Self-antibacterial high-stability zinc stearate emulsion and preparation method thereof

Abstract

The invention relates to the technical field of zinc stearate, and particularly discloses a self-antibacterial high-stability zinc stearate emulsion and a preparation method thereof.The self-antibacterial high-stability zinc stearate emulsion is prepared from 100 parts of deionized water, 10-50 parts of zinc stearate, 0.1-2 parts of an emulsifier A, 0.1-2 parts of an emulsifier B, 0.1-1 part of a stabilizer A, 0.1-1 part of a stabilizer B and 10-50 parts of a co-emulsifier. The invention also discloses a preparation method of the zinc stearate emulsion, which comprises the following steps: heating or melting the co-emulsifier, and adding the emulsifier A, the emulsifier B and the zinc stearate under a stirring condition to completely dissolve the zinc stearate to obtain an oil phase; deionized water is added into the oil phase, the system gradually generates phase reversal, the system is converted into oil-in-water from water-in-oil, and the viscosity of the system is rapidly reduced; then adding the stabilizer A and the stabilizer B to obtain the self-antibacterial high-stability zinc stearate emulsion which is small in particle size, low in viscosity, free of layering, free of preservatives, short in production process and low in production cost.

Description

Technical Field

[0001] This invention relates to the field of zinc stearate technology, specifically to a self-antibacterial, highly stable zinc stearate emulsion and its preparation method. Background Technology

[0002] Zinc stearate emulsion has excellent lubrication and isolation properties and is widely used in the rubber, plastics, coatings, adhesives, cosmetics and paper industries. Zinc stearate is a low surface energy substance with a low critical surface tension. Emulsifiers do not easily adsorb on the surface of zinc stearate and require strong mechanical force to barely wet it. The emulsification effect is poor and unstable, and the emulsion is prone to separation.

[0003] For example, Chinese patent number 202110333189.6 mentions a highly stable calcium stearate emulsion and its preparation method, comprising stearic acid, emulsifier, surfactant, anti-flocculator, defoamer, electrolyte, stabilizer, calcium hydroxide, and deionized water; this invention also discloses a method for preparing a highly stable calcium stearate emulsion. The advantage of this invention is that, after optimization of the raw material composition ratio, it provides a water-soluble calcium stearate emulsion with high solid content, low viscosity, and high stability, achieving a solid content of 50%, small particle size (0.1–0.5 μm), and a viscosity of 400–450 poise.

[0004] Currently, zinc stearate emulsions are mainly prepared through direct emulsification and primary saponification. Direct emulsification involves pre-dispersing water, zinc stearate, dispersants, wetting agents, and emulsifiers under stirring conditions, followed by ultrasonication, grinding, and filtration to obtain an aqueous zinc stearate emulsion. However, this process has the following disadvantages: ① The preparation process is complex, lengthy, and costly; ② High emulsifier usage makes the emulsion susceptible to bacterial corrosion and demulsification, generally requiring the addition of environmentally unfriendly preservatives; ③ Poor emulsion stability, prone to stratification, sedimentation, and Austronesian ripening (small droplets have a higher chemical potential than large droplets, and the chemical potential tends to decrease naturally; small droplets gradually coalesce into larger droplets to lower the chemical potential; this phenomenon is called Austronesian ripening).

[0005] The primary saponification method involves reacting zinc oxide, stearic acid, emulsifiers, catalysts, and other additives at high temperature and with a certain stirring intensity to produce zinc stearate. A secondary reaction is then achieved through grinding and refining to obtain the final product. This process has the following disadvantages: ① It involves complex production processes, high reaction temperatures, long reaction times, and high production costs; ② A large amount of unreacted zinc oxide and stearic acid remain in the emulsion, resulting in an impure system that affects downstream manufacturers' use. Based on these drawbacks, we propose a self-antibacterial, highly stable zinc stearate emulsion and its preparation method. Summary of the Invention

[0006] The purpose of this invention is to provide a self-antibacterial, highly stable zinc stearate emulsion to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A self-antibacterial, highly stable zinc stearate emulsion comprises the following components: deionized water: 100 parts, zinc stearate: 10-50 parts, emulsifier A: 0.1-2 parts, emulsifier B: 0.1-2 parts, stabilizer A: 0.1-1 part, stabilizer B: 0.1-1 part, and co-emulsifier: 10-50 parts.

[0009] Preferably, the co-emulsifier is composed of at least one or more of the following substances that can dissolve zinc stearate: turpentine, stearic acid, octadecanol, lauric acid, lauryl alcohol, benzene, toluene, methanol, ethanol, propanol, butanol, ethylene glycol, glycerin, etc.

