Surfactant as well as preparation method and application thereof

Abstract

The invention provides a surfactant and a preparation method and application thereof.The surfactant has the structure shown in the formula (I), raw materials of the surfactant are derived from phlorenic acid, ferulic acid and hydrogenated ferulic acid, and the surfactant has the advantages of being environmentally friendly and biosafe; a hydrophobic part in the structure contains an ester functional group, and has the characteristic of biodegradability; according to the surfactant disclosed by the invention, the hydrophilic size and the surface activity of the surfactant can be adjusted by controlling the length of polyoxyethylene, and the hydrophobic size and the surface activity of the surfactant can be adjusted by selecting fatty alcohols with different carbon numbers for esterification.

Description

Technical Field

[0001] The invention belongs to the field of fine chemical materials, and relates to a surfactant and a preparation method and application thereof, and in particular to a bio-based degradable surfactant and a preparation method and application thereof. Background Art

[0002] Surfactants are known as "industrial MSG" and are widely used in industrial production, daily chemicals, medical and health care and other fields.

[0003] Surfactants are substances that only need to be added in very small amounts to reduce the surface tension of a solvent. Surfactants have significant structural characteristics, namely, they are composed of a lipophilic tail group and a hydrophilic head group. Surfactants are substances that can associate molecules in aqueous solutions and form associations such as micelles, have high surface activity, and have wetting, emulsification, foaming, and washing functions.

[0004] Alkylphenol polyoxyethylene ether surfactant (APEO) is an important polyoxyethylene nonionic surfactant. It has the characteristics of stable properties, acid and alkali resistance and low cost. It is mainly used to produce high-performance detergents and is one of the most commonly used main raw materials in printing and dyeing auxiliaries. For a long time, alkylphenol polyoxyethylene ether has been needed to be added to various printing and dyeing auxiliaries such as detergents, scouring agents, spinning oils, softeners, crude oils and metal cleaners. OP-10 (octylphenol polyoxyethylene ether 10) and NP-10 (nonylphenol polyoxyethylene ether 10) are excellent representatives of APEO surfactants. They are easily soluble in water, resistant to acid, alkali, salt and hard water, and have good emulsification, leveling, wetting, diffusion and cleaning properties. They can be mixed with various surfactants and dyestuffs and are widely used as leveling agents and diffusants in printing and dyeing processing, leather and wool degreasing agents, crude oil and fuel oil emulsifiers, oil recovery acidification penetrants, styrene-butadiene latex and emulsion polymerization emulsifiers, glass fiber textile lubricants and emulsifiers, and emulsifying, washing, penetrating and wetting agents in cosmetics.

[0005] However, the environmental hormone problem of alkylphenol polyoxyethylene ether APEO has also attracted widespread attention. Environmental hormones refer to chemical substances that can invade the human body through various pathways, have effects similar to estrogen, and endanger the normal hormone secretion of the human body. NP and OP have been included in the list of 70 environmental hormone chemicals by the US Environmental Protection Agency. In 2016, EU REACH Annex XVII made corresponding restrictions and regulations on the use, circulation and emission of alkylphenol polyoxyethylene ether APEO. The restrictions on APEO in the regulations usually refer to four items: NPEO nonylphenol polyoxyethylene ether, NP nonylphenol, OPEO octylphenol polyoxyethylene ether, and OP octylphenol. The limit is: 100ppm. If the APEO content in the product exceeds the limit, it will not be allowed to be put on the EU market.

[0006] In order to find a good substitute for APEO, people have made many attempts. Among them, using bio-based cardanol to prepare cardanol polyoxyethylene ether structure non-ionic surfactant is an important method. Bruce et al. (Journal of Surfactants & Detergents, 2009, 12: 337-344.) used cardanol as raw material and methanol as solvent to react with vinyl sulfate to synthesize cardanol polyoxyethylene ether sulfate with a yield of 78%. The synthesis route is as follows:

[0007]

[0008] CN 200910017035 discloses a method for preparing ammonium salt of polyoxyethylene cardanol sulfate using polyoxyethylene cardanol as a raw material, and the product structural formula is as follows:

[0009]

[0010] CN200910017036.X and CN202110352871.X both disclose a cardanol polyoxyethylene ether and a preparation method thereof; CN200910052239.2 and CN202011342639.X disclose a method for preparing a cardanol sulfonate surfactant by sulfonating cardanol and then neutralizing it with an alkali.

[0011] Scorzza et al. (Journal of Surfactants & Detergents, 2010, 13(1):27) prepared two types of cardanol carboxylate surfactants using cardanol as raw material. The specific synthesis routes are as follows:

[0012]

[0013] The carboxylate surfactant has strong hydrophilicity, good surface activity and low critical micelle concentration.

[0014] Wang Jun et al. (Chemistry and Bioengineering, 2013, (4): 33-35) prepared a new cationic surfactant of cardanol using cardanol, epichlorohydrin and trimethylamine as raw materials, with a yield of 56%, of which the quaternary ammonium salt content was 80%. The synthesis route is as follows:

[0015]

[0016] Although cardanol can be used to prepare various alkylphenol-based surfactants, it has the following disadvantages: First, its alkyl chain is an unsaturated segment of 15 carbon atoms, which is much longer than the 8- and 9-carbon alkyl groups in the structures of OP-10 and NP-10, affecting its surface activity efficiency; second, its alkyl chain is located in the meta position of the phenolic hydroxyl group on the benzene ring, which is different from the para position of the alkyl chain of OP-10 and NP-10, which also affects its emulsification and dispersibility. Therefore, it is necessary to find a better APEO surfactant. Summary of the invention

[0017] In view of the deficiencies in the prior art, the object of the present invention is to provide a surfactant and a preparation method and application thereof, and in particular to provide a bio-based degradable surfactant and a preparation method and application thereof.

[0018] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0019] In one aspect, the present invention provides a surfactant having a structure shown in formula (I):

[0020]

[0021] Wherein, R1 is an alkyl group having 4 to 16 carbon atoms, R2 is hydrogen or methoxy, X is a carbon-carbon single bond or a carbon-carbon double bond; and n is a natural number of 3-30.

[0022] In the present invention, the surfactant is a phloric acid derivative nonionic surfactant, the raw materials of which are derived from phloric acid, ferulic acid and hydrogenated ferulic acid, and it has the characteristics of being green, environmentally friendly, biosafe and biodegradable.

[0023] In the present invention, R1 is an alkyl group having 4 to 16 carbon atoms, for example, the carbon atoms may be 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16. n is a natural number of 3-30, for example, 3, 4, 5, 6, 8, 10, 12, 14, 15, 17, 19, 20, 22, 24, 25, 26, 28 or 30, etc.

[0024] Preferably, the surfactant is any one of the following compounds:

[0025]

[0026]

[0027] On the other hand, the present invention provides a method for preparing the surfactant as described above, the preparation method comprising the following steps:

[0028] (1) Compound A reacts with compound B to obtain compound C. The reaction formula is as follows:

[0029]

[0030] (2) Compound C reacts with ethylene oxide to obtain a surfactant represented by formula (I), and the reaction formula is as follows:

[0031]

[0032] wherein R1, R2, X and n are the same as defined above.

[0033] Preferably, the compound A is any one of phloric acid, ferulic acid or hydrogenated ferulic acid.

[0034] The invention adopts bio-based phloric acid, ferulic acid and hydrogenated ferulic acid as raw materials, and prepares bio-based nonionic surfactants through esterification and oxyethylation to replace traditional alkylphenol surfactants.

[0035] Phloric acid, ferulic acid and hydrogenated ferulic acid (structural formulas as follows) are all p-carboxyethylphenol, which has a structure and properties similar to alkylphenols and can be modified to prepare bio-based materials and raw materials.

[0036] In the present invention, the structure of phlorotactic acid, ferulic acid or hydrogenated ferulic acid is as follows:

[0037]

[0038] Preferably, the molar ratio of compound A to compound B is 1:(0.85-2.0), for example, it can be 1:0.85, 1:0.9, 1:0.95, 1:1, 1:1.2, 1:1.4, 1:1.5, 1:1.7, 1:1.8, 1:1.9 or 1:2.0, etc.

[0039] Preferably, the reaction temperature in step (1) is 80-180°C, for example 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C or 180°C, and the reaction time is 8-28 hours, for example 8 hours, 10 hours, 12 hours, 14 hours, 16 hours, 18 hours, 20 hours, 22 hours, 24 hours, 26 hours or 28 hours.

[0040] Preferably, the molar ratio of compound C to ethylene oxide in step (2) is 1:3-30, for example 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:18, 1:20, 1:22, 1:24, 1:26, 1:28 or 1:30, etc.

[0041] Preferably, the reaction in step (2) is carried out in the presence of a catalyst.

[0042] Preferably, the catalyst is selected from at least one of sodium hydroxide, potassium hydroxide, boron trifluoride or boron trifluoride etherate.

[0043] Preferably, the reaction temperature in step (2) is 50-80°C, for example 50°C, 55°C, 58°C, 60°C, 65°C, 70°C, 75°C or 80°C, and the reaction time is 3-8 hours, for example 3 hours, 4 hours, 5 hours, 6 hours, 7 hours or 8 hours.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The surfactant of the present invention has raw materials derived from phloric acid, ferulic acid and hydrogenated ferulic acid, and has the characteristics of being green, environmentally friendly and biosafe; the hydrophobic part in its structure contains an ester functional group and has the characteristic of being biodegradable; the surfactant of the present invention can adjust its hydrophilicity and surface activity by controlling the length of polyoxyethylene, and can also adjust its hydrophobicity and surface activity by selecting fatty alcohols with different carbon numbers for esterification. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is the hydrogen nuclear magnetic spectrum of n-hexyl phlorothiate.

[0047] Figure 2 This is the hydrogen nuclear magnetic spectrum of bio-based surfactant 1#.

[0048] Figure 3 This is the H NMR spectrum of 2-ethylhexyl ferulate.

[0049] Figure 4 This is the H NMR spectrum of bio-based surfactant 2#.

[0050] Figure 5 This is the H NMR spectrum of n-hexyl ferulate.

[0051] Figure 6 This is the hydrogen nuclear magnetic spectrum of bio-based surfactant 3#. DETAILED DESCRIPTION

[0052] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0053] Example 1

[0054] In this example, bio-based surfactant 1# was prepared by the following method:

[0055] (1) Add 256 g (1.54 mol) of phloric acid, 133.6 g (1.308 mol) of n-hexanol, 3.8 g (1 wt%) of p-toluenesulfonic acid monohydrate, and 600 mL of cyclohexane into a 2000 mL four-necked flask. Install a water separator to collect the water generated during the reaction, heat the oil bath to 80°C, condense and reflux for 8 h. Wash with 2000 mL of 5 wt% NaHCO3 aqueous solution three times to remove excess phloric acid and n-hexanol, collect the organic phase, dry it with 100 g of anhydrous magnesium sulfate, filter it, and evaporate the mother liquor to remove the solvent to obtain the intermediate phloric acid n-hexanol ester. The hydrogen nuclear magnetic spectrum shows: Figure 1 , its NMR data are as follows:

[0056] 1 HNMR (400MHz, DMSO) δ9.16 (s, 1H, -OH); δ7.00~6.96 (d, 2H, Ar-H); δ6.64~6.66 (d, 2H, Ar-H); δ3.99~3.96 (t, 2H, CH2CH2OCO); δ 2.74~2.70(s,2H,Ar-CH2CH2CO), δ2.55~2.50(s,2H,Ar-CH2CH2CO), δ1.51~1.24(d,8H,(CH2)4CH3); δ1.06~0.84(s,3H,CH3).

[0057] (2) Add 200 g (0.8 mol) of 1-hexyl phylloxetate intermediate to a metal reactor and add 50 g of anhydrous KOH tablets. While stirring, gradually introduce a mixture of ethylene oxide (253 g, 10 mol) and nitrogen until the pressure of the reaction system reaches 0.5 MPa. During the reaction, as ethylene oxide is consumed, the pressure of the reaction system gradually decreases. Nitrogen is continuously introduced to maintain the reaction pressure at 0.5 MPa until the reaction pressure stabilizes and no longer decreases, indicating that the ethylene oxide reaction is complete. Acetic acid is added to adjust the pH of the reaction system to a weak acid (pH = 6), and diatomaceous earth adsorbent is added for post-treatment, filtration, and dehydration to obtain bio-based surfactant 1#. The hydrogen nuclear magnetic spectrum shows Figure 2 , its NMR data are as follows:

[0058] 1HNMR (400MHz, DMSO) δ9.16(-OH); δ7.00~6.64(Ar-H); δ3.99~3.96(CH2CH2OCO); δ3.579~3.42(CH2CH2O) 10 ); δ1.51~1.24((CH2)4CH3); δ1.06~0.84(CH3).

[0059]

[0060] Example 2

[0061] In this example, bio-based surfactant 2# was prepared by the following method:

[0062] (1) Add 388.2 g (2 mol) of ferulic acid, 234.36 g (1.9 mol) of isooctyl alcohol (2-ethylhexanol), 6.2 g (1 wt%) of p-toluenesulfonic acid monohydrate, and 1000 mL of cyclohexane into a 2500 mL four-necked flask. Install a water separator to collect the water generated during the reaction, heat the mixture in an oil bath at 105°C, and reflux under condensation for 28 h. Wash the mixture three times with 2000 mL of 5 wt% NaHCO3 aqueous solution to remove excess ferulic acid and isooctyl alcohol. Collect the organic phase, dry it with 200 g of anhydrous magnesium sulfate, filter it, and remove the solvent by rotary evaporation to obtain the intermediate isooctyl ferulate. The hydrogen nuclear magnetic spectrum shows: Figure 3

[0063] 1 HNMR (400MHz, DMSO) δ9.21(s,1H,-OH); δ7.56~7.33(s,1H,Ar-H); δ7.33~7.12(s,1H,Ar-H); δ6.8~6.46(s,1H,Ar-H); δ4.06~4.04(s,2H,Ar-CH) ＝ CHCO), δ3.82(s,3H,Ar-OCH3), δ1.36~1.34(m,1H,-O-CH2CH(CH2CH3)CH2CH2CH2CH3);

[0064] δ1.32~1.29(d,2H,-O-CH2CH(CH2CH3)CH2CH2CH2CH3);

[0065] δ1.28~1.26(d,8H,-O-CH2CH(CH2CH3)CH2CH2CH2CH3);

[0066] δ0.90~0.86(d,6H,-O-CH2CH(CH2CH3)CH2CH2CH2CH3).

[0067] Add 306.2g (1mol) of isooctyl ferulate intermediate and 52g of anhydrous KOH tablets into a metal reactor, and gradually introduce a mixture of ethylene oxide (220g, 5mol) and nitrogen while stirring until the pressure of the reaction system reaches 0.5M Pa. During the reaction, as ethylene oxide is consumed, the pressure of the reaction system gradually decreases. Nitrogen is continuously introduced to maintain the reaction pressure at 0.5MPa until the reaction pressure stabilizes and no longer decreases, indicating that the ethylene oxide reaction is complete. Acetic acid is added to adjust the pH of the reaction system to a weak acid (pH = 6), and diatomaceous earth adsorbent is added for post-treatment, filtration, and dehydration to obtain a bio-based surfactant 2#, with a hydrogen nuclear magnetic spectrum showing Figure 4 . 1 HNMR (400 MHz, DMSO) δ3.57-3.52 is the peak of the methylene (CH2CH2O) in the polyether segment, and δ1.38-0.87 is the peak of the alkyl group of isooctyl ester.

[0068]

[0069] Example 3

[0070] In this example, bio-based surfactant 3# was prepared by the following method:

[0071] (1) Add 392.4 g (2 mol) of hydrogenated ferulic acid, 408.4 g (4 mol) of n-hexanol, and 0.4 g (0.5 wt‰) of tetrabutyl titanate into a 2500 mL four-necked flask. Introduce nitrogen to drive away the air in the reaction flask, raise the temperature to 200°C, and evacuate the system to -0.05 MPa with a water pump to remove the moisture generated during the reaction. The reaction is continued for 10 hours. Raise the temperature to 230°C, and evacuate the system to -0.1 MPa with an oil pump to remove the excess n-hexanol in the reaction system. Keep the temperature for 5 hours until no more moisture and hexanol are extracted. Cool the reaction system to room temperature, and wash the obtained oily product with a 5 wt% NaHCO3 aqueous solution three times to remove the excess hydrogenated ferulic acid and hexanol. After collecting the organic phase, dry the organic phase with 200 g of anhydrous magnesium sulfate, filter, and the mother liquor is the product. The intermediate hydrogenated ferulic acid n-hexyl ester is obtained. The hydrogen nuclear magnetic spectrum shows: Figure 5 .

[0072] 1HNMR (400MHz, DMSO) δ9.56(s,1H,-OH); δ7.61~7.57(s,1H,Ar-H); δ7.38(s,1H,Ar-H); δ7.18~7.15(s,1H,Ar-H); δ6.85~6.51(s,2H,Ar-CH2CH2CO), δ4.18~4.15(s,3H,Ar-OCH 3), δ3.87(m,2H,Ar-CH2CH2CO); δ1.69~1.65(d,4H,-O-CH2CH2CH2CH2CH2CH3); δ1.28~ 1.26(d,6H,-O-CH2CH2CH2CH2CH2CH3); .δ0.94~0.91(q,3H,-O-CH2CH2CH2CH2CH2CH3).

[0073] (2) Add 280.2 g (1 mol) of hydrogenated ferulic acid n-hexyl ester intermediate into a metal reactor and add 40 g of anhydrous KOH tablets. While stirring, gradually introduce a mixture of ethylene oxide (880 g, 20 mol) and nitrogen until the pressure of the reaction system reaches 0.5 MPa. During the reaction, as ethylene oxide is consumed, the pressure of the reaction system gradually decreases. Nitrogen is continuously introduced to maintain the reaction pressure at 0.5 MPa until the reaction pressure stabilizes and no longer decreases, indicating that the ethylene oxide reaction is complete. Acetic acid is added to adjust the pH of the reaction system to a weak acid (pH = 6), and diatomaceous earth adsorbent is added for post-treatment, filtration, and dehydration to obtain a bio-based surfactant 3#. The hydrogen nuclear magnetic spectrum shows Figure 6 . 1 HNMR (400 MHz, DMSO), where: δ 3.57-3.52 is the peak of methylene (CH2CH2O) in the polyether segment.

[0074]

[0075] Example 4

[0076] In this example, bio-based surfactant 4# was prepared by the following method:

[0077] (1) Add 392.4 g (2 mol) of hydrogenated ferulic acid, 296.4 g (4 mol) of n-butanol, and 0.3 g (0.5 wt‰) of tetrabutyl titanate into a 2500 mL four-necked flask. Introduce nitrogen to drive away the air in the reaction flask, heat to 100° C., evacuate to -0.05 MPa with a water pump, and remove the moisture generated during the reaction. React for 12 hours. Heat to 110° C., evacuate to -0.1 MPa with an oil pump, and remove the excess n-butanol in the reaction system. Keep for 5 hours until no more moisture and n-butanol are removed. Cool the reaction system to room temperature, and wash the obtained oily product with 5 wt% NaHCO3 aqueous solution 3 times to remove the excess hydrogenated ferulic acid and n-butanol. After collecting the organic phase, dry the organic phase with 200 g of anhydrous magnesium sulfate, filter, and the mother liquor is the product, obtaining the intermediate hydrogenated ferulic acid n-butyl ester, 424 g.

[0078] (2) Add 252.1 g (1 mol) of the intermediate n-butyl hydroferulate and 5 g of boron trifluoride ether to a metal reactor, replace with nitrogen three times, evacuate to -0.1 MPa, turn off the vacuum, heat to 50°C, and slowly introduce a mixture of ethylene oxide (1320 g, 30 mol) and nitrogen. The reaction temperature is 50-70°C, and the pressure of the reaction system does not exceed 0.2 MPa. During the reaction, as ethylene oxide is consumed, the pressure of the reaction system gradually decreases. Nitrogen is continuously introduced, the temperature is raised to 70-80°C, the reaction pressure is maintained at 0.5 MPa, and the reaction is aged until the pressure is stable and no longer decreases. The temperature is lowered and the material is discharged to obtain a bio-based surfactant 4#.

[0079]

[0080] Example 5-Example 19

[0081]

[0082]

[0083] The structures of the compounds prepared in Examples 5 to 19 are as follows:

[0084]

[0085]

[0086] And the above compounds have been verified by H-NMR spectroscopy.

[0087] Performance Testing

[0088] Testing of dispersing properties of hyperdispersants

[0089] (1) Preparation of O / W emulsion

[0090] In an indoor environment at 25°C, 0.05 g of the bio-based surfactant prepared in the embodiment was weighed and dissolved in 50 mL of deionized water for later use; according to the set total oil / water volume (10 mL) and oil / water volume ratio, 5 mL of the previously prepared bio-based surfactant solution and 5 mL of the oil phase were weighed and placed in a small glass bottle (inner diameter = 1.6 cm, height = 7.2 cm), and homogenized and emulsified with a homogenizer at a speed of 13,0001 pm for 2 min, then allowed to stand for 0.5 hour to observe the emulsion stability and stratification.

[0091] There are three oil phases in total. Oil phase 1# is a mixture of styrene, methyl methacrylate, ethyl acrylate, and butyl acrylate. 苯乙烯 :V 甲基丙烯酸甲酯 :V 丙烯酸乙酯 :V 丙烯酸丁酯 =1:1:1:1; oil phase 2# is No. 36 white oil; oil phase 3# is soybean oil.

[0092] (2) Preparation of W / O emulsion

[0093] (a) Using n-hexadecane as the oil phase

[0094] First, prepare the oil solution of bio-based surfactant. Weigh a certain amount of bio-based surfactant and add it to the oil, and heat it at 80℃ to dissolve. Then transfer the required amount of bio-based surfactant oil solution and ultrapure water (the total volume of oil and water is 10mL) into a small bottle, put it in a 25℃ constant temperature box and let it stand and cool for 24 hours to ensure that the temperature of the sample is completely reduced to 25℃. Then, in a 25℃ indoor environment, use a homogenizer to homogenize the sample at a speed of 13,000rpm for 2min, and then let it stand for 0.5 hours to observe the emulsion stability and stratification.

[0095] (b) Edible oil as the oil phase

[0096] Due to the high viscosity of edible oil, the emulsion was prepared by the drop method. First, the bio-based surfactant was dissolved in the edible oil at high temperature (80°C), and then a certain volume of the oil solution of the bio-based surfactant was quickly transferred into the small bottle as described above with a pipette, and placed in a constant temperature box at 25°C for cooling. Then, at an ambient temperature of 25°C, 1m of ultrapure water was dropped into the oil dispersion within 30s and homogenized for 30s; 1m of ultrapure water was dropped into the oil dispersion again within 30s and homogenized for 30s. This was repeated until all the ultrapure water was dropped into the oil dispersion. For example, when the oil / water volume ratio is 5:5, the total homogenization time is 5min. Then it was left to stand for 0.5 hours to observe the emulsion stability and stratification.

[0097] (3) Determination of emulsion type

[0098] Use the droplet dispersion method to determine the type of emulsion. Prepare two small bottles, one filled with pure water and the other with n-hexadecane. Drop the emulsion into water and n-hexadecane respectively. If the emulsion disperses immediately when dropped into water, but does not disperse in oil and sinks to the bottom of the n-hexadecane phase, then the emulsion is an O / W emulsion. If the emulsion disperses immediately when dropped into n-hexadecane, but does not disperse when dropped into water and floats on the water surface in the form of a sphere, then it is a W / O emulsion.

[0099] (4) Determination of emulsion stability

[0100] When the emulsion is of O / W type, demulsification, stratification and coalescence will occur. The emulsion separation and coalescence stability can be characterized by measuring the volume or height of the precipitated water phase and oil phase to obtain the parameter f w and f o :

[0101]

[0102]

[0103] Where V w(t) and V o(t) Respectively refer to the volume of water phase and oil phase precipitated at time t; V w(0) and V o(0) Refers to the volume of the water phase and oil phase before homogenization. Parameter f w and f o The smaller the value, the better the stability of the emulsion. w and f o The closer the value is to 1, the worse the surface emulsion stability is.

[0104] Similarly, when the emulsion is of W / O type, sedimentation and agglomeration will also occur. Similarly, the parameter f can be obtained w and f o , which are used to represent aggregation and sedimentation stability, respectively.

[0105] Table 1

[0106]

[0107]

[0108] As shown in Table 1, except for Example 5 and Example 10, the bio-based surfactants in other examples can be prepared into O / W emulsions. wBy comparison, it is found that the water-in-oil emulsifiers prepared by Examples 1, 2, 6, 7, 11, 12, 13 and 16 all have better surface activity than OP-10 and NP-10. This indicates that the nonionic surfactants prepared by using ferulate, ferulate and hydrogenated ferulate have good surface activity like OP-10 and NP-10.

[0109] The applicant declares that the present invention illustrates the surfactant and its preparation method and application through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the raw materials selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A surfactant, characterized in that The surfactant has a structure shown in formula (I): Wherein, R1 is an alkyl group with 4 to 16 carbon atoms, R2 is hydrogen or methoxy, X is a carbon-carbon single bond or a carbon-carbon double bond; and n is a natural number of 3-30.

2. The surfactant according to claim 1, characterized in that The surfactant is any one of the following compounds:

3. The method for preparing a surfactant according to claim 1 or 2, characterized in that: The preparation method comprises the following steps: (1) Compound A reacts with compound B to obtain compound C. The reaction formula is as follows: (2) Compound C reacts with ethylene oxide to obtain a surfactant represented by formula (I), and the reaction formula is as follows: wherein R1, R2, X and n are defined as in claim 1.

4. The preparation method according to claim 3, characterized in that: The compound A is any one of phlorotactic acid, ferulic acid or hydrogenated ferulic acid.

5. The preparation method according to claim 3 or 4, characterized in that: The molar ratio of compound A to compound B is 1:(0.85-2.0).

6. The preparation method according to any one of claims 3 to 5, characterized in that: The reaction temperature in step (1) is 80-180° C. and the reaction time is 8-28 hours.

7. The preparation method according to any one of claims 3 to 6, characterized in that: The molar ratio of compound C to ethylene oxide in step (2) is 1:3-30.

8. The preparation method according to any one of claims 3 to 7, characterized in that: The reaction in step (2) is carried out in the presence of a catalyst.

9. The preparation method according to claim 8, characterized in that: The catalyst is selected from at least one of sodium hydroxide, potassium hydroxide, boron trifluoride or boron trifluoride ether.

10. The preparation method according to any one of claims 3 to 9, characterized in that: The reaction temperature of step (2) is 50-80° C., and the reaction time is 3-8 hours.

Images