Method for preparing Pickering emulsion with uniform size by using dry water powder

Abstract

The invention relates to a method for preparing Pickering emulsion with uniform size by using dry water powder, which comprises the following steps of: mixing hydrophobic polymer particles and a hydrophilic polymer solution, stirring at the speed of not less than 15000 rpm to carry out hydrophilic modification on the surfaces of the hydrophobic particles, then washing and drying to obtain modified hydrophobic particles, and drying to obtain the Pickering emulsion with uniform size. The coverage rate of the hydrophilic polymer on the surfaces of the particles is 5-20%; then, the modified hydrophobic particles and water are mechanically stirred at the speed not smaller than 13000rpm, dry water powder is prepared, and the particle size of the dry water powder is controlled through screening; and finally, dispersing the screened dry water powder into an organic solvent to form the Pickering emulsion with uniform and stable size. The method is simple in process and easy to operate, has relatively strong operability and industrial application prospect, and particularly has important application potential in the fields of chemical industry, pharmacy, food processing and the like.

Description

Technical Field

[0001] The invention relates to the technical field of emulsion preparation, in particular to a method for preparing Pickering emulsion with uniform size by using dry water powder. Background Art

[0002] Pickering emulsion is an emulsion system stabilized by solid particles. Compared with traditional emulsions that rely on surfactants for stabilization, it has unique advantages. Since solid particles can form a physical barrier at the oil-water interface, they can significantly improve the stability of the emulsion. Pickering emulsion has been widely used in the fields of chemical industry, pharmaceuticals, food processing, cosmetics and biotechnology.

[0003] However, the actual preparation process of Pickering emulsion still faces many challenges, which limits its industrial promotion:

[0004] First, the relationship between the droplet size and preparation conditions of Pickering emulsions is complex. The droplet size is affected by many factors, including the type of solid particles, surface properties, particle size, concentration, oil-water ratio, and emulsification conditions (such as stirring speed and time). The lack of clear quantitative rules between these factors makes it difficult to keep the droplet size consistent under different experimental conditions, resulting in poor repeatability of Pickering emulsion performance.

[0005] Secondly, the existing Pickering emulsion preparation method has deficiencies in terms of particle dispersion uniformity and droplet size controllability. Solid particles need good dispersibility and appropriate surface properties to effectively adsorb on the droplet surface and provide stability. However, in actual operation, the dispersion efficiency and adsorption effect of particles are difficult to control, especially in high-concentration particles or complex emulsification systems, which can easily lead to emulsion instability or uneven particle size distribution.

[0006] In addition, traditional emulsification processes often rely on complex equipment and sophisticated experimental conditions, such as high-shear emulsification equipment or multi-stage emulsification operations. This not only increases the difficulty and cost of the preparation process, but also limits the feasibility of Pickering emulsions in large-scale production. Especially for industrial applications, the current method is difficult to simultaneously meet the requirements of emulsion stability, droplet size controllability and process simplicity, further hindering the widespread application of Pickering emulsions.

[0007] Therefore, developing a simple, efficient method that can achieve precise control of droplet size has become an urgent problem to be solved in the field of Pickering emulsion technology. This will not only help improve the repeatability and consistency of the emulsion, but also provide reliable technical support for the industrial promotion of Pickering emulsion. Summary of the invention

[0008] The invention relates to a method for preparing a Pickering emulsion with uniform size by using dry gouache. By modifying hydrophobic particles and accurately controlling the size of the dry gouache, the stability and particle size uniformity of the Pickering emulsion are significantly improved, while the process steps are simplified and the industrial application potential is enhanced.

[0009] Specifically, the present invention provides a method for preparing Pickering emulsion with uniform size using dry gouache, the steps of which are as follows:

[0010] Step 1, homogenizing and mixing the hydrophobic polymer particles and the hydrophilic polymer solution at a speed of not less than 15,000 rpm for 5 minutes or more, filtering and washing with deionized water after mixing, and then drying at 30-50° C. to obtain modified hydrophobic particles;

[0011] Step 2, mechanically stirring the modified hydrophobic particles obtained in step 1 with water at a speed of not less than 13,000 rpm for 30 seconds or more to prepare dry water powder, and sieving the obtained dry water powder;

[0012] Step 3: Disperse the dry water powder obtained after sieving in step 2 into an organic solvent to form a Pickering emulsion.

[0013] Preferably, the hydrophobic polymer in step 1 includes at least one of a fluorocarbon polymer, a hydrocarbon polymer, a silicon-containing polymer, a carbonic acid-containing polymer, an aromatic polymer, a chlorine-containing polymer or a sulfur-containing polymer. Further preferably, the fluorocarbon polymer includes at least one of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF) or ethylene-tetrafluoroethylene copolymer (ETFE);

[0014] And / or, the hydrocarbon polymer includes at least one of polystyrene (PS), polypropylene (PP), polyethylene (PE) or polymethyl methacrylate (PMMA);

[0015] And / or, the silicon-containing polymer includes at least one of polydimethylsiloxane (PDMS) or methyl silicone resin;

[0016] And / or, the carbonic acid group-containing polymer includes at least one of polycarbonate (PC) or polyether carbonate (PEC);

[0017] And / or, the aromatic polymer includes at least one of polyethylene terephthalate (PET) or polyimide (PI);

[0018] And / or, the chlorine-containing polymer includes at least one of polyvinyl chloride (PVC) or chlorinated polyethylene (CPE);

[0019] And / or, the sulfur-containing polymer includes at least one of polyphenylene sulfide (PPS) or vulcanized rubber.

[0020] Preferably, the hydrophilic polymer in step 1 comprises at least one of anionic polymers, cationic polymers or nonionic polymers. Further preferably, the anionic polymer comprises at least one of polyacrylic acid (PAA), sodium polystyrene sulfonate (PSS), sodium carboxymethyl cellulose (CMC-Na), sodium alginate (SA), polyacrylic acid sodium salt (PAANa) or polyvinyl sulfonate (PVS);

[0021] and / or, the cationic polymer comprises at least one of polydiallyldimethylammonium chloride (PDADMAC), polyethyleneimine (PEI), chitosan and its derivatives or polydimethyldiallylammonium chloride (PDMC);

[0022] And / or, the nonionic polymer includes at least one of polyvinyl alcohol (PVA), polyethylene glycol (PEG), polyvinyl pyrrolidone (PVP), polyacrylamide (PAM), hydroxypropyl methylcellulose (HPMC) or methylcellulose (MC);

[0023] And / or, the concentration of the hydrophilic polymer solution is 0.1-2 mg / mL.

[0024] Preferably, the hydrophilic polymer solution in step 1 contains salt. Further preferably, the salt includes sodium chloride (NaCl), and the concentration of the salt solution is 0 to 1 mg / mL.

[0025] Preferably, the solid-to-liquid ratio of the hydrophobic polymer particles to the hydrophilic polymer solution in step 1 is (0.01-0.1) g / mL.

[0026] Preferably, the coverage rate of the hydrophilic polymer on the surface of the hydrophobic polymer particles in step 1 is 5% to 20%.

[0027] Preferably, the solid-to-liquid mass ratio of the modified hydrophobic particles to water in step 2 is 0.1 to 1.

[0028] Preferably, the sieving size described in step 2 is 45±15μm, 69±21μm, 90±25μm, 120±30μm, 150±35μm, 190±40μm, 305±75μm or 440±60μm.

[0029] Preferably, the organic solvent in step 3 comprises at least one of toluene, petroleum ether, methyl tert-butyl ether, n-hexane, cyclohexane, hexadecane, 2-methyltetrahydrofuran, ethyl acetate, benzene, ethanol, acetone or dimethyl sulfoxide.

[0030] Preferably, the solid-to-liquid ratio of the dry water powder to the organic solvent in step 3 is 1:5 to 1:20 g / mL.

[0031] The present invention can achieve the following technical effects:

[0032] (1) The precise control of the Pickering emulsion droplet size was achieved by modifying the hydrophobic particles and controlling the particle size of the dry water powder.

[0033] (2) The prepared Pickering emulsion has high particle size uniformity and stability. DETAILED DESCRIPTION

[0034] Embodiments of the present invention are described in detail below. The embodiments are exemplary and intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0035] Example 1

[0036] Step 1: Add 1g of polytetrafluoroethylene (PTFE) particles to 100mL of an aqueous solution containing 0.1mg / mL polyacrylic acid (PAA) and 1mg / mL sodium chloride, and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PTFE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polytetrafluoroethylene. According to the contact angle data analysis, the coverage of PAA on the particle surface is 10%.

[0037] Step 2: 5 g of the modified polytetrafluoroethylene particles prepared above were added to 50 mL of deionized water, and stirred at 13,000 rpm for 3 min in a mechanical stirrer to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 120 ± 30 μm.

[0038] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of toluene to prepare a Pickering emulsion with uniform particle size.

[0039] The average particle size of the Pickering emulsion prepared in this embodiment is 120 μm, the particle size distribution range is 90-150 μm, and the Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0040] Example 2

[0041] Step 1: Add 1g of polytetrafluoroethylene (PTFE) particles to 10mL of an aqueous solution containing 2mg / mL polyacrylic acid (PAA) and 0.5mg / mL sodium chloride, and stir at 25,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PTFE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 30°C for 12h to obtain modified polytetrafluoroethylene. According to the contact angle data analysis, the coverage of PAA on the particle surface is 20%.

[0042] Step 2: 20 g of the modified polytetrafluoroethylene particles prepared above were added to 20 mL of deionized water, and stirred at 13,000 rpm in a mechanical stirrer for 3 min to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 69±21 μm.

[0043] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of toluene to prepare a Pickering emulsion with uniform particle size.

[0044] The average particle size of the Pickering emulsion prepared in this embodiment is 60 μm, and the particle size distribution range is 48-90 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0045] Example 3

[0046] Step 1: Add 0.1g of polytetrafluoroethylene (PTFE) particles to 100mL of an aqueous solution containing 0.1mg / mL polyacrylic acid (PAA), and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PTFE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polytetrafluoroethylene. According to the contact angle data analysis, the coverage of PAA on the particle surface is 5%.

[0047] Step 2: 5 g of the modified polytetrafluoroethylene particles prepared above were added to 50 mL of deionized water and stirred at 13,000 rpm for 30 seconds in a mechanical stirrer to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 120 ± 30 μm.

[0048] Step 3: Take 1 g of the sieved dry water powder and disperse it in 5 mL of hexadecane to prepare a Pickering emulsion with uniform particle size.

[0049] The average particle size of the Pickering emulsion prepared in this embodiment is 100 μm, and the particle size distribution range is 90-150 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0050] Example 4

[0051] Step 1: Add 1g of polytetrafluoroethylene (PTFE) particles to 100mL of an aqueous solution containing 1mg / mL polyvinyl alcohol (PVA) and 1mg / mL sodium chloride, and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PTFE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polytetrafluoroethylene. According to the contact angle data analysis, the coverage of PVA on the particle surface is 13%.

[0052] Step 2: 10 g of the modified polytetrafluoroethylene particles prepared above were added to 50 mL of deionized water, and stirred at 13,000 rpm in a mechanical stirrer for 3 min to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 120 ± 30 μm.

[0053] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of toluene to prepare a Pickering emulsion with uniform particle size.

[0054] The average particle size of the Pickering emulsion prepared in this embodiment is 120 μm, and the particle size distribution range is 90-150 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0055] Example 5

[0056] Step 1: Add 1g of polytetrafluoroethylene (PTFE) particles to 100mL of an aqueous solution containing 2mg / mL polyvinyl alcohol (PVA) and 1mg / mL sodium chloride, and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PTFE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polytetrafluoroethylene. According to the contact angle data analysis, the coverage of PVA on the particle surface is 20%.

[0057] Step 2: 10 g of the modified polytetrafluoroethylene particles prepared above were added to 10 mL of deionized water and stirred at 13,000 rpm for 30 seconds in a mechanical stirrer to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 69 ± 21 μm.

[0058] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of petroleum ether to prepare a Pickering emulsion with uniform particle size.

[0059] The average particle size of the Pickering emulsion prepared in this embodiment is 60 μm, and the particle size distribution range is 48-90 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 24 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0060] Example 6

[0061] Step 1: Add 1g of polytetrafluoroethylene (PTFE) particles to 100mL of an aqueous solution containing 2mg / mL polyethylene glycol (PEG) and 1mg / mL sodium chloride, and stir at 25,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PTFE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 30°C for 12h to obtain modified polytetrafluoroethylene. According to the contact angle data analysis, the coverage of PEG on the particle surface is 20%.

[0062] Step 2: 50 g of the modified polytetrafluoroethylene particles prepared above were added to 50 mL of deionized water, and stirred at 22,000 rpm in a mechanical stirrer for 3 min to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 69±21 μm.

[0063] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of cyclohexane to prepare a Pickering emulsion with uniform particle size.

[0064] The average particle size of the Pickering emulsion prepared in this embodiment is 65 μm, and the particle size distribution range is 48-90 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0065] Example 7

[0066] Step 1: Add 1g of polyvinylidene fluoride (PVDF) particles to 100mL of an aqueous solution containing 0.1mg / mL polyacrylic acid (PAA) and 0.5mg / mL sodium chloride, and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PVDF particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polyvinylidene fluoride. According to the contact angle data analysis, the coverage of PAA on the particle surface is 10%.

[0067] Step 2: 5 g of the modified polyvinylidene fluoride particles prepared above were added to 50 mL of deionized water, and stirred at 13,000 rpm for 3 min in a mechanical stirrer to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 120±30 μm.

[0068] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of hexane to prepare a Pickering emulsion with uniform particle size.

[0069] The average particle size of the Pickering emulsion prepared in this embodiment is 120 μm, and the particle size distribution range is 90-150 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0070] Example 8

[0071] Step 1: Add 1g of polyvinylidene fluoride (PVDF) particles to 100mL of an aqueous solution containing 2mg / mL polyacrylic acid (PAA) and 1mg / mL sodium chloride, and stir at 25,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PVDF particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 50°C for 8h to obtain modified polyvinylidene fluoride. According to the contact angle data analysis, the coverage of PAA on the particle surface is 20%.

[0072] Step 2: 20 g of the modified polyvinylidene fluoride particles prepared above were added to 50 mL of deionized water, and stirred at 13,000 rpm for 3 min in a mechanical stirrer to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 69±21 μm.

[0073] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of toluene to prepare a Pickering emulsion with uniform particle size.

[0074] The average particle size of the Pickering emulsion prepared in this embodiment is 60 μm, and the particle size distribution range is 48-90 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0075] Example 9

[0076] Step 1: Add 1g of polyvinylidene fluoride (PVDF) particles to 100mL of an aqueous solution containing 0.1mg / mL polyacrylic acid (PAA), and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PVDF particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polyvinylidene fluoride. According to the contact angle data analysis, the coverage of PAA on the particle surface is 5%.

[0077] Step 2: 5 g of the modified polyvinylidene fluoride particles prepared above were added to 50 mL of deionized water, and stirred at 13,000 rpm for 30 seconds in a mechanical stirrer to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 120±30 μm.

[0078] Step 3: Take 1 g of the sieved dry water powder and disperse it in 5 mL of toluene to prepare a Pickering emulsion with uniform particle size.

[0079] The average particle size of the Pickering emulsion prepared in this embodiment is 100 μm, and the particle size distribution range is 90-150 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0080] Example 10

[0081] Step 1: Add 1g of polyvinylidene fluoride (PVDF) particles to 100mL of an aqueous solution containing 1mg / mL polyvinyl alcohol (PVA) and 0.5mg / mL sodium chloride, and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PVDF particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polyvinylidene fluoride. According to the contact angle data analysis, the coverage of PVA on the particle surface is 13%.

[0082] Step 2: 10 g of the modified polyvinylidene fluoride particles prepared above were added to 50 mL of deionized water, and stirred at 13,000 rpm in a mechanical stirrer for 3 min to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 120±30 μm.

[0083] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of petroleum ether to prepare a Pickering emulsion with uniform particle size.

[0084] The average particle size of the Pickering emulsion prepared in this embodiment is 120 μm, and the particle size distribution range is 90-150 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0085] Embodiment 11

[0086] Step 1: Add 1g of polyvinylidene fluoride (PVDF) particles to 100mL of an aqueous solution containing 2mg / mL polyvinyl alcohol (PVA) and 1mg / mL sodium chloride, and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PVDF particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 30°C for 12h to obtain modified polyvinylidene fluoride. According to the contact angle data analysis, the coverage of PVA on the particle surface is 20%.

[0087] Step 2: 50 g of the modified polyvinylidene fluoride particles prepared above were added to 50 mL of deionized water, and stirred at 13,000 rpm for 30 seconds in a mechanical stirrer to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 69±21 μm.

[0088] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of toluene to prepare a Pickering emulsion with uniform particle size.

[0089] The average particle size of the Pickering emulsion prepared in this embodiment is 60 μm, and the particle size distribution range is 48-90 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0090] Example 12

[0091] Step 1: Add 1g of polyvinylidene fluoride (PVDF) particles to 100mL of an aqueous solution containing 2mg / mL polyethylene glycol (PEG) and 0.5mg / mL sodium chloride, and stir at 25,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PVDF particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polyvinylidene fluoride. According to the contact angle data analysis, the coverage of PEG on the particle surface is 20%.

[0092] Step 2: 50 g of the modified polyvinylidene fluoride particles prepared above were added to 50 mL of deionized water, and stirred at 22,000 rpm in a mechanical stirrer for 3 min to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 69±21 μm.

[0093] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of methyl tert-butyl ether to prepare a Pickering emulsion with uniform particle size.

[0094] The average particle size of the Pickering emulsion prepared in this embodiment is 60 μm, and the particle size distribution range is 48-90 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0095] Example 13

[0096] Step 1: Add 1g of polyethylene (PE) particles to 100mL of an aqueous solution containing 0.1mg / mL polyacrylic acid (PAA) and 1mg / mL sodium chloride, and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 50°C for 8h to obtain modified polyethylene. According to the contact angle data analysis, the coverage of PAA on the particle surface is 10%.

[0097] Step 2: 5 g of the modified polyethylene particles prepared above were added to 50 mL of deionized water, and stirred in a mechanical stirrer at 13,000 rpm for 3 min to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 120 ± 30 μm.

[0098] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of toluene to prepare a Pickering emulsion with uniform particle size.

[0099] The average particle size of the Pickering emulsion prepared in this embodiment is 120 μm, and the particle size distribution range is 90-150 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0100] Embodiment 14

[0101] Step 1: Add 1g of polyethylene (PE) particles to 100mL of an aqueous solution containing 2mg / mL polyacrylic acid (PAA) and 0.5mg / mL sodium chloride, and stir at 25,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polyethylene. According to the contact angle data analysis, the coverage of PAA on the particle surface is 20%.

[0102] Step 2: 20 g of the modified polyethylene particles prepared above were added to 50 mL of deionized water, and stirred in a mechanical stirrer at 13,000 rpm for 3 min to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 69±21 μm.

[0103] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of hexane to prepare a Pickering emulsion with uniform particle size.

[0104] The average particle size of the Pickering emulsion prepared in this embodiment is 60 μm, and the particle size distribution range is 48-90 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0105] Embodiment 15

[0106] Step 1: Add 1g of polyethylene (PE) particles to 100mL of an aqueous solution containing 0.1mg / mL polyacrylic acid (PAA), and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polyethylene. According to the contact angle data analysis, the coverage of PAA on the particle surface is 5%.

[0107] Step 2: 5 g of the modified polyethylene particles prepared above were added to 50 mL of deionized water and stirred in a mechanical stirrer at 13,000 rpm for 30 s to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 120 ± 30 μm.

[0108] Step 3: Take 1 g of the sieved dry water powder and disperse it in 5 mL of toluene to prepare a Pickering emulsion with uniform particle size.

[0109] The average particle size of the Pickering emulsion prepared in this embodiment is 100 μm, and the particle size distribution range is 90-150 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0110] Example 16

[0111] Step 1: Add 1g of polyethylene (PE) particles to 100mL of an aqueous solution containing 1mg / mL polyvinyl alcohol (PVA) and 0.5mg / mL sodium chloride, and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polyethylene. According to the contact angle data analysis, the coverage of PVA on the particle surface is 13%.

[0112] Step 2: 10 g of the modified polyethylene particles prepared above were added to 50 mL of deionized water, and stirred in a mechanical stirrer at 13,000 rpm for 3 min to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 120 ± 30 μm.

[0113] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of 2-methyltetrahydrofuran to prepare a Pickering emulsion with uniform particle size.

[0114] The average particle size of the Pickering emulsion prepared in this embodiment is 120 μm, and the particle size distribution range is 90-150 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0115] Embodiment 17

[0116] Step 1: Add 1g of polyethylene (PE) particles to 100mL of an aqueous solution containing 2mg / mL polyvinyl alcohol (PVA) and 1mg / mL sodium chloride, and stir at 15,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 50°C for 8h to obtain modified polyethylene. According to the contact angle data analysis, the coverage of PVA on the particle surface is 20%.

[0117] Step 2: 50 g of the modified polyethylene particles prepared above were added to 50 mL of deionized water and stirred in a mechanical stirrer at 13,000 rpm for 30 seconds to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 69 ± 21 μm.

[0118] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of toluene to prepare a Pickering emulsion with uniform particle size.

[0119] The average particle size of the Pickering emulsion prepared in this embodiment is 60 μm, and the particle size distribution range is 48-90 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0120] Embodiment 18

[0121] Step 1: Add 1g of polyethylene (PE) particles to 100mL of an aqueous solution containing 2mg / mL polyethylene glycol (PEG) and 0.5mg / mL sodium chloride, and stir at 25,000rpm for 30min in a high-speed homogenizer to hydrophilically modify the surface of the PE particles. After stirring, filter the mixture, wash it with deionized water three times, and then dry it at 45°C for 8h to obtain modified polyethylene. According to the contact angle data analysis, the coverage of PEG on the particle surface is 20%.

[0122] Step 2: 50 g of the modified polyethylene particles prepared above were added to 50 mL of deionized water, and stirred in a mechanical stirrer at 22,000 rpm for 3 min to prepare a dry water powder. Subsequently, the dry water powder was sieved through a standard sieve to obtain a dry water powder with a particle size range of 69±21 μm.

[0123] Step 3: Take 1 g of the sieved dry water powder and disperse it in 20 mL of cyclohexane to prepare a Pickering emulsion with uniform particle size.

[0124] The average particle size of the Pickering emulsion prepared in this embodiment is 60 μm, and the particle size distribution range is 48-90 μm. The Pickering emulsion still maintains good stability after being placed at room temperature for 48 hours. The prepared Pickering emulsion with uniform size and stability has strong operability and industrial application prospects, especially in the fields of chemical industry, pharmaceutical industry, food processing, etc., and has important application potential.

[0125] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0126] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A method for preparing a Pickering emulsion of uniform size using dry gouache, characterized in that: The following steps are involved: Step 1, homogenizing and mixing the hydrophobic polymer particles and the hydrophilic polymer solution at a speed of not less than 15,000 rpm for 5 minutes or more, filtering and washing with deionized water after mixing, and then drying at 30-50° C. to obtain modified hydrophobic particles; Step 2, mechanically stirring the modified hydrophobic particles obtained in step 1 with water at a speed of not less than 13,000 rpm for 30 seconds or more to prepare dry water powder, and sieving the obtained dry water powder; Step 3: Disperse the dry water powder obtained after sieving in step 2 into an organic solvent to form a Pickering emulsion.

2. The method according to claim 1, characterized in that The hydrophobic polymer described in step 1 includes at least one of a fluorocarbon polymer, a hydrocarbon polymer, a silicon-containing polymer, a carbonate-containing polymer, an aromatic-containing polymer, a chlorine-containing polymer or a sulfur-containing polymer.

3. The method according to claim 2, characterized in that The carbon-fluorine polymer includes at least one of polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride or ethylene-tetrafluoroethylene copolymer; And / or, the hydrocarbon polymer includes at least one of polystyrene, polypropylene, polyethylene or polymethyl methacrylate; And / or, the silicon-containing polymer includes at least one of polydimethylsiloxane or methyl silicone resin; And / or, the carbonic acid group-containing polymer comprises at least one of polycarbonate or polyether carbonate; and / or, the aromatic polymer comprises at least one of polyethylene terephthalate or polyimide; And / or, the chlorine-containing polymer includes at least one of polyvinyl chloride or chlorinated polyethylene; And / or, the sulfur-containing polymer includes at least one of polyphenylene sulfide or vulcanized rubber.

4. The method according to claim 1, characterized in that: The hydrophilic polymer in step 1 includes at least one of anionic polymer, cationic polymer or nonionic polymer.

5. The method according to claim 4, characterized in that The anionic polymer comprises at least one of polyacrylic acid, sodium polystyrene sulfonate, sodium carboxymethyl cellulose, sodium alginate, sodium polyacrylic acid salt or polyvinyl sulfonate; and / or, the cationic polymer comprises at least one of polydiallyldimethylammonium chloride, polyethyleneimine, chitosan and its derivatives or polydimethyldiallylammonium chloride; and / or, the nonionic polymer comprises at least one of polyvinyl alcohol, polyethylene glycol, polyvinyl pyrrolidone, polyacrylamide, hydroxypropyl methylcellulose or methylcellulose; And / or, the concentration of the hydrophilic polymer solution is 0.1-2 mg / mL.

6. The method according to claim 1, characterized in that The hydrophilic polymer solution in step 1 contains salt.

7. The method according to claim 6, characterized in that The salt includes sodium chloride, and the concentration of the salt is 0-1 mg / mL.

8. The method according to claim 1, characterized in that In step 1, the coverage rate of the hydrophilic polymer on the surface of the hydrophobic polymer particles is 5% to 20%.

9. The method according to claim 1, characterized in that: The size of the screening process in step 2 is 45±15μm, 69±21μm, 90±25μm, 120±30μm, 150±35μm, 190±40μm, 305±75μm or 440±60μm.

10. The method according to claim 1, characterized in that The organic solvent described in step 3 includes at least one of toluene, petroleum ether, methyl tert-butyl ether, n-hexane, cyclohexane, hexadecane, 2-methyltetrahydrofuran, ethyl acetate, benzene, ethanol, acetone or dimethyl sulfoxide.