Ionically based polyesters and methods for their synthesis, anti-fog coatings comprising the same and applications thereof

Abstract

The present application belongs to the technical field of coating, aiming at the demand of raw material green environmental protection of current anti-fog coating, and the requirement of environmental protection and simplicity of coating production and coating process, an ionic biological based polyester and its synthesis method, anti-fog coating and its application are provided, the polyester synthesis method comprises the following steps: taking itaconic acid dimethyl ester, aliphatic diacid dimethyl ester, aliphatic diol, tetrabutyl titanate and p-cresol into a reaction container to obtain a polyester containing carbon-carbon double bond, and obtain proline choline ionic liquid, the two are mixed and reacted in methanol to obtain ionic biological based polyester, and the ionic biological based polyester is mixed with a photoinitiator and a solvent to prepare an anti-fog coating. The present application only needs one coating and ultraviolet curing, which improves the construction efficiency and reduces the energy consumption and time cost. At the same time, the coating obtained by the process has excellent optical performance and persistent anti-fog characteristics, high light transmittance, and can long-term maintain the visual effect of clear and transparent substrate material.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coatings, and particularly relates to an ionic bio-based polyester and a synthesis method thereof, an anti-fog coating containing the polyester and application thereof. BACKGROUND

[0002] Hydrophilic anti-fog coatings can avoid water vapor condensing into droplets on the surface of transparent materials due to temperature differences, thereby preventing white fog and ultimately ensuring that the base material maintains good light transmission, thus having important applications in the fields of construction, transportation and agriculture.

[0003] Patent ZL202010505684.6 discloses a hydrophilic polysiloxane copolymer and its preparation method and application, a wear-resistant self-lubricating anti-fog coating and a preparation method. The polymer can provide the base material with good anti-fog performance. However, this technical route still faces significant bottlenecks: the raw materials and solvents such as dimethylbenzene and n-hexane required in the coating preparation process are mostly of petrochemical origin, which is not only unsustainable in terms of resources, but also has high volatile organic compound (VOC) emissions and certain potential toxicity to the environment and safety in use. In recent years, with the increasing pressure on environmental protection, higher and more specific requirements have been put forward for the green environmental protection of the raw material source, production process and coating process of coatings, so the development trend of hydrophilic anti-fog coatings is: how to make the raw materials more environmentally friendly; how to use bio-based materials to make the production process avoid using and producing highly toxic substances as much as possible; and how to make the coating process as simple and environmentally friendly as possible. SUMMARY

[0004] The present application aims to meet the current demand for green and environmentally friendly raw materials for anti-fog coatings and the requirement for environmentally friendly and simple coating production and coating processes, and proposes an ionic bio-based polyester and a synthesis method thereof, an anti-fog coating containing the polyester and application thereof.

[0005] To achieve the above-mentioned application purposes, the present application provides the following technical solutions:

[0006] The synthesis method of the ionic bio-based polyester comprises the following steps:

[0007] Step 1: Weigh itaconic acid dimethyl ester, aliphatic diacid dimethyl ester, aliphatic diol, tetrabutyl titanate and p-cresol into a reaction container, heat to 140-170℃ and carry out polycondensation reaction for 8-12 hours, and then cool to obtain a polyester containing carbon-carbon double bonds. The molar ratio of itaconic acid dimethyl ester, aliphatic diacid dimethyl ester, aliphatic diol, tetrabutyl titanate and p-cresol is 1:(0-1):(1-2):(0.01-0.03):(0.01-0.06);

[0008] Step 2, proline and choline hydroxide are weighed and mixed uniformly in water, and the neutralization reaction is carried out at room temperature for 12-24 hours, and then proline choline ionic liquid is obtained by rotary evaporation and vacuum drying in sequence, the molar ratio of proline and choline hydroxide is 1:1, and the total mass fraction of proline and choline hydroxide in the aqueous solution is 20-40%;

[0009] Step 3, the polyester containing carbon-carbon double bond obtained in step 1 and the proline choline ionic liquid obtained in step 2 are mixed in methanol to carry out Michael addition reaction for 12-24 hours, and then precipitated in ethyl acetate or petroleum ether, and dried to obtain ionic bio-based polyester, the mass ratio of polyester containing carbon-carbon double bond and proline choline ionic liquid is 1: (0.3-1.0), and the total mass fraction of polyester containing carbon-carbon double bond and proline choline ionic liquid in methanol solution is 20-40%.

