Ion-resistant carbomer emulsion and preparation method thereof

Abstract

The invention provides an ion-resistant carbomer emulsion and a preparation method thereof, and relates to the technical field of new material preparation and thickening agents. The ion-resistant Carbomer emulsion comprises a first monomer, a second monomer and a third monomer, the first monomer is an alpha, beta-unsaturated acid monomer, the second monomer is an alpha, beta-unsaturated ester monomer, the structure of the third monomer is # imgabs 0 #, R1 and R2 groups respectively comprise any one of hydrogen and # imgabs 1 #, and R1 and R2 groups respectively comprise any one of hydrogen and # imgabs 1 #. And the third monomer accounts for at least 1% of the total mass of the three monomers. The carbomer emulsion provided by the invention has excellent viscosity and transparency, can maintain excellent viscosity in the presence of salt ions, is environment-friendly and pollution-free, and can meet the requirements of high-end daily chemical products and pharmaceutical industry.

Description

Technical Field

[0001] The invention relates to the technical field of new material preparation and thickener technology, and in particular to an ion-resistant carbomer emulsion and a preparation method thereof. Background Art

[0002] Carbomer resin is a type of high molecular weight polymer with a certain cross-linked structure. Its main component is cross-linked polyacrylic acid or cross-linked polyacrylic acid (ester) macromolecules. Its homopolymer and copolymer swell in water and can form a gel after adding an appropriate amount of alkaline neutralizer, thereby providing excellent stability and thickening properties for the surfactant system. It has the advantages of high stability and good transparency, and is therefore widely used in many fields such as daily chemicals, medical and health care, and personal care products.

[0003] The main polymerization method for producing carbomer resins at present is free radical precipitation polymerization, that is, monomers, initiators, cross-linking agents, etc. are dissolved in an organic solvent, and the monomers are polymerized by thermal initiation. After the molecular weight grows to a certain size, it can no longer dissolve in the solvent and thus precipitates and precipitates in the solvent. The carbomer resin is obtained by solid-liquid separation. For example, patent CN106928398B discloses a method for preparing a medical acrylic thickener; patent CN106866868A discloses a method for preparing a copolymer thickener; patent CN116478324A discloses a method for preparing carbomer. All of the above inventions use acrylic acid (ester) monomers dissolved in a polar solvent to prepare the carbomer resin. Since most of the carbomer resin preparation methods use precipitation polymerization methods under the condition of organic solvent presence, it is inevitable that there will be organic solvent residues in the final product.

[0004] Furthermore, with growing demand in the high-end daily chemical and pharmaceutical markets, the demand for carbomer resins as thickeners in salt ion solutions is also increasing. However, because traditional carbomer resins thicken in aqueous solutions through post-neutralization ionic interactions, the presence of salt ions causes the expanded volume of the carbomer to collapse instantly due to charge interactions, resulting in a sudden drop in viscosity and a failure to achieve a thickening effect.

[0005] To address this problem, the current common solution is to introduce unsaturated long-chain alkyl ester hydrophobic monomers during the synthesis process. By introducing non-ionized long-chain alkyl ester groups, the problems of macromolecular volume collapse and viscosity decrease caused by charge interactions are offset to a certain extent. For example, patent CN117586447A discloses a method for preparing a powder with fast wetting and ion-resistant carbomer; patent CN114195943B discloses a carbomer thickener that can quickly wet and disperse. These preparation methods still inevitably use organic solvents such as petroleum ether and tert-butanol, and cannot achieve a completely green preparation of carbomer. Moreover, such products do not give carbomer salt ion resistance, and its performance in the presence of salt ions still needs to be improved. Summary of the Invention

[0006] In view of the deficiencies in the prior art, the present invention discloses an ion-resistant carbomer emulsion and a preparation method thereof. The preparation method does not require the use of organic solvents and is environmentally friendly. The prepared ion-resistant carbomer emulsion has excellent salt ion tolerance.

