is made of an epoxidized polysiloxane-modified bio-based epoxy resin formed by self-polymerization of γ-glycidyloxypropyltrimethoxysilane; the modified nano-titanium dioxide is made by grafting fluorine-containing groups with nano-titanium dioxide;

[0009] The modified graphene oxide is prepared by grafting a flame retardant modifier on the surface of graphene oxide, wherein the flame retardant modifier is prepared by a substitution reaction between 3-amino-1,2,4-triazole and hexachlorocyclotriphosphazene to prepare a flame retardant intermediate, and then terephthalaldehyde is used as a bridging agent to graft the flame retardant intermediate and γ-aminopropyltriethoxysilane, and further an addition reaction is carried out with DOPO to prepare the modified graphene oxide.

[0010] Preferably, the curing agent is a mixture of one or more of triethylenetetramine, 4,4'-diaminodiphenylmethane, and meta-xylylenediamine; and the diluent is a mixture of one or more of toluene, xylene, acetone, and butanone.

[0011] Preferably, the method for preparing the modified bio-based epoxy resin comprises the following steps:

[0012] A. Dissolve vanillin and tyramine in anhydrous ethanol, and reflux at 55-70° C. for 4-5 hours. After the reaction is completed, filter and dry to prepare component 1.

[0013] B. Component 1 and tetrabutylammonium bromide are dissolved in epichlorohydrin, and refluxed at 75-85°C for 4-6 hours, then cooled to 45-60°C, and sodium hydroxide solution is added dropwise to continue the reaction for 2-4 hours. After the reaction is completed, the solid is filtered out, and then dilute with dichloromethane, and washed with distilled water. The organic solution obtained after separation is subjected to rotary evaporation and reduced pressure distillation to remove the solvent, and a bio-based epoxy resin is prepared;

[0014] C. Dissolve γ-glycidyloxypropyltrimethoxysilane in a mixed solution of ethanol and deionized water, and continue stirring for 15 to 30 minutes. Then add hydrochloric acid and continue stirring and reacting for 20 to 24 hours. After the reaction is completed, rotary evaporate to obtain epoxidized polysiloxane. Add bio-based epoxy resin to the epoxidized polysiloxane, place at 55 to 70° C. and stir for 5 to 8 hours to prepare modified bio-based epoxy resin.

[0015] Preferably, the method for preparing the modified graphene oxide comprises the following steps:

[0016] (1) Hexachlorocyclotriphosphazene is placed in a reactor, acetonitrile is added to dissolve the mixture, the temperature is raised to 45 to 60° C., 3-amino-1,2,4-triazole is added to deionized water to dissolve the mixture, and the mixture is added to the reactor, the mixture is stirred and mixed evenly, and then solid sodium hydroxide is added to the reactor, and the mixture is condensed and refluxed for 5 to 6 hours. After the reaction is completed, the mixture is subjected to rotary evaporation, washing, and drying to obtain a flame retardant intermediate.

[0017] (2) taking the flame retardant intermediate and γ-aminopropyltriethoxysilane into a reactor, adding ethanol solvent to ultrasonically disperse them uniformly, taking terephthalaldehyde and adding ethanol to dissolve it, and then adding it into the reactor, placing it at 55-65° C. for reflux reaction for 4-7 hours, then taking DOPO and adding ethanol to dissolve it, and then adding it into the reactor, heating it to 75-85° C., and continuing the reaction for 5-7 hours. After the reaction is completed, filtering, washing, and drying, a flame retardant modifier is prepared;

[0018] (3) Ultrasonic dispersion of graphene oxide in anhydrous ethanol, adding a flame retardant modifier, stirring the mixture at 100 to 125° C. in a nitrogen atmosphere for 8 to 12 hours, and filtering, washing, and drying the mixture after the reaction is completed to obtain modified graphene oxide.

[0019] Preferably, in step (1), the molar ratio of hexachlorocyclotriphosphazene to 3-amino-1,2,4-triazole is 1:6 to 6.5.

