One-step emulsification method for preparing Bijels stabilized by amphiphilic random polymer self-assembled aggregate

Abstract

The invention discloses a one-step emulsification method for preparing Bijels stabilized by an amphiphilic random polymer self-assembled aggregate, and belongs to the technical field of emulsion preparation. According to the invention, an amphiphilic random polymer poly (styrene-co-methacrylic acid) (P (St-co-MAA)) is adopted, and self-assembly is realized through pH regulation to form an aggregate; and then taking a P (St-co-MAA) aqueous solution as an aqueous phase, mixing the aqueous phase with the oil phase, and performing high-speed emulsification to obtain the bicontinuous emulsion gel (Bijels). The Bijels disclosed by the invention is good in stability and can be applied to the fields of sustained-release microcapsules, electrochemistry, food processing, functional materials, biological medicines and the like.

Description

Technical Field

[0001] The present invention relates to the preparation of Bijels stabilized by amphiphilic random polymer self-assembled aggregates by a one-step emulsification method, belonging to the technical field of emulsion preparation. Background Art

[0002] Traditional emulsions are composed of two immiscible liquids. One phase of the liquid is dispersed in the continuous phase in the form of droplets by surfactants. The surfactants used usually include low-molecular surfactants, amphiphilic polymer emulsifiers, etc. New emulsions are also called Pickering emulsions, that is, solid particles are used to stabilize the two-phase interface. Compared with traditional emulsions, in addition to having longer storage stability, they have lower toxicity and good biocompatibility. Whether it is a traditional emulsion or a Pickering emulsion, they are all oil-in-water (O / W) emulsions, water-in-oil (W / O) emulsions and multiple emulsions, and these emulsions all contain dispersed droplets. In some special cases, if both immiscible fluids exist in the form of continuous phases and there is no dispersed phase, and the two phases are arranged in a bicontinuous manner and cross each other, and solid particles or surfactants block at the liquid-liquid interface to stabilize the system, the emulsion formed at this time is called a bicontinuous emulsion, and it is always called a bicontinuous emulsion gel (Bijels) because it exhibits gel characteristics. Due to the fact that the emulsifier has both positive and negative curvatures at the two-phase interface, Bijels not only exhibits efficient and continuous mass transfer and supply in the oil phase and the water phase, but also provides an ideal platform for applications that rely on two-phase interface transport, such as battery electrodes, heterogeneous catalysis, filtration membranes, and chemical reactors, etc.

[0003] Initially, the bicontinuous emulsion channels were realized by thermal quenching, solvent transfer and vaporization-induced phase separation of two immiscible liquids. Thermal quenching-induced phase separation requires precise temperature control, while the other two methods both require the participation of co-solvents. During the phase separation process, the interfacial tension increases with the increase of the composition difference between the two phases, prompting the colloidal particles to transfer from one phase to the two-phase interface to form a rigid blocking layer. Subsequently, when the phase separation ends, a Pickering emulsion with a special structure (the oil and water phases penetrate and cross each other) can be obtained.

[0004] Currently, Bijels can be prepared by direct mixing, including two-step mixing and one-step mixing. Dongyu Cai (Cai D, Clegg P S, Li T, et al. Bijels formed by direct mixing[J]. Soft matter, 2017, 13(28):4824-4829.) et al. prepared Bijels by mixing glycerol and silicone oil through two-step mixing: cetyltrimethylammonium bromide (CTAB) was dissolved in glycerol containing silica nanoparticles to complete the combination of particles and surfactants to achieve the modification of particle emulsifiers, a certain volume of mixed-viscosity silicone oil was added and slow stirring was completed using a magnetic stir bar to obtain glycerol droplets, and then vigorous mixing was carried out to shear the droplets to generate additional interfaces, and the nanoparticles were blocked at the interfaces to form a bicontinuous structure. Caili Huang (Huang C, Forth J, Wang W, et al. Bicontinuous structured liquids with sub-micrometre domains using nanoparticle surfactants[J]. Nature nanotechnology, 2017, 12(11):1060-1063.) et al. used SiO2 combined with hydrophilic carboxylic acid-functionalized polystyrene (PS-CO2H) and hydrophobic amine-functionalized polydimethylsiloxane (PDMS-NH2) to stabilize the water-toluene interface, and successfully prepared Bijels with sub-micron size by homogenization.

