阅读说明：本技术 一种低泡型α-生育酚表面活性剂及其制备方法 (Low-foam alpha-tocopherol surfactant and preparation method thereof ) 是由 宋冰蕾 陈豪 陈钊 庞淑敬 于 2020-06-30 设计创作，主要内容包括：本发明公开了一种低泡型α-生育酚表面活性剂及其制备方法,属于天然产物表面活性剂的合成与应用领域。本发明提供了一种α-生育酚表面活性剂及其制备方法,本发明中的α-生育酚表面活性剂具有极低的起泡性和稳泡性,初始泡沫体积为0.5毫升,泡沫半衰期小于3秒。制备本发明α-生育酚表面活性剂所用原料α-生育酚具有可再生、可生物降解、功能多样、结构易于修饰等优点,该表面活性剂的优良性能可以使其应用于金属清洗剂和个人洗护用品等领域。(The invention discloses a low-foam alpha-tocopherol surfactant and a preparation method thereof, belonging to the field of synthesis and application of natural product surfactants. The invention provides an alpha-tocopherol surfactant and a preparation method thereof, wherein the alpha-tocopherol surfactant has extremely low foamability and foam stability, the initial foam volume is 0.5ml, and the foam half-life period is less than 3 seconds. The raw material alpha-tocopherol used for preparing the alpha-tocopherol surfactant has the advantages of reproducibility, biodegradability, multiple functions, easy modification of structure and the like, and the excellent performance of the surfactant can enable the surfactant to be applied to the fields of metal cleaning agents, personal washing and nursing articles and the like.)

1. A compound having the formula i:

wherein M is Na or K.

2. A method for synthesizing the compound of claim 1, wherein the compound is synthesized by the following route:

wherein R is selected from C₂H₅，C₃H₇，C₄H₉，C₅H₁₁Wherein X is ClBr and I, and M is Na or K.

3. The method of claim 2, wherein the compound is synthesized by the steps of:

(1) mixing alpha-tocopherol and 2-ethyl haloate, and reacting under the catalysis of potassium carbonate to obtain alpha-tocopherol acid ester, which is marked as a compound 1;

(2) and (2) reacting the alpha-tocopherol acid ester obtained in the step (1) with NaOH or KOH to obtain a target product alpha-tocopherol carboxylate, and marking as a compound 2, namely the final product.

4. The method according to claim 2 or 3, wherein the specific synthetic steps of the compound are as follows:

(1) synthesis of Compound 1: get K₂CO₃Placed in a reaction vessel under N₂Adding α -tocopherol dissolved in aprotic solvent under protection, stirring, adding 2-halogenated acid ethyl ester dissolved in aprotic solvent, heating to 50-70 deg.C, and reacting₂CO₃Filtering to remove the aprotic solvent, extracting with petroleum ether, collecting the organic phase after liquid separation, removing the petroleum ether, and further purifying to obtain a purified compound 1;

(2) synthesis of Compound 2: adding the purified compound 1 into a reaction container, adding ethanol and NaOH/KOH for reaction at 70-95 ℃, standing and cooling the mixture after the reaction is finished, removing supernatant, washing the residual product with acetone/ethanol mixed solution, and drying in vacuum to obtain light yellow solid, namely the final product compound 2.

5. The process of claim 4, wherein the aprotic solvent in step (1) is DMF or acetone.

6. The method as claimed in claim 4, wherein the purification in step (1) is performed by using a 300-400 mesh silica gel chromatography column.

7. A metal cleaner characterized by containing the compound according to claim 1.

8. A cleaning agent for kitchenware, characterized in that it comprises the compound as claimed in claim 1.

9. A laundry detergent comprising a compound of claim 1.

10. A personal care product comprising a compound according to claim 1.

Technical Field

The invention relates to a low-foam alpha-tocopherol surfactant and a preparation method thereof, belonging to the field of synthesis and application of natural product surfactants.

Background

The low-foam surfactant is widely applied to industrial cleaning and personal care, and most of the traditional low-foam surfactants are nonionic surfactants of ethylene oxide-propylene oxide block polyether. Such surfactants are made primarily from petrochemicals. Under the condition of the increasing shortage of petroleum resources, the biological reduction foam type surfactant prepared by taking biomass resources as raw materials is the focus of attention of people at present.