[0020] Preferably, in step (2), the molar ratio of the flame retardant intermediate, γ-aminopropyltriethoxysilane, terephthalaldehyde and DOPO is 1:6-6.3:6-6.3:12-12.5.

[0021] Preferably, in step (3), the mass ratio of graphene oxide to flame retardant modifier is 1:0.5-1.

[0022] Preferably, the preparation method of the modified nano titanium dioxide comprises the following steps: taking 1H, 1H, 2H, 2H-perfluorodecyltrimethoxysilane, anhydrous ethanol and deionized water in a reactor, stirring and mixing for 0.5 to 1 hour, then adding nano titanium dioxide, and continuing to stir for 1 to 1.5 hours to prepare modified nano titanium dioxide.

[0023] The preparation method of the solvent-resistant, anti-rust and anti-corrosion bio-resin coating as described above comprises the following steps: weighing each weight portion of raw materials, mixing the modified bio-based epoxy resin and the diluent evenly, and then adding modified graphene oxide, modified nano titanium dioxide and a curing agent and stirring evenly to prepare the solvent-resistant, anti-rust and anti-corrosion bio-resin coating.

[0024] Beneficial effects of the present invention:

[0025] The invention uses vanillin, tyramine and epichlorohydrin as raw materials to prepare a bio-based epoxy resin containing a Schiff base structure, which has good degradability. In addition, the invention uses siloxane to undergo a self-polymerization reaction to form an epoxidized polysiloxane, which can form a highly cross-linked network structure through ring-opening polymerization of epoxy groups, so that it can be co-cured with a curing agent containing an amino group together with the bio-based epoxy resin to form two cross-linked networks, thereby enhancing the compactness of the coating, improving its anticorrosion effect and interface adhesion, and the introduced polysiloxane structure can improve the hydrophobicity and wear resistance of the coating, and the polysiloxane is used together with modified nano titanium dioxide modified by perfluorodecyltrimethoxysilane to form a super-hydrophobic surface of the coating by using the strong hydrophobicity of the fluorine-containing group and the siloxane, thereby reducing the direct contact between the coating and the corrosive environment, achieving the purposes of anticorrosion, corrosion prevention and self-cleaning, and further improving the durability of the coating.

[0026] The invention utilizes six P-Cl bonds in the structure of hexachlorocyclotriphosphazene to undergo substitution reaction with -NH groups in the structure of 3-amino-1,2,4-triazole respectively to prepare a flame retardant intermediate, and then uses the flame retardant intermediate, terephthalaldehyde and γ-aminopropyltriethoxysilane as raw materials, and utilizes chemical reaction to make six amino groups in the structure of the flame retardant intermediate to undergo Schiff base reaction with aldehyde groups at one end of terephthalaldehyde to generate N=CH groups, and at the same time, the amino groups in the structure of γ-aminopropyltriethoxysilane undergo Schiff base reaction with aldehyde groups at the other end of terephthalaldehyde to generate N=CH groups, and then utilizes PH bonds in the DOPO structure to undergo addition reaction with N=CH groups to prepare a flame retardant intermediate containing multiple phosphorus elements and nitrogen elements. The flame retardant modifier imparts excellent flame retardant effect to the coating, and utilizes the silicon hydroxyl group introduced in the structure of the flame retardant modifier to undergo condensation reaction with graphene oxide to prepare modified graphene oxide, thereby combining the flame retardant modifier with graphene oxide through a strong chemical bond, avoiding the problems of migration and seepage of the flame retardant modifier, and ensuring that the coating achieves a long-term flame retardant effect. In addition, the grafting reaction expands the interlayer spacing of graphene oxide, thereby making the path for the corrosive medium to reach the epoxy resin matrix to become tortuous, and at the same time is beneficial to improving the dispersion uniformity of graphene oxide, increasing the contact area between graphene oxide and the epoxy resin matrix, and improving the compatibility between graphene oxide and the epoxy resin matrix, so that the comprehensive performance of graphene oxide can be fully exerted. DETAILED DESCRIPTION

[0027] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1 A method for preparing a modified bio-based epoxy resin comprises the following steps:

[0029] A. Dissolve 15.2 g of vanillin and 13.7 g of tyramine in 150 mL of anhydrous ethanol, and reflux at 60° C. for 4 h. After the reaction is complete, filter and dry to prepare component 1.