[0005] It can be seen that the preparation method of Bijels has been greatly optimized. However, when preparing Bijels, most choose particle emulsifiers such as SiO2, Janus, and nanocrystals as stabilizers for the two-phase interface, and their surfaces need to be appropriately modified to adjust their wettability, including covalently connecting hydrophobic or hydrophilic groups or physically adsorbing anionic and cationic surfactants, multivalent ions, or polyelectrolytes. The hydrophilicity and hydrophobicity of particle emulsifiers are reflected by the three-phase contact angle θ at the two-phase interface; when θ < 90°, the particles are more hydrophilic and easily form O / W emulsions; when θ > 90°, W / O emulsions are easily formed; when θ is near 90°, the particles show the same wettability in the two-phase liquid, generating zero curvature and bicontinuous liquid regions to form bicontinuous emulsions. However, the successful preparation of Bijels requires careful modification of the particle surface to adjust its wettability, which increases the complexity of the Bijels preparation process.

[0006] Currently, although there are relevant reports on the preparation of bicontinuous emulsions by one-step mixing method, no relevant reports on using amphiphilic polymers as stabilizers for the oil-water interface to prepare Bijels have been found. Summary of the Invention

[0007] [Technical Problem]

[0008] When preparing Bijels, most choose particulate emulsifiers such as SiO2, Janus, nanocrystals, etc. as stabilizers for the two-phase interface, and the surface of the particles needs to be carefully modified to adjust their wettability, with complex operations;

[0009] Currently, there is no relevant report on using amphiphilic polymers as stabilizers for the oil-water interface to prepare Bijels.

[0010] [Technical Solution]

[0011] To solve the above problems, the present invention uses an amphiphilic random polymer poly(styrene-co-methacrylic acid) (P(St-co-MAA)), which forms aggregates through self-assembly by adjusting the pH; then, an aqueous solution of P(St-co-MAA) is used as the aqueous phase and mixed with the oil phase for high-speed emulsification to obtain bicontinuous emulsion gels (Bijels). The Bijels of the present invention have good stability and can be used in fields such as sustained-release microcapsules, electrochemistry, food processing, functional materials, and biomedicine.

[0012] The first object of the present invention is to provide a method for preparing Bijels stabilized by self-assembled aggregates of amphiphilic random polymers by a one-step emulsification method, comprising the following steps:

[0013] Adjust the pH of the aqueous solution of P(St-co-MAA) to 6.6 - 8.4 to obtain the aqueous phase; mix the aqueous phase and the oil phase and perform high-speed emulsification to obtain Bijels.

[0014] In one embodiment of the present invention, the concentration of the aqueous solution of P(St-co-MAA) is 0.5 - 1.5% (w / v, g / 100 mL), and further preferably 1% (w / v, g / 100 mL).

[0015] In one embodiment of the present invention, the aqueous solution of P(St-co-MAA) is prepared by dissolving P(St-co-MAA) in a NaOH solution, and the NaOH solution is an aqueous NaOH solution with a concentration of 0.1 mol / L.

[0016] In one embodiment of the present invention, P(St-co-MAA) was prepared according to the reference (Zhang Y, Du H, Wang Y, et al. pH-regulated self-assembly of poly(styrene-co-methacrylic acid) for fabrication of pH-responsive Pickering emulsion[J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2025: 136231.).

[0017] In one embodiment of the present invention, the pH of the P(St-co-MAA) aqueous solution is adjusted to 7.0 - 8.0.

[0018] In one embodiment of the present invention, the oil phase is one or more of high-viscosity silicone oil, glyceryl trioctanoate (GTCC), and paraffin; the viscosity range of the high-viscosity silicone oil is 50 cst - 100 cst.

