Super-sewage-resistant water-based ceramic coating and preparation method thereof

Abstract

The invention relates to the technical field of coatings, and discloses a super-sewage-resistant water-based ceramic coating and a preparation method thereof, and is characterized in that the super-sewage-resistant water-based ceramic coating comprises 100 parts by weight of water-based resin, 45-60 parts by weight of carboxyl-terminated fluorine-containing polysiloxane modified alumina, and 1.4-1.7 parts by weight of a curing agent; a carboxyl group at one end of the carboxyl-terminated fluorine-containing polysiloxane interacts with the nano aluminum oxide, so that the carboxyl-terminated fluorine-containing polysiloxane is uniformly dispersed in a paint film of the paint to form a micro-nano-scale convex structure, and the fluorine-containing polysiloxane contains a silicone oil molecular chain and a perfluoroalkyl chain segment with strong hydrophobicity, so that the paint film coating has very high water contact angle and super-hydrophobicity. The carboxyl at the other end of the carboxyl-terminated fluorine-containing polysiloxane can be subjected to curing reaction with the epoxy resin, so that the compatibility of the nano aluminum oxide and the epoxy resin is improved, and the mechanical property of the nano aluminum oxide is favorably improved. The super-sewage-resistant water-based porcelainized coating disclosed by the invention has better practical application in the aspects of super-hydrophobic self-cleaning, waterproof and antifouling, porcelainized coatings and the like.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, in particular to a super sewage-resistant porcelain coating and a preparation method thereof. Background Art

[0002] Superhydrophobic coatings are widely used in the fields of self-cleaning, waterproofing and antifouling. Usually, inorganic nanomaterials and low surface energy substances such as fluorine and silicon are added to the coating to give the coating superhydrophobic properties. Epoxy resin coatings have high mechanical strength and excellent anti-corrosion properties, but traditional epoxy resin coatings do not have superhydrophobic self-cleaning properties.

[0003] Nano-alumina has excellent wear resistance, mechanical strength, thermal conductivity and other properties, and is widely used in ceramic coatings, plastics, rubber and other polymer materials. The research focus is on surface modification of nano-alumina, improving its dispersibility and improving the agglomeration problem. Patent CN106995641B discloses the in-situ polymerization modification of the surface of alumina and carbon fiber with isophorone diisocyanate and hydroxyethyl methacrylate, and then filling them into epoxy resin with epoxy polyhedral silsesquioxane, which improves the thermal conductivity, insulation, thermal properties and flame retardancy of the epoxy resin coating, but the epoxy resin coating does not have super-hydrophobic self-cleaning, waterproof and anti-fouling properties. Summary of the invention

[0004] (I) Technical problems solved: The present invention solves the problem that water-based epoxy resin coatings do not have super hydrophobic properties and have poor waterproof and antifouling properties.

[0005] (II) Technical solution: A super sewage resistant coating, comprising 100 parts by weight of water-based resin, 45-60 parts by weight of carboxyl-terminated fluorinated polysiloxane modified alumina, 0.4-0.7 parts by weight of defoamer, 0.3-0.5 parts by weight of leveling agent, and 1.4-1.7 parts by weight of curing agent; the curing agent comprises 2-ethyl-4-methylimidazole. The water-based resin comprises water-based epoxy resin.

[0006] The preparation method of the super sewage resistant coating is as follows: add waterborne epoxy resin, terminal carboxyl fluorinated polysiloxane modified alumina, defoamer and leveling agent into a container, shear and disperse them in a shearing machine, and then add a curing agent to obtain the super sewage resistant coating.

[0007] The preparation method of terminal carboxyl fluorinated polysiloxane modified alumina is as follows: toluene, nano-alumina, and terminal carboxyl fluorinated polysiloxane are added into a ball mill, zirconium oxide balls are used as grinding media, the ball-to-material ratio is (5-8):1, the rotation speed is controlled at 100-400r / min, ball milling is performed for 3-5h, the zirconium oxide grinding balls are taken out, the slurry is dried to remove the toluene, and the terminal carboxyl fluorinated polysiloxane modified alumina is obtained.

[0008] Furthermore, the ratio of nano-alumina to terminal carboxyl fluorinated polysiloxane is 100 g: (10-25) g.