[0010] Preferably, emulsifier A is a nonionic surfactant, emulsifier B is an anionic surfactant, and emulsifier A and emulsifier B are compounded in a ratio of 9:1 to 5:5 to form a composite emulsifier.

[0011] The advantage of adopting the above technical solution is that it can reduce the surface tension of the emulsion system and improve the stability of the emulsion.

[0012] Preferably, the emulsifier A is selected from one or more combinations of polyoxyethylene sorbitol monolaurate, polyoxyethylene sorbitol monostearate, polyoxyethylene sorbitol monooleate, tetraethylene glycol monostearate, polyethylene glycol monostearate, fatty alcohol polyoxyethylene ether, sorbitol monolaurate, sorbitol monostearate, and sorbitol monooleate; and the emulsifier B is selected from one or more combinations of sodium stearate, potassium stearate, sodium laurate, sodium oleate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, sodium dinaphthalene disulfonate, sodium dibutylnaphthalene sulfonate, and sodium dodecyl sulfate.

[0013] Preferably, stabilizer A is an organic stabilizer and stabilizer B is an inorganic stabilizer, and the two are compounded in a ratio of 9:1 to 5:5 to form a composite stabilizer.

[0014] The advantage of adopting the above technical solution is that it can have a synergistic stabilizing effect and improve the stability of the emulsion.

[0015] Preferably, stabilizer A is selected from one or more of starch, hydroxymethyl cellulose, gelatin, xanthan gum, gum arabic, polyvinyl alcohol, and polyacrylic acid resin, and stabilizer B is selected from one or more of sodium metasilicate, calcium carbonate, bentonite, and silicon dioxide.

[0016] A method for preparing a self-antibacterial, highly stable zinc stearate emulsion includes the following steps:

[0017] S1: Heat or melt the co-emulsifier, and add emulsifier A, emulsifier B, and zinc stearate under stirring conditions of 100-200 r / min to completely dissolve the zinc stearate and emulsifier, thus obtaining the oil phase;

[0018] S2: Under stirring conditions of 200-2000 r / min, deionized water is added to the oil phase. The system gradually reverses phase, and the system changes from water in oil to oil in water. The viscosity of the system decreases rapidly, and pre-dispersed emulsion A is obtained.

[0019] S3: Under stirring conditions of 200-1000 r / min, stabilizer A and stabilizer B are added to the pre-dispersed emulsion A to obtain a self-antibacterial, highly stable zinc stearate emulsion.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] (1) The present invention prepares zinc stearate emulsion and introduces an emulsifying system with antibacterial function to achieve multiple effects such as antibacterial, particle size reduction and emulsion stability improvement, thereby improving emulsion stability while avoiding the use of preservatives.

[0022] (2) The zinc stearate emulsion prepared by the present invention has small particle size, low viscosity and fine texture. It does not separate into layers after centrifugation for 2 hours under high speed centrifugation at 4000 r / min, and the emulsion has high stability.

[0023] (3) The zinc stearate emulsion and its preparation method of the present invention only require one emulsifier to complete the entire emulsification process, without the need for a high-energy-consuming mixing process. The manufacturing process is simple, the process is short, the energy consumption is low, and the production cost is low. Attached Figure Description

[0024] Figure 1 The figure shows the performance test results of the self-antibacterial and highly stable zinc stearate emulsion in the embodiments of the present invention. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1:

[0027] In this example, the zinc stearate emulsion is composed of the following components: 100 parts deionized water, 10 parts zinc stearate, 0.1 parts polyoxyethylene sorbitan monolaurate (Tween-20), 0.1 parts sodium stearate, 0.1 parts starch, 0.1 parts sodium metasilicate, 5 parts turpentine oil, and 5 parts methanol.

[0028] The preparation method is as follows:

[0029] (1) Mix turpentine oil and methanol, heat to 30°C, keep warm for 5 min, and add polyoxyethylene sorbitol monolaurate (Tween-20), sodium stearate and zinc stearate under stirring at 100 r / min to completely dissolve zinc stearate, Tween-20 and sodium stearate to obtain the oil phase;

[0030] (2) Under stirring conditions of 200 r / min, deionized water was added to the oil phase. The system gradually reversed phase and changed from water in oil to oil in water. The viscosity of the system decreased rapidly, and pre-dispersed emulsion A was obtained.

[0031] (3) Under stirring conditions of 200 r / min, starch and sodium metasilicate were added to the pre-dispersed emulsion A to obtain a self-antibacterial and highly stable zinc stearate emulsion.

