Environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating, preparation method and application thereof

Abstract

The present invention discloses an environmentally adaptable, water-based, durable short-chain fluorinated water- and oil-repellent coating, a preparation method, and its application. The main component of the coating is a multi-component copolymer obtained by random copolymerization of two or more comonomers, wherein the comonomer selection includes a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer, and at least one of an acrylic functional monomer. The coating can not only impart excellent water- and oil-repellent properties to the substrate without affecting the original appearance and performance of the substrate, but also solves the problem of poor hydrophobic and oleophobic stability of short-chain fluorinated alkyl compounds in the prior art, and meets the requirements for stable water- and oil-repellent, green and environmentally friendly, and long-lasting weather resistance of the material.

Description

Technical Field

[0001] The present invention belongs to the technical field of water- and oil-repellent coatings, and relates to an environmentally adaptable, water-based, durable short-chain fluorinated water- and oil-repellent coating, a preparation method and applications thereof, and in particular to a short-chain fluorinated water- and oil-repellent coating whose main component is a multi-polymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer and an acrylic functional monomer. Background Art

[0002] Fluorinated water and oil repellent coatings are based on perfluoroalkyl or polyfluoroalkyl compounds, where perfluoroalkyl or polyfluoroalkyl compounds refer to compounds in which all or part of the hydrogen atoms on the carbon chain of the molecule are replaced by fluorine atoms to form a fluorocarbon chain structure. Since the CF bond in the fluoroalkyl chain has a low surface free energy and critical surface tension, especially long-chain perfluoroalkyl compounds (C n F 2n+1 , n≥8) are enriched on the surface and can most effectively reduce the surface free energy. Therefore, it is widely used in water- and oil-repellent treatment of clothing decoration and industrial textiles, paper and leather, giving the substrate excellent water- and oil-repellent properties.

[0003] However, studies have shown that long-chain perfluoroalkyl compounds will release perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) after degradation in the environment. These compounds are biotoxic, bioaccumulative, and environmentally mobile, posing a threat to both humans and the environment. They have been banned in the international community and on the market. The bioaccumulation of perfluoroalkyl compounds depends largely on the length of the fluorocarbon chain. Short-chain fluoroalkyl compounds containing six or fewer fluorocarbon atoms are less toxic and bioaccumulative than long-chain perfluoroalkyl compounds. Therefore, short-chain fluoroalkyl compounds (-C n F 2n+1 , n≤6) have become ideal materials to replace long-chain perfluoroalkyl compounds. However, the side chains of short-chain fluoroalkyl compounds cannot crystallize and often form an amorphous structure, which has stronger chain segment mobility. When in contact with water or other polar liquids, the fluorinated side groups rearrange, resulting in poor dynamic hydrophobicity and oleophobicity.

[0004] In view of the above problems, there is an urgent need to develop an environmentally friendly short-chain fluorine-containing water- and oil-repellent coating with excellent water- and oil-repellent properties. Summary of the Invention

[0005] In order to solve the problems in the above-mentioned prior art, the present invention provides an environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating, a preparation method and its application. The coating is a multipolymer obtained by random copolymerization of short-chain fluorinated acrylate monomers, crystallizable acrylate monomers and acrylic functional monomers as main components. It can not only give the substrate excellent water- and oil-repellent properties without affecting the original appearance and performance of the substrate, but also solves the problem of poor hydrophobic and oleophobic stability of short-chain fluorinated alkyl compounds in the prior art, and meets the requirements of stable water- and oil-repellent, green and environmentally friendly, and long-lasting weather resistance of the material.

[0006] To achieve the above objectives, the present invention is implemented by adopting a technical solution consisting of the following technical measures.

[0007] On the one hand, the present invention provides an environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating, the main component of which is a multi-polymer obtained by random copolymerization of two or more comonomers, and the comonomers are selected to include short-chain fluorinated acrylate monomers, and at least one of crystallizable acrylate monomers and acrylic functional monomers.

[0008] In one technical solution, the multi-component copolymer is a binary copolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer and a crystallizable acrylate monomer;

[0009] Or it is a terpolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer and an acrylic functional monomer.

