Bio-based surfactant, fluorine-containing acrylate polymer and preparation methods of bio-based surfactant and fluorine-containing acrylate polymer

Abstract

The invention relates to the technical field of surfactants, in particular to a bio-based surfactant, a fluorine-containing acrylate polymer and a preparation method, the structural formula of the bio-based surfactant is as follows: # imgabs0 #, and the preparation method of the bio-based surfactant comprises the following steps: mixing cyclosporine A, isopropanol, a sodium hydrogen sulfite solution, organic alkali and an initiator in a constant-temperature oil bath, and reacting at 39-42 DEG C for 18-25 hours. The bio-based surfactant disclosed by the invention is non-toxic and degradable, and has excellent emulsifying capacity and water surface energy reducing capacity.

Description

Technical Field

[0001] The present invention relates to the technical field of surfactants, and in particular to a bio-based surfactant, a fluorine-containing acrylate polymer and a preparation method thereof. Background Art

[0002] PFAS (per- and polyfluoroalkyl substances) are widely used in the preparation of fluorinated rubber, fire protection, pesticides, mineral processing, papermaking, leather and other fields, such as the most common perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS).

[0003] Since the environmental problem of PFOS-type fluorocarbon surfactants is due to the long length of their fluorocarbon chains, which are difficult to degrade in nature and organisms, the current global PFOS substitute research and development strategy is mainly focused on reducing the toxicity of the fluorocarbon chain, such as reducing the length of the fluorocarbon chain (such as PFHS with a hydrophobic fluorocarbon chain length of 6 carbons and PFBS with a hydrophobic fluorocarbon chain length of 4 carbons), introducing more easily degradable weak sites in the fluorocarbon chain (such as the methylene group in vinylidene fluoride oligomers and the ether bond in hexafluoropropylene oxide oligomers), branching the fluorocarbon chain (such as hexafluoropropylene oligomers), constructing new fluorocarbon surfactant structures (such as gemini surfactants and heterogemini surfactants), etc. For example, the surfactant constructed by CN 118955321 A circumvents the ban on PFAS by reducing the total number of fluorine-containing carbons, and CN 117903346 A introduces oxygen heteroatoms to increase the weak points of the chain segments, thereby achieving the preparation of degradable surfactants, but none of them fundamentally solves the toxicity and potential bioaccumulation of fluorinated compounds.

[0004] All of them are aimed at modifying the fluorinated chain segments, and they achieve the purpose of biodegradability by shortening the fluorinated chain segments or increasing the weak points in the chain, thereby avoiding the PFAS regulations. However, they still have bioaccumulation and are harmful to the human body. At the same time, the synthesis of most surfactants is relatively complicated and the steps are cumbersome. With the continuous improvement of environmental awareness, this type of compound has been gradually controlled and banned, and cannot be used as an emulsifier in the emulsion polymerization of rubber. Summary of the invention

[0005] The object of the present invention is to provide a bio-based surfactant and a preparation method thereof, wherein the bio-based surfactant is not only non-toxic and degradable, but also has excellent emulsification ability and the ability to reduce water surface energy.

[0006] In addition, the present invention also provides a fluorine-containing acrylic polymer prepared from the above-mentioned bio-based surfactant and a preparation method thereof; the bio-based surfactant exhibits excellent emulsification effect in the emulsion polymerization of fluorine-containing monomers, and the obtained emulsion has high stability.

[0007] The present invention is achieved through the following technical solutions:

[0008] Bio-based surfactant, its structural formula is as follows:

[0009]

[0010] The bio-based surfactant of the present invention is a non-fluorine surfactant. The bio-based surfactant is not only non-toxic and degradable, but also has excellent emulsification ability and the ability to reduce water surface energy.

[0011] A method for preparing a bio-based surfactant comprises placing cyclosporine A, isopropanol, sodium bisulfite solution, an organic base and an initiator in a constant temperature oil bath, mixing them, and reacting them at 39-42° C. for 18-25 hours.

[0012] In a preferred embodiment, the organic base includes at least one of triethylamine, diisopropylamine and tetramethylethylenediamine.

[0013] In a preferred embodiment, the initiator includes at least one of tert-butyl perbenzoate, benzoyl peroxide and tert-butyl hydroperoxide.

[0014] In a preferred embodiment, based on the molar ratio of cyclosporin A, the sodium bisulfite is 2-5%; the organic base is 2-8%; and based on the mass of cyclosporin, the initiator is 2-15%.

[0015] The invention discloses an application of a bio-based surfactant as an emulsifier in the preparation of rubber latex.

[0016] A fluorine-containing acrylic polymer is obtained by carrying out a polymerization reaction using a fluorine-containing acrylic ester as a raw material and a bio-based surfactant as an emulsifier; the fluorine-containing acrylic ester includes at least one of hexafluorobutyl acrylate, tridecafluorooctyl acrylate and hexafluorobutyl methacrylate.

[0017] A method for preparing a fluorine-containing acrylic polymer comprises the following steps:

[0018] S1, mixing fluorinated acrylate, bio-based surfactant and solvent to obtain a pre-emulsion;

[0019] S2, in the presence of an initiator, mixing the pre-emulsion in step S1 with a solvent and initiating a reaction to obtain a reaction solution;

[0020] S3, mixing the pre-emulsion in step S1, the initiator and the reaction solution prepared in step S2, and performing a polymerization reaction to obtain a fluorine-containing acrylate polymer.

[0021] In a preferred embodiment, the initiator in step S2 and step S3 is potassium persulfate.

[0022] In a preferred embodiment, the solvent in step S1 and step S2 includes water.

[0023] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0024] 1. The bio-based surfactant synthesized by the present invention is non-toxic, biodegradable, ecologically safe and has high surface activity. At the same time, the preparation method of the bio-based surfactant of the present invention is most effective for the addition of double bonds by using a catalytic system composed of an organic base and an organic peroxide. The reaction conditions are simple and easy to operate, and it is suitable for industrial production. It has the advantages of short synthesis steps and simple actual operation. At the same time, it shows a good emulsifying effect in the polymerization of fluorinated acrylate monomers, the reaction time is short, and the obtained emulsion is stable, which can greatly improve the reaction efficiency.

[0025] 2. The raw material of the bio-based surfactant obtained in the present invention is cyclosporine A obtained by fungal fermentation. The source of the raw material complies with green chemistry, and there is no environmental pollution problem during the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0027] Figure 1 This is the infrared spectrum of the bio-based surfactant prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the embodiments. The schematic implementation mode of the present invention and its description are only used to explain the present invention and are not intended to limit the present invention. The embodiments described below are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0029] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to those of ordinary skill in the art that these specific details do not have to be employed to practice the present invention. In other embodiments, in order to avoid confusing the present invention, known structures, materials or methods are not specifically described. The materials, instruments and reagents used in the following examples, unless otherwise specified, can be obtained from commercial sources. The technical means used in the examples, unless otherwise specified, are conventional means well known to those skilled in the art.

[0030] In order to solve the problems of toxicity and complicated synthesis process of existing non-fluorinated surfactants, this embodiment provides a bio-based surfactant, whose structural formula is as follows:

[0031]

[0032] The preparation method of the bio-based surfactant comprises placing cyclosporine A, isopropanol, sodium bisulfite solution, organic base and initiator in a constant temperature oil bath for mixing and reacting at 39-42° C. for 18-25 hours.

[0033] The synthesis routes of the above bio-based surfactants are as follows:

[0034]

[0035] In this embodiment, cyclosporin A is a cyclic peptide molecule composed of 11 amino acids. By using the double bond of the active functional group above, an addition reaction occurs with sodium bisulfite. Through a series of condition optimization, a new type of bio-based cyclosporin A sodium sulfonate non-fluorinated surfactant can be constructed, wherein the intiator is tert-butyl peroxybenzoate (TBPB), benzoyl peroxide (BPO) or tert-butyl hydroperoxide (TBHP), X is 2, 4, 6, 10, 12, 15 of the raw material mass percentage. Y is 2, 3, 4, 5 of the raw material molar ratio. Base is an organic base such as triethylamine, diisopropylamine or tetramethylethylenediamine, and Z is 2, 4, 8 of the raw material molar ratio.

[0036] The raw material of the bio-based surfactant of this embodiment is cyclosporin A obtained by fungal fermentation. The source of the raw material complies with green chemistry, and there is no environmental pollution problem in the production process. In addition, this embodiment is most effective for the addition of double bonds by using a catalytic system composed of an organic base and an organic peroxide. The reaction conditions are simple and easy to operate, and suitable for industrial production. The prepared bio-based can effectively reduce the surface tension of the aqueous solution, has good solubility, low foaming, fine foam, and excellent surfactant performance.

[0037] The bio-based surfactant can be used as an emulsifier in the preparation of rubber latex, specifically, in the preparation of fluorine-containing acrylic polymers.

[0038] The method for preparing the above-mentioned fluorine-containing acrylic polymer comprises the following steps:

[0039] S1, mixing fluorinated acrylate, bio-based surfactant and solvent to obtain a pre-emulsion;

[0040] S2, in the presence of an initiator, mixing the pre-emulsion in step S1 with a solvent and initiating a reaction to obtain a reaction solution;

[0041] S3, mixing the pre-emulsion in step S1, the initiator and the reaction solution prepared in step S2, and performing a polymerization reaction to obtain a fluorine-containing acrylate polymer.

[0042] The initiator in step S2 and step S3 is potassium persulfate, which is preferably used in the form of an aqueous solution.

[0043] Wherein, the solvent in step S1 and step S2 includes water, such as distilled water.

[0044] The route of the above fluorinated acrylic polymer is as follows:

[0045]

[0046] Wherein, Formula I is an emulsifier (bio-based surfactant); R 1 H or Me, R 2 is perfluorohexylethyl or hexafluoropropylmethyl; Formula II specifically represents that the fluorinated acrylate includes at least one of hexafluorobutyl acrylate, tridecafluorooctyl acrylate and hexafluorobutyl methacrylate.

[0047] The weight proportion of the compound represented by formula II is 0.1 to 10 parts, preferably 1 to 7 parts; the weight proportion of the compound represented by formula I is 0.01 to 1.0 parts, preferably 0.02 to 0.07 parts, for example 0.03 parts.

[0048] In order to better illustrate the technology of this embodiment, the following specific case is used for illustration:

[0049] Embodiment 1:

[0050] A method for preparing a bio-based surfactant:

[0051] Cyclosporine A (12.02 g, 0.01 mol), isopropanol (10 mL), sodium bisulfite (4.16 g, 0.4 mol), triethylamine (0.3 g, 2.0% molar ratio relative to substrate cyclosporine A) and TBPB (0.60 g, 5.0% mass ratio relative to substrate cyclosporine A) dissolved in distilled water (10 mL) were added in sequence in a 250 mL three-necked round-bottom flask, and the molar ratio of sodium bisulfite relative to cyclosporine A was 4; the mixture was placed in a constant temperature oil bath, stirred thoroughly, and reacted at (40±0.5)°C for 20 h. After the reaction was completed, petroleum ether and distilled water were added for extraction, the aqueous phase was collected, and anhydrous ethanol was added for desalination. After filtering, the solvent was removed by rotary evaporation, and a white powder product was obtained after washing with water, with a yield of 80%.

[0052] The infrared spectrum of the bio-based surfactant prepared in this example is as follows Figure 1 As shown: Through the infrared data, it can be seen that at 1695cm -1 -1630cm -1 No stretching vibration peaks of olefins were observed, so the double bond had been reacted.

[0053] Embodiment 2:

[0054] A method for preparing a bio-based surfactant:

[0055] Cyclosporine A (12.02 g, 0.01 mol), isopropanol (10 mL), sodium bisulfite (4.16 g, 0.4 mol), diisopropylamine (0.2 g, 2.0% molar ratio relative to substrate cyclosporine A) and dibenzoyl peroxide (BPO) (0.60 g, 5.0% mass ratio relative to substrate cyclosporine A) dissolved in distilled water (10 mL) were added in sequence in a 250 mL three-necked round-bottom flask, and the molar ratio of sodium bisulfite relative to cyclosporine A was 4; placed in a constant temperature oil bath, stirred thoroughly, and reacted at (40 ± 0.5) ° C for 20 h. After the reaction was completed, petroleum ether and distilled water were added for extraction, the aqueous phase was collected, and anhydrous ethanol was added for desalination. After filtering, the solvent was removed by rotary evaporation, and water was added for washing to obtain a white powder product with a yield of 75%.

[0056] Embodiment 3:

[0057] A method for preparing a bio-based surfactant:

[0058] Cyclosporine A (12.02 g, 0.01 mol), isopropanol (10 mL), sodium bisulfite (4.16 g, 0.4 mol), tetramethylethylenediamine (0.2 g, 2.0% molar ratio relative to substrate cyclosporine A) and tert-butyl hydroperoxide (TBHP) (0.60 g, 5.0% mass ratio relative to substrate cyclosporine A) dissolved in distilled water (10 mL) were added in sequence in a 250 mL three-necked round-bottom flask, and the molar ratio of sodium bisulfite relative to cyclosporine A was 4; the mixture was placed in a constant temperature oil bath, stirred thoroughly, and reacted at (40±0.5)°C for 20 h. After the reaction was completed, petroleum ether and distilled water were added for extraction, the aqueous phase was collected, and anhydrous ethanol was added for desalination. After filtering, the solvent was removed by rotary evaporation, and water was added for washing to obtain a white powder product with a yield of 77%.

[0059] Comparative Example 1:

[0060] A method for preparing a bio-based surfactant:

[0061] Cyclosporine A (12.02 g, 0.01 mol), isopropanol (10 mL), sodium bisulfite (4.16 g, 0.4 mol) dissolved in distilled water (10 mL), and tetramethylethylenediamine (0.2 g, 2.0% molar ratio relative to substrate cyclosporine A) were added to a 250 mL three-necked round-bottom flask in sequence, and the mixture was placed in a constant temperature oil bath, stirred thoroughly, and reacted at (40±0.5)°C for 20 h. After the reaction was completed, TLC monitoring showed that the raw materials were not reacted and no corresponding product was obtained.

[0062] Comparative Example 2:

[0063] A method for preparing a bio-based surfactant:

[0064] Cyclosporine A (12.02 g, 0.01 mol), isopropanol (10 mL), sodium bisulfite (4.16 g, 0.4 mol), K2CO3 (0.2 g, 2.0% molar ratio relative to substrate cyclosporine A), and TBPB (0.60 g, 5.0% mass ratio relative to substrate cyclosporine A) were added to a 250 mL three-necked round-bottom flask in sequence, and the mixture was placed in a constant temperature oil bath, stirred thoroughly, and reacted at (40±0.5)°C for 20 h. After the reaction was completed, TLC monitoring showed that the raw materials were not reacted and no corresponding product was obtained.

[0065] Embodiment 4:

[0066] A method for preparing a fluorinated acrylic polymer:

[0067] Dissolve 0.3g of formula INFS in 10g of ultrapure water to obtain a transparent clear solution. Add 10g of a mixture of hexafluorobutyl acrylate and tridecafluorooctyl acrylate (7:3) under stirring. After stirring at room temperature for 30 minutes, add 10g (0.03% wt) of KPS (potassium persulfate) aqueous solution. After stirring at room temperature for ten minutes, replace N2 and heat to 70°C for 6 hours. After the reaction is completed, pour into saturated brine to break the emulsion, wash and dry to obtain 9.78g of fluorinated polymer.

[0068] Embodiment 5:

[0069] A method for preparing a fluorinated acrylic polymer:

[0070] Dissolve 0.3g of Formula I NFS in 10g of ultrapure water to obtain a transparent clear solution, add 10g of 13-fluorooctyl acrylate under stirring, stir at room temperature for 30min, and then add 10g of KPS aqueous solution (0.03%wt). Stir at room temperature for ten minutes, replace N2 and heat to 70°C for 6h. After the reaction is completed, pour into saturated brine to break the emulsion, wash and dry to obtain 9.18g of fluorinated polymer.

[0071] Embodiment 6:

[0072] A method for preparing a fluorinated acrylic polymer:

[0073] Dissolve 0.3g of Formula I NFS in 10g of ultrapure water to obtain a transparent clear solution, add 10g of hexafluorobutyl acrylate under stirring, stir at room temperature for 30min, and then add 10g of KPS aqueous solution (0.03%wt). Stir at room temperature for ten minutes, replace N2 and heat to 70℃ for 6h. After the reaction is completed, pour into saturated brine to break the emulsion, wash and dry to obtain 9.55g of fluorine-containing polymer.

[0074] Embodiment 7:

[0075] A method for preparing a fluorinated acrylic polymer:

[0076] Dissolve 0.3g of Formula I NFS in 10g of ultrapure water to obtain a transparent clear solution, add 10g of a mixture of hexafluorobutyl acrylate and tridecafluorooctyl acrylate (6:4) under stirring, stir at room temperature for 30min, and then add 10g of KPS aqueous solution (0.03%wt). After stirring at room temperature for ten minutes, replace N2 and heat to 70°C for 6h. After the reaction is completed, pour into saturated brine to break the emulsion, wash and dry to obtain 9.23g of fluorinated polymer.

[0077] Embodiment 8:

[0078] A method for preparing a fluorinated acrylic polymer:

[0079] Dissolve 0.3g of Formula I NFS in 10g of ultrapure water to obtain a transparent clear solution, add 10g of a mixture of hexafluorobutyl acrylate and tridecafluorooctyl acrylate (5:5) under stirring, stir at room temperature for 30min, and then add 10g of KPS aqueous solution (0.03%wt). After stirring at room temperature for ten minutes, replace N2 and heat to 70°C for 6h. After the reaction is completed, pour into saturated brine to break the emulsion, wash and dry to obtain 9.22g of fluorinated polymer.

[0080] Bio-based surfactant performance test:

[0081] The comparison of the bio-based surfactant prepared in Example 1 with the commercially available sodium sulfonate surfactant in terms of emulsification ability, surface tension, demulsification time and total amount of agglomeration is shown in Table 1:

[0082] Table 1

[0083]

[0084] Emulsifying ability: According to the industry standard emulsifying ability test method, measure 40mL of the sample aqueous solution and 40mL of edible oil in a stoppered measuring cylinder and shake vigorously ten times. Let it stand and observe the time required for 10mL of water phase to precipitate.

[0085] Surface tension measurement: Sigma-700 test equipment was used to test according to GB / T 22237-2008 standard using the Wilhelmy plate method. When the plate enters the liquid, the interaction between the liquid and the plate will generate additional force. The surface tension of the liquid can be calculated using the Young-Laplace equation.

[0086] Demulsification time: Under the conditions of the above implementation case, the time required from the start of the reaction to the appearance of agglomerated products.

[0087] Total amount of agglomerates: under the conditions of the above implementation case, the total amount of agglomerates after the reaction is completed.

[0088] From Table 1, we can see that:

[0089] By comparing the differences in emulsification ability, surface tension, demulsification time and total agglomeration amount of different commercially available sodium sulfonate surfactants, it can be clearly observed that the bio-based surfactant prepared by the present invention has excellent emulsification ability and the ability to reduce the surface energy of water, and at the same time exhibits excellent emulsification effect in the emulsion polymerization of fluorinated monomers, and the obtained emulsion has high stability.

[0090] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A bio-based surfactant, characterized in that Its structural formula is as follows:

2. The method for preparing a bio-based surfactant according to claim 1, characterized in that: Cyclosporine A, isopropanol, sodium bisulfite solution, organic base and initiator are placed in a constant temperature oil bath and mixed, and reacted at 39-42° C. for 18-25 hours.

3. The preparation method according to claim 2, characterized in that: The organic base includes at least one of triethylamine, diisopropylamine and tetramethylethylenediamine.

4. The preparation method according to claim 2, characterized in that: The initiator includes at least one of tert-butyl perbenzoate, benzoyl peroxide and tert-butyl hydroperoxide.

5. The preparation method according to claim 2, characterized in that: Calculated by the molar ratio of the cyclosporin A, the sodium bisulfite is 2-5%; the organic base is 2-8%; and the initiator is 2-15% based on the mass of the cyclosporin.

6. Use of the bio-based surfactant as claimed in claim 1 as an emulsifier in the preparation of rubber latex.

7. Fluorinated acrylic polymer, characterized in that: The fluorinated acrylate is obtained by polymerization reaction with fluorinated acrylate as raw material and the bio-based surfactant as claimed in claim 1 as emulsifier; the fluorinated acrylate includes at least one of hexafluorobutyl acrylate, tridecafluorooctyl acrylate and hexafluorobutyl methacrylate.

8. The method for preparing a fluorinated acrylic polymer according to claim 7, wherein: The following steps are involved: S1, mixing the fluorinated acrylate, the bio-based surfactant and a solvent to obtain a pre-emulsion; S2, in the presence of an initiator, mixing the pre-emulsion in step S1 with a solvent and initiating a reaction to obtain a reaction solution; S3, mixing the pre-emulsion and initiator in step S1 and the reaction solution prepared in step S2, and performing a polymerization reaction to obtain the fluorine-containing acrylate polymer.

9. The preparation method according to claim 8, characterized in that: The initiator described in step S2 and step S3 is potassium persulfate.

10. The preparation method according to claim 8, characterized in that: The solvent in step S1 and step S2 includes water.

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