[0019] In one embodiment of the present invention, when the oil phase is paraffin, the aqueous phase needs to be heat-treated at 55 - 65 °C for 20 - 40 min; the oil phase needs to be melted, and the general melting temperature is 65 - 85 °C.

[0020] In one embodiment of the present invention, the mass ratio of the oil phase to the aqueous phase is 6 - 7:3 - 4.

[0021] In one embodiment of the present invention, high-speed emulsification is carried out at 8000 - 10000 rpm for 1 - 2 min.

[0022] The second object of the present invention is the Bijels prepared by the method described in the present invention.

[0023] The third object of the present invention is the application of the Bijels described in the present invention in the fields of sustained-release microcapsules, electrochemistry, food processing, functional materials, biomedicine, etc.

[0024] [Beneficial effects]

[0025] (1) The double-continuous emulsion gel prepared in the present invention can be stable at room temperature, which indicates that the Bijels obtained by pH regulation have certain stability.

[0026] (2) The present invention does not require a combination of a particulate emulsifier and a functional polymer with complementary functions as a stabilizer at the two-phase interface of Bijels, nor does it require careful surface modification of the particulate emulsifier to adjust its wettability.

[0027] (3) The Bijels prepared by the present invention only need to use amphiphilic polymer self-assembled aggregates as stabilizers at the liquid-liquid interface, and the wettability can be regulated by adjusting the pH.

[0028] (4) The regulation of the bicontinuous emulsion channels prepared by the present invention can be achieved only by adjusting the pH value of the polymer aqueous solution, and the scheme is simple and easy to implement. Description of the Drawings

[0029] Figure 1 Photographs (a) of emulsions with different pH values after staining and photographs (b) after inversion.

[0030] Figure 2 Fluorescence magnified photographs of emulsions with different pH values taken with a 10× objective lens and a fluorescence overall photograph of the pH 7.3 emulsion taken with a 4× objective lens.

[0031] Figure 3 Two-dimensional (a) and three-dimensional (b) scanning images of the emulsion prepared at pH 7.3 (Example 1) taken at an excitation wavelength of 525 nm with a laser confocal microscope and three-dimensional (c) scanning image taken at an excitation wavelength of 285 nm.

[0032] Figure 4 Results of viscosity test (a) and modulus test (b) of emulsions with different pH values.

[0033] Figure 5 Inverted photographs (a) of the emulsion prepared at pH 7.3 (Example 1) placed in the dark at room temperature for 1 day and 7 days and fluorescence microscope images (b) corresponding to the number of days.

[0034] Figure 6 Fluorescence overall photographs (a) and fluorescence magnified photographs (b) of emulsions prepared at different pH values.

[0035] Figure 7 Polarizing microscope photographs of emulsions with different pH values.

[0036] Figure 8 SEM photographs of emulsions with different pH values taken after freeze-drying.

[0037] Figure 9 Fluorescence overall photograph of the emulsion prepared in Example 4.

[0038] Figure 10 Fluorescence overall photograph of the emulsion prepared in Example 5; among them, (a) is 50 cst; (b) is 100 cst.

[0039] Figure 11 Fluorescence overall photograph of the emulsion prepared in Comparative Example 5.

[0040] Figure 12 Fluorescence overall photograph of the emulsion prepared in Comparative Example 6.

[0041] Figure 13 Fluorescence overall photograph of the emulsion prepared in Comparative Example 7. Detailed implementation manners

[0042] The preferred embodiments of the present invention are described below. It should be understood that the embodiments are for better explaining the present invention and are not used to limit the present invention.

[0043] Testing methods:

[0044] 1. Emulsion staining:

[0045] Mix the polymer aqueous solution stained with FITC and GTCC stained with Nile red.

[0046] 2. Appearance observation:

[0047] Take a photo of the emulsion and observe the appearance such as phase separation and color of the emulsion to roughly judge the type of emulsion. Invert the sample bottle containing the emulsion and observe whether the sample has fluidity.

[0048] 3. Fluorescence microscopy characterization:

[0049] Take an appropriate amount of the emulsion on a glass slide and observe the emulsion structure using a fluorescence microscope at an excitation wavelength of 485 nm. Take fluorescence microscope images of the emulsion using 4× and 10× objective lenses.