[0010] When the multi-component copolymer is a binary copolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer and a crystallizable acrylate monomer, the chemical structure of the binary copolymer is as follows:

[0011]

[0012] Wherein R1=-H, -CH3;

[0013] R2=-N(CH3)SO2C4F9,-N(CH3)SO2C6F 13 、-NHCOOCH2CH2C4F9、

[0014] -NHCOOCH2CH2C6F 13 , -C6H4COOCH2CH2C4F9, -C6H4COOCH2CH2C6F 13 、-CH2CH2C6F 12 、-CH2CH2(CF2) n CF3, n = 2, 3, 4, 5;

[0015] R3=-(CH2) n CH3, n≥9;

[0016] X and Y are the number of repeating units, and both are not greater than 100.

[0017] When the multi-polymer is a terpolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer, and an acrylic functional monomer, the chemical structure of the obtained terpolymer is as follows:

[0018]

[0019] Wherein R1=-H, -CH3;

[0020] R2=-N(CH3)SO2C4F9,-N(CH3)SO2C6F 13 、-NHCOOCH2CH2C4F9、

[0021] -NHCOOCH2CH2C6F 13 , -C6H4COOCH2CH2C4F9, -C6H4COOCH2CH2C6F 13 、-CH2CH2C6F 12 、-CH2CH2(CF2) n CF3, n = 2, 3, 4, 5;

[0022] R3=-(CH2) n CH3, n≥9;

[0023] R4=-CH2CH2OH, -CH2CH2CH(O)CH, -CH2CH2COOH;

[0024] X, Y, and Z are the numbers of repeating units, and are all no greater than 100.

[0025] In this article, the short-chain fluorinated acrylate monomer is a fluorocarbon group in the side chain and the fluorocarbon group satisfies -C n F 2n+1 (n≤6) acrylate monomer.

[0026] In one of the technical solutions, the short-chain fluorinated acrylate monomer is selected from at least one of tridecafluorooctyl acrylate, 2-(perfluorohexyl)ethyl methacrylate, 1H,1H,7H-perfluoroheptyl acrylate, 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl methacrylate, 1H,1H,2H,2H-nonafluorohexyl acrylate, 1H,1H,2H,2H-nonafluorohexyl methacrylate, 2,2,3,3,4,4,4-heptafluorobutyl acrylate, 2,2,3,3,4,4,4-heptafluorobutyl methacrylate, (N-methylperfluorobutylsulfonamido)ethyl acrylate, (N-methylperfluorobutylsulfonamido)ethyl methacrylate, (N-methylperfluorohexylsulfonamido)ethyl acrylate, (N-methylperfluorohexylsulfonamido)ethyl methacrylate, and perfluorohexylethyl parahydroxybenzoate.

[0027] Herein, the crystallizable acrylate monomer is a saturated alkyl chain in the side chain and the saturated alkyl chain satisfies -C n H 2n+1 (n≥10) acrylate monomer.

[0028] In one technical solution, the crystallizable acrylate monomer is selected from at least one of octadecyl acrylate, octadecyl methacrylate, hexacosyl acrylate, hexacosyl methacrylate, tetracosyl acrylate, tetracosyl methacrylate, behenyl acrylate, behenyl methacrylate, octadecyl acrylate, octadecyl methacrylate, hexadecyl acrylate, hexadecyl methacrylate, tetradecyl acrylate, tetradecyl methacrylate, dodecyl acrylate, dodecyl methacrylate, octadecyl acrylate, octadecyl methacrylate, hexadecyl acrylate, hexadecyl methacrylate, tetradecyl acrylate, tetradecyl methacrylate, dodecyl acrylate, dodecyl methacrylate, isodecyl acrylate, and isodecyl methacrylate.

[0029] Herein, the acrylic functional monomer is an acrylate monomer having a side chain containing a -CH(O)CH, -OH or -COOH functional group.

[0030] In one technical solution, the acrylic functional monomer is selected from at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, glycidyl methacrylate, glycidyl acrylate, acrylic acid, and methacrylic acid.

[0031] The inventive point of the present invention is that, through a large number of exploratory experiments, it was found that the multi-polymer obtained by random copolymerization of short-chain fluorinated acrylate monomers with crystallizable acrylate monomers and / or acrylic functional monomers can effectively solve the problem of poor hydrophobic and oleophobic stability of short-chain fluorinated alkyl compounds. This will provide a new way to better utilize short-chain fluorinated alkyl compounds to prepare water- and oil-repellent coatings.

[0032] However, it is important to note that during the above-mentioned experiments, we also found that the selection and ratio of comonomers can have a very significant impact on the water and oil repellency of the final coating, and this impact is not uniform. In particular, monomers that perform well in binary copolymers do not necessarily perform better in ternary copolymers, and may even show a decrease in performance. On the other hand, monomers that perform poorly in binary copolymers can show a significant improvement in performance in ternary copolymers. The reasons for this phenomenon are currently unknown.