[0010] The aliphatic dimethyl ester in step 1 is one of 1,4-succinic acid dimethyl ester, 1,6-hexanedioic acid dimethyl ester, 1,8-octanedioic acid dimethyl ester and 1,10-decanedioic acid dimethyl ester, and the aliphatic diol is one of ethylene glycol, 1,4-butanediol, 1,6-hexanediol and 1,8-octanediol.

[0011] The application also provides an ionic bio-based polyester containing carbon-carbon double bond and amino acid ionic liquid group, which has the following formula (1) structure: (1);

[0012] In the formula, a is an integer between 10 and 50; b is an integer between 10 and 50; c is an integer between 0 and 50; * represents the repeating unit of the polymer, and the polymer chain is continuously extended based on it without termination at both ends.

[0013] R1, R2 are one of (CH2)2, (CH2)4, (CH2)6 and (CH2)8.

[0014] The application also provides an anti-fog coating, which comprises the above-mentioned ionic bio-based polyester, a photoinitiator and a solvent; the three components are respectively added in an amount of 10-20 parts of ionic bio-based polyester, 1-5 parts of photoinitiator and 75-89 parts of solvent in terms of mass fraction. The photoinitiator is one of benzophenone and isopropyl thioxanthone. The solvent is one of methanol, ethanol, n-propanol and isopropanol.

[0015] Further, the above-mentioned anti-fog coating is covered on the surface of a transparent material to form an anti-fog coating layer with a thickness of 5-20 μm. The anti-fog coating is covered on the surface of the material and cured by ultraviolet light, the wavelength of the ultraviolet light is 300-400 nm, and the cumulative energy of the ultraviolet light curing is 5000-10000 mJ / cm2.2 Finally, an anti-fog coating is formed on the surface of the material. The anti-fog coating is applied to the surface of the transparent material by spraying, doctoring or dipping.

[0016] The present application has the following advantages:

[0017] Firstly, the dimethyl dicarboxylate, dihydric alcohol, amino acid and choline used in the preparation process of the bio-based polyester anti-fog coating are all renewable raw materials of plant origin, which breaks the dependence on traditional petroleum-based raw materials and avoids toxic impurities that may be carried in petroleum chemical raw materials, ensuring the cleanliness and safety of the raw materials, and thus having good green environmental protection characteristics.

[0018] Secondly, in terms of synthesis process, step 1 is carried out in a solvent-free system, step 2 is carried out in water, and step 3 is carried out in a low-carbon alcohol, all of which are reactions carried out in mild systems, with mild reaction conditions, without the need to use toxic halogenated solvents, aliphatic hydrocarbons and aromatic hydrocarbons, and without other harsh conditions except for conventional heating in the entire process flow, which is easy on the production equipment and has high operation safety.

[0019] Thirdly, the coating only needs to be coated once and ultraviolet light cured in the coating construction process, avoiding the complicated process of traditional multi-coating, long-time thermal curing or complex post-treatment, greatly improving the construction efficiency and reducing energy consumption and time cost. At the same time, the coating obtained by this simple process has excellent optical performance and long-lasting anti-fog properties, with high light transmittance and long-term clear and transparent visual effect of the base material.