[0030] B. Take 27.1g of component 1 and 3.2g of tetrabutylammonium bromide and dissolve them in 80mL of epichlorohydrin, place them under reflux at 80°C for 4h, then cool to 50°C, drop 16g of 40% sodium hydroxide solution by mass and continue to react for 3h. After the reaction is completed, filter to remove the solid, then add 60mL of dichloromethane to dilute, and wash with distilled water. The organic solution obtained after separation is subjected to rotary evaporation and reduced pressure distillation to remove the solvent to prepare a bio-based epoxy resin;

[0031] C. Take 10g of γ-glycidyloxypropyltrimethoxysilane and dissolve it in a mixed solution of 18mL of ethanol and 2mL of deionized water, continue stirring for 30min, then add 0.5mL of hydrochloric acid and continue stirring and reacting for 24h. After the reaction is completed, rotary evaporate to obtain epoxidized polysiloxane, add bio-based epoxy resin to the epoxidized polysiloxane, place it at 60°C and stir and mix for 7h to prepare modified bio-based epoxy resin.

[0032] Embodiment 2 A method for preparing modified graphene oxide comprises the following steps:

[0033] (1) 0.87 g of hexachlorocyclotriphosphazene was placed in a reactor, 50 mL of acetonitrile solvent was added to dissolve, the temperature was raised to 55° C., 1.26 g of 3-amino-1,2,4-triazole was added to 50 mL of deionized water to dissolve, and then added to the reactor, stirred and mixed evenly, and then 0.6 g of sodium hydroxide solid was added, and the reaction was condensed and refluxed for 5 hours. After the reaction was completed, the reaction was rotary evaporated, washed, and dried to prepare a flame retardant intermediate;

[0034] (2) 6.3 g of the flame retardant intermediate and 13.3 g of γ-aminopropyltriethoxysilane were placed in a reactor, 50 mL of ethanol solvent was added and ultrasonically dispersed uniformly, 8.3 g of terephthalaldehyde was added to 50 mL of ethanol to dissolve and then added to the reactor, and refluxed at 65 ° C for 7 h, and then 26.1 g of DOPO was added to 100 mL of ethanol to dissolve and then added to the reactor, and the temperature was raised to 85 ° C, and the reaction was continued for 6 h. After the reaction was completed, it was filtered, washed, and dried to prepare a flame retardant modifier;

[0035] (3) 5 g of graphene oxide was ultrasonically dispersed in 120 mL of anhydrous ethanol, and then 3.1 g of a flame retardant modifier was added. The mixture was stirred and reacted at 125 °C in a nitrogen atmosphere for 10 h. After the reaction was completed, the modified graphene oxide was prepared by filtering, washing, and drying.

[0036] Embodiment 3 A method for preparing modified nano titanium dioxide comprises the following steps:

[0037] 2 mL of 1H, 1H, 2H, 2H-perfluorodecyltrimethoxysilane, 50 mL of anhydrous ethanol and 5 mL of deionized water were placed in a reactor and stirred for 1 h. Then 3.5 g of nano-titanium dioxide was added and stirred for 1 h to prepare modified nano-titanium dioxide.

[0038] Example 4 A solvent-resistant, rust-proof and anti-corrosion bio-resin coating comprises the following raw materials in parts by weight: 54 parts of the modified bio-based epoxy resin prepared in Example 1, 2 parts of the modified graphene oxide prepared in Example 2, 10 parts of the modified nano-titanium dioxide prepared in Example 3, 21 parts of the curing agent 4,4'-diaminodiphenylmethane, and 12 parts of the diluent acetone.