[0033] Based on the above findings and through empirical summary, the following optimal technical solutions are obtained:

[0034] When the multi-component copolymer is a binary copolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer and a crystallizable acrylate monomer, in one of the more preferred technical solutions, the short-chain fluorinated acrylate monomer is selected as tridecafluorooctyl acrylate, and the crystallizable acrylate monomer is selected as dodecyl acrylate. The water- and oil-repellent properties of the prepared coating are the best overall performance. However, in the experimental group of the entire comparative experiment, the coating prepared based on the binary copolymer still has the disadvantages of poor adhesion, poor water resistance, low glass transition temperature, and easy softening and deformation of the coating when used at room temperature.

[0035] When the multipolymer is a terpolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer and an acrylic functional monomer, in one of the more preferred technical solutions, when the crystallizable acrylate monomer is selected as octadecyl acrylate or octadecyl methacrylate, it is surprisingly found that the water- and oil-repellent properties of the coating prepared therefrom are better, and have higher hydrophobic and oleophobic stability, and are greatly improved compared to prior art literature records, which illustrates that the terpolymer has a very significant advantage over the binary copolymer. The specific selection of the acrylic functional monomer has less impact on the water- and oil-repellent properties of the coating prepared therefrom, but at the same time, the ratio of the short-chain fluorinated acrylate monomer to the crystallizable acrylate monomer also has a more significant impact on the water- and oil-repellent properties of the coating prepared therefrom.

[0036] Based on the above comparative experimental results, in one of the more preferred technical solutions, when the multipolymer is a ternary copolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer and an acrylic functional monomer, the ternary copolymer is obtained by random copolymerization of 15 to 20 parts of a short-chain fluorinated acrylate monomer, 5 to 10 parts of a crystallizable acrylate monomer and 5 to 10 parts of an acrylic functional monomer, in parts by mass.

[0037] In this article, those skilled in the art can know based on common knowledge that the raw material components of the coating generally also include surfactants, initiators and solvents. Those skilled in the art can select and add surfactants, initiators and solvents that are conventionally added to coatings in the prior art in this field.

[0038] In one technical solution, the surfactant comprises an anionic surfactant and a nonionic surfactant in a ratio of 4:1 to 1:1. The anionic surfactant is sodium lauryl sulfonate or / and sodium lauryl sulfate, and the nonionic surfactant is at least one of OP-10, TX-10, and NP-10. The surfactant is added in an amount of 3 to 8 wt% of the total weight of the comonomer.

[0039] In one technical solution, the initiator is selected from at least one of ammonium persulfate, potassium persulfate and sodium persulfate, and the amount of the initiator added is 1 to 3 wt% of the total weight of the comonomer.

[0040] In one technical solution, the solvent can be selected as a conventional water solvent, and the amount of the solvent added is 60-75 wt% of the total mass of the coating.

[0041] On the other hand, the present invention also provides a method for preparing the above-mentioned environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating, which mainly comprises the following steps:

[0042] (1) adding a surfactant to a solvent, stirring and dispersing the mixture for 0.5 to 1 hour, then adding a comonomer and stirring the mixture to obtain a comonomer dispersion;

[0043] (2) placing the comonomer dispersion obtained in step (1) in a homogenizer and homogenizing and dispersing at 8000-10000 rpm for 15-30 minutes to obtain a pre-emulsion;

[0044] (3) dissolving the initiator in a solvent to prepare an initiator solution;

[0045] (4) Under inert gas protection, the pre-emulsion obtained in step (2) and the initiator obtained in step (3) are dissolved and added into a reaction vessel, and the mixture is stirred under condensation reflux at 75-80° C. for 5-7 h, and the pH of the product is adjusted to neutral to prepare an environmentally adaptable water-based durable short-chain fluorine-containing water- and oil-repellent coating.

[0046] The above-mentioned environmentally adaptable water-based durable short-chain fluorine-containing water- and oil-repellent coating can be used as a coating for water- and oil-repellent treatment of surfaces such as textiles, paper, glass, and wood.

[0047] Herein, the stirring, dissolving, condensing and reflux all follow conventional principles in chemical processes, and those skilled in the art can perform specific operations based on common knowledge.