[0020] Fourthly, the ionic bio-based polyester shows wide substrate applicability, which can be firmly coated on the surface of various transparent substrates, including but not limited to glass and polyethylene terephthalate (PET) polymer film, and provides fast, uniform and long-lasting anti-fog effect. At the same time, the final degradation products in the natural environment are small molecular weight diacids and diols, which can be further decomposed by microorganisms into carbon dioxide and water, thus realizing the whole cycle environmental friendliness. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The nuclear magnetic hydrogen spectrum of the ionic bio-based polyester of Example 1 is shown in the figure;

[0022] Figure 2 The nuclear magnetic hydrogen spectrum of the ionic bio-based polyester of Example 2 is shown in the figure;

[0023] Figure 3 The infrared spectrum of the ionic bio-based polyester of Example 3 is shown in the figure;

[0024] Figure 4 The infrared spectrum of the ionic bio-based polyester of Example 4 is shown in the figure;

[0025] Figure 5 Infrared spectrum of the ionic bio-based polyester of Example 5;

[0026] Figure 6 Transmittance graph of the bio-based polyester anti-fog coating of Example 6;

[0027] Figure 7 Anti-fog performance comparison graph of uncoated and coated PET films in Example 6;

[0028] Figure 8 Anti-fog performance comparison graph of uncoated and coated glass in Example 7;

[0029] Figure 9 Anti-fog performance comparison graph of uncoated and coated glass in Example 8;

[0030] Figure 10 Anti-fog performance comparison graph of uncoated and coated PET films in Example 9. DETAILED DESCRIPTION

[0031] Example 1

[0032] The method for synthesizing the ionic bio-based polyester comprises the following steps:

[0033] Step 1, weigh dimethyl itaconate 79.0 g (0.5 mol), 1,4-butanediol 45.0 g (0.5 mol), tetrabutyl titanate 1.7 g (0.005 mol) and p-cresol 3.24 g (0.03 mol) into a reaction vessel, heat to 160°C and carry out polycondensation reaction for 12 hours, and cool to obtain a polyester containing carbon-carbon double bond, the molar ratio of dimethyl itaconate, dimethyl aliphatic diacid, aliphatic diol (1,4-butanediol in this embodiment), tetrabutyl titanate and p-cresol is 1:0:1:0.01:0.06.

[0034] Step 2, weigh proline 57.5 g (0.5 mol) and dissolve in water, then mix with 44% mass fraction choline hydroxide aqueous solution 137.5 g (0.5 mol) uniformly, react under stirring at room temperature for 24 h, then remove water by rotary evaporation at 50°C, and finally dry in a vacuum drying oven at 50°C for 3 days to obtain proline choline ionic liquid, the molar ratio of proline and choline hydroxide is 1:1, and the total mass fraction of proline and choline hydroxide in the aqueous solution is 20%.

[0035] Step 3, the carbon-carbon double bond containing polyester 10 g obtained in step 1 and the proline choline ionic liquid 5 g obtained in step 2 were mixed in methanol to carry out Michael addition reaction for 24 hours, then precipitated in ethyl acetate, and finally dried in a vacuum drying oven at 40℃ for 3 days to obtain the ionic bio-based polyester, the mass ratio of the carbon-carbon double bond containing polyester and the proline choline ionic liquid was 1:0.5, and the total mass fraction of the carbon-carbon double bond containing polyester and the proline choline ionic liquid in the methanol solution was 20%.

[0036] Example 2

[0037] The synthesis method of the ionic bio-based polyester comprises the following steps:

[0038] Step 1, dimethyl itaconate 15.8 g (0.1 mol), dimethyl 1,4-butanedioate 14.6 g (0.1 mol), 1,4-butanediol 18.0 g (0.2 mol), tetrabutyl titanate 0.68 g (0.002 mol) and p-cresol 0.32 g (0.003 mol) were weighed into a reaction container, heated to 160℃ to carry out polycondensation reaction for 24 hours, and cooled to obtain a carbon-carbon double bond containing polyester, the molar ratio of dimethyl itaconate, dimethyl aliphatic diacid (in this embodiment, dimethyl 1,4-butanedioate), aliphatic diol (in this embodiment, 1,4-butanediol), tetrabutyl titanate and p-cresol was 1:1:2:0.02:0.03.