[0009] Further, the preparation method of the carboxyl-terminated fluorine-containing polysiloxane is as follows:

[0010] (1): Add water, sodium hydroxide, and 5-aminoisophthalic acid to a reaction vessel, stir, and then drop a tetrahydrofuran solution of perfluorooctanoyl chloride in an ice-water bath, react for 20-40 minutes, and then react at room temperature for 4-6 hours. Remove tetrahydrofuran by rotary evaporation, and drop hydrochloric acid to adjust the pH of the solution to 4-5. Precipitate, filter, wash with ice water, and dry to obtain 5-(perfluorooctanoylamide)isophthalic acid. The reaction formula is as follows:

[0011] .

[0012] (2): Add toluene, 5-(perfluorooctylamide)isophthalic acid, double-terminated hydroxypropyl polysiloxane, and p-toluenesulfonic acid to the reaction vessel, introduce nitrogen, heat to 100-110°C, condense and reflux for 18-24 hours, then add 5-(perfluorooctylamide)isophthalic acid, capping reaction for 3-5 hours, remove toluene by rotary evaporation, wash with methanol, and dry to obtain carboxyl-terminated fluorinated polysiloxane. The reaction formula is:

[0013] .

[0014] Furthermore, in (1), the ratio of sodium hydroxide, 5-aminoisophthalic acid, and perfluorooctanoyl chloride is (2.4-2.8) mol: 1 mol: (2.2-2.4) mol.

[0015] Furthermore, in (2), the ratio of 5-(perfluorooctylamide)isophthalic acid, double-terminated hydroxypropyl polysiloxane, and p-toluenesulfonic acid is (1.2-1.3) mol: 1 mol: (0.006-0.008) mol.

[0016] (III) Technical effect of the present invention: The carboxyl-terminated fluorinated polysiloxane prepared by the present invention has carboxyl groups at both ends, and one end interacts with nano-alumina, thereby realizing surface modification of nano-alumina, which is beneficial to improving the dispersibility of alumina and reducing agglomeration. At the same time, the modified nano-alumina is evenly dispersed in the coating film matrix to form a micro-nano-scale protrusion structure. The fluorinated polysiloxane contains highly hydrophobic silicone oil molecular chains and perfluoroalkyl segments, which make the coating film exhibit a very high water contact angle and super-hydrophobic properties, and has excellent anti-fouling and waterproof properties. The other end carboxyl group of the carboxyl-terminated fluorinated polysiloxane can undergo a curing reaction with the epoxy group of the epoxy resin at high temperature, thereby improving the interfacial bonding strength and compatibility between the nano-alumina and the epoxy resin, which is beneficial to improving the mechanical strength and wear resistance of the epoxy resin.

[0017] The carboxyl-terminated fluorine-containing polysiloxane of the present invention contains a flexible polysiloxane molecular chain, which can play a good toughening role after being cured with the epoxy resin, so that the epoxy resin casting body exhibits good tensile strength and elongation at break.

[0018] The present invention adds carboxyl-terminated fluorinated polysiloxane to modify alumina, and the wear resistance of the epoxy resin paint film coating is improved. After multiple friction and wear cycles, it still has a good water contact angle and super hydrophobic properties. The super sewage resistant coating of the present invention has better practical applications in super hydrophobic self-cleaning, waterproof and antifouling, and porcelainizable coatings. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0020] The waterborne epoxy resin of the present invention, Shandong Chengtai Chemical Co., Ltd., solid content 50%. Jinan Chenghao Chemical Co., Ltd.; double-terminal hydroxypropyl polysiloxane, average molecular weight 1300, Hubei Xinyuhong Biomedical Technology Co., Ltd. Nano-alumina, average particle size 20nm, Qinghe County Ruijiang Metal Materials Co., Ltd.

[0021] Embodiment 1:

[0022] (1): Add 15 mL of water, 14 mmol of sodium hydroxide, and 5 mmol of 5-aminoisophthalic acid to a reaction vessel. After stirring, add 30 mL of a tetrahydrofuran solution containing 12 mmol of perfluorooctanoyl chloride dropwise in an ice-water bath. React for 40 min, then react at room temperature for 4 h. Remove tetrahydrofuran by rotary evaporation. Add hydrochloric acid dropwise to adjust the pH of the solution to 4. Precipitate the precipitate. Filter, wash with ice water, and dry to obtain 5-(perfluorooctanoylamide)isophthalic acid.