[0050] 4. Laser confocal microscopy imaging:

[0051] Take 100 μL of the emulsion in a confocal Petri dish with a glass slide diameter of 20 mm, place it under a laser confocal microscope with an objective lens of 10×, a resolution of 512×512, a scanning speed of 600 Hz, and excitation wavelengths of 525 nm and 485 nm to observe the emulsion, and take two-dimensional and three-dimensional images of the emulsion under the conditions of a resolution of 1024×1024 and a scanning speed of 200 Hz.

[0052] 3. Rheological analysis:

[0053] After the emulsion is placed at room temperature for 1 day, take an appropriate amount of the sample on the test bench of a rotational rheometer, select a cone-plate mold with a diameter of 40 mm, keep the temperature constant at 25°C, and test the change in the apparent viscosity of the sample during the increasing process of the shear rate (0.1 - 100 s -1 ).

[0054] Moreover, modulus tests were carried out on samples with pH values of 6.6 and 7.3, that is: using a cone-plate mold with a diameter of 40 mm, frequency sweep tests were carried out on the samples under the condition of a frequency of 0.1 rad / s to 100 rad / s to obtain the corresponding storage modulus G' and loss modulus G", and the two were compared to judge whether the gel structure was formed.

[0055] 4. Stability test:

[0056] The emulsion was placed in the dark at room temperature for 1 d and 7 d, and the sample was inverted to observe whether the emulsion had fluidity to judge whether its gel properties disappeared, so as to judge its stability, and it was verified by fluorescence microscopy.

[0057] 5. Hot stage polarized light microscope photography:

[0058] The emulsion was observed and photographed under 5× and 10× objective lenses through a hot stage polarized light microscope.

[0059] 6. Scanning electron microscopy characterization:

[0060] The remaining emulsion after photographing with the hot stage polarized light microscope was freeze-dried to obtain a powder sample. An appropriate amount of the sample was placed on the conductive adhesive, and after gold spraying, it was characterized by a field emission scanning electron microscope at an acceleration voltage of 3.0 kV.

[0061] Raw materials used in the examples:

[0062] Glycerol caprylate / caprate (GTCC, 98%): Purchased from Shandong Yousuo Chemical Technology Co., Ltd.;

[0063] Nile red (BR): Purchased from Shanghai Titan Scientific Co., Ltd.;

[0064] Fluorescein isothiocyanate (FITC, 90%): Purchased from Shanghai Merck Chemical Technology Co., Ltd.;

[0065] Sodium hydroxide (NaOH, AR), hydrochloric acid (HCl, AR): Purchased from Sinopharm Chemical Reagent Co., Ltd.;

[0066] Solid paraffin: Purchased from Nantong Haizhixing Experimental Equipment Co., Ltd.;

[0067] P(St-co-MAA) (monomer ratio 6:4, Mn = 9655, Mw = 13942): Prepared according to the reference (Zhang Y, Du H, Wang Y, et al. pH-regulated self-assembly of poly(styrene-co-methacrylic acid) for fabrication of pH-responsive Pickering emulsion[J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2025:136231.).

[0068] In the examples, the solution without specifically indicating the solvent uses water as the solvent, and the concentration unit % without specifically indicating the meaning refers to g / 100mL.

[0069] Example 1

[0070] A method for preparing Bijels stabilized by amphiphilic random polymer self-assembled aggregates by a one-step emulsification method, comprising the following steps:

[0071] Mix P(St-co-MAA) with 0.1 mol / L aqueous NaOH solution and stir overnight to obtain an aqueous polymer solution with a concentration of 1.0% (w / v);

[0072] Adjust the pH of the P(St-co-MAA) aqueous solution to 7.3 to obtain the aqueous phase; use glyceryl caprylate as the oil phase, mix the aqueous phase and the oil phase according to a mass ratio of 4:6, and emulsify at high speed at 10000 rpm for 2 min to obtain Bijels.