[0048] The present invention has the following beneficial effects:

[0049] (1) The present invention provides an environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating, the main component of which is a water-based short-chain fluorinated acrylate polymer (-C n F 2n+1 , n≤6), introducing a crystallizable monomer into the fluorinated monomer can be used to replace the long-chain perfluoroalkyl compound (-C n F 2n+1 , n≥8), avoids the problems of difficult degradation and bioaccumulation of long fluorocarbon chains, has little impact on the environment, meets environmental protection requirements, and improves the water and oil repellency of the coating, while also overcoming the poor water and oil repellency of short-chain fluorinated acrylic polymers.

[0050] (2) The present invention provides an environmentally adaptable, water-based, durable, short-chain fluorine-containing water- and oil-repellent coating having good thermal stability. The coating can be widely used as a water- and oil-repellent treatment agent for surface treatment of textiles (e.g., cotton fabrics), paper, rubber, and polymer materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a comparison of the water contact angle hysteresis of the copolymer film formed on a glass surface after coating the sample prepared in Example 1. PFA, prepared by homopolymerizing tridecafluorooctyl acrylate using conventional methods, served as a control sample, while FC18 corresponded to the sample prepared in Example 1.

[0052] Figure 2 The following are the actual display pictures of the water repellency and water contact angle test pictures of the sample prepared in Example 1 coated on the surfaces of cotton fabric, PET, linen, glass and wood.

[0053] Figure 3 The static water contact angle and oil contact angle (n-hexadecane) bar graphs of the sample prepared in Example 1 coated on the surfaces of cotton fabric, PET, linen, glass and wood are shown.

[0054] Figure 4 This is a physical display of the water and oil repellency of the sample prepared in Example 1 applied to cotton fabric against cola, milk, coffee, edible oil, acid (pH=1) and silicone oil.

[0055] Figure 5 The sample prepared in Example 1 was coated on cotton fabric, and the water contact angle change diagram and surface morphology photograph of the fabric were obtained after 100 washing cycles.

[0056] Figure 6 This is a water contact angle test diagram of the sample prepared in Example 3 coated on a glass surface.

[0057] Figure 7 This is a water contact angle test diagram of the sample prepared in Example 5 coated on a glass surface. DETAILED DESCRIPTION

[0058] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than for limiting the claims of the invention. Those skilled in the art can refer to the contents of this article and appropriately improve the process parameters for implementation. It is particularly important to point out that all similar replacements and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention. Although it is believed that those of ordinary skill in the art fully understand the following terms, the following definitions are still stated to help illustrate the subject matter disclosed by the present invention.

[0059] On the one hand, the present invention provides an environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating, the main component of which is a multi-polymer obtained by random copolymerization of two or more comonomers, and the comonomers are selected to include short-chain fluorinated acrylate monomers, and at least one of crystallizable acrylate monomers and acrylic functional monomers.

[0060] In one embodiment, the multi-component copolymer is a binary copolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer and a crystallizable acrylate monomer;

[0061] Or it is a terpolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer and an acrylic functional monomer.

[0062] In one embodiment, when the multi-component copolymer is a binary copolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer and a crystallizable acrylate monomer, the chemical structure of the binary copolymer is as follows:

[0063]

[0064] Wherein R1=-H, -CH3;

[0065] R2=-N(CH3)SO2C4F9,-N(CH3)SO2C6F 13 、-NHCOOCH2CH2C4F9、

[0066] -NHCOOCH2CH2C6F 13 , -C6H4COOCH2CH2C4F9, -C6H4COOCH2CH2C6F 13 、-CH2CH2C6F 12 、-CH2CH2(CF2) n CF3, n = 2, 3, 4, 5;

[0067] R3=-(CH2) n CH3, n≥9;

[0068] X and Y are the number of repeating units, and both are not greater than 100.

[0069] In one embodiment, when the multi-polymer is a terpolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer, and an acrylic functional monomer, the chemical structure of the obtained terpolymer is as follows:

[0070]

[0071] Wherein R1=-H, -CH3;

[0072] R2=-N(CH3)SO2C4F9,-N(CH3)SO2C6F 13 、-NHCOOCH2CH2C4F9、

[0073] -NHCOOCH2CH2C6F 13 , -C6H4COOCH2CH2C4F9, -C6H4COOCH2CH2C6F 13 、-CH2CH2C6F 12 、-CH2CH2(CF2) n CF3, n = 2, 3, 4, 5;

[0074] R3=-(CH2) nCH3, n≥9;

[0075] R4=-CH2CH2OH, -CH2CH2CH(O)CH, -CH2CH2COOH;

[0076] X, Y, and Z are the numbers of repeating units, and are all no greater than 100.