[0039] The preparation method of the above-mentioned solvent-resistant, anti-rust and anti-corrosion bio-resin coating comprises the following steps: weighing each weight portion of raw materials, mixing the modified bio-based epoxy resin and the diluent evenly, and then adding modified graphene oxide, modified nano titanium dioxide and a curing agent and stirring evenly to prepare a solvent-resistant, anti-rust and anti-corrosion bio-resin coating.

[0040] Example 5 A solvent-resistant, rust-proof and anti-corrosion bio-resin coating comprises the following raw materials in parts by weight: 61 parts of modified bio-based epoxy resin prepared in Example 1, 3 parts of modified graphene oxide prepared in Example 2, 12 parts of modified nano-titanium dioxide prepared in Example 3, 25 parts of curing agent 4,4'-diaminodiphenylmethane, and 14 parts of diluent acetone.

[0041] The preparation method of the above-mentioned solvent-resistant, rust-proof and corrosion-resistant bio-resin coating is the same as that of Example 4.

[0042] Example 6 A solvent-resistant, rust-proof and corrosion-resistant bio-resin coating comprises the following raw materials in parts by weight: 68 parts of modified bio-based epoxy resin prepared in Example 1, 5 parts of modified graphene oxide prepared in Example 2, 14 parts of modified nano-titanium dioxide prepared in Example 3, 28 parts of curing agent 4,4'-diaminodiphenylmethane, and 20 parts of diluent acetone.

[0043] The preparation method of the above-mentioned solvent-resistant, rust-proof and corrosion-resistant bio-resin coating is the same as that of Example 4.

[0044] Comparative Example 1 A solvent-resistant, rust-proof and corrosion-resistant bio-resin coating comprises the following raw materials in parts by weight: 68 parts of the bio-based epoxy resin prepared in Example 1, 5 parts of the modified graphene oxide prepared in Example 2, 14 parts of the modified nano-titanium dioxide prepared in Example 3, 28 parts of a curing agent 4,4'-diaminodiphenylmethane, and 20 parts of a diluent acetone.

[0045] The preparation method of the above-mentioned solvent-resistant, rust-proof and corrosion-resistant bio-resin coating is the same as that of Example 4.

[0046] Comparative Example 2 A solvent-resistant, rust-proof and corrosion-resistant bio-resin coating comprises the following raw materials in parts by weight: 68 parts of modified bio-based epoxy resin prepared in Example 1, 5 parts of graphene oxide, 14 parts of modified nano-titanium dioxide prepared in Example 3, 28 parts of curing agent 4,4'-diaminodiphenylmethane, and 20 parts of diluent acetone.

[0047] The preparation method of the above-mentioned solvent-resistant, rust-proof and corrosion-resistant bio-resin coating is the same as that of Example 4.

[0048] Comparative Example 3: A solvent-resistant, rust-proof and corrosion-resistant bio-resin coating, comprising the following raw materials in parts by weight: 68 parts of the modified bio-based epoxy resin prepared in Example 1, 5 parts of the modified graphene oxide prepared in Example 2, 14 parts of nano-titanium dioxide, 28 parts of curing agent 4,4'-diaminodiphenylmethane, and 20 parts of diluent acetone.

[0049] The preparation method of the above-mentioned solvent-resistant, rust-proof and corrosion-resistant bio-resin coating is the same as that of Example 4.

