CN117866229A

CN117866229A - Pickering Janus emulsion and preparation method and application thereof

Info

Publication number: CN117866229A
Application number: CN202311668580.7A
Authority: CN
Inventors: 尚亚卓; 周康夫; 韩旭; 王飞飞; 马骁; 郭振宇
Original assignee: Yunnan Beitani Biotechnology Group Co ltd; Yunnan Yunke Characteristic Plant Extraction Laboratory Co ltd; East China University of Science and Technology
Current assignee: Yunnan Beitani Biotechnology Group Co ltd; Yunnan Yunke Characteristic Plant Extraction Laboratory Co ltd; East China University of Science and Technology
Priority date: 2023-12-06
Filing date: 2023-12-06
Publication date: 2024-04-12

Abstract

The invention belongs to the technical field of emulsion preparation, and particularly relates to Pickering Janus emulsion and a preparation method and application thereof. The Pickering Janus emulsion is prepared from a main emulsifier, a co-emulsifier, a silicone oil component, an oil component, a thickener, a preservative, essence, active functional components and water serving as raw materials; based on 100 percent of the total weight of the raw materials, the main emulsifier accounts for 0.03 to 0.5 percent, the auxiliary emulsifier accounts for 0.1 to 2 percent, the silicone oil component accounts for 3 to 40 percent, the grease component accounts for 3 to 40 percent, the thickener accounts for 0.1 to 0.5 percent, the preservative accounts for 0.1 to 1.0 percent, and the balance is water. The Pickering Janus emulsion prepared by the method has the application advantages of Pickering emulsion and Janus emulsion, and has the advantages of more solubilization selectivity, stronger separation effect, higher stability, better skin permeability, better sensory effect, better rheological property, controllable sustained-release functional ingredient capability and the like.

Description

Pickering Janus emulsion and preparation method and application thereof

Technical Field

The invention belongs to the technical field of emulsion preparation, and particularly relates to Pickering Janus emulsion and a preparation method and application thereof.

Background

When Pickering emulsion (Pickering emulsion) is used for stabilizing an oil-water interface, solid particles are used instead of a surfactant, and the solid particles spontaneously and irreversibly form a compact film layer around a disperse phase, so that the combination of liquid drops is prevented, and the high stability of the emulsion can be maintained. Compared with the stable emulsion of the surfactant, the Pickering emulsion has the advantages of no toxicity, no foam, low environmental pollution, high stability, long-term storage and the like.

Janus emulsions are a special class of emulsions in which the emulsion droplets consist of two hemispheres of an insoluble oil phase component dispersed in a continuous medium. Compared with the common emulsion, the emulsion has more solubilization selectivity and stronger separation effect, and has wide application prospect in the transportation and storage of functional substances. To stabilize Janus emulsions, different surfactants have been explored, such as the nonionic surfactant tween 80 and the amphoteric surfactant phosphatidylcholine. However, the above surfactants are not biodegradable, have no biocompatibility, have adverse effects on the environment, and meanwhile, the prepared Janus emulsion is unstable in thermodynamics and kinetics, so that the Janus emulsion is greatly limited in practical application.

In summary, how to effectively combine Pickering emulsion and Janus emulsion, and further develop a novel Pickering Janus emulsion becomes the problem to be solved at present.

Disclosure of Invention

Based on the technical background, the main purpose of the invention is to provide a Pickering Janus emulsion and a preparation method and application thereof, so as to overcome the defects in the prior art.

In order to achieve the purpose of the invention, the technical scheme adopted by the invention comprises the following steps:

the first aspect of the invention is to provide a Pickering Janus emulsion comprising a main emulsifier, a co-emulsifier, a silicone oil component (O ₁ ) Oil and fat component (O) ₂ ) Raw materials of thickener, preservative and water;

based on 100 percent of the total weight of the raw materials, the main emulsifier accounts for 0.03 to 0.5 percent, the auxiliary emulsifier accounts for 0.1 to 2 percent, the silicone oil component accounts for 3 to 40 percent, the grease component accounts for 3 to 40 percent, the thickener accounts for 0.1 to 0.5 percent, the preservative accounts for 0.1 to 1.0 percent, and the balance is water.

Preferably, the main emulsifier is cellulose nanocrystalline;

the auxiliary emulsifier is selected from emulsifiers with different HLB values, including oil-in-water emulsifier and water-in-oil emulsifier, wherein the oil-in-water emulsifier comprises one or more of lecithin emulsifier, glucoside emulsifier, olive ester emulsifier, phytosterol and higher fatty alcohol emulsifier and polyether emulsifier;

the water-in-oil emulsifier comprises one or more of sesame oil emulsifier, natural olive oil source emulsifier, PEG-10 polydimethylsiloxane emulsifier, sorbitol olive oleate emulsifier and polyglycerol-4 isostearate emulsifier;

the silicone oil component is one or more selected from silicone oil 10 viscosity, silicone oil 50 viscosity, silicone oil 100 viscosity, silicone oil 200 viscosity and silicone oil 350 viscosity;

the oil component is one or more selected from caprylic/capric triglyceride, isooctyl palmitate, saturated isopropyl myristate, shea butter, squalane, fatty alcohol, white mineral oil, shea butter and olive oil;

the thickener is one or more of carbomer thickener, xanthan gum, acrylate and alkyl acrylic acid cross-linked copolymer;

the preservative is one or more of salicylic acid, phenoxyphenol, phenoxyethanol, sodium benzoate, benzyl alcohol, 1, 2-pentanediol, 1, 2-hexanediol and phenoxyethanol-ethylhexyl glycerol (PE 9010).

More preferably, the co-emulsifier is selected from one of lecithin-based emulsifiers, sesame oil emulsifiers, natural olive oil-derived emulsifiers, polyether-based emulsifiers, PEG-10 polydimethylsiloxane emulsifiers and polyglycerol-4 isostearate emulsifiers;

the silicone oil component is selected from one of silicone oil 10 viscosity, silicone oil 50 viscosity, silicone oil 100 viscosity and silicone oil 200 viscosity;

the oil component is one or more selected from caprylic/capric triglyceride, isooctyl palmitate, keratin shark and olive oil;

the thickener is carbomer thickener.

Preferably, the raw materials further comprise essence and active functional ingredients.

Based on the total weight of the raw materials as 100%, the essence accounts for 0.01% -0.3%, and the active functional components account for 0.01% -10.0%;

the active functional component is selected from one or more of vitamin E, astaxanthin, retinol palmitate, ascorbyl tetraisopalmitate (VCIP), hydroxy Pinacolin Retinoate (HPR) and bakuchiol.

In a second aspect, the present invention provides a method for preparing the Pickering Janus emulsion according to the first aspect, which is characterized in that the method comprises the following steps:

step 1, mixing a co-emulsifier, a silicone oil component and an oil component to obtain an oil phase;

step 2, homogenizing the main emulsifying agent, the thickening agent and water to obtain a water phase;

and step 3, adding the oil phase into the water phase for homogenizing treatment, and then adding the preservative for continuing homogenizing treatment to obtain the Pickering Janus emulsion.

Preferably, in the step 1, if the auxiliary emulsifier is solid, the auxiliary emulsifier is heated to 70-80 ℃ to be preheated until the solid is completely dissolved;

active functional components can also be added in the oil phase mixing process.

Preferably, in step 2, homogenization is performed at a homogenization speed of 7000 to 8500rpm at room temperature;

if the thickener is carbomer thickener, sodium hydroxide solution is added to adjust the system acid-base, wherein the mass ratio of carbomer to 10% sodium hydroxide solution is 1:2.

preferably, in step 3, the oil phase is added into the water phase and homogenized for 5-10 min at a homogenization speed of 7500-8000 rpm, and then the alkali solution and the preservative are added and homogenized for 2-5 min at a homogenization speed of 7500-8000 rpm.

The third aspect of the invention is to provide an application of the Pickering Janus emulsion in the field of daily cosmetics.

The invention has the beneficial effects that:

(1) The Pickering Janus emulsion disclosed by the invention takes the cellulose nano-crystal as the main emulsifier, has excellent slow-release characteristics, can realize the regulation and control of the slow-release behavior of the functional substances by adjusting the content of the auxiliary emulsifier and the volume ratio of the oil, does not contain any surfactant with toxic or side effects, is high in safety, is more friendly to human bodies and the environment, and is suitable for the field of daily cosmetics.

(2) The Pickering Janus emulsion provided by the invention has better skin permeability, better sensory effect and better rheological property. The emulsion provides a new design idea for the development of novel emulsified products.

(3) Based on the existing vibration mixing method, microfluidic technology and solvent evaporation method, the preparation method provided by the invention adopts a one-step homogenization method, and is simple and feasible.

(4) The Pickering Janus emulsion prepared by the invention can be used for preparing emulsion with excellent stability, has no layering phenomenon when being placed for half a year at normal temperature, is stable when being circulated at high and low temperatures, and can meet the requirement of long shelf life of cosmetics.

(5) The Pickering Janus emulsion prepared by the invention has more solubilization selectivity and stronger separation effect, and has wide application prospect in the transportation and storage of functional substances.

Drawings

FIG. 1 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 1;

FIG. 2 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 2;

FIG. 3 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 3;

FIG. 4 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 4;

FIG. 5 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 6;

FIG. 6 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 7;

FIG. 7 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 8;

FIG. 8 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 9;

FIG. 9 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 10;

FIG. 10 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 11;

FIG. 11 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 12;

FIG. 12 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 13;

FIG. 13 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 14;

FIG. 14 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 15;

FIG. 15 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 16;

FIG. 16 shows a polarized photomicrograph of the Pickering Janus emulsion prepared in example 17;

fig. 17 shows the slow release profile of vitamin E in the Pickering Janus emulsions prepared in example 1, example 2, example 3;

fig. 18 shows the slow release profile of vitamin E in the Pickering Janus emulsions prepared in example 4, example 5, example 6;

FIG. 19 shows the viscosity as a function of shear rate for Pickering Janus emulsions prepared in example 1.

Detailed Description

The features and advantages of the present invention will become more apparent and evident from the following detailed description of the invention.

The first aspect of the invention is to provide a Pickering Janus emulsion which is prepared from raw materials comprising a main emulsifier, a co-emulsifier, a silicone oil component, a grease component, a thickener, a preservative and water.

Based on the total weight of the raw materials as 100%, the main emulsifier accounts for 0.03% -0.5%, the auxiliary emulsifier accounts for 0.1% -2%, and the silicone oil component (O) ₁ ) 3% -40%, and oil component (O) ₂ ) 3 to 40 percent of thickener, 0.1 to 0.5 percent of preservative, 0.1 to 1.0 percent of preservative and the balance of water.

Preferably, the total weight of the raw materials is 100%, the main emulsifier accounts for 0.05-0.2%, the auxiliary emulsifier accounts for 0.2-1.5%, the silicone oil component accounts for 3-40%, the grease component accounts for 3-40%, the thickener accounts for 0.18%, the preservative accounts for 0.6%, and the balance is water.

The primary emulsifier is preferably cellulose nanocrystals. The cellulose nanocrystalline is one of the most promising green materials at present, and the special rod-shaped structure is very suitable for preparing Pickering emulsion, and has the characteristics of renewable cellulose, degradability and biocompatibility. Studies have shown that rod-shaped solid particles are more stable than emulsions formed from spherical solid particles, because they crosslink more readily at the surface of the droplets to form a network. The solid emulsifier particles are low in price, small in addition amount and low in cost, meanwhile, the oil-in-oil quantity of the emulsified product is high, the loading capacity of functional components can be improved, the slow-release functional components can be effectively embedded, and the emulsion has excellent skin feel.

The raw materials also comprise essence and active functional components, wherein the total weight of the raw materials is 100 percent, the essence accounts for 0.01 to 0.3 percent, the active functional components account for 0.01 to 10.0 percent, the essence accounts for 0.05 to 0.2 percent preferably, and the active functional components account for 0.05 to 4 percent.

The auxiliary emulsifier is selected from one or more of emulsifiers with different HLB values, wherein the oil-in-water emulsifier comprises lecithin emulsifier, glucoside emulsifier, olive ester emulsifier, phytosterol, higher fatty alcohol emulsifier and polyether emulsifier; the water-in-oil emulsifier comprises one or more of sesame oil emulsifier, natural olive oil source emulsifier, PEG-10 polydimethylsiloxane emulsifier, sorbitol olive oleate emulsifier and polyglycerol-4 isostearate emulsifier.

Preferably, the coemulsifier is selected from one of lecithin-based emulsifiers (nikk mulese LC (NIKKOL corporation, japan), prolipid (ISP corporation, usa) or EM-001 (shanghai plant biotechnology limited)), sesame oil emulsifier, natural olive oil-derived emulsifier, PPG-13-decyl tetradecanoyl polyether-24 emulsifier, PEG-10 polydimethylsiloxane emulsifier and polyglycerol-4 isostearate emulsifier.

Lecithin is used as a main component of a cell membrane, has a special self-assembled amphiphilic structure, so that the lecithin emulsifier has excellent characteristics of self-assembly, emulsification, wetting and the like, and has excellent biocompatibility.

The silicone oil component is selected from one or more of silicone oil 10 viscosity, silicone oil 50 viscosity, silicone oil 100 viscosity, silicone oil 200 viscosity and silicone oil 350 viscosity, preferably one of silicone oil 10 viscosity, silicone oil 50 viscosity and silicone oil 100 viscosity and silicone oil 200 viscosity.

The oil component is one or more selected from caprylic/capric triglyceride, isooctyl palmitate, saturated isopropyl myristate, shea butter, squalane, fatty alcohol, white mineral oil, shea butter and olive oil.

Preferably, the oil component is selected from one or more of Caprylic/capric triglyceride (capric/capric triglyceride, GTCC), isooctyl palmitate (2-Ethylhexyl palmitate,2 EHP), saturated isopropyl myristate (Isopropyl myristate, IPM), shea butter, squalane, and olive oil. More preferably one or more selected from GTCC, 2EHP, keratin shark and olive oil.

The oil components have the following functions:

the caprylic/capric triglyceride (GTCC) is a kind of high-refreshing odorless grease, has good compatibility with human skin, can achieve the effects of lubricating and promoting skin to be soft, and has the function of filtering ultraviolet light to a certain extent.

Isooctyl palmitate (2 EHP) is a skin softener, has strong skin permeability, strong antiperspirant efficacy and skin affinity, and stable performance.

Saturated isopropyl myristate (IPM) is a skin penetration enhancer widely used in cosmetics and has effects of moisturizing and nourishing skin, and it can penetrate deep into skin and bring active ingredients in the preparation into the skin.

The shea butter has anti-inflammatory effect on skin, can prevent erythema and erythema caused by ultraviolet irradiation, and can be used for repairing after sunburn even if skin is sunburned. The antioxidant and vitamins contained in the skin care cream can prevent aging, remove wrinkles after long-term use, provide nutrition for skin and enable the skin to be glossy and elastic.

Squalane is an animal fat with high chemical stability and better skin affinity, is used as a lipid closest to human sebum, has high moistening and moisturizing properties, can inhibit peroxidation of skin lipid, promote metabolism of cells, and help repair damaged cells.

The olive oil is rich in squalene with excellent affinity to skin and fatty acid necessary for human body, can be absorbed rapidly, can effectively keep skin elasticity and luster, contains abundant unsaturated fatty acid, vitamin K, vitamin E, vitamin A, vitamin D and the like, and phenolic antioxidant substances, can eliminate facial wrinkles, prevent skin aging, and has the effects of protecting skin, hair and preventing rhagadia manus et pedis.

The thickener is one or more of carbomer thickener, xanthan gum, acrylate and alkyl acrylic acid cross-linked copolymer; the thickener is preferably a carbomer thickener, more preferably a U21 thickener.

The preservative is one or more of salicylic acid, phenoxyphenol, phenoxyethanol, sodium benzoate, benzyl alcohol, 1, 2-pentanediol, 1, 2-hexanediol and phenoxyethanol-ethylhexyl glycerol (PE 9010); PE9010 is preferred.

The alkali solution is preferably an aqueous sodium hydroxide solution, more preferably an aqueous sodium hydroxide solution having a mass fraction of 10%.

In a second aspect, the present invention provides a method for preparing the Pickering Janus emulsion according to the first aspect of the present invention, the method comprising the steps of:

step 1, mixing a co-emulsifier, a silicone oil component and an oil component, and then heating and preheating until the solid is completely dissolved to obtain an oil phase;

step 2, adding a main emulsifier, a thickener and an alkali solution into water for homogenization treatment to obtain a water phase;

and step 3, adding the oil phase into the water phase for homogenizing treatment, and then adding an alkali solution and a preservative for continuing homogenizing treatment to obtain the Pickering Janus emulsion.

The above steps are specifically described below.

In the step 1, if the auxiliary emulsifier is solid, the temperature is raised to 70-80 ℃ to preheat the auxiliary emulsifier until the solid is completely dissolved, and the temperature is raised to 75 ℃ to preheat the auxiliary emulsifier.

In step 2, the homogenization is performed at a homogenization speed of 7000 to 8500rpm at room temperature, preferably at a homogenization speed of 7800rpm at room temperature.

In the step 3, the oil phase is added into the water phase and homogenized for 5 to 10min at a homogenizing speed of 7500 to 8000rpm, and then the alkali solution and the preservative are added and homogenized for 2 to 5min at a homogenizing speed of 7500 to 8000 rpm.

Preferably, the oil phase is added to the aqueous phase and homogenized for 7min at a homogenization speed of 7800rpm, and then the addition of the alkaline solution and preservative is continued for 3min at a homogenization speed of 7800 rpm.

Compared with the traditional Janus emulsion, the Pickering Janus emulsion prepared by the invention has obvious improvement on the aspects of skin safety and stability, and is mainly due to the fact that the cellulose nanocrystalline serving as a main emulsifier used by the system is green and pollution-free, and the rod-shaped structure of the cellulose nanocrystalline is easier to crosslink on the surface of liquid drops to form a network structure.

In a third aspect, the invention provides an application of the Pickering Janus emulsion in the cosmetic field. Active ingredients including, but not limited to, vitamin E are preferably added to the Pickering Janus emulsion for use in the field of cosmetics for daily use.

Examples

The invention is further illustrated by the following specific examples, which are intended to be illustrative of the invention and are not intended to limit the scope of the invention.

Example 1

Weighing the raw materials by weight percentage, wherein the sum of the weight of the raw materials is 100%, the weight percentage of the raw materials is 0.1% of cellulose nanocrystalline, 0.2% of lecithin emulsifier and 100% of silicone oil viscosity (O) ₁ )10％，GTCC(O ₂ ) 7% of vitamin E3%, 0.18% of U21 (carbomer thickener), 0.6% of PE9010, 0.36% of 10wt% of NaOH aqueous solution and the balance of purified water.

The lecithin emulsifier and silicone oil 100 (O ₁ )、GTCC(O ₂ ) Mixing with vitamin E, and preheating in a constant temperature water bath at 75deg.C until the solid is completely dissolved to obtain oil phase.

The cellulose nanocrystals, U21 and 10wt% aqueous NaOH solution were weighed and added to purified water as aqueous phase, the addition amount of the aqueous NaOH solution was 1/3 of the total mass of the weighed aqueous NaOH solution, and the aqueous phase was homogenized at room temperature at a homogenization speed of 7800rpm to dissolve and disperse uniformly.

Slowly adding the completely dissolved oil phase into the water phase, homogenizing for 7min at a homogenizing speed of 7800rpm, adding the rest 10wt% of NaOH aqueous solution (2/3 of the total mass of the weighed NaOH aqueous solution) and PE9010, continuously homogenizing for 3min at a homogenizing speed of 7800rpm to obtain Pickering Janus emulsion, cooling to room temperature, and packaging.

Example 2

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 1, except that: the addition amount of lecithin emulsifier was 0.35%.

Example 3

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 1, except that: the addition amount of lecithin emulsifier was 0.5%.

The Pickering Janus emulsions prepared in examples 1 to 3 were observed by using a Nikon polarizing microscope, and the photographs thereof were shown in FIGS. 1,2 and 3, respectively. From fig. 1 to fig. 3, it is clear that the emulsion droplet sizes of the Pickering Janus emulsions prepared in examples 1 to 3 are uniform, which indicates that the Pickering Janus emulsions with uniform emulsion droplet sizes can be formed when the addition amount of the emulsifier is 0.2 to 0.5%.

Example 4

Weighing the raw materials by weight percentage, wherein the sum of the weight percentages of the raw materials is 100%, the cellulose nanocrystalline is 0.1%, the lecithin emulsifier is 0.35%, and the silicone oil is 100 viscosity (O) ₁ )5％，GTCC(O ₂ ) 15%, vitamin E3%, U21.18%, PE 9010.6%, 10% NaOH aqueous solution 0.36% by weight, and the balance being purified water.

Example 5

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 4, except that: silicone oil 100 was adhered (O ₁ )5％、GTCC(O ₂ ) 15% replacement with silicone oil 100 viscosity (O ₁ )10％、GTCC(O ₂ )10％。

Example 6

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 4, except that: silicone oil 100 was adhered (O ₁ )5％、GTCC(O ₂ ) 15% replacement with silicone oil 100 viscosity (O ₁ )15％、GTCC(O ₂ )10％。

The Pickering Janus emulsions prepared in example 4 and example 6 were observed with a Nikon polarizing microscope, the photographs of which are shown in FIG. 4 and FIG. 5, respectively, and as can be seen from FIGS. 4 and 5, O ₁ And O ₂ The emulsion drops of Pickering Janus emulsion prepared by adopting different proportions are uniform in size.

Example 7

Weighing the raw materials according to the weight percentage by taking the sum of the weight of the raw materials as 100 percent, wherein the weight percentage of the raw materials is 0.1 percent, the weight percentage of the cellulose nanocrystalline is 1 percent, the weight percentage of the lecithin emulsifier is 1 percent, the weight percentage of the silicone oil is 10 percent, and the mass ratio of the mixed grease (GTCC, 2EHP and olive oil is 5:2:3) (O ₂ ) 10%, U210.18%, PE 9010.6%, 10% by weight of aqueous NaOH 0.36% and the balance of purified water.

The lecithin emulsifier and silicone oil 10 (O) ₁ ) And mixed oils (GTCC, 2EHP and olive oil quality)The weight ratio is 5:2: 3) (O) ₂ ) Mixing, and preheating in a constant-temperature water bath at 75 ℃ until the solid is completely dissolved to obtain an oil phase.

Example 8

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 7, except that: silicone oil 10 viscosity was replaced with silicone oil 200 viscosity.

The Pickering Janus emulsions prepared in example 7 and example 8 were observed by using a Nikon polarizing microscope, and the observation photographs thereof are shown in FIG. 6 and FIG. 7, respectively, and it can be seen from FIG. 6 and FIG. 7 that Pickering Janus emulsions with uniform emulsion droplet size can be prepared when the silicone oil viscosity is 10-200.

Example 9

Weighing the raw materials according to the weight percentage by taking the sum of the weight of the raw materials as 100%, wherein the weight percentage of the raw materials is 0.1% of cellulose nanocrystalline, 1% of lecithin emulsifier, 10% of silicone oil 100 viscosity and grease (keratan shark) (O) ₂ ) 10%, U21.18%, PE 9010.6%, 10% by weight of NaOH aqueous solution 0.36% and the balance of purified water.

The lecithin emulsifier and silicone oil 100 (O ₁ ) And fat (shark) (O) ₂ ) Mixing, and preheating in a constant-temperature water bath at 75 ℃ until the solid is completely dissolved to obtain an oil phase.

Example 10

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 9, except that: the canthaxanthin shark was replaced with 2EHP.

The Pickering Janus emulsions prepared in example 9 and example 10 were observed by using a Nikon polarizing microscope, and the observation photographs thereof are shown in FIG. 8 and FIG. 9, respectively, and it can be seen from FIG. 8 and FIG. 9 that Pickering Janus emulsions with uniform emulsion droplet size can be prepared when the oil and fat is 2EHP or squalane.

Example 11

The weight percentage of the raw materials is calculated by taking the sum of the weight percentages of the raw materials as 100%, the raw materials are weighed according to the weight percentages, the cellulose nanocrystalline is 0.1%, the PEG-10 polydimethylsiloxane is 1%, the silicone oil is 100-10%, the mass ratio of the mixed grease (GTCC, 2EHP and olive oil is 5:2:3) (O ₂ ) 10% of the mixture, 0.18% of U21, 0.6% of PE9010, 0.36% of 10% by weight of NaOH aqueous solution and the balance of purified water are mixed.

The obtained PEG-10 polydimethylsiloxane and silicone oil were 100-bonded (O ₁ ) And mixed grease (GTCC, 2EHP and olive oil mass ratio of 5:2: 3) (O) ₂ ) Mixing, and preheating in a constant-temperature water bath at 75 ℃ until the solid is completely dissolved to obtain an oil phase.

The cellulose nanocrystalline, U21 and 10wt% NaOH aqueous solution are added into purified water to be used as water phase, the addition amount of the NaOH aqueous solution is 1/3 of the total mass of the weighed NaOH aqueous solution, and the water phase is homogenized at room temperature to be dissolved and dispersed uniformly.

Example 12

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 11, except that: the PEG-10 polydimethylsiloxane emulsifier was replaced with PPG-13-decyl tetradecyl polyether-24 emulsifier.

Example 13

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 11, except that: the PEG-10 polydimethylsiloxane emulsifier was replaced with a polyglycerol-4 isostearate emulsifier.

Example 14

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 11, except that: 1% of PEG-10 polydimethylsiloxane emulsifier was replaced with 1.5% of sesame oil emulsifier.

Example 15

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 11, except that: 1% of the PEG-10 polydimethylsiloxane emulsifier was replaced with 1.5% of the natural olive oil source emulsifier.

The Pickering Janus emulsions prepared in examples 11 to 15 were observed by using a Nikon polarizing microscope, and the observation photographs thereof are shown in FIG. 10, FIG. 11, FIG. 12, FIG. 13 and FIG. 14, respectively, and it is apparent from the figures that Pickering Janus emulsions were prepared by using the above-mentioned emulsifiers and the emulsifier contents, and the emulsion droplets in the emulsions were uniform in size.

Example 16

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 4, except that: weighing the raw materials by weight percentage, wherein the sum of the weight of the raw materials is 100%, the weight percentage of the raw materials is 0.2% of cellulose nanocrystalline, 0.1% of lecithin emulsifier and 100% of silicone oil viscosity (O) ₁ )3％，GTCC(O ₂ )20％、2EHP(O ₂ ) 8% olive oil (O) ₂ )12％、U21(Carbomer thickener) 0.18%, PE 9010.6%, 10wt% NaOH aqueous solution 0.36%, the remainder being purified water.

Example 17

The preparation of the Pickering Janus emulsion was carried out in a similar manner to example 4, except that: weighing the raw materials by weight percentage, wherein the sum of the weight of the raw materials is 100%, the weight percentage of the raw materials is 0.2% of cellulose nanocrystalline, 0.1% of lecithin emulsifier and 100% of silicone oil viscosity (O) ₁ )30％，GTCC(O ₂ ) 3%, U21 (carbomer thickener) 0.18%, PE 9010.6%, 10% NaOH aqueous solution 0.36% by weight, and the balance purified water.

The Pickering Janus emulsions prepared in example 16 and example 17 were observed by using a Nikon polarizing microscope, and the observation photographs thereof are shown in FIG. 15 and FIG. 16, respectively, and it is apparent from the figures that Pickering Janus emulsions can be prepared by using the silicone oil component and the oil component, and the emulsion droplets in the emulsions are uniform in size.

Experimental example

Experimental example 1 in vitro sustained Release Performance test

The sustained release properties of Pickering Janus emulsions prepared in examples 1-6 were tested separately in an in vitro dialysis experiment using vitamin E as the detection component. The Pickering Janus emulsions prepared in examples 1-6 were each subjected to the following procedure: absolute ethyl alcohol is selected as a slow release environment of vitamin E drugs. To a dialysis bag having a molecular weight cut-off of 3500Da, 1.0g of vitamin E-entrapped emulsion was added, and the dialysis bag was then placed in a beaker containing 100mL of dialysate. The beaker was sealed and subjected to constant temperature shaking at 37℃at 100 r/min. In the test process, 5mL of vitamin E dialysate is taken out at regular intervals according to preset time intervals, and the same volume of dialysate is replenished in a beaker. The ultraviolet absorption value of the extracted solution was measured at 284.5nm wavelength using an ultraviolet spectrophotometer (UV-2450, shimadzu, japan), and the corresponding release amount was calculated according to the ultraviolet regression equation of vitamin E. The results of the slow release performance test of examples 1 to 3 are shown in FIG. 17, and the results of the slow release performance test of examples 4 to 6 are shown in FIG. 18.

As can be seen from fig. 17: the release rate of vitamin E in the Pickering Janus emulsions prepared in examples 1-3 was relatively slow, and the slow release effect was also different depending on the lecithin emulsifier content. By changing the content of the auxiliary emulsifier (lecithin emulsifier) to influence the interfacial tension, the obvious difference of the interfacial tension between the oil components at the water interface in the emulsion leads to the formation of completely engulfed emulsion droplets, and the similar interfacial tension is responsible for forming dumbbell-shaped droplets, so that the control of the topology structure of the droplets in the emulsion is realized. At a lecithin emulsifier content of 0.35%, the release rate of vitamin E was lower than that of 0.2% and 0.5% because the silicone oil component in the Pickering Janus emulsion droplets had a larger area of inhibition against the release of the functional ingredient at a lecithin emulsifier content of 0.35%.

As can be seen from fig. 18: the release rate of vitamin E in Pickering Janus emulsions prepared in examples 3-4 was relatively slow, and the slow release effect was also different depending on the oil content. The control of the liquid drop topological structure in the emulsion is realized by changing the different content proportion of the grease. It can be seen from the figure that the larger the silicone oil phase content ratio, the slower the slow release result. This is because the silicone oil component has a larger area of obstruction to the release of the functional ingredient.

Experimental example 2 rheological Property test

For cosmetic emulsions, the skin feel of the product is very important. The skin feel of the product is closely related to the viscosity and thixotropic property of the cosmetic, so the skin feel experience can be reflected by the rheological property of the emulsion. Rheological properties of the Pickering Janus emulsion prepared in example 1 were tested, and FIG. 19 is a plot of viscosity versus shear rate for the Pickering Janus emulsion prepared in example 1.

As can be seen from fig. 19: pickering Janus emulsions are typically shear-thinning non-Newtonian fluids in which the viscosity of the emulsion decreases as the shear rate increases. When the sample is not acted by shearing force in the storage process, the viscosity of the multiple emulsion is higher, and the storage stability is good; when the sample is subjected to friction shearing in the smearing process, the viscosity of multiple emulsions is reduced, and the emulsion has good spreadability on the surface of skin and shows good skin feel.

The invention has been described in detail in connection with the specific embodiments and exemplary examples thereof, but such description is not to be construed as limiting the invention. It will be understood by those skilled in the art that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its embodiments without departing from the spirit and scope of the present invention, and these fall within the scope of the present invention. The scope of the invention is defined by the appended claims.

Claims

1. The Pickering Janus emulsion is characterized by being prepared from raw materials comprising a main emulsifier, a co-emulsifier, a silicone oil component, an oil component, a thickener, a preservative and water;

2. The Pickering Janus emulsion according to claim 1, wherein,

the main emulsifier is cellulose nanocrystalline;

the auxiliary emulsifier is selected from emulsifiers with different HLB values, including oil-in-water emulsifier and water-in-oil emulsifier, wherein the oil-in-water emulsifier comprises one or more of lecithin emulsifier, glucoside emulsifier, olive ester emulsifier, phytosterol, higher aliphatic alcohol and polyether emulsifier;

the water-in-oil emulsifier comprises one or more of sesame oil emulsifier, natural olive oil source emulsifier, PEG-10 polydimethylsiloxane, sorbitol olive oleate and polyglycerol-4 isostearate;

the preservative is one or more of salicylic acid, phenoxyphenol, phenoxyethanol, sodium benzoate, benzyl alcohol, 1, 2-pentanediol, 1, 2-hexanediol and phenoxyethanol-ethylhexyl glycerol.

3. The Pickering Janus emulsion according to claim 2, wherein,

the auxiliary emulsifier is selected from one of lecithin emulsifier, sesame oil emulsifier, natural olive oil source emulsifier, alcohol polyether emulsifier, PEG-10 polydimethylsiloxane emulsifier and polyglycerol-4 isostearate emulsifier;

the thickener is carbomer thickener.

4. The Pickering Janus emulsion of claim 1, wherein the raw materials further comprise a perfume and an active efficacy ingredient;

the active functional component is one or more selected from vitamin E, astaxanthin, retinol palmitate, ascorbyl tetraisopalmitate, hydroxy pinacolone retinoate and bakuchiol.

5. A method for preparing a Pickering Janus emulsion according to any one of claims 1 to 4, characterized in that it comprises the following steps:

step 1, mixing an auxiliary emulsifier, a silicone oil component and an oil component to obtain an oil phase;

step 2, adding the main emulsifying agent and the thickening agent into water for homogenizing treatment to obtain a water phase;

and step 3, adding the oil phase into the water phase for homogenization treatment, and then adding a preservative for continuous homogenization treatment to obtain the Pickering Janus emulsion.

6. The method according to claim 5, wherein, in step 1,

if the auxiliary emulsifier is solid, the temperature is raised to 70-80 ℃ to preheat the auxiliary emulsifier until the solid is completely dissolved;

active functional components can also be added in the oil phase mixing process.

7. The method according to claim 5, wherein, in step 2,

homogenizing at room temperature at a homogenizing speed of 7000-8500 rpm;

8. the method according to claim 5, wherein, in step 3,

adding the oil phase into the water phase, homogenizing for 5-10 min at a homogenizing speed of 7500-8000 rpm, then adding the alkali solution and the preservative, and continuing homogenizing for 2-5 min at a homogenizing speed of 7500-8000 rpm.

9. Use of a Pickering Janus emulsion according to any one of claims 1 to 4 in the field of cosmetics for daily use.