[0039] Step 2, proline 57.5 g (0.5 mol) was dissolved in water, then mixed uniformly with 44% mass fraction of choline hydroxide aqueous solution 137.5 g (0.5 mol), stirred at room temperature for 24 hours, then water was removed by rotary evaporation at 50℃, and finally dried in a vacuum drying oven at 50℃ for 3 days to obtain a proline choline ionic liquid, the molar ratio of the proline and the choline hydroxide was 1:1, and the total mass fraction of the proline and the choline hydroxide in the aqueous solution was 40%.

[0040] Step 3, the carbon-carbon double bond containing polyester 10 g obtained in step 1 and the proline choline ionic liquid 3 g obtained in step 2 were mixed in methanol to carry out Michael addition reaction for 24 hours, then precipitated in petroleum ether, and finally dried in a vacuum drying oven at 40℃ for 3 days to obtain the ionic bio-based polyester, the mass ratio of the carbon-carbon double bond containing polyester and the proline choline ionic liquid was 1:0.3, and the total mass fraction of the carbon-carbon double bond containing polyester and the proline choline ionic liquid in the methanol solution was 40%.

[0041] Example 3

[0042] The synthesis method of the ionic bio-based polyester comprises the following steps:

[0043] Step 1, take itaconic acid dimethyl ester 79.0 g (0.5 mol), 1,4-butanediol 45.0 g (0.5 mol), tetrabutyl titanate 5.1 g (0.015 mol) and p-cresol 3.24 g (0.03 mol) into the reaction vessel, heat to 160°C and carry out the polycondensation reaction for 12 hours, and cool to obtain the polyester containing carbon-carbon double bond, the molar ratio of itaconic acid dimethyl ester, aliphatic diacid dimethyl ester, aliphatic diol (1,4-butanediol in this example), tetrabutyl titanate and p-cresol is 1:0:1:0.03:0.06.

[0044] Step 2, take proline 57.5 g (0.5 mol) and dissolve it in water, then mix with 44% mass fraction of choline hydroxide aqueous solution 137.5 g (0.5 mol) uniformly, and react for 24 h under stirring at room temperature, then remove the water by rotary evaporation at 50°C, and finally dry in a vacuum drying oven at 50°C for 3 days to obtain the proline choline ionic liquid, the molar ratio of proline and choline hydroxide is 1:1, and the total mass fraction of proline and choline hydroxide in the aqueous solution is 30%.

[0045] Step 3, mix the polyester containing carbon-carbon double bond 10 g obtained in step 1 and the proline choline ionic liquid 10 g obtained in step 2 in methanol, carry out the Michael addition reaction for 24 hours, then precipitate in petroleum ether, and finally dry in a vacuum drying oven at 40°C for 3 days to obtain the ionic bio-based polyester, the mass ratio of the polyester containing carbon-carbon double bond and the proline choline ionic liquid is 1:1, and the total mass fraction of the polyester containing carbon-carbon double bond and the proline choline ionic liquid in the methanol solution is 25%.

[0046] Example 4

[0047] The method for synthesizing the ionic bio-based polyester comprises the following steps:

[0048] Step 1, take itaconic acid dimethyl ester 79.0 g (0.5 mol), 1,4-butanediol 45.0 g (0.5 mol), tetrabutyl titanate 5.1 g (0.015 mol) and p-cresol 3.24 g (0.03 mol) into the reaction vessel, heat to 160°C and carry out the polycondensation reaction for 12 hours, and cool to obtain the polyester containing carbon-carbon double bond, the molar ratio of itaconic acid dimethyl ester, aliphatic diacid dimethyl ester, aliphatic diol (1,4-butanediol in this example), tetrabutyl titanate and p-cresol is 1:0:1:0.03:0.06.