[0050] Performance Testing

[0051] The bio-resin coatings prepared in Examples 4-6 and Comparative Examples 1-3 were uniformly coated on the surface of tinplate, placed in an oven at 120°C for drying and curing, and after forming a coating film, each group of experimental samples that met the test specifications were made and the following performance tests were carried out: the adhesion was determined by the cross-hatch method according to GB / T 9286-2021; the water contact angle test was carried out using a PZ-200SD contact angle tester; the pencil hardness was determined according to GB / T 6739-2022; the medium resistance was tested according to GB / T 9274-1988, the acid resistance was 10% sulfuric acid solution, the alkali resistance was 10% sodium hydroxide solution, and the salt water resistance was 5% sodium chloride solution. The end time was when the paint film began to bubble, rust or severely discolor, and slight discoloration was allowed; according to GB / T 23989-2009, the coating was reciprocatedly wiped with absorbent cotton soaked in a solvent, and the solvent resistance of the coating was evaluated with wrinkling and cracking of the film as corrosion signs, and the data results were shown in Table 1.

[0052] Table 1 Test results of sample performance

[0053]

[0054]

[0055] As can be seen from the data in Table 1, the coatings prepared in Examples 4-6 of the present invention have strong adhesion, high pencil hardness, good corrosion resistance, solvent resistance and flame retardant effect, and the water contact angle is greater than 150°, with a super hydrophobic surface. Wherein the bio-based epoxy resin is not modified in Comparative Example 1, and the measured adhesion, water contact angle, pencil hardness and corrosion resistance are lower than those in Examples 4-6, because no epoxidized polysiloxane component is added, and the graphene oxide is not modified in Comparative Example 2, and the measured water contact angle, pencil hardness and corrosion resistance are slightly worse than those in Examples 4-6, and the flame retardant performance is significantly reduced compared with Examples 4-6, because no flame retardant modifier is grafted on the surface of graphene oxide, and the nano-titanium dioxide is not modified in Comparative Example 3, and the measured water contact angle, pencil hardness and corrosion resistance are lower than those in Examples 4-6, indicating that the introduction of fluorine-containing groups can improve the corrosion resistance of the coating to a certain extent, and the pencil hardness is reduced due to the agglomeration phenomenon of nano-titanium dioxide.

[0056] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0057] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A solvent-resistant, rust-proof and corrosion-resistant bioresin coating, characterized in that: The invention comprises the following raw materials in parts by weight: 50 to 70 parts of modified bio-based epoxy resin, 2 to 5 parts of modified graphene oxide, 10 to 15 parts of modified nano titanium dioxide, 20 to 30 parts of curing agent, and 10 to 20 parts of diluent; The modified bio-based epoxy resin is made of an epoxidized polysiloxane-modified bio-based epoxy resin formed by self-polymerization of γ-glycidyloxypropyltrimethoxysilane; the modified nano-titanium dioxide is made by grafting fluorine-containing groups with nano-titanium dioxide; The modified graphene oxide is prepared by grafting a flame retardant modifier on the surface of graphene oxide, wherein the flame retardant modifier is prepared by a substitution reaction between 3-amino-1,2,4-triazole and hexachlorocyclotriphosphazene to prepare a flame retardant intermediate, and then terephthalaldehyde is used as a bridging agent to graft the flame retardant intermediate and γ-aminopropyltriethoxysilane, and further an addition reaction is carried out with DOPO to prepare the modified graphene oxide.

2. The solvent-resistant, anti-rust and anti-corrosion bio-resin coating according to claim 1, characterized in that: The curing agent is a mixture of one or more of triethylenetetramine, 4,4'-diaminodiphenylmethane and meta-xylylenediamine; the diluent is a mixture of one or more of toluene, xylene, acetone and butanone.