[0032] Example 2:

[0033] In this example, the zinc stearate emulsion is composed of the following components: 100 parts deionized water, 20 parts zinc stearate, 0.9 parts polyoxyethylene sorbitan monostearate (Tween-60), 0.1 parts potassium stearate, 0.9 parts hydroxymethyl cellulose, 0.1 parts sodium metasilicate, 30 parts stearic acid, and 5 parts propanol.

[0034] The preparation method is as follows:

[0035] (1) Mix stearic acid and propanol, heat to 70°C, keep warm for 5 min, and the stearic acid is completely melted. Under stirring conditions of 150 r / min, add polyoxyethylene dehydrated sorbitol monostearate (Tween-60), potassium stearate and zinc stearate to completely dissolve zinc stearate, Tween-60 and potassium stearate to obtain the oil phase;

[0036] (2) Under stirring conditions of 500 r / min, deionized water was added to the oil phase. The system gradually reversed phase and changed from water in oil to oil in water. The viscosity of the system decreased rapidly, and pre-dispersed emulsion A was obtained.

[0037] (3) Under stirring conditions of 400 r / min, hydroxymethyl cellulose and sodium metasilicate were added to the pre-dispersed emulsion A to obtain a self-antibacterial and highly stable zinc stearate emulsion.

[0038] Example 3:

[0039] In this example, the zinc stearate emulsion is composed of the following components: 100 parts deionized water, 30 parts zinc stearate, 0.8 parts polyoxyethylene sorbitan monooleate (Tween-80), 0.2 parts sodium laurate, 0.8 parts gelatin, 0.2 parts calcium carbonate, 30 parts lauric acid, and 2 parts glycerin.

[0040] The preparation method is as follows:

[0041] (1) Mix lauric acid and glycerin, heat to 50°C, keep warm for 5 min, and lauric acid is completely melted. Under stirring conditions of 180 r / min, add polyoxyethylene sorbitan monooleate (Tween-80), sodium laurate and zinc stearate to completely dissolve zinc stearate, Tween-80 and sodium laurate to obtain the oil phase.

[0042] (2) Under stirring conditions of 700 r / min, deionized water was added to the oil phase. The system gradually reversed phase and changed from water in oil to oil in water. The viscosity of the system decreased rapidly, and pre-dispersed emulsion A was obtained.

[0043] (3) Under stirring conditions of 500 r / min, gelatin and calcium carbonate were added to the pre-dispersed emulsion A to obtain a self-antibacterial and highly stable zinc stearate emulsion.

[0044] Example 4:

[0045] In this example, the zinc stearate emulsion is composed of the following components: 100 parts deionized water, 40 parts zinc stearate, 0.7 parts tetraethylene glycol monostearate (Atlas G-2147), 0.3 parts sodium dodecyl sulfonate (SDS), 0.7 parts xanthan gum, 0.3 parts bentonite, 40 parts lauryl alcohol, and 2 parts ethylene glycol.

[0046] The preparation method is as follows:

[0047] (1) Mix lauryl alcohol and ethylene glycol, heat to 30°C, keep warm for 5 min, and lauryl alcohol is completely melted. Under stirring conditions of 190 r / min, add tetraethylene glycol monostearate (Atlas G-2147), sodium dodecyl sulfonate (SDS), and zinc stearate to completely dissolve zinc stearate, Atlas G-2147, and SDS to obtain the oil phase.

[0048] (2) Under stirring conditions of 900 r / min, deionized water was added to the oil phase. The system gradually reversed phase and changed from water in oil to oil in water. The viscosity of the system decreased rapidly, and pre-dispersed emulsion A was obtained.

[0049] (3) Under stirring conditions of 600 r / min, xanthan gum and bentonite were added to the pre-dispersed emulsion A to obtain a self-antibacterial and highly stable zinc stearate emulsion.

[0050] Example 5:

[0051] In this example, the zinc stearate emulsion is composed of the following components: 100 parts deionized water, 50 parts zinc stearate, 0.3 parts polyethylene glycol monostearate (Pure), 0.7 parts sodium dodecylbenzene sulfonate (SDBS), 0.3 parts gum arabic, 0.7 parts silica, 10 parts butanol, 10 parts glycerin, and 30 parts stearic acid.

[0052] The preparation method is as follows:

[0053] (1) Mix butanol, glycerol and stearic acid, heat to 70°C, and add polyethylene glycol monostearate (Pure), sodium dodecylbenzene sulfonate (SDBS) and zinc stearate under stirring at 200 r / min to completely dissolve zinc stearate, Pure and SDBS to obtain the oil phase;

[0054] (2) Under stirring conditions of 1100 r / min, deionized water was added to the oil phase. The system gradually reversed phase and changed from water in oil to oil in water. The viscosity of the system decreased rapidly, and pre-dispersed emulsion A was obtained.

[0055] (3) Under stirring conditions of 700 r / min, gum arabic and silica were added to the pre-dispersed emulsion A to obtain a self-antibacterial and highly stable zinc stearate emulsion.

[0056] Example 6:

[0057] In this example, the zinc stearate emulsion is composed of the following components: 100 parts deionized water, 30 parts zinc stearate, 0.1 parts sorbitol monolaurate (Span-20), 2 parts sodium dinaphthalenemethane disulfonate (diffuser N), 1 part polyvinyl alcohol, 1 part silica, 10 parts benzene, and 10 parts toluene.

[0058] The preparation method is as follows:

[0059] (1) Mix benzene and toluene, heat to 40°C, keep warm for 5 min, and add sorbitol monolaurate (Span-20), sodium dinaphthalenemethane disulfonate (diffuser N) and zinc stearate under stirring at 200 r / min to completely dissolve zinc stearate, Span-20 and dispersant N to obtain the oil phase;

[0060] (2) Under stirring conditions of 1300 r / min, deionized water was added to the oil phase. The system gradually reversed phase and changed from water in oil to oil in water. The viscosity of the system decreased rapidly, and pre-dispersed emulsion A was obtained.

[0061] (3) Under stirring conditions of 800 r / min, polyvinyl alcohol and silicon dioxide were added to the pre-dispersed emulsion A to obtain a self-antibacterial and highly stable zinc stearate emulsion.

[0062] Example 7:

[0063] In this example, the zinc stearate emulsion is composed of the following components: 100 parts deionized water, 20 parts zinc stearate, 2 parts sorbitan monostearate (Span-60), 2 parts sodium dibutylnaphthalene sulfonate (spreading powder), 1 part polyacrylic acid resin, 1 part bentonite, 5 parts ethanol, and 15 parts toluene.

[0064] The preparation method is as follows:

[0065] (1) Mix ethanol and toluene, heat to 30°C, keep warm for 5 min, and add sorbitol monostearate (Span-60), sodium dibutylnaphthalenesulfonate (spreading powder), and zinc stearate under stirring at 200 r / min to completely dissolve zinc stearate, Span-60, and spreading powder to obtain the oil phase;

[0066] (2) Under stirring conditions of 1700 r / min, deionized water was added to the oil phase. The system gradually reversed phase and changed from water in oil to oil in water. The viscosity of the system decreased rapidly, and pre-dispersed emulsion A was obtained.

[0067] (3) Under stirring conditions of 900 r / min, polyacrylic acid resin and bentonite were added to the pre-dispersed emulsion A to obtain a self-antibacterial and highly stable zinc stearate emulsion.

[0068] Example 8:

[0069] In this example, the zinc stearate emulsion is composed of the following components: 100 parts deionized water, 50 parts zinc stearate, 0.5 parts sorbitan monooleate (Span-80), 1 part sodium dodecyl sulfate (K12), 0.4 parts xanthan gum, 0.2 parts bentonite, 5 parts ethanol, 15 parts ethylene glycol, and 30 parts octadecyl alcohol.

[0070] The preparation method is as follows:

[0071] (1) Mix ethanol, ethylene glycol and octadecanol, heat to 60°C, keep warm for 5 min, and octadecanol is completely melted. Under stirring conditions of 200 r / min, add sorbitol monooleate (Span-80), sodium dodecyl sulfate (K12) and zinc stearate to completely dissolve zinc stearate, Span-80 and K12 to obtain the oil phase;

[0072] (2) Under stirring conditions of 2000 r / min, deionized water was added to the oil phase. The system gradually reversed phase and changed from water in oil to oil in water. The viscosity of the system decreased rapidly, and pre-dispersed emulsion A was obtained.

[0073] (3) Under stirring conditions of 1000 r / min, xanthan gum and bentonite were added to the pre-dispersed emulsion A to obtain a self-antibacterial and highly stable zinc stearate emulsion.

[0074] Example 9:

[0075] In this example, the zinc stearate emulsion is composed of the following components: 100 parts deionized water, 30 parts zinc stearate, 0.6 parts sorbitan monooleate (Span-80), 0.6 parts tetraethylene glycol monostearate (Atlas G-2147), 0.8 parts sodium dodecyl sulfate (K12), 1.0 part xanthan gum, 0.2 parts gelatin, 0.8 parts bentonite, 10 parts ethanol, 10 parts methanol, and 10 parts lauryl alcohol.

[0076] (1) Mix ethanol, methanol and lauryl alcohol, heat to 30°C and keep warm for 5 min. When lauryl alcohol is completely melted, add sorbitol monooleate (Span-80), tetraethylene glycol monostearate (AtlasG-2147), sodium dodecyl sulfate (K12) and zinc stearate under stirring at 190 r / min to completely dissolve zinc stearate, Span-80, AtlasG-2147 and K12 to obtain the oil phase.

[0077] (2) Under stirring conditions of 700 r / min, deionized water was added to the oil phase. The system gradually reversed phase and changed from water in oil to oil in water. The viscosity of the system decreased rapidly, and pre-dispersed emulsion A was obtained.

[0078] (3) Under stirring conditions of 1000 r / min, xanthan gum, gelatin and bentonite were added to the pre-dispersed emulsion A to obtain a self-antibacterial and highly stable zinc stearate emulsion.

[0079] The above examples demonstrate that the process of this invention can be used to prepare an aqueous zinc stearate emulsion with a particle size of 12 μm, a viscosity of 80 cP, high stability, and high antibacterial properties, which has broad application prospects.

[0080] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A self-antibacterial, highly stable zinc stearate emulsion, characterized in that: The product contains the following components: deionized water: 100 parts, zinc stearate: 10-50 parts, emulsifier A: 0.1-2 parts, emulsifier B: 0.1-2 parts, stabilizer A: 0.1-1 part, stabilizer B: 0.1-1 part, and co-emulsifier: 10-50 parts.

2. The self-antibacterial, highly stable zinc stearate emulsion according to claim 1, characterized in that: The co-emulsifier is composed of at least one or more of the following substances that can dissolve zinc stearate: turpentine, stearic acid, octadecanol, lauric acid, lauryl alcohol, benzene, toluene, methanol, ethanol, propanol, butanol, ethylene glycol, glycerin, etc.

3. The self-antibacterial, highly stable zinc stearate emulsion according to claim 1, characterized in that: Emulsifier A is a nonionic surfactant, and emulsifier B is an anionic surfactant. Emulsifier A and emulsifier B are compounded in a ratio of 9:1 to 5:5 to form a composite emulsifier.

4. The self-antibacterial, highly stable zinc stearate emulsion according to claim 1, characterized in that: The emulsifier A is selected from one or more combinations of polyoxyethylene sorbitol monolaurate, polyoxyethylene sorbitol monostearate, polyoxyethylene sorbitol monooleate, tetraethylene glycol monostearate, polyethylene glycol monostearate, fatty alcohol polyoxyethylene ether, sorbitol monolaurate, sorbitol monostearate, and sorbitol monooleate; the emulsifier B is selected from one or more combinations of sodium stearate, potassium stearate, sodium laurate, sodium oleate, sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, sodium dinaphthalene disulfonate, sodium dibutylnaphthalene sulfonate, and sodium dodecyl sulfate.

5. The self-antibacterial, highly stable zinc stearate emulsion according to claim 1, characterized in that: Stabilizer A is an organic stabilizer, and stabilizer B is an inorganic stabilizer. The two are compounded in a ratio of 9:1 to 5:5 to form a composite stabilizer.

6. The self-antibacterial, highly stable zinc stearate emulsion according to claim 1, characterized in that: The stabilizer A is selected from one or more of starch, hydroxymethyl cellulose, gelatin, xanthan gum, gum arabic, polyvinyl alcohol, and polyacrylic acid resin, and the stabilizer B is selected from one or more of sodium metasilicate, calcium carbonate, bentonite, and silicon dioxide.

7. A method for preparing a self-antibacterial, highly stable zinc stearate emulsion according to any one of claims 1-6, characterized in that: Includes the following steps: S1: Heat or melt the co-emulsifier, and add emulsifier A, emulsifier B, and zinc stearate under stirring conditions of 100-200 r / min to completely dissolve the zinc stearate and emulsifier, thus obtaining the oil phase; S2: Under stirring conditions of 200-2000 r / min, deionized water is added to the oil phase. The system gradually reverses phase, and the system changes from water in oil to oil in water. The viscosity of the system decreases rapidly, and pre-dispersed emulsion A is obtained. S3: Under stirring conditions of 200-1000 r / min, stabilizer A and stabilizer B are added to the pre-dispersed emulsion A to obtain a self-antibacterial, highly stable zinc stearate emulsion.

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