[0049] Step 2, proline 57.5 g (0.5 mol) was dissolved in water, then mixed with choline hydroxide aqueous solution with mass fraction of 44% 137.5 g (0.5 mol) uniformly, stirred at room temperature for 24 h, then removed water by rotary evaporation at 50 ℃, finally dried in vacuum drying oven at 50 ℃ for 3 days to obtain proline choline ionic liquid, the molar ratio of proline and choline hydroxide was 1:1, the total mass fraction of proline and choline hydroxide in aqueous solution was 40%.

[0050] Step 3, the polyester containing carbon-carbon double bond 10 g obtained in step 1 and the proline choline ionic liquid 1 g obtained in step 2 were mixed in methanol to carry out Michael addition reaction for 24 hours, then precipitated in ethyl acetate, and finally dried in a vacuum drying oven at 40 ℃ for 3 days to obtain ionic bio-based polyester, the mass ratio of polyester containing carbon-carbon double bond and proline choline ionic liquid was 1:0.1, and the total mass fraction of polyester containing carbon-carbon double bond and proline choline ionic liquid in methanol solution was 30%.

[0051] Example 5

[0052] The method for synthesizing ionic bio-based polyester comprises the following steps:

[0053] Step 1, dimethyl itaconate 15.8 g (0.1 mol), 1,8-octanediol 14.6 g (0.1 mol), tetrabutyl titanate 0.68 g (0.002 mol) and p-cresol 0.64 g (0.006 mol) were put into a reaction container, heated to 160 ℃ to carry out polycondensation reaction for 24 hours, and cooled to obtain polyester containing carbon-carbon double bond, the molar ratio of dimethyl itaconate, dimethyl aliphatic diacid, aliphatic diol (1,8-octanediol in this embodiment), tetrabutyl titanate and p-cresol was 1:0:1:0.02:0.06.

[0054] Step 2, proline 57.5 g (0.5 mol) was dissolved in water, then mixed with choline hydroxide aqueous solution with mass fraction of 44% 137.5 g (0.5 mol) uniformly, stirred at room temperature for 24 h, then removed water by rotary evaporation at 50 ℃, finally dried in vacuum drying oven at 50 ℃ for 3 days to obtain proline choline ionic liquid, the molar ratio of proline and choline hydroxide was 1:1, the total mass fraction of proline and choline hydroxide in aqueous solution was 30%;

[0055] Step 3, the polyester containing carbon-carbon double bond obtained in step 1 and the proline choline ionic liquid obtained in step 2 are mixed in methanol to carry out Michael addition reaction for 24 hours, then precipitated in petroleum ether, and finally dried in a vacuum drying oven at 40°C for 3 days to obtain an ionic bio-based polyester, the mass ratio of the polyester containing carbon-carbon double bond and the proline choline ionic liquid is 1:0.5, and the total mass fraction of the polyester containing carbon-carbon double bond and the proline choline ionic liquid in the methanol solution is 30%.

[0056] In the above examples, the aliphatic dimethyl acid ester is selected from dimethyl 1,4-succinate or dimethyl 1,6-hexanedioate; one of dimethyl 1,8-octanedioate or dimethyl 1,10-decanedioate can also be selected. In the above examples, the aliphatic diol is selected from 1,4-butanediol or 1,8-octanediol; ethylene glycol or 1,6-hexanediol can also be selected.

[0057] Example 6

[0058] An anti-fog coating, comprising an ionic bio-based polyester, a photoinitiator and a solvent; the above three components are respectively put in an amount of 10 parts of ionic bio-based polyester, 1 part of benzophenone and 89 parts of methanol, and mixed uniformly at room temperature.

[0059] The above anti-fog coating is covered on the surface of the material, and is cured by ultraviolet light, the wavelength of the ultraviolet light is 300-400 nm, the cumulative energy of the ultraviolet light curing is 5000 mJ / cm 2 , and finally an anti-fog coating layer is formed on the surface of the material. The anti-fog coating is covered on the surface of the PET film by means of scraping. Figure 6 The graph of the light transmittance of the bio-based polyester anti-fog coating in Example 6 has good light transmittance in the visible light wavelength range of 380-780 nm. Figure 7 The graph of the anti-fog performance comparison of the PET film without coating and with coating in Example 6, the anti-fog effect of hot fog is tested, after the PET film is placed above the water at 60°C for 10s, a large amount of white fog appears on the PET film without coating and the text cannot be seen, while the PET film with coating can clearly observe the text under the water, proving that the coating can effectively prevent the PET film from generating hot fog.

[0060] Example 7

[0061] An anti-fog coating, comprising an ionic bio-based polyester, a photoinitiator and a solvent; the above three components are respectively put in an amount of 10 parts of ionic bio-based polyester, 1 part of benzophenone and 89 parts of methanol, and mixed uniformly at room temperature.

[0062] The above anti-fog coating is covered on the surface of the material, and is cured by ultraviolet light, the wavelength of the ultraviolet light is 300-400 nm, and the cumulative energy of the ultraviolet light curing is 8000 mJ / cm 2 Finally, an anti-fog coating layer is formed on the surface of the material. The anti-fog coating is covered on the surface of the glass by dip coating. Figure 8 The figure is a comparison of the anti-fog performance of the glass without coating and the glass with coating in Example 7. The anti-fog effect on hot fog is tested. After the glass is placed above water at 60℃ for 30s, a large number of water droplets appear on the surface of the glass without coating, making the text invisible, while the text under the water on the surface of the glass with coating can be clearly observed, proving that the coating can effectively prevent the glass surface from generating hot fog.

[0063] Example 8

[0064] An anti-fog coating, comprising an ionic bio-based polyester, a photoinitiator and a solvent; the input amounts of the above three components are respectively: 20 parts of ionic bio-based polyester, 3 parts of benzophenone, 77 parts of n-propanol, and are uniformly mixed at room temperature.

[0065] The above anti-fog coating is covered on the surface of the material, and is cured by ultraviolet light, the wavelength of the ultraviolet light is 300-400 nm, and the cumulative energy of the ultraviolet light curing is 10000 mJ / cm 2 Finally, an anti-fog coating layer is formed on the surface of the material. The anti-fog coating is covered on the surface of the glass by dip coating. Figure 9 The figure is a comparison of the anti-fog performance of the glass without coating and the glass with coating in Example 8. The anti-fog effect on cold fog is tested. After the material is frozen at-20℃ for 1h and then taken out and placed in an environment with a temperature of ≥20℃ and a humidity of ≥50%RH for 10s, white fog appears on the area without coating and the text is blurred, while the text on the area with coating can still be clearly observed, proving that the coating can effectively prevent the glass from generating cold fog.

[0066] Example 9

[0067] An anti-fog coating, comprising an ionic bio-based polyester, a photoinitiator and a solvent; the input amounts of the above three components are respectively: 20 parts of ionic bio-based polyester, 3 parts of benzophenone, 77 parts of n-propanol, and are uniformly mixed at room temperature.

[0068] The above anti-fog coating is covered on the surface of the material, and is cured by ultraviolet light, the wavelength of the ultraviolet light is 300-400 nm, and the cumulative energy of the ultraviolet light curing is 10000 mJ / cm 2 Finally, an anti-fog coating layer is formed on the surface of the material. The anti-fog coating is covered on the surface of the glass by dip coating. Figure 10The anti-fog performance of the uncoated and coated PET films in Example 9 was compared. The anti-fog effect on hot fog was tested. After the PET material was placed above water at 60°C for 10 s, a large amount of white fog appeared on the uncoated PET film and the text was not visible. The text under the water on the coated PET film could be clearly observed, proving that the coating could effectively prevent the PET film from generating hot fog.

Claims

1. A method for synthesizing an ionic bio-based polyester, characterized in that, Includes the following steps: Step 1: Weigh dimethyl itaconic acid, dimethyl aliphatic diacid, aliphatic diol, tetrabutyl titanate, and p-cresol and add them to the reaction vessel. Heat to 140-170℃ for polycondensation reaction for 8-12 hours. Cool to obtain a polyester containing carbon-carbon double bonds. The molar ratio of dimethyl itaconic acid, dimethyl aliphatic diacid, aliphatic diol, tetrabutyl titanate, and p-cresol is 1:(0-1):(1-2):(0.01-0.03):(0.01-0.06). Step 2: Weigh proline and choline hydroxide and mix them evenly in water. Allow the mixture to neutralize at room temperature for 12-24 hours. Then, obtain a proline-choline ionic liquid by rotary evaporation and vacuum drying. The molar ratio of proline to choline hydroxide is 1:1, and the total mass fraction of proline and choline hydroxide in the aqueous solution is 20-40%. Step 3: Mix the polyester containing carbon-carbon double bonds obtained in Step 1 and the proline-choline ionic liquid obtained in Step 2 in methanol and carry out a Michael addition reaction for 12-24 hours. Then, precipitate and dry to obtain an ionic bio-based polyester. The mass ratio of the polyester containing carbon-carbon double bonds to the proline-choline ionic liquid is 1:(0.3-1.0), and the total mass fraction of the polyester containing carbon-carbon double bonds and the proline-choline ionic liquid in the methanol solution is 20-40%.

2. The method for synthesizing ionic bio-based polyester according to claim 1, characterized in that, The aliphatic dimethyl diacid ester mentioned in step 1 is one of dimethyl 1,4-succinate, dimethyl 1,6-adipate, dimethyl 1,8-octanoate, and dimethyl 1,10-sebate, and the aliphatic diol is one of ethylene glycol, 1,4-butanediol, 1,6-hexanediol, and 1,8-octanediol.

3. The method for synthesizing ionic bio-based polyester according to claim 1, characterized in that, After the proline-choline ionic liquid in step 3 undergoes a Michael addition reaction, it is precipitated in ethyl acetate or petroleum ether.

4. An ionic bio-based polyester synthesized using the method of claim 1, characterized in that, The ionic bio-based polyester contains carbon-carbon double bonds and amino acid ionic liquid groups, and has the structure shown in the following formula (1); （1）； In the formula, a is an integer between 10 and 50; b is an integer between 10 and 50; c is an integer between 0 and 50; R1 is one of (CH2)4 or (CH2)8; R2 is one of (CH2)2 or (CH2)4.

5. An anti-fog coating, characterized in that, The product includes the ionic bio-based polyester as described in claim 4, and further includes a photoinitiator and a solvent; the amounts of the three components added, by mass fraction, are: 10-20 parts of ionic bio-based polyester, 1-5 parts of photoinitiator, and 75-89 parts of solvent.

6. The anti-fog coating according to claim 5, characterized in that, The photoinitiator is one of benzophenone and isopropylthioxanthrone.

7. The anti-fog coating according to claim 5, characterized in that: The solvent is one of methanol, ethanol, n-propanol, and isopropanol.

8. An application of an anti-fog coating, characterized in that, The anti-fog coating of any one of claims 5-7 is applied to the surface of a transparent material to form an anti-fog coating of 5μm-20μm.

9. The application of an anti-fog coating according to claim 8, characterized in that, The anti-fog coating is applied to the material surface and cured by ultraviolet light. The wavelength of the ultraviolet light is 300nm-400nm, and the cumulative energy of the ultraviolet curing is 5000mJ / cm². 2 -10000mJ / cm 2 Finally, an anti-fog coating is formed on the material surface.

10. The application of the anti-fog coating according to claim 9, characterized in that: The anti-fog coating is applied to the surface of a transparent material by spraying, scraping, or dipping.

Images