[0023] (2): Add 60 mL of toluene, 10 mmol of 5-(perfluorooctylamide)isophthalic acid, 10 mmol of double-terminated hydroxypropyl polysiloxane, and 0.06 mmol of p-toluenesulfonic acid into a reaction vessel, introduce nitrogen, heat to 110°C, condense and reflux to react for 24 hours, then add 3 mmol of 5-(perfluorooctylamide)isophthalic acid, react for 3 hours, remove toluene by rotary evaporation, wash with methanol, and dry to obtain terminal carboxyl fluorinated polysiloxane.

[0024] (3): Add 40 mL of toluene, 20 g of nano-alumina, and 2 g of terminal carboxyl-containing fluorinated polysiloxane into a ball mill, use zirconium oxide balls as the grinding medium, the ball-to-material ratio is 5:1, the rotation speed is controlled at 400 r / min, and the ball mill is milled for 3 h. Remove the zirconium oxide grinding balls, dry the slurry to remove the toluene, and obtain terminal carboxyl-containing fluorinated polysiloxane modified alumina.

[0025] (4): Add 100 g of water-based epoxy resin, 45 g of terminal carboxyl fluorinated polysiloxane modified alumina, 0.7 g of defoamer, and 0.3 g of leveling agent into a container, shear and disperse them in a shearing machine, and then add 1.7 g of curing agent 2-ethyl-4-methylimidazole to obtain a super sewage resistant coating.

[0026] Embodiment 2:

[0027] (1): Add 10 mL of water, 12 mmol of sodium hydroxide, and 5 mmol of 5-aminoisophthalic acid to a reaction vessel. After stirring, add 20 mL of a tetrahydrofuran solution containing 11 mmol of perfluorooctanoyl chloride dropwise in an ice-water bath. React for 20 min, then react at room temperature for 6 h. Remove tetrahydrofuran by rotary evaporation. Add hydrochloric acid dropwise to adjust the pH of the solution to 5. Precipitate the precipitate. Filter, wash with ice water, and dry to obtain 5-(perfluorooctanoylamide)isophthalic acid.

[0028] (2): Add 80 mL of toluene, 10 mmol of 5-(perfluorooctylamide)isophthalic acid, 10 mmol of double-terminated hydroxypropyl polysiloxane, and 0.08 mmol of p-toluenesulfonic acid into a reaction vessel, introduce nitrogen, heat to 100°C, condense and reflux to react for 24 hours, then add 2 mmol of 5-(perfluorooctylamide)isophthalic acid, react for 5 hours, remove toluene by rotary evaporation, wash with methanol, and dry to obtain terminal carboxyl fluorinated polysiloxane.

[0029] (3): Add 70 mL of toluene, 20 g of nano-alumina, and 3.5 g of terminal carboxyl-containing fluorinated polysiloxane into a ball mill, use zirconium oxide balls as the grinding medium, the ball-to-material ratio is 8:1, the rotation speed is controlled at 300 r / min, and the ball mill is performed for 4 h. Remove the zirconium oxide grinding balls, dry the slurry to remove the toluene, and obtain terminal carboxyl-containing fluorinated polysiloxane modified alumina.

[0030] (4): Add 100 g of water-based epoxy resin, 45 g of terminal carboxyl fluorinated polysiloxane modified alumina, 0.4 g of defoamer, and 0.5 g of leveling agent into a container, shear and disperse them in a shearing machine, and then add 1.6 g of curing agent 2-ethyl-4-methylimidazole to obtain a super sewage resistant coating.

[0031] Embodiment 3:

[0032] (1): Add 80 mL of toluene, 10 mmol of 5-(perfluorooctylamide)isophthalic acid (prepared according to the method of Example 1), 10 mmol of double-terminated hydroxypropyl polysiloxane, and 0.07 mmol of p-toluenesulfonic acid into a reaction container, introduce nitrogen, heat to 100°C, condense and reflux to react for 24 hours, then add 2.6 mmol of 5-(perfluorooctylamide)isophthalic acid, react for 5 hours, remove toluene by rotary evaporation, wash with methanol, and dry to obtain terminal carboxyl fluorine-containing polysiloxane.