[0073] Comparative Example 1

[0074] Adjust the pH of the P(St-co-MAA) aqueous solution in Example 1 to 6.5, and keep other conditions the same as in Example 1 to obtain an emulsion.

[0075] Comparative Example 2

[0076] Adjust the pH of the P(St-co-MAA) aqueous solution in Example 1 to 8.5, and keep other conditions the same as in Example 1 to obtain an emulsion.

[0077] Perform performance tests on the emulsions obtained in Example 1 and Comparative Examples 1 and 2, and the test results are as follows:

[0078] Figure 1 Photographs (a) after staining and photographs (b) after inversion of emulsions with different pH values. From Figure 1It can be seen that: compared with the emulsions at pH 6.5 and 7.3, the emulsion layer at pH 8.5 is located at the top, and obvious green aqueous phase precipitates at the bottom, indicating that the emulsion type has changed significantly with the change of pH. There are obvious differences in the colors of the emulsions at pH 6.5 and 7.3: compared with the orange color of the emulsion at pH 7.3, the emulsion at pH 6.5 shows a pink effect. Since the oil phase GTCC shows a red effect after being stained with Nile red and the aqueous phase is green after being stained with FITC, at pH 6.5, the oil phase stained with Nile red is the continuous phase of the emulsion, and the dispersed aqueous phase is encapsulated by the oil phase in the form of droplets, and the emulsion shows the color of the continuous phase. Therefore, the emulsion is of the W / O type at pH 6.5. The emulsion at pH 7.3 is orange, which may be because the continuous phase is not a single phase but a mixture of the aqueous phase and the oil phase under this pH condition, and the two penetrate each other to form a unique bicontinuous structure. Therefore, the emulsion at pH 7.3 shows a mixed color of red and green. The three emulsions were inverted to observe their fluidity and the inverted photos of the emulsions were obtained. Only the emulsion at pH 8.5 has fluidity, while the emulsions at pH 6.5 and 7.3 are located at the bottom of the sample bottle before and after inversion and do not have fluidity, indicating that both of these emulsions contain a three-dimensional gel network structure, which can show that the emulsion at pH 7.3 has the properties of a bicontinuous gel.

[0079] Figure 2 Fluorescence magnified photos of emulsions at different pH values were taken using a 10× objective lens and a fluorescence overall photo of the emulsion at pH 7.3 was taken using a 4× objective lens. From Figure 2 It can be seen that: at pH 8.5, the continuous phase is green and the dispersed phase is red, so the obtained emulsion is of the O / W type; the emulsion at pH 6.5 is of the W / O type; the emulsion at pH 7.3 is a bicontinuous emulsion, changing from the spherical shape and anisotropy of the droplets of the emulsion at pH 8.5 to the interconnection between droplets, and forming continuous oil regions, water regions or being connected together or blocked by continuous oil regions.

[0080] Figure 3 Two-dimensional (a) and three-dimensional (b) scanning images of the emulsion prepared at pH 7.3 (Example 1) taken at an excitation wavelength of 525 nm and three-dimensional (c) scanning image taken at an excitation wavelength of 285 nm by a laser confocal microscope. From Figure 3 It can be seen from (a) that: although there are also some small black regions in the red regions, most of them are the interpenetration of red and black regions, that is, the interpenetrating arrangement of the oil phase and the aqueous phase (the red regions represent the oil phase and the black regions represent the aqueous phase); from Figure 3 It can be seen from (b) that: the oil phases (red regions) between different axial planes are connected together, and the aqueous phases (depressions) are either connected together or blocked by the oil phase; from Figure 3It can be seen from (c) that the aqueous phase (green area) and the oil phase (gray area) are either connected to each other or blocked by the other. That is, it shows the formation of the bicontinuous structure of the emulsion.