[0077] In this article, the short-chain fluorinated acrylate monomer is a fluorocarbon group in the side chain and the fluorocarbon group satisfies -C n F 2n+1 (n≤6) acrylate monomer.

[0078] In one embodiment, the short-chain fluorinated acrylate monomer is selected from at least one of tridecafluorooctyl acrylate, 2-(perfluorohexyl)ethyl methacrylate, 1H,1H,7H-perfluoroheptyl acrylate, 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl methacrylate, 1H,1H,2H,2H-nonafluorohexyl acrylate, 1H,1H,2H,2H-nonafluorohexyl methacrylate, 2,2,3,3,4,4,4-heptafluorobutyl acrylate, 2,2,3,3,4,4,4-heptafluorobutyl methacrylate, (N-methylperfluorobutylsulfonamido)ethyl acrylate, (N-methylperfluorobutylsulfonamido)ethyl methacrylate, (N-methylperfluorohexylsulfonamido)ethyl acrylate, (N-methylperfluorohexylsulfonamido)ethyl methacrylate, and perfluorohexylethyl p-hydroxybenzoate.

[0079] Herein, the crystallizable acrylate monomer is a saturated alkyl chain in the side chain and the saturated alkyl chain satisfies -C n H2 n+1 (n≥10) acrylate monomer.

[0080] In one embodiment, the crystallizable acrylate monomer is selected from at least one of octadecyl acrylate, octadecyl methacrylate, hexacosyl acrylate, hexacosyl methacrylate, tetracosyl acrylate, tetracosyl methacrylate, behenyl acrylate, behenyl methacrylate, octadecyl acrylate, octadecyl methacrylate, hexadecyl acrylate, hexadecyl methacrylate, tetradecyl acrylate, tetradecyl methacrylate, lauryl acrylate, lauryl methacrylate, isodecyl acrylate, and isodecyl methacrylate.

[0081] Herein, the acrylic functional monomer is an acrylate monomer having a side chain containing a -CH(O)CH, -OH or -COOH functional group.

[0082] In one embodiment, the acrylic functional monomer is selected from at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, glycidyl methacrylate, glycidyl acrylate, acrylic acid, and methacrylic acid.

[0083] The inventive point of the present invention is that, through a large number of exploratory experiments, it was found that the multi-polymer obtained by random copolymerization of short-chain fluorinated acrylate monomers with crystallizable acrylate monomers and / or acrylic functional monomers can effectively solve the problem of poor hydrophobic and oleophobic stability of short-chain fluorinated alkyl compounds, which will provide a new way to better utilize short-chain fluorinated alkyl compounds to prepare coatings.

[0084] However, it is important to note that during the above-mentioned experiments, we also found that the selection and ratio of comonomers can have a very significant impact on the water and oil repellency of the final coating, and this impact is not uniform. In particular, monomers that perform well in binary copolymers do not necessarily perform better in ternary copolymers, and may even show a decrease in performance. On the other hand, monomers that perform poorly in binary copolymers can show a significant improvement in performance in ternary copolymers. The reasons for this phenomenon are currently unknown.

[0085] Based on the above findings and through empirical summary, the following optimal technical solutions are obtained:

[0086] When the multi-component copolymer is a binary copolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer and a crystallizable acrylate monomer, in one of the more preferred embodiments, the short-chain fluorinated acrylate monomer is selected as tridecafluorooctyl acrylate, and the crystallizable acrylate monomer is selected as dodecyl acrylate. The water- and oil-repellent properties of the prepared coating are the best overall performance. However, in the experimental group of the entire comparative experiment, the coating prepared based on the binary copolymer still has the disadvantages of poor adhesion, poor water resistance, low glass transition temperature, and easy softening and deformation of the coating when used at room temperature.

[0087] When the multipolymer is a terpolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer and an acrylic functional monomer, in one of the more preferred embodiments, when the crystallizable acrylate monomer is selected as octadecyl acrylate or octadecyl methacrylate, it is surprisingly found that the water- and oil-repellent properties of the coating prepared are better, and have higher hydrophobic and oleophobic stability, and are greatly improved compared to prior art document records, which illustrates that the terpolymer has a very significant advantage over binary copolymers. The specific selection of the acrylic functional monomer has less impact on the water- and oil-repellent properties of the coating prepared, but at the same time, the ratio of the short-chain fluorinated acrylate monomer to the crystallizable acrylate monomer also has a significant impact on the water- and oil-repellent properties of the coating prepared.

[0088] Based on the above comparative experimental results, in one of the more preferred embodiments, when the multipolymer is a ternary copolymer obtained by random copolymerization of a short-chain fluorinated acrylate monomer, a crystallizable acrylate monomer and an acrylic functional monomer, it is obtained by random copolymerization of 15 to 20 parts of a short-chain fluorinated acrylate monomer, 5 to 10 parts of a crystallizable acrylate monomer and 5 to 10 parts of an acrylic functional monomer, in parts by mass.

[0089] In this article, those skilled in the art can know based on common knowledge that the raw material components of the coating generally also include surfactants, initiators and solvents. Those skilled in the art can select and add surfactants, initiators and solvents that are conventionally added to coatings in the prior art in this field.

[0090] In one embodiment, the surfactant comprises an anionic surfactant and a nonionic surfactant in a ratio of 4:1 to 1:1, for example, 4:1, 3:1, 2:1, 1:1, or any range or value therebetween; the anionic surfactant is sodium lauryl sulfonate and / or sodium lauryl sulfate, and the nonionic surfactant is at least one of OP-10, TX-10, and NP-10. The surfactant is added in an amount of 3 to 8 wt% of the total weight of the comonomer, for example, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, or any range or value therebetween.

[0091] In one embodiment, the initiator comprises at least one of ammonium persulfate, potassium persulfate, and sodium persulfate. The initiator is added in an amount of 1 to 3 wt% of the total weight of the comonomer, such as 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, or any range or value therebetween.

[0092] In one embodiment, the solvent may be a conventional aqueous solvent. The amount of the solvent added is 60-75 wt% of the total weight of the coating, for example, 60 wt%, 61 wt%, 62 wt%, 63 wt%, 64 wt%, 65 wt%, 66 wt%, 67 wt%, 68 wt%, 69 wt%, 70 wt%, 71 wt%, 72 wt%, 73 wt%, 74 wt%, 75 wt% or any range or point value therebetween.

[0093] On the other hand, the present invention also provides a method for preparing the above-mentioned environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating, which mainly comprises the following steps:

[0094] (1) adding a surfactant to a solvent, stirring and dispersing the mixture for 0.5 to 1 hour, and then adding a comonomer and stirring the mixture to obtain a comonomer dispersion;

[0095] (2) placing the comonomer dispersion obtained in step (1) in a homogenizer and homogenizing and dispersing at 8000-10000 rpm for 15-30 minutes to obtain a pre-emulsion;

[0096] (3) dissolving the initiator in a solvent to prepare an initiator solution;

[0097] (4) Under inert gas protection, the pre-emulsion obtained in step (2) and the initiator obtained in step (3) are dissolved and added into a reaction vessel, and the mixture is stirred under condensation reflux at 75-80° C. for 5-7 h, and the pH of the product is adjusted to neutral to prepare an environmentally adaptable water-based durable short-chain fluorine-containing water- and oil-repellent coating.

[0098] The above-mentioned environmentally adaptable water-based durable short-chain fluorine-containing water- and oil-repellent coating can be used as a coating for water- and oil-repellent treatment of surfaces such as textiles, paper, glass, and wood.

[0099] In one embodiment, the stirring and dispersing in step (1) is for 0.5 to 1 h, the purpose of which is to properly emulsify it, for example, 0.5 h, 0.6 h, 0.7 h, 0.8 h, 0.9 h, 1 h or any range or point value therebetween.

[0100] In one embodiment, the homogenizing dispersion in step (2) is carried out at 8000-10000 rpm for 15-30 min, for example, at 8000 rpm, 8500 rpm, 9000 rpm, 9500 rpm or 10000 rpm, and the processing time can be 15 min, 20 min, 25 min or 30 min.

[0101] In one embodiment, the step (4) is carried out under condensation reflux stirring and reaction at 75-80°C for 5-7h, for example, under the temperature conditions of 75°C, 76°C, 77°C, 78°C, 79°C, 80°C or any range or point value therebetween, and the reaction is carried out under condensation reflux stirring and reaction for 5h, 5.5h, 6h, 6.5h, 7h or any range or point value therebetween.

[0102] Herein, the stirring, dissolving, condensing and reflux all follow conventional principles in chemical processes, and those skilled in the art can perform specific operations based on common knowledge.

[0103] The present invention will be further explained in detail below with reference to the examples. However, it will be appreciated by those skilled in the art that these examples are provided for illustrative purposes only and are not intended to limit the present invention.

[0104] Example

[0105] The embodiments of the present application will be described in detail below in conjunction with the examples, but it will be appreciated by those skilled in the art that the following examples are merely illustrative of the present application and should not be considered as limiting the scope of the present application. In the examples, if no specific conditions are indicated, the conditions are carried out according to normal conditions or manufacturer recommendations. The reagents used or the instruments that are not indicated by the manufacturer are conventional products that can be obtained commercially. The application should not be construed as being limited to the specific examples described.

[0106] 1. Raw materials

[0107] Tridecafluorooctyl acrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0108] 1H,1H,7H-Perfluoroheptyl acrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0109] 2,2,3,3,4,4,4-Heptafluorobutyl acrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0110] Octadecyl acrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0111] Hexadecyl acrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0112] Tetradecyl acrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0113] Dodecyl acrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0114] Hydroxyethyl methacrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0115] Hydroxyethyl acrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0116] Octadecyl methacrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0117] Tridecafluorooctyl methacrylate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0118] Ammonium persulfate: analytical grade, Beijing Bailingwei Technology Co., Ltd.;

[0119] Sodium dodecyl sulfate: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0120] Dodecylphenol polyoxyethylene ether: analytical grade, Chengdu Kelong Chemical Co., Ltd.;

[0121] Deionized water: homemade in the laboratory.

[0122] 2. Test methods

[0123] Contact angle test: The water contact angle (WCA) and oil contact angle (OCA) of the sample surface were measured using a contact angle tester (JC2000D2H instrument, Zhongchen digital equipment Co. Ltd, Shanghai, China). The test droplet volume was set to 5 μL, and the test was performed at least three times at different locations on the sample surface. The average value and standard deviation were taken.

[0124] Contact angle hysteresis: The advancing and receding contact angles of the samples were measured using a contact angle tester (DSA25E, Krüss GmbH, Germany). The sample testing method adopted the liquid addition and subtraction method. The test was performed at different positions on the sample surface at least three times, and the average value and standard deviation were calculated.

[0125] Washing resistance test: The sample was immersed in 150 mL of an aqueous solution containing 0.15 wt% laundry detergent, then placed on a heat-collecting constant temperature heating magnetic stirrer (DF-101S) and stirred at 49°C and 500 rpm for 45 minutes. The washed sample was then removed, rinsed with deionized water, and dried in an 80°C oven. This was counted as one cycle. The water contact angle of the sample was measured after every 20 cycles. The test was performed at least three times at different locations on the sample surface, and the average value and standard deviation were taken.

[0126] Sample morphology test: A desktop scanning electron microscope (SEM, Phenom ProX) was used to observe the surface morphology of the samples at a test voltage of 10 kV.

[0127] 3. Preparation method

[0128] (1) 0.41 g of sodium lauryl sulfate and 0.19 g of dodecylphenol polyoxyethylene ether were added to 50 ml of deionized water, stirred and dispersed for 0.5 to 1 hour to properly emulsify them, and then a comonomer was added thereto and stirred uniformly to obtain a comonomer dispersion, wherein the solid content of the comonomer was 25 wt%;

[0129] (2) placing the comonomer dispersion obtained in step (1) in a homogenizer and homogenizing and dispersing at 8000-10000 rpm for 15-30 minutes to obtain a pre-emulsion;

[0130] (3) Dissolve 0.19 g of ammonium persulfate in 10 ml of deionized water to prepare an initiator solution;

[0131] (4) Under inert gas protection, the pre-emulsion obtained in step (2) and the initiator obtained in step (3) are dissolved and added into a reaction vessel, and the mixture is stirred under condensation reflux at 75-80° C. for 5-7 h, and the pH of the product is adjusted to neutral to prepare an environmentally adaptable water-based durable short-chain fluorine-containing water- and oil-repellent coating.

[0132] When in use, the prepared environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating is applied to a substrate by dipping or spraying, and a stable coating is formed after about 4 hours, which is used as a test sample.

[0133] Examples 1 to 13

[0134] Examples 1 to 13 are prepared in accordance with the above-mentioned "3. Preparation Method", with the specific selection of the comonomer and the molar ratio of the comonomer as variables. In each example, the environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating prepared was used as a sample and tested with reference to the above-mentioned "2. Test Method". The test results are shown in Table 1:

[0135] Table 1 Glass surface wetting properties

[0136]

[0137] In Examples 1 to 13, component A corresponds to a short-chain fluorinated acrylate monomer, component B corresponds to a crystallizable acrylate monomer, and component C corresponds to an acrylic functional monomer;

[0138] In Examples 1 to 10, the molar ratio of component A, component B, and component C is 3:1:1;

[0139] In Example 11, the molar ratio of component A, component B, and component C is 1:5:1;

[0140] In Example 12, the molar ratio of component A, component B, and component C is 1:3:1;

[0141] In Example 13, the molar ratio of component A, component B, and component C is 1:1:1;

[0142] From the above test results, it can be seen that when the short-chain fluorinated acrylate monomer is selected as tridecafluorooctyl acrylate and the crystallizable acrylate monomer is selected as octadecyl acrylate, and the molar ratio of the two is 3:1, better overall water and oil repellency is exhibited.

[0143] Examples 14 to 17

[0144] Examples 14 to 17 are in accordance with the above-mentioned "3. Preparation method", and the comonomers are selected as short-chain fluorinated acrylate monomers and crystallizable acrylate monomers, and the specific selection of the comonomers is used as a variable. In each example, the environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coatings prepared are used as samples and tested with reference to the above-mentioned "2. Test method". The test results are shown in Table 2:

[0145] Table 2 Surface wetting properties and washing resistance test of cotton fabric

[0146]

[0147] Note: The number of washing cycles in Table 2 is when the water contact angle is less than 140° and the washing cycle is stopped. The number of washing cycles in which the water contact angle is maintained above 140° is recorded.

[0148] In Examples 14 to 17, component A corresponds to a short-chain fluorinated acrylate monomer, component B corresponds to a crystallizable acrylate monomer, and component C corresponding to an acrylic functional monomer is not added;

[0149] In Examples 14 to 17, the molar ratio of component A to component B is 3:1.

[0150] From Table 2 and other tests, it can be found that the coating prepared by the binary copolymer has the disadvantages of poor adhesion, poor water resistance, low glass transition temperature, and easy softening and deformation of the coating when used at room temperature.

[0151] In addition, it was found that the specific selection of crystallizable acrylate monomers in binary copolymers had little significant impact on product performance, which was completely different from the specific selection of crystallizable acrylate monomers in ternary copolymers, which significantly affected product performance.

Claims

1. A method for preparing an environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating, characterized in that The main steps include: (1) Adding a surfactant to a solvent, stirring and dispersing the mixture for 0.5 to 1 hour, then adding a comonomer and stirring the mixture to obtain a comonomer dispersion; The comonomers are tridecafluorooctyl acrylate, octadecyl acrylate and hydroxyethyl methacrylate in a molar ratio of 3:1:1, and the solid content of the comonomers in the dispersion is 25 wt%; (2) placing the comonomer dispersion obtained in step (1) in a homogenizer and homogenizing and dispersing at 8000-10000 rpm for 15-30 minutes to obtain a pre-emulsion; (3) dissolving the initiator in a solvent to prepare an initiator solution; (4) Under inert gas protection, the pre-emulsion obtained in step (2) and the initiator obtained in step (3) are dissolved and added into a reaction vessel, and the mixture is stirred under condensation reflux at 75-80° C. for 5-7 hours, and the pH of the product is adjusted to neutral to prepare an environmentally adaptable water-based durable short-chain fluorine-containing water- and oil-repellent coating; The main component of the environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating is a terpolymer obtained by random copolymerization of tridecafluorooctyl acrylate, octadecyl acrylate and hydroxyethyl methacrylate; The general chemical structure of the terpolymer is as follows: ， Wherein R1=-H or -CH3; R2= -CH2CH2(CF2)5CF3; <h2 style=";text-align:left;direction:ltr">R3= -(CH2)<h2 style=";text-align:left;direction:ltr"> 17 <h2 style=";text-align:left;direction:ltr"> CH3; R4 = -CH2CH2OH; X, Y, and Z are the numbers of repeating units, and are all no greater than 100.

2. The environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating prepared by the method for preparing the environmentally adaptable water-based durable short-chain fluorinated water- and oil-repellent coating as claimed in claim 1.

3. Application of the environmentally adaptable water-based durable short-chain fluorine-containing water- and oil-repellent coating as claimed in claim 2 in polymer material substrates and inorganic material substrates.

Images