3. The solvent-resistant, rust-proof and corrosion-resistant bio-resin coating according to claim 1, characterized in that: The preparation method of the modified bio-based epoxy resin comprises the following steps: A. Dissolve vanillin and tyramine in anhydrous ethanol, and reflux at 55-70° C. for 4-5 hours. After the reaction is completed, filter and dry to prepare component 1. B. Component 1 and tetrabutylammonium bromide are dissolved in epichlorohydrin, and refluxed at 75-85°C for 4-6 hours, then cooled to 45-60°C, and sodium hydroxide solution is added dropwise to continue the reaction for 2-4 hours. After the reaction is completed, the solid is filtered out, and then dilute with dichloromethane, and washed with distilled water. The organic solution obtained after separation is subjected to rotary evaporation and reduced pressure distillation to remove the solvent, and a bio-based epoxy resin is prepared; C. Dissolve γ-glycidyloxypropyltrimethoxysilane in a mixed solution of ethanol and deionized water, and continue stirring for 15 to 30 minutes. Then add hydrochloric acid and continue stirring and reacting for 20 to 24 hours. After the reaction is completed, rotary evaporate to obtain epoxidized polysiloxane. Add bio-based epoxy resin to the epoxidized polysiloxane, place at 55 to 70° C. and stir for 5 to 8 hours to prepare modified bio-based epoxy resin.

4. The solvent-resistant, anti-rust and anti-corrosion bio-resin coating according to claim 1, characterized in that: The preparation method of the modified graphene oxide comprises the following steps: (1) Hexachlorocyclotriphosphazene is placed in a reactor, acetonitrile is added to dissolve the mixture, the temperature is raised to 45 to 60° C., 3-amino-1,2,4-triazole is added to deionized water to dissolve the mixture, and the mixture is added to the reactor, the mixture is stirred and mixed evenly, and then solid sodium hydroxide is added to the reactor, and the mixture is condensed and refluxed for 5 to 6 hours. After the reaction is completed, the mixture is subjected to rotary evaporation, washing, and drying to obtain a flame retardant intermediate. (2) taking the flame retardant intermediate and γ-aminopropyltriethoxysilane into a reactor, adding ethanol solvent to ultrasonically disperse them uniformly, taking terephthalaldehyde and adding ethanol to dissolve it, and then adding it into the reactor, placing it at 55-65° C. for reflux reaction for 4-7 hours, then taking DOPO and adding ethanol to dissolve it, and then adding it into the reactor, heating it to 75-85° C., and continuing the reaction for 5-7 hours. After the reaction is completed, filtering, washing, and drying, a flame retardant modifier is prepared; (3) Ultrasonic dispersion of graphene oxide in anhydrous ethanol, adding a flame retardant modifier, stirring the mixture at 100 to 125° C. in a nitrogen atmosphere for 8 to 12 hours, and filtering, washing, and drying the mixture after the reaction is completed to obtain modified graphene oxide.

5. The solvent-resistant, rust-proof and corrosion-resistant bio-resin coating according to claim 4, characterized in that: In the step (1), the molar ratio of hexachlorocyclotriphosphazene to 3-amino-1,2,4-triazole is 1:6-6.

5.

6. The solvent-resistant, anti-rust and anti-corrosion bio-resin coating according to claim 4, characterized in that: In the step (2), the molar ratio of the flame retardant intermediate, γ-aminopropyltriethoxysilane, terephthalaldehyde and DOPO is 1:6-6.3:6-6.3:12-12.

5.

7. The solvent-resistant, rust-proof and corrosion-resistant bio-resin coating according to claim 4, characterized in that: In the step (3), the mass ratio of graphene oxide to flame retardant modifier is 1:0.5-1.

8. The solvent-resistant, rust-proof and corrosion-resistant bio-resin coating according to claim 1, characterized in that: The preparation method of modified nano titanium dioxide comprises the following steps: taking 1H, 1H, 2H, 2H-perfluorodecyltrimethoxysilane, anhydrous ethanol and deionized water in a reactor, stirring and mixing for 0.5 to 1 hour, then adding nano titanium dioxide, and continuing to stir for 1 to 1.5 hours to prepare modified nano titanium dioxide.

9. The method for preparing the solvent-resistant, rust-proof and corrosion-resistant bio-resin coating according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: weighing raw materials in parts by weight, mixing modified bio-based epoxy resin and diluent evenly, then adding modified graphene oxide, modified nano titanium dioxide and curing agent and stirring evenly to prepare solvent-resistant, anti-rust and anti-corrosion bio-resin coating.

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