Vitamin E is an important biological antioxidant in mammalian cell membranes, and its antioxidant action is essential to protect the integrity of the biological membrane — scavenging free radicals and breaking down further oxidative chain reactions, preventing oxidation of unsaturated fatty acids. In addition, vitamin E can also alleviate the negative effects of infectious diseases by enhancing cellular and humoral immunity. In recent years, vitamin E and derivatives thereof are found to have obvious effects on preventing Alzheimer's disease, inducing cancer cell specific apoptosis and inhibiting tumor angiogenesis. Vitamin E is a general term of four tocopherols and four tocotrienols, and alpha-tocopherol is considered as the most important active compound of the tocopherol and has the characteristics of low price, easy obtainment, regeneration, biodegradability and the like. From the perspective of molecular structure, the alpha-tocopherol contains long hydrophobic groups, and the carboxylate surfactant has the advantages of low irritation, good biocompatibility and the like. If the alpha-tocopherol is introduced into the structure of the carboxylate surfactant, a high-quality surfactant product with good affinity, good biodegradability and low skin irritation is hopeful to be obtained, and the product meets the requirements of current green chemical development. However, to date, there have been no reports of alpha-tocopherol surfactants.

Disclosure of Invention

[ technical problem ]:

most of the traditional low-foam surfactants are nonionic surfactants of ethylene oxide-propylene oxide block polyether type, and the surfactants are mainly prepared from petrochemicals, but nowadays, petroleum resources are in short supply. The vitamin E has the characteristics of low price, easy obtainment, reproducibility, biodegradability and the like. The alpha-tocopherol is introduced into the structure of the carboxylate surfactant, so that a high-quality surfactant product with good affinity, good biodegradability and low skin irritation is hopeful to be obtained, and the requirements of current green chemical development are met. However, to date, there have been no reports of alpha-tocopherol surfactants.

[ technical solution ]:

in order to achieve the above objects, the present invention provides a low foaming alpha-tocopherol surfactant and a method for preparing the same, which is a surfactant synthesized from alpha-tocopherol, which is a main component of vitamin E, as a raw material, and which exhibits excellent aggregation ability and high efficiency of reducing surface tension, and which has extremely low foaming and foam stabilizing properties.

The invention provides a compound, which has a structural formula shown as the following formula I:

wherein M is Na or K.

The invention provides a method for preparing the compound, and the synthetic route of the compound is as follows:

wherein R is selected from C₂H₅，C₃H₇，C₄H₉，C₅H₁₁X is selected from any one of Cl, Br and I, and M is Na or K.

In one embodiment of the invention, the synthesis of the compound is as follows:

(1) mixing alpha-tocopherol and 2-ethyl haloate, and reacting under the catalysis of potassium carbonate to obtain alpha-tocopherol acid ester, which is marked as a compound 1;

(2) and (2) reacting the alpha-tocopherol acid ester obtained in the step (1) with NaOH or KOH to obtain a target product alpha-tocopherol carboxylate, and marking as a compound 2, namely the final product.

In one embodiment of the present invention, the specific synthetic procedure for the compound is as follows:

(1) synthesis of Compound 1: get K₂CO₃Placed in a reaction vessel under N₂Adding α -tocopherol dissolved in aprotic solvent under protection, stirring, adding 2-halogenated acid ethyl ester dissolved in aprotic solvent, heating to 50-70 deg.C, and reacting₂CO₃Filtering to remove the aprotic solvent, extracting with petroleum ether, collecting the organic phase after liquid separation, removing the petroleum ether, and further purifying to obtain a purified compound 1;

(2) synthesis of Compound 2: adding the purified compound 1 into a reaction container, adding ethanol and NaOH/KOH for reaction at 70-95 ℃, standing and cooling the mixture after the reaction is finished, removing supernatant, washing the residual product with acetone/ethanol mixed solution, and drying in vacuum to obtain light yellow solid, namely the final product compound 2.

In one embodiment of the present invention, the aprotic solvent in step (1) is DMF or acetone.

In one embodiment of the present invention, the stirring method in step (1) is: stirring for 15-60 min at room temperature.

In one embodiment of the present invention, whether the reaction in step (1) is completed or not is monitored by TLC.

In one embodiment of the present invention, the aprotic solvent is removed in step (1) by rotary evaporation using a vacuum rotary evaporator under boiling water bath conditions at 0.1 MPa.

In one embodiment of the present invention, the extraction method in step (1) is: extracting with petroleum ether in ice water.

In one embodiment of the present invention, the method for removing petroleum ether in the organic phase in step (1) is to use a vacuum rotary evaporator to rotary evaporate petroleum ether in the organic phase.

In one embodiment of the present invention, the purification method in step (1) is a purification through a 300-400 mesh silica gel chromatography column.

The invention provides a metal cleaning agent which contains the alpha-tocopherol surfactant.

The invention provides a cleaning agent for kitchen supplies, which contains the alpha-tocopherol surfactant.

The invention provides a laundry detergent which contains the alpha-tocopherol surfactant.

The present invention provides a personal care product comprising the above-described alpha-tocopherol surfactant.

[ advantageous effects ]:

(1) the invention takes α -tocopherol as raw material, and obtains a carboxylate surfactant through a series of synthetic steps, wherein the critical micelle concentration of the surfactant at 25 ℃ is 3.89 mmol.L^-1，C₂₀0.27 mmol. multidot.L^-1It shows excellent aggregating ability and high surface tension reducing efficiency. The surfactant has very low foaming and foam stabilizing properties. The initial foam volume is only 0.5ml, the half-life period of the foam is less than 3 seconds, and the foam can be applied to the fields of metal cleaning agents, personal washing and protecting articles and the like.

(2) Meanwhile, the alpha-tocopherol surfactant prepared by the invention is a high-quality surfactant product with good affinity, good biodegradability and low skin irritation. The carboxylate surfactant is widely used due to its advantages of mildness, low irritation, good biocompatibility and the like. Alpha-tocopherol is the most important active compound in vitamin E extracted from natural products, so that the alpha-tocopherol has good biodegradability. The carboxylate surfactant synthesized by using the surfactant as a raw material has the advantages of good biodegradability, good affinity of the carboxylate surfactant and low skin irritation.

Drawings

Fig. 1 is a molecular structure of an α -tocopherol surfactant prepared in example 1.

FIG. 2 is a NMR spectrum of alpha-tocopherol surfactant prepared in example 1.

FIG. 3 is a graph of the surface tension γ of the α -tocopherol surfactant prepared in example 1 as a function of concentration C (25 ℃).

FIG. 4 is a photograph (25 ℃) of foams of various concentrations of the alpha-tocopherol surfactant prepared in example 1.

FIG. 5 shows 4 mmol. L^-1Graph (25 ℃) of the particle size distribution of the α -tocopherol surfactant solution prepared in example 1.

FIG. 6 shows 6 mmol. multidot.L prepared in comparative example 1^-1Photograph of sodium laurate foam (25 ℃).

Detailed Description

Embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention.

[ example 1 ]

Synthesis of compound 1: 7.7g (0.056mol) of K₂CO₃Put into a 250mL three-necked bottle at N₂19.8g (0.046mol) of α -tocopherol in DMF are added thereto under protection, stirred at room temperature for 30min, 9.3g (0.056mol) of ethyl 2-bromoacetate in DMF are added, the temperature is raised to 50 ℃ and the progress of the reaction is monitored by TLC₂CO₃Filtering, removing DMF at 90rad/min with a vacuum rotary evaporator under the condition of 0.1MPa in a boiling water bath, extracting with petroleum ether and ice water, collecting the organic phase after liquid separation, removing the solvent petroleum ether in the organic phase at 85rad/min with a vacuum rotary evaporator at 0.1MPa and 60-70 ℃, and adding the following components in parts by weight: ethyl acetate 10:1 as eluent was purified through a 300-400 mesh silica gel chromatography column.

Synthesis of Compound 2: 16.3g (0.031mol) of purified compound 1 were added to a 250mL single-neck flask, and 80mL of ethanol and 1.22g (0.031mol) of NaOH were added and reacted at 70 ℃. And (3) after the reaction is finished, standing and cooling the mixture, pouring supernatant liquor, washing the product by using an acetone/ethanol solution, and drying in vacuum to obtain a light yellow solid, namely the alpha-tocopherol surfactant. Fig. 1 shows the molecular structure of the α -tocopherol surfactant prepared in this example.

Structure and purity determination of alpha-tocopherol surfactants:

weighing appropriate amount of α -tocopherol, placing in a nuclear magnetic tube, and adding deuterated reagent CDCl₃And (4) dissolving. Using an AduranceIII NMR spectrometer at 25 deg.C¹And (3) performing H NMR (nuclear magnetic resonance) testing,¹the resonance frequency of H was 400MHz, FIG. 2 is the hydrogen nuclear magnetic resonance spectrum of α -tocopherol surfactant prepared in this example, and it can be seen from FIG. 2 that the chemical shift of each hydrogen coincides with that of the target product α -tocopherol, indicating that the final product was obtained.

Measurement of surface tension of alpha-tocopherol surfactant:

respectively prepared into 0.002, 0.003, 0.006, 0.01, 0.02, 0.03, 0.06, 0.1, 0.2, 0.3, 0.6, 1, 2, 3, 6, 10 mmol.L^-1The surface tension of the surfactant aqueous solution with the concentration is measured by a ring-hanging method at 25 ℃, each point is repeated for 3 times, the average value is taken, the change relation curve of the surface tension of the sample along with the concentration is drawn, the corresponding concentration at the turning point is the critical micelle concentration of the surfactant, figure 3 is the surface tension gamma of the α -tocopherol surfactant prepared by the embodiment along with the change curve of the concentration C (25 ℃), as can be seen from figure 3, the critical micelle concentration of the α -tocopherol surfactant at 25 ℃ is 3.89 mmol.L^-1The surface tension of water is reduced by 20mN · m^-1Corresponding to the surfactant concentration (C)₂₀) 0.27 mmol. multidot.L^-1。

Measurement of foam properties of alpha-tocopherol surfactants:

10mL of 2, 4, 6 mmol. multidot.L was prepared^-1An aqueous solution of α -tocopherol surfactant at a concentration was placed in a 100mL stoppered cylinder, shaken vigorously 25 times and allowed to stand, and the lather volume of the surfactant was recorded at 25 ℃ as a function of time.

FIG. 4 is a photograph (25 ℃) of foams of α -tocopherol surfactant of different concentrations prepared in this example, and it can be seen from FIG. 4 that as the concentration increases, the foam height rises from 0 to 0.5mL at 6 mmol.L^-1The foam half-life (the half-life of the foam as the height of the foam drops to the initial height) at the concentration is less than 3 seconds.

4mmol·L^-1α -determination of aggregate particle size in aqueous solutions of tocopherol surfactants:

configuration 4 mmol. L^-1α -aqueous solution of tocopherol surfactant, scanning the particle size distribution of the solution at 25 deg.C with a particle size analyzer, as can be seen from FIG. 4, the solution has opalescence, and FIG. 5 is 4 mmol. L^-1α -tocopherol surfactant solution (25 deg.C), as can be seen from FIG. 5, the particle size of the surfactant is uniformly distributed at 240-250nm, and it is inferred that vesicles around 240nm are formed.

[ example 2 ]

Synthesizing the low-foam facial cleanser:

20 wt% of carborpol941 diluted to 1 wt% is dissolved in 10 wt% of glycerol and then dissolved in 1.2 wt% of alpha-tocopherol surfactant in water to serve as a water phase, and 3 wt% of octadecanol, 1 wt% of beeswax, 2 wt% of polyoxyethylene soyamine (S2), 2 wt% of ceteareth alcohol (S21), 10 wt% of white oil, 2 wt% of squalane and 0.2 wt% of ethylparaben are uniformly mixed to serve as an oil phase. Respectively heating the water phase and the oil phase to 90 ℃, pouring the oil phase into the water phase while stirring, homogenizing for 1min by a homogenizer, slowly cooling in a water bath, adding 0.15 wt% of triethanolamine and the balance of water at 50 ℃, stirring until frosting, and standing to obtain the low-foam facial cleanser with the alpha-tocopherol surfactant as the main effective component.

Measurement of foam performance of the low-foam facial cleanser:

with 150mg/kg CaCl₂Hard water the low foaming facial cleanser was formulated as a 3g/kg dilute solution. Adding 200mL of solution heated to 40 ℃ into a burette of a Roche foam instrument, allowing the solution to flow down along the central line of a graduated burette, starting timing and reading the foam height after the solution flows out, stopping when the foam height is half of the initial height, and repeating3 times. The low-foaming facial cleanser has the initial foam height of 0.5mL and the foam half-life period of less than 1 second.

Comparative example 1

Determination of the foam Properties of sodium laurate:

10mL of 6 mmol. L was prepared^-1The aqueous sodium laurate solution with a concentration is placed in a measuring cylinder with a plug of 100mL, shaken vigorously for 25 times and then left to stand, and the foam volume of the surfactant is recorded at 25 ℃ as a function of time.

FIG. 6 shows 6 mmol. multidot.L of a compound prepared in this comparative example^-1Photograph (25 ℃) of the sodium laurate foam, and as can be seen from FIG. 6, the foam height was 31 ml. At 6 mmol. multidot.L^-1The foam half-life (the half-life of the foam as the height of the foam drops to the initial height) at the concentration was 27 minutes.

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.