[0081] Figure 4 Results of viscosity test (a) and modulus test (b) for emulsions with different pH values. From Figure 4 It can be seen from (a) that as the shear rate increases, the apparent viscosities of the three emulsions all gradually decrease and then tend to be flat, showing obvious shear thinning behavior. At lower shear rates, the viscosities of the three emulsions are as follows: the viscosity of the bicontinuous emulsion is the largest, followed by W / O, and the viscosity of O / W is the smallest. From Figure 4 It can be seen from (b) that the bicontinuous emulsion at pH 7.3 shows the result of storage modulus (G') > loss modulus (G") in the modulus test, indicating that an elastic gel network structure is formed in the emulsion under this pH condition, and a bicontinuous emulsion gel (Bijels) is obtained. The W / O emulsion at pH 6.6 also shows G' > G", indicating that the Pickering W / O emulsion stabilized by self-assembled aggregates can also form a gel network structure under certain conditions.

[0082] Figure 5 Photographs of the inverted emulsions (a) and fluorescence microscopy images (b) of the emulsions (Example 1) prepared at pH 7.3 after being placed in the dark at room temperature for 1 day and 7 days. From Figure 5 It can be seen that after the emulsion is placed for 1 day and 7 days, its state does not change significantly. After inversion, it is located at the bottom of the sample bottle, showing its original gel properties. This shows that Bijels has a certain stability. After the emulsion is placed for 7 days, its structure does not change significantly. This shows that the gel properties and microstructure of Bijels do not change significantly with time, showing a certain stability.

[0083] Example 2

[0084] Adjust the pH of the P(St-co-MAA) aqueous solution in Example 1 to 7.1, 7.6, and 7.9, and keep the others the same as in Example 1 to obtain emulsions.

[0085] Perform performance tests on the obtained emulsions, and the test results are as follows:

[0086] Figure 6 Overall fluorescence photographs (a) and magnified fluorescence photographs (b) of the emulsions prepared at different pH values. From Figure 6It can be seen that the microstructure of the emulsion is similar to that of the emulsion at pH 7.3, both of which are the interconnection between the aqueous phases, the interconnection between the oil phases, and the interpenetration and intersection between the oil and water phases. The bicontinuous emulsion channels (continuous channels formed by the intercrossing of the aqueous phase and the oil phase) at different pH values show obvious size changes with the change of pH, that is, the bicontinuous channels become more regular and compact with the decrease of pH.

[0087] Example 3

[0088] A method for preparing Bijels stabilized by amphiphilic random polymer self-assembled aggregates by a one-step emulsification method, comprising the following steps:

[0089] Mix P(St-co-MAA) and 0.1 mol / L aqueous NaOH solution, stir overnight to obtain a 1.0% (w / v) polymer aqueous solution;

[0090] Treat the P(St-co-MAA) aqueous solution at 60 °C for 30 min and adjust the pH to 7.2 to obtain the aqueous phase; use paraffin melted at 80 °C as the oil phase, mix the aqueous phase and the oil phase according to a mass ratio of 4:6, and emulsify at high speed at 10000 rpm for 2 min to obtain Bijels.

[0091] Comparative Example 3

[0092] Adjust the pH of the P(St-co-MAA) aqueous solution in Example 3 to 6.4, and keep the others the same as in Example 3 to obtain an emulsion.

[0093] Comparative Example 4

[0094] Adjust the pH of the P(St-co-MAA) aqueous solution in Example 3 to 8.7, and keep the others the same as in Example 3 to obtain an emulsion.

[0095] Perform performance tests on the emulsions obtained in Example 3 and Comparative Examples 3 and 4, and the test results are as follows:

[0096] Figure 7 Are polarized light microscope photos of emulsions at different pH values. From Figure 7 It can be seen that when the pH value is 6.4 and 8.7, there are obvious droplets in the pictures; while when the pH is 7.2, there are only a small number of droplets in the pictures, and most of them are the intercrossing of dark and light regions, which are bicontinuous emulsions; W / O and O / W emulsions are obtained at pH 6.4 and 8.7.