[0007] In order to achieve the above technical objectives, on the one hand, the present invention proposes an ion-resistant carbomer emulsion, comprising a first monomer, a second monomer, and a third monomer, wherein the first monomer is an α,β-unsaturated acid monomer, the second monomer is an α,β-unsaturated ester monomer, and the structure of the third monomer is:

[0008] Wherein, R1 and R2 groups include hydrogen, , and the third monomer accounts for at least 1% of the total mass of the three monomers.

[0009] The ion-resistant carbomer emulsion of the present invention adopts unsaturated amide monomers (third monomers) of specific types and contents to polymerize with α,β-unsaturated acid monomers and α,β-unsaturated ester monomers to prepare the carbomer emulsion. The unsaturated amide monomers can enhance the physical cross-linking network through hydrogen bonds during the polymerization process, thereby improving the uniformity and stability of the cross-linking network of the carbomer emulsion, thereby maintaining a high swelling degree in a high-salt environment and improving salt resistance. In addition, the ether bond structure introduced in the unsaturated amide monomers has free rotation and can also change the flexibility of the carbomer molecular chain. The flexible chain segment of the ether bond can be It absorbs local stress concentration caused by ion impact, prevents brittle fracture of the network structure, makes it less likely to shrink in a high-salt environment, and further improves salt resistance. Furthermore, the synergistic effect of the rigid amide bond chelating metal ions and the flexible ether bond encapsulating organic ions enables the carbomer emulsion prepared by the present invention to chelate not only small ions but also large ions, and has the ability to chelate large ions (such as high-valent metal ions) and small ions (such as Na+, Cl-), which can provide multi-dimensional synergistic protection for the application of the carbomer emulsion system in complex ionic environments, thereby having more comprehensive salt resistance.

[0010] Furthermore, the amount of the third monomer is optimized. Optionally, the mass of the third monomer is 1% to 49% of the total mass of the first monomer, the second monomer, and the third monomer, preferably 1% to 25%. This example shows the properties of the carbomer emulsions prepared with different amounts of the third monomer.

[0011] Furthermore, the type and amount of the first monomer are optimized. Optionally, the first monomer includes one or more of acrylic acid, methacrylic acid, itaconic acid, maleic acid, cinnamic acid, and fumaric acid. Optionally, the mass of the first monomer is 50% to 98% of the total mass of the first monomer, the second monomer, and the third monomer.

[0012] Furthermore, the type and amount of the second monomer are optimized. Optionally, the second monomer includes one or more of ethyl acrylate, butyl acrylate, isooctyl acrylate, lauryl acrylate, palmitic acrylate, and stearic acrylate. Optionally, the mass of the second monomer is 1% to 49% of the total mass of the first monomer, the second monomer, and the third monomer.

[0013] Furthermore, the ion-resistant carbomer emulsion also includes a cross-linking agent, an emulsifier and an initiator.

[0014] Furthermore, the cross-linking agent includes one or more of allyl sucrose ether, pentaerythritol allyl ether, diallyl phthalate ether, pentaerythritol triacrylate, phthalic acid diacrylate, and ethylene glycol dimethacrylate.

[0015] Furthermore, the mass of the cross-linking agent is 0.5% to 10% of the total mass of the first monomer, the second monomer and the third monomer.

[0016] Furthermore, the emulsifier includes one or more of sodium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium laurylsulfonate, sodium dibutylnaphthalenesulfonate, ethyl acrylate and sodium stearate.

[0017] Furthermore, the mass of the emulsifier is 0.1% to 3% of the total mass of the first monomer, the second monomer, and the third monomer.

[0018] Furthermore, the initiator includes one or more of potassium sulfate, sodium persulfate, ammonium persulfate, sodium thiosulfate, azobisisobutylamidine hydrochloride and azobisisobutylimidazoline hydrochloride.

[0019] Furthermore, the mass of the initiator is 0.1% to 5% of the total mass of the first monomer, the second monomer and the third monomer.