[0033] (2): Add 70 mL of toluene, 20 g of nano-alumina, and 5 g of terminal carboxyl-containing fluorinated polysiloxane into a ball mill, use zirconium oxide balls as the grinding medium, the ball-to-material ratio is 6:1, the speed is controlled at 100 r / min, and the ball mill is milled for 5 hours. Remove the zirconium oxide grinding balls, dry the slurry to remove the toluene, and obtain terminal carboxyl-containing fluorinated polysiloxane modified alumina.

[0034] (3): Add 100g of water-based epoxy resin, 45g of terminal carboxyl fluorinated polysiloxane modified alumina, 0.7g of defoamer, and 0.5g of leveling agent into a container, shear and disperse them in a shearing machine, and then add 1.4g of curing agent 2-ethyl-4-methylimidazole to obtain a super sewage resistant coating.

[0035] Embodiment 4:

[0036] (1): Add 100 g of waterborne epoxy resin, 52 g of terminal carboxyl fluorinated polysiloxane modified alumina (prepared in Example 2), 0.4 g of defoamer, and 0.5 g of leveling agent into a container, shear and disperse them in a shearing machine, and then add 1.6 g of curing agent 2-ethyl-4-methylimidazole to obtain a super sewage resistant coating.

[0037] Embodiment 5:

[0038] (1): Add 100 g of waterborne epoxy resin, 60 g of terminal carboxyl fluorinated polysiloxane modified alumina (prepared in Example 2), 0.4 g of defoamer, and 0.5 g of leveling agent into a container, shear and disperse them in a shearing machine, and then add 1.6 g of curing agent 2-ethyl-4-methylimidazole to obtain a super sewage resistant coating.

[0039] Comparative Example 1:

[0040] (1): Add 100g of water-based epoxy resin, 45g of nano-alumina, 0.7g of defoamer, and 0.3g of leveling agent into a container, shear and disperse them in a shearing machine, and then add 1.7g of curing agent 2-ethyl-4-methylimidazole to obtain a super sewage resistant coating.

[0041] Comparative Example 2:

[0042] (1): Add 40 mL of toluene, 20 g of nano-alumina, and 2 g of double-terminal hydroxypropyl polysiloxane into a ball mill, use zirconium oxide balls as the grinding medium, the ball-to-material ratio is 5:1, the speed is controlled at 400 r / min, and the ball mill is performed for 3 h. The zirconium oxide grinding balls are removed, and the slurry is dried to remove the toluene to obtain polysiloxane-alumina.

[0043] (2): Add 100g of water-based epoxy resin, 45g of polysiloxane-alumina, 0.7g of defoamer, and 0.3g of leveling agent into a container, shear and disperse them in a shearing machine, and then add 1.7g of curing agent 2-ethyl-4-methylimidazole to obtain a super sewage resistant coating.

[0044] Comparative Example 3:

[0045] (1): Add 60 mL of toluene, 10 mmol of isophthalic acid, 10 mmol of double-terminated hydroxypropyl polysiloxane, and 0.06 mmol of p-toluenesulfonic acid into a reaction vessel, introduce nitrogen, heat to 110°C, condense and reflux to react for 24 hours, then add 3 mmol of isophthalic acid, react for 3 hours, remove toluene by rotary evaporation, wash with methanol, and dry to obtain carboxyl-terminated polysiloxane.

[0046] (2): Add 40 mL of toluene, 20 g of nano-alumina, and 2 g of terminal carboxyl polysiloxane into a ball mill, use zirconium oxide balls as the grinding medium, the ball-to-material ratio is 5:1, the speed is controlled at 400 r / min, and the ball mill is milled for 3 hours. Remove the zirconium oxide grinding balls, dry the slurry to remove the toluene, and obtain terminal carboxyl polysiloxane modified alumina.

[0047] (3): Add 100g of water-based epoxy resin, 45g of terminal carboxyl polysiloxane modified alumina, 0.7g of defoamer, and 0.3g of leveling agent into a container, shear and disperse them in a shearing machine, and then add 1.7g of curing agent 2-ethyl-4-methylimidazole to obtain a super sewage resistant coating.

[0048] Comparative Example 4:

[0049] (1): Add 40 mL of toluene, 20 g of nano-alumina, and 2 g of 5-(perfluorooctylamide)isophthalic acid (prepared in Example 1) into a ball mill, use zirconium oxide balls as grinding media, the ball-to-material ratio is 5:1, control the rotation speed to 400 r / min, ball mill for 3 h, remove the zirconium oxide grinding balls, dry the slurry to remove toluene, and obtain fluorine-modified alumina.

[0050] (2): Add 100g of water-based epoxy resin, 45g of fluorine-modified alumina, 0.7g of defoamer, and 0.3g of leveling agent into a container, shear and disperse them in a shearing machine, and then add 1.7g of curing agent 2-ethyl-4-methylimidazole to obtain a super sewage resistant coating.

[0051] The coating was sprayed on the surface of the tinplate substrate, and cured at 80°C for 3h and 120°C for 2h to form a paint film coating. The water contact angle W0 was tested according to the national standard GB / T 30447-2013.

[0052] The paint film coating was rubbed by sandpaper friction method. 800-grit red sandpaper was pasted on the bottom of a 500g weight, and then placed on the surface of the paint film coating. The weight was pulled at a constant speed of 10cm / s. One back-and-forth pull was recorded as one wear cycle. After 50 wear cycles, the water contact angle W1 was tested again.

[0053] Pour the coating into the mold, cure it at 80°C for 4 hours and then at 120°C for 4 hours to make a casting sample, and test the tensile properties according to the national standard GB / T 2567-2021.

[0054] Table 1

[0055] <![CDATA[Water contact angle W0 (°)]]> <![CDATA[Water contact angle W1 (°)]]> Tensile strength (MPa) Elongation at break (%) Example 1 150.7 150.1 37.7 7.80 Example 2 152.6 152.2 42.5 9.16 Example 3 152.0 150.9 40.8 9.73 Example 4 153.8 153.3 47.6 14.58 Example 5 153.1 151.9 44.0 15.29 Comparative Example 1 132.2 126.4 33.5 3.72 Comparative Example 2 134.5 129.6 32.4 3.77 Comparative Example 3 141.6 140.7 37.9 7.54 Comparative Example 4 138.7 136.0 35.0 4.41

[0056] As can be seen from the table above, in Comparative Example 1, nano-alumina is added to the epoxy resin coating, which has not been surface modified, has poor dispersibility, poor compatibility with epoxy resin, is easily agglomerated, does not form a good micro-nano protrusion structure, has a small water contact angle, does not show super-hydrophobic properties, and has poor waterproof and antifouling properties. In addition, the tensile strength and elongation at break of the coating are low.

[0057] The carboxyl-terminated fluorinated polysiloxane of Examples 1-5 contains carboxyl groups at both ends, one end of which interacts with nano-alumina to achieve surface modification of the nano-alumina, which is beneficial to improving the dispersibility of alumina and reducing agglomeration. The carboxyl group at the other end can undergo a curing reaction with the epoxy group of the epoxy resin at high temperature, thereby improving the interfacial bonding strength and compatibility between the nano-alumina and the epoxy resin, which is beneficial to improving the mechanical strength and wear resistance of the epoxy resin. In addition, the carboxyl-terminated fluorinated polysiloxane contains flexible polysiloxane molecular chains, which can play a good toughening role after curing with the epoxy resin, so that the epoxy resin casting exhibits good tensile strength and elongation at break. At the same time, the modified nano-alumina is evenly dispersed in the paint film matrix to form a micro-nano-scale protrusion structure. The fluorinated polysiloxane contains strongly hydrophobic silicone oil molecular chains and perfluoroalkyl segments, which makes the paint film coating exhibit a very high water contact angle and super hydrophobic properties, and has excellent anti-fouling and waterproof properties. In addition, by adding terminal carboxyl fluorinated polysiloxane-modified alumina, the wear resistance of the epoxy resin paint film coating is improved. After multiple friction and wear cycles, it still has a good water contact angle and super hydrophobic properties.

[0058] The double-terminal hydroxypropyl polysiloxane of Comparative Example 2 does not contain a carboxyl group, has a low interaction force with the surface of nano-alumina, and has a poor modification effect. In addition, it does not contain a carboxyl group, and is difficult to undergo a curing reaction with the epoxy resin. The nano-alumina has poor dispersibility, is easy to agglomerate, does not form a micro-nano-scale protrusion structure, has a small water contact angle, does not exhibit a superhydrophobic system, and has poor interfacial bonding strength and compatibility with the epoxy resin, and the tensile strength and elongation at break of the casting are low.

[0059] In Comparative Example 3, isophthalic acid and double-terminated hydroxypropyl polysiloxane are reacted to obtain a carboxyl-terminated polysiloxane that does not contain a perfluoroalkyl long chain and has low hydrophobicity, resulting in a low water contact angle of the paint film and poor superhydrophobicity.

[0060] Comparative Example 4 uses 5-(perfluorooctylamide)isophthalic acid to modify the surface of nano-alumina, which does not contain hydrophobic and flexible polysiloxane segments. The water contact angle of the paint film is low, the superhydrophobic performance is poor, and the toughening effect is poor. The elongation at break of the casting is low.

[0061] The selection and description of the above embodiments are intended to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various modified embodiments suitable for specific use considerations.

Claims

1. A super sewage resistant porcelain coating, characterized in that: The super sewage resistant coating comprises 100 parts by weight of water-based resin, 45-60 parts by weight of carboxyl-terminated fluorinated polysiloxane-modified alumina, 0.4-0.7 parts by weight of defoamer, 0.3-0.5 parts by weight of leveling agent, and 1.4-1.7 parts by weight of curing agent; The preparation method of the terminal carboxyl fluorinated polysiloxane modified alumina comprises the following steps: adding toluene, nano-alumina and terminal carboxyl fluorinated polysiloxane into a ball mill, ball milling, drying the slurry to remove the toluene, and obtaining the terminal carboxyl fluorinated polysiloxane modified alumina.

2. The super sewage resistant porcelain coating according to claim 1, characterized in that: The curing agent includes 2-ethyl-4-methylimidazole.

3. The super sewage resistant porcelain coating according to claim 1, characterized in that, The ratio of the nano-alumina to the terminal carboxyl fluorine-containing polysiloxane is 100 g: (10-25) g.

4. The super sewage resistant porcelain coating according to claim 1, characterized in that: The rotation speed during ball milling is 100-400 r / min, and the ball milling time is 3-5 h.

5. The super sewage resistant porcelain coating according to claim 1, characterized in that: During the ball milling, zirconia balls are used as grinding media, and the ball-to-material ratio is (5-8):

1.

6. The super sewage resistant porcelain coating according to claim 3, characterized in that: The preparation method of the carboxyl-terminated fluorine-containing polysiloxane is as follows: (1): Add water, sodium hydroxide and 5-aminoisophthalic acid to a reaction vessel, stir, then dropwise add a tetrahydrofuran solution of perfluorooctanoyl chloride in an ice-water bath, react for 20-40 minutes, then react at room temperature for 4-6 hours, remove tetrahydrofuran by rotary evaporation, dropwise add hydrochloric acid to precipitate, filter, wash with ice water, and dry to obtain 5-(perfluorooctanoylamide)isophthalic acid; (2): Add toluene, 5-(perfluorooctylamide)isophthalic acid, double-terminated hydroxypropyl polysiloxane, and p-toluenesulfonic acid into a reaction vessel, introduce nitrogen, heat to 100-110°C, condense and reflux to react for 18-24 hours, then add 5-(perfluorooctylamide)isophthalic acid, react for 3-5 hours, remove toluene by rotary evaporation, wash with methanol, and dry to obtain a carboxyl-terminated fluorinated polysiloxane.

7. The super sewage resistant porcelain coating according to claim 6, characterized in that: The ratio of sodium hydroxide, 5-aminoisophthalic acid and perfluorooctanoyl chloride in (1) is (2.4-2.8) mol: 1 mol: (2.2-2.4) mol.

8. The super sewage resistant porcelain coating according to claim 6, characterized in that: In the step (1), hydrochloric acid is added dropwise to adjust the pH of the solution to 4-5.

9. The super sewage resistant porcelain coating according to claim 6, characterized in that: The ratio of 5-(perfluorooctylamide)isophthalic acid, double-terminated hydroxypropyl polysiloxane and p-toluenesulfonic acid in (2) is (1.2-1.3) mol:1 mol:(0.006-0.008) mol.

10. A method for preparing a super sewage resistant porcelain coating according to any one of claims 1 to 9, characterized in that: The preparation method comprises the following steps: adding water-based resin, terminal carboxyl fluorinated polysiloxane modified alumina, defoamer and leveling agent into a container, shearing and dispersing the mixture in a shearing machine, and then adding a curing agent to obtain a super sewage-resistant porcelain coating.