[0097] Figure 8 Are SEM photos taken after freeze-drying of emulsions at different pH values. From Figure 8It can be seen that: in the SEM image, the gray area is the oil region, and the black area is the water region after freeze-drying treatment. When the pH is 8.7, due to the characteristic that the paraffin morphology of the oil phase changes with temperature, the oil phase presents a non-spherical shape different from the past as the dispersed phase, forming an O / W emulsion; when the pH is 7.2, the oil droplets coalesce to form a continuous oil phase, which together with the water phase becomes the continuous phase of the system; when the pH is 6.4, the formed emulsion is W / O, and at this time the continuous phase of the emulsion is the oil phase, and only the continuous phase of the emulsion can be photographed in the SEM.

[0098] Example 4

[0099] In Example 1, the water phase and the oil phase were mixed according to a mass ratio of 3:7, and the rest was kept the same as in Example 1 to obtain an emulsion.

[0100] The obtained emulsion was subjected to performance tests, and the test results are as follows:

[0101] The emulsion is a bicontinuous emulsion ( Figure 9 ).

[0102] Example 5

[0103] In Example 1, the oil phase was adjusted to silicone oil (50 cst, 100 cst), and the rest was kept the same as in Example 1 to obtain an emulsion.

[0104] The obtained emulsion was subjected to performance tests, and the test results are as follows:

[0105] The emulsion is a bicontinuous emulsion ( Figure 10 ).

[0106] Comparative Example 5

[0107] In Example 1, the oil phase was adjusted to silicone oil with a viscosity of 10 cst, and the rest was kept the same as in Example 1 to obtain an emulsion.

[0108] The obtained emulsion was subjected to performance tests, and the test results are as follows:

[0109] A bicontinuous emulsion could not be formed, and the emulsion at this time was O / W ( Figure 11 ).

[0110] Comparative Example 6

[0111] In Example 1, the water phase and the oil phase were mixed according to a mass ratio of 2:8, and the rest was kept the same as in Example 1 to obtain an emulsion.

[0112] The obtained emulsion was subjected to performance tests, and the test results are as follows:

[0113] A bicontinuous emulsion could not be formed ( Figure 12 ).

[0114] Comparative Example 7

[0115] In Example 1, the aqueous phase and the oil phase were mixed in a mass ratio of 5:5, and the others were kept the same as in Example 1 to obtain an emulsion.

[0116] The obtained emulsion was subjected to performance tests, and the test results are as follows:

[0117] Unable to form a continuous emulsion ( Figure 13 ).

[0118] Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be defined by the claims.

Claims

1. A method for preparing Bijels stabilized by amphiphilic random polymer self-assembled aggregates by a one-step emulsification method, characterized in that, The method comprises the following steps: Adjust the pH of the aqueous solution of P(St-co-MAA) to 6.6 - 8.4 to obtain an aqueous phase; mix the aqueous phase and an oil phase and perform high-speed emulsification to obtain Bijels.

2. The method according to claim 1, wherein The concentration of the aqueous solution of P(St-co-MAA) is 0.5 - 1.5%.

3. The method according to claim 1, wherein Adjust the pH of the aqueous solution of P(St-co-MAA) to 7.0 - 8.

0.

4. The method according to claim 1, wherein The mass ratio of the oil phase to the aqueous phase is 6 - 7:3 - 4.

5. The method according to claim 1, wherein The oil phase is one or more of high-viscosity silicone oil, glyceryl caprylate / caprate (GTCC), and paraffin; the viscosity range of the high-viscosity silicone oil is 50 cst - 100 cst.

6. The method according to claim 1, wherein The high-speed emulsification is carried out at 8000 - 10000 rpm for 1 - 2 min.

7. The method according to claim 1, characterized in that The aqueous solution of P(St-co-MAA) is prepared by dissolving P(St-co-MAA) in an NaOH solution, and the NaOH solution is an aqueous NaOH solution with a concentration of 0.1 mol / L.

8. The method according to claim 1, wherein When the oil phase is paraffin, the aqueous phase needs to be heat-treated at 55 - 65 °C for 20 - 40 min.

9. Bijels prepared by the method according to any one of claims 1 - 8.

10. Applications of the Bijels according to claim 9 in the fields of sustained-release microcapsules, electrochemistry, food processing, functional materials, biomedicine, etc.

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