[0020] On the other hand, the present invention provides a method for preparing an ion-resistant carbomer emulsion, the method comprising the following steps:

[0021] (1) A first monomer, a second monomer, a third monomer, and a cross-linking agent are uniformly mixed in water to obtain a first material; the first monomer is an α,β-unsaturated acid monomer, the second monomer is an α,β-unsaturated ester monomer, and the structure of the third monomer is:

[0022] Wherein, R1 and R2 groups include hydrogen, Any of;

[0023] (2) adding an emulsifier to the first material under mixing conditions to obtain a second material;

[0024] (3) adding an initiator to the second material to carry out a reaction;

[0025] The materials after the reaction are separated to obtain the ion-resistant carbomer emulsion.

[0026] In the above technical solution, a specific unsaturated amide monomer (third monomer) is polymerized with an α,β-unsaturated acid monomer and an α,β-unsaturated ester monomer to prepare a carbomer emulsion. The unsaturated amide monomer can enhance the physical cross-linking network through hydrogen bonds during the polymerization process. When used in combination with a cross-linking agent, the uniformity and stability of the cross-linking network of the carbomer emulsion can be further optimized, thereby maintaining a high swelling degree in a high-salt environment and improving salt tolerance. The ether bond structure in the introduced unsaturated amide monomer has free rotation and can also change the flexibility of the carbomer molecular chain. The flexible chain segment of the ether bond can be It absorbs local stress concentration caused by ion impact, prevents brittle fracture of the network structure, makes it less likely to shrink in a high-salt environment, and further improves salt resistance. Furthermore, the synergistic effect of the rigid amide bond chelating metal ions and the flexible ether bond encapsulating organic ions enables the carbomer emulsion prepared by the present invention to chelate not only small ions but also large ions, and has the ability to chelate large ions (such as high-valent metal ions) and small ions (such as Na+, Cl-), which can provide multi-dimensional synergistic protection for the application of the carbomer emulsion system in complex ionic environments, thereby having more comprehensive salt resistance.

[0027] In addition, in the above technical solution, water is used as the solvent for preparation, and no organic solvent is needed, thereby avoiding the presence of organic solvent residues in the prepared carbomer emulsion, and the overall preparation process is green and environmentally friendly.

[0028] In a further example of the present invention, the mass of the third monomer is 1% to 49% of the total mass of the first monomer, the second monomer and the third monomer, preferably 1% to 25%.

[0029] In a further example of the present invention, the first monomer includes one or more of acrylic acid, methacrylic acid, itaconic acid, maleic acid, cinnamic acid, and fumaric acid.

[0030] In a further example of the present invention, the mass of the first monomer is 50% to 98% of the total mass of the first monomer, the second monomer, and the third monomer.

[0031] In a further example of the present invention, the second monomer includes one or more of ethyl acrylate, butyl acrylate, isooctyl acrylate, lauryl acrylate, palmitic acrylate, and stearic acrylate.

[0032] In a further example of the present invention, the mass of the second monomer is 1% to 49% of the total mass of the first monomer, the second monomer, and the third monomer.

[0033] In a further example of the present invention, the type and amount of the cross-linking agent are optimized. Optionally, the cross-linking agent includes one or more of allyl sucrose ether, pentaerythritol allyl ether, diallyl phthalate, pentaerythritol triacrylate, phthalate diacrylate, and ethylene glycol dimethacrylate. Optionally, the mass of the cross-linking agent is 0.5% to 10% of the total mass of the first monomer, the second monomer, and the third monomer.

[0034] In a further example of the present invention, the total mass of the first monomer, the second monomer, and the third monomer is 25% to 35% of the total mass of the three monomers and water. Optimizing the mass of the polymer monomers relative to the mass of water is beneficial for regulating the solid content of the overall reaction system, improving the efficiency of subsequent reactions, and improving the performance of the carbomer product while reducing production costs. In an optional example of the present invention, the total mass of the first monomer, the second monomer, and the third monomer is 30% of the total mass of the three monomers and water. It should be noted that the three monomers described in the present invention include the first monomer, the second monomer, and the third monomer.

[0035] Optionally, the preparation method of the ion-resistant carