A waterproof, antifouling and antibacterial copolymer protective layer and preparation method thereof

Abstract

The present invention discloses a waterproof, antifouling and antibacterial copolymer protective layer and a preparation method thereof, and relates to the technical field of antifouling coatings. At least the following steps are included: octamethylcyclotetrasiloxane and aminopropyltrimethylsilane are mixed and reacted to obtain a side chain amino-modified polysiloxane polymer; the side chain amino-modified polysiloxane polymer is mixed with an epoxy resin containing a quaternary ammonium salt, and after magnetic stirring, ethyl orthosilicate and dibutyltin diacetate are added, and vacuum degassing is performed to obtain a waterproof, antifouling and antibacterial copolymer coating; the waterproof, antifouling and antibacterial copolymer coating is wiped or sprayed on a dry and clean substrate surface, and after drying and curing, a waterproof, antifouling and antibacterial copolymer protective layer is obtained. The waterproof, antifouling and antibacterial copolymer protective layer prepared in the present application covers the surface of the substrate, is odorless and non-toxic, anti-aging, waterproof and oil-proof, antibacterial and mildew-proof, antifouling and anti-graffiti, and has excellent antifouling and self-cleaning functions.

Description

Technical Field

[0001] The invention relates to the technical field of antifouling coatings, and in particular to a waterproof, antifouling and antibacterial copolymer protective layer and a preparation method thereof. Background Art

[0002] Transparent and strong omniphobic coatings have a significant repellent effect on the water-based and oily pollutants that we need to clean, so they have broad application prospects. Smooth polymer-based antifouling coatings are low surface tension components covalently grafted into traditional coating systems. This smooth surface prepared without the need to create rough micro / nano structures can eliminate the shortcomings of other antifouling coatings such as low optical transparency and low wear resistance. At the same time, the coating has the advantages of high optical transparency, controllable thickness, stable antifouling effect and applicability to multiple types of substrates, making it have a wide range of application value.

[0003] Polysiloxane (organic silicon) is a polymer whose molecular chain segments are alternately connected by silicon atoms and oxygen atoms, and other organic groups are connected to the silicon atoms. The main chain of polysiloxane is a repeated Si-O-Si structure. Organic groups such as methyl, methoxy, ethyl, ethoxy, phenyl, etc. can be covalently connected to the silicon atoms of the main chain. Therefore, the main chain of polysiloxane is highly flexible and exhibits certain conformational mobility. Due to the unique chemical structure of polysiloxane, it is endowed with low surface energy, low elastic modulus, low roughness, high and low temperature resistance, aging resistance, water resistance, moisture resistance, corrosion resistance and other excellent properties, so it is widely used in the field of functional coatings and the modification of functional coatings.

[0004] However, various harmful microorganisms are very easy to grow and breed on the surface of polysiloxane materials, which seriously threatens human health. In the field of marine antifouling, polysiloxane coating can remove the stain only under dynamic conditions or by using mechanical force to achieve the effect of stain release, and the antifouling effect under static conditions is poor. Due to the low surface energy of polysiloxane materials, they are only suitable for coating on the surface of highly reactive substrates and cannot be applied on surfaces with low reactive activity, such as metals, glass, etc., which limits their scope of application. In addition, polysiloxane materials have low mechanical strength and are easily destroyed when subjected to mechanical external forces, shortening their service life. Therefore, polysiloxane materials are modified to improve their waterproof, antifouling and antibacterial capabilities, which is of great significance to the application of polysiloxane materials in the fields of biomedicine and marine antifouling. Summary of the invention

[0005] The purpose of the present invention is to provide a waterproof, antifouling and antibacterial copolymer protective layer and a preparation method thereof, so as to solve the following technical problems:

[0006] The existing polysiloxane antifouling coating has the problems of poor antifouling and antibacterial effect, weak substrate adhesion and poor mechanical properties.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] A method for preparing a waterproof, antifouling and antibacterial copolymer protective layer comprises at least the following steps:

[0009] Octamethylcyclotetrasiloxane and aminopropyltrimethoxysilane are mixed and heated to 80-120° C. under a nitrogen protection environment, reacted for 40-60 minutes under mechanical stirring, and vacuumed for dehydration. After the reaction system shows a "transparent-turbid-transparent" phenomenon, the vacuum is continued for 2-3 hours, and then tetramethylammonium hydroxide is added, reacted at 100-130° C. for 3-5 hours, and the temperature is rapidly raised to 155-160° C. and maintained for 30-40 minutes to obtain a side chain amino-modified polysiloxane polymer;

[0010] The side chain amino-modified polysiloxane polymer is mixed with an epoxy resin containing a quaternary ammonium salt, and after being evenly stirred by magnetic force, ethyl orthosilicate and dibutyltin diacetate are added, and the mixture is placed in a vacuum dryer for vacuum degassing at room temperature to obtain a waterproof, antifouling and antibacterial copolymer coating;

[0011] The waterproof, antifouling and antibacterial copolymer coating is rubbed or sprayed on a dry and clean substrate surface, and after drying and curing, a waterproof, antifouling and antibacterial copolymer protective layer is obtained.

[0012] As a further embodiment of the present invention, the molar ratio of the amino group of the side chain amino-modified polysiloxane polymer to the epoxy group of the epoxy resin containing the quaternary ammonium salt is 1:1.

[0013] As a further embodiment of the present invention, the mass ratio of the octamethylcyclotetrasiloxane to the aminopropyltrimethoxysilane is 1:1-5, and the mass ratio of the tetraethyl orthosilicate to the side chain amino-modified polysiloxane polymer is 1:10-20.

[0014] As a further solution of the present invention: the substrate includes at least one of leather, plastic, wood, stainless steel, glass, paint or stone, and the waterproof, antifouling and antibacterial copolymer coating has a room temperature drying time of 6-10 minutes and a curing time of 20-24 hours after being coated on the surface of the substrate.

[0015] As a further embodiment of the present invention: the preparation method of the epoxy resin containing quaternary ammonium salt comprises the following steps:

[0016] The chitosan quaternary ammonium salt is dissolved in a 1,4-dioxane aqueous solution, the temperature is raised to 40-85°C, epichlorohydrin is slowly added dropwise, and after the addition is completed, the temperature is kept for 30-240 minutes, the temperature of the reaction system is lowered to 10-40°C, sodium hydroxide or potassium hydroxide solution is added, the reaction is carried out for 30-120 minutes, dialyzed and dried to obtain the epoxy resin containing the quaternary ammonium salt.

[0017] As a further solution of the present invention: the mass ratio of the chitosan quaternary ammonium salt to the epichlorohydrin is 1-10:1.

[0018] A waterproof, antifouling and antibacterial copolymer protective layer is prepared by any one of the above-mentioned methods for preparing a waterproof, antifouling and antibacterial copolymer protective layer.

[0019] Beneficial effects of the present invention:

[0020] The waterproof, antifouling and antibacterial copolymer coating prepared by the present application is odorless, non-toxic, anti-aging, waterproof and oil-proof, antibacterial and mildew-proof, antifouling and anti-graffiti, and has excellent antifouling and self-cleaning functions. The obtained waterproof, antifouling and antibacterial copolymer coating also has good high and low temperature resistance, and the use temperature range is -40℃-300℃. It does not wrinkle, crack or fall off, and the performance is maintained well. It can be applied to various product surfaces that require waterproof, antifouling, anti-graffiti and anti-aging. The present application uses side chain amino-modified polysiloxane polymers and epoxy resins containing quaternary ammonium salts for cross-linking. There are multiple active hydrogens in the chemical structure of the synthesized side chain amino-modified polysiloxane polymer, especially the active hydrogen on the side chain amino group, which can react with the epoxy group to form a polymer cross-linking network with a ladder structure. The synthetic copolymer coating not only retains the excellent performance of the polysiloxane itself with low surface energy and good fouling desorption, but also has the advantages of high strength, high adhesion, low shrinkage and good processing performance of epoxy resin.

[0021] The epoxy resin containing quaternary ammonium salt in the present application contains epoxy groups with high chemical reactivity. Due to the tension of the three-membered ring of the epoxy group, its properties are relatively active and can react with other substances containing active hydrogen (such as amino, carboxyl, carboxyl, etc.) to form a covalent bond. In the present application, it can react with the active hydrogen on the side chain amino group of the side chain amino-modified polysiloxane polymer, thereby introducing the chitosan quaternary ammonium salt molecule into the polysiloxane polymer to make it a part of the material, avoiding the defects caused by physical blending. The introduced quaternary ammonium salt functional groups are evenly distributed in the material, improving the antibacterial performance of the copolymer coating and enhancing the function of desorption of fouling. At the same time, the epoxy resin containing quaternary ammonium salt contains two or more epoxy groups, so it can produce a cross-linking effect. The cross-linking modification effect can be controlled by regulating the number of epoxy groups in the molecule to meet the needs of different applications.

[0022] In the present application, the cross-linking agent tetraethyl orthosilicate has also been added, the organic group in the tetraethyl orthosilicate molecule can react chemically with the matrix, form a firm chemical bond, thereby increase the adhesion and durability of coating, simple to the substrate surface treatment requirements such as metal, cement, substrate surface treatment is clean, the surface is free of dust accumulation, oil stains, rust and other attachments. Tetraethyl orthosilicate can also form a cross-linked network structure with the matrix, improves the hardness and wear resistance of coating. In addition, after containing quaternary ammonium salt epoxy resin and material reaction, still retain the main structure of chitosan quaternary ammonium salt, chitosan is introduced into the copolymer not only to improve the viscoelasticity of the copolymer protective layer, increase the hardness, adhesion and impact strength of the protective layer, also improve the acid resistance, alkali resistance and solvent resistance of the protective layer. DETAILED DESCRIPTION

[0023] The following will be described clearly and completely in conjunction with 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.

[0024] Example 1 The preparation method of epoxy resin containing quaternary ammonium salt comprises the following steps:

[0025] Mix 80 g of water and 20 g of 1,4-dioxane to obtain 100 g of a mixed solvent, dissolve 5 g of chitosan quaternary ammonium salt in 100 g of the mixed solvent, and heat to 60° C., slowly drop 1.5 g of epichlorohydrin, and after the dropwise addition is complete, heat for 60 min, lower the temperature of the reaction system to 25° C., add sodium hydroxide solution, and react for 60 min;

[0026] The above reactants are placed in a dialysis bag with a molecular weight cutoff of 500Da, immersed in distilled water, dialyzed for 120 minutes, discarded the distilled water, then dialyzed in distilled water for 240 minutes, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, took out the dialyzed reactants, and dried them by freeze drying to obtain an epoxy resin containing quaternary ammonium salt.

[0027] The preparation method of the waterproof, antifouling and antibacterial copolymer protective layer comprises the following steps:

[0028] Take 100ml of octamethylcyclotetrasiloxane and 200ml of aminopropyltrimethoxysilane, put them into a four-necked round-bottom flask equipped with a tetrafluoroethylene stirrer, a thermometer and a high-purity nitrogen protection device, heat the mixture in the reaction flask to 95°C under a nitrogen protection environment, react for 40 minutes under mechanical stirring, then heat the reaction system to 110°C, turn on the vacuum pump and control the pump meter reading at 0.07 MPa, vacuum dehydrate, and continue to react for 2h after the reaction system shows the phenomenon of "transparent-turbid-transparent", stop vacuuming and add 1mL of tetramethylammonium hydroxide to the reaction system, react at 125°C for 4h, quickly heat to 155°C and keep for 30min to remove tetramethylammonium hydroxide in the reaction system. Finally, take the method of reduced pressure distillation, distill the reaction product at 115°C under reduced pressure to remove unreacted low-boiling substances, and obtain a side chain amino-modified polysiloxane polymer;

[0029] The side chain amino-modified polysiloxane polymer and the epoxy resin containing quaternary ammonium salt are mixed in a molar ratio of amino group to epoxy group of 1:1, and after magnetic stirring, 0.25g of ethyl orthosilicate and 0.01g of dibutyltin diacetate are added, and the mixture is placed in a vacuum dryer for vacuum degassing at room temperature to obtain a waterproof, antifouling and antibacterial copolymer coating;

[0030] Apply 10 ml of the above waterproof, antifouling and antibacterial copolymer coating on the surface of a dry and clean glass substrate, and wipe the area to 10 m 2 The surface is dried at room temperature for 6 minutes and completely cured for 24 hours to obtain a waterproof, antifouling and antibacterial copolymer protective layer.

[0031] Example 2 The preparation method of epoxy resin containing quaternary ammonium salt comprises the following steps:

[0032] Mix 80 g of water and 20 g of 1,4-dioxane to obtain 100 g of a mixed solvent, dissolve 5 g of chitosan quaternary ammonium salt in 100 g of the mixed solvent, and heat to 60° C., slowly drop 3 g of epichlorohydrin, and after the dropwise addition is complete, keep the temperature for 60 min, lower the temperature of the reaction system to 25° C., add sodium hydroxide solution, and react for 60 min;

[0033] The above reactants are placed in a dialysis bag with a molecular weight cutoff of 500Da, immersed in distilled water, dialyzed for 120 minutes, discarded the distilled water, then dialyzed in distilled water for 240 minutes, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, took out the dialyzed reactants, and dried them by freeze drying to obtain an epoxy resin containing quaternary ammonium salt.

[0034] In the step of preparing the waterproof, antifouling and antibacterial copolymer protective layer, the epoxy resin containing quaternary ammonium salt in Example 1 is replaced by the epoxy resin containing quaternary ammonium salt prepared in this example according to the required epoxy group content, and the other components and preparation method are the same as those in Example 1.

[0035] Example 3 The components and preparation method of the epoxy resin containing quaternary ammonium salt are the same as those in Example 1.

[0036] The preparation method of the waterproof, antifouling and antibacterial copolymer protective layer comprises the following steps:

[0037] Take 100ml of octamethylcyclotetrasiloxane and 400ml of aminopropyltrimethoxysilane, put them into a four-necked round-bottom flask equipped with a tetrafluoroethylene stirrer, a thermometer and a high-purity nitrogen protection device, heat the mixture in the reaction flask to 95°C under a nitrogen protection environment, react for 40 minutes under mechanical stirring, then heat the reaction system to 110°C, turn on the vacuum pump and control the pump meter reading at 0.07 MPa, vacuum dehydrate, and continue to react for 2h after the reaction system shows the phenomenon of "transparent-turbid-transparent", stop vacuuming and add 2mL of tetramethylammonium hydroxide to the reaction system, react at 125°C for 4h, quickly heat to 155°C and keep for 30min to remove tetramethylammonium hydroxide in the reaction system. Finally, adopt the method of reduced pressure distillation, and distill the reaction product at 115°C under reduced pressure to remove unreacted low-boiling substances to obtain a side chain amino-modified polysiloxane polymer;

[0038] The side chain amino-modified polysiloxane polymer and the epoxy resin containing quaternary ammonium salt are mixed in a molar ratio of amino group to epoxy group of 1:1, and after magnetic stirring, 0.25g of ethyl orthosilicate and 0.01g of dibutyltin diacetate are added, and the mixture is placed in a vacuum dryer for vacuum degassing at room temperature to obtain a waterproof, antifouling and antibacterial copolymer coating;

[0039] Apply 10 ml of the above waterproof, antifouling and antibacterial copolymer coating on the surface of a dry and clean glass substrate, and wipe the area to 10 m 2 The surface is dried at room temperature for 6 minutes and completely cured for 24 hours to obtain a waterproof, antifouling and antibacterial copolymer protective layer.

[0040] Comparative Example 1 The preparation method of the epoxy resin containing quaternary ammonium salt comprises the following steps:

[0041] Mix 80 g of water and 20 g of 1,4-dioxane to obtain 100 g of a mixed solvent, dissolve 5 g of chitosan in 100 g of the mixed solvent, and heat to 60°C, slowly drop 1.5 g of epichlorohydrin, and after the dropwise addition, keep the temperature for 60 min, lower the temperature of the reaction system to 25°C, add sodium hydroxide solution, and react for 60 min;

[0042] The above reactants were loaded into a dialysis bag with a molecular weight cutoff of 500Da, immersed in distilled water, dialyzed for 120 minutes, discarded the distilled water, then dialyzed in distilled water for 240 minutes, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, taken out the dialyzed reactants, and dried them by freeze drying to obtain chitosan-modified epoxy resin.

[0043] In the step of preparing the waterproof, antifouling and antibacterial copolymer protective layer, the epoxy resin containing quaternary ammonium salt in Example 1 is replaced with the chitosan-modified epoxy resin prepared in this comparative example according to the required epoxy group content, and the other components and preparation method are the same as those in Example 1.

[0044] Comparative Example 2 The preparation method of the epoxy resin containing quaternary ammonium salt comprises the following steps:

[0045] Mix 80 g of water and 20 g of 1,4-dioxane to obtain 100 g of a mixed solvent, dissolve 5 g of chitosan quaternary ammonium salt in 100 g of the mixed solvent, and heat to 60° C., slowly drop 1.5 g of chloropropylcyclotrisiloxane, and after the dropwise addition is complete, heat for 60 min, lower the temperature of the reaction system to 25° C., add sodium hydroxide solution, and react for 60 min;

[0046] The above reactants are placed in a dialysis bag with a molecular weight cutoff of 500Da, immersed in distilled water, dialyzed for 120 minutes, discarded the distilled water, then dialyzed in distilled water for 240 minutes, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, dialyzed in distilled water for 24 hours, discarded the distilled water, taken out the dialyzed reactants, and dried them by freeze drying to obtain a silane resin containing a quaternary ammonium salt.

[0047] In the step of preparing the waterproof, antifouling and antibacterial copolymer protective layer, the epoxy resin containing quaternary ammonium salt in Example 1 is replaced by the silane resin containing quaternary ammonium salt prepared in this comparative example according to the required content of epoxy groups, and the other components and preparation method are the same as those in Example 1.

[0048] Comparative Example 3 The components and preparation method of the epoxy resin containing quaternary ammonium salt are the same as those in Example 1.

[0049] The preparation method of the waterproof, antifouling and antibacterial copolymer protective layer comprises the following steps:

[0050] Take 100ml of octamethylcyclotetrasiloxane and 200ml of aminopropyltrimethoxysilane, put them into a four-necked round-bottom flask equipped with a tetrafluoroethylene stirrer, a thermometer and a high-purity nitrogen protection device, heat the mixture in the reaction flask to 95°C under a nitrogen protection environment, react for 40 minutes under mechanical stirring, then heat the reaction system to 110°C, turn on the vacuum pump and control the pump meter reading at 0.07 MPa, vacuum dehydrate, and continue to react for 2h after the reaction system shows the phenomenon of "transparent-turbid-transparent", stop vacuuming and add 1mL of tetramethylammonium hydroxide to the reaction system, react at 125°C for 4h, quickly heat to 155°C and keep for 30min to remove tetramethylammonium hydroxide in the reaction system. Finally, take the method of reduced pressure distillation, distill the reaction product at 115°C under reduced pressure to remove unreacted low-boiling substances, and obtain a side chain amino-modified polysiloxane polymer;

[0051] The side chain amino-modified polysiloxane polymer and the epoxy resin containing quaternary ammonium salt are uniformly mixed in a molar ratio of amino group to epoxy group of 1:1, and placed in a vacuum dryer for vacuum degassing at room temperature to obtain a waterproof, antifouling and antibacterial copolymer coating;

[0052] Apply 10 ml of the above waterproof, antifouling and antibacterial copolymer coating on the surface of a dry and clean glass substrate, and wipe the area to 10 m 2 The surface is dried at room temperature for 6 minutes and completely cured for 24 hours to obtain a waterproof, antifouling and antibacterial copolymer protective layer.

[0053] Performance Testing

[0054] The copolymer protective layers obtained in Examples 1-3 and Comparative Examples 1-3 were tested for various properties, and the test results are shown in the following table;

[0055]

[0056] As can be seen from the above table, the waterproof, antifouling and antibacterial copolymer coating prepared in Examples 1-3 of the present application is coated on a substrate, and will produce a grafting effect with the surface molecules of the substrate material while infiltrating various substrates, thereby forming a graft copolymer protective layer, improving the physical, chemical and mechanical properties of the substrate material, and improving the heat resistance, weather resistance, wear resistance, water resistance, stain resistance, acid, alkali and salt resistance and other properties. In Comparative Example 1, no quaternary ammonium salt group was introduced, and the antibacterial properties of the obtained coating were significantly reduced. In Comparative Example 2, no epoxy group was introduced, and the mechanical properties of the obtained coating were reduced. In Comparative Example 3, no cross-linking agent ethyl orthosilicate was introduced, and the adhesion and hardness of the obtained coating were reduced. It shows that the waterproof, antifouling and antibacterial copolymer protective layer obtained by the preparation method of the present application improves the mechanical properties, antifouling and antibacterial properties and adhesion on the substrate of the polysiloxane copolymer coating.

[0057] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A method for preparing a waterproof, antifouling and antibacterial copolymer protective layer, characterized in that: At least the following steps are included: Octamethylcyclotetrasiloxane and aminopropyltrimethoxysilane are mixed and heated to 80-120°C under a nitrogen atmosphere, reacted for 40-60 minutes under mechanical stirring, and vacuumed for dehydration. After the reaction system shows a "transparent-turbid-transparent" phenomenon, the reaction is continued for 2-3 hours, then vacuuming is stopped and tetramethylammonium hydroxide is added, reacted at 100-130°C for 3-5 hours, and the temperature is rapidly raised to 155-160°C and maintained for 30-40 minutes to obtain a side chain amino-modified polysiloxane polymer; The side chain amino-modified polysiloxane polymer is mixed with an epoxy resin containing a quaternary ammonium salt, and after being evenly stirred by magnetic force, ethyl orthosilicate and dibutyltin diacetate are added, and the mixture is placed in a vacuum dryer for vacuum degassing at room temperature to obtain a waterproof, antifouling and antibacterial copolymer coating; Applying or spraying the waterproof, antifouling and antibacterial copolymer coating on a dry and clean substrate surface, and obtaining a waterproof, antifouling and antibacterial copolymer protective layer after drying and curing; Wherein, the molar ratio of the amino group of the side chain amino-modified polysiloxane polymer to the epoxy group of the epoxy resin containing the quaternary ammonium salt is 1:1; The mass ratio of the octamethylcyclotetrasiloxane to the aminopropyltrimethoxysilane is 1:1-5, and the mass ratio of the tetraethyl orthosilicate to the side chain amino-modified polysiloxane polymer is 1:10-20.

2. The method for preparing a waterproof, antifouling and antibacterial copolymer protective layer according to claim 1, characterized in that: The substrate comprises at least one of leather, plastic, wood, stainless steel, glass, paint or stone. After the waterproof, antifouling and antibacterial copolymer coating is coated on the surface of the substrate, the room temperature drying time is 6-10 minutes and the curing time is 20-24 hours.

3. The method for preparing a waterproof, antifouling and antibacterial copolymer protective layer according to claim 1, characterized in that: The preparation method of the epoxy resin containing quaternary ammonium salt comprises the following steps: The chitosan quaternary ammonium salt is dissolved in a 1,4-dioxane aqueous solution, the temperature is raised to 40-85°C, epichlorohydrin is slowly added dropwise, and after the addition is completed, the temperature is kept for 30-240 minutes, the temperature of the reaction system is lowered to 10-40°C, sodium hydroxide solution or potassium hydroxide solution is added, the reaction is carried out for 30-120 minutes, dialyzed and dried to obtain the epoxy resin containing the quaternary ammonium salt.

4. The method for preparing a waterproof, antifouling and antibacterial copolymer protective layer according to claim 3, characterized in that: The mass ratio of the chitosan quaternary ammonium salt to the epichlorohydrin is 1-10:

1.

5. A waterproof, antifouling and antibacterial copolymer protective layer, characterized in that: Prepared by the preparation method described in any one of claims 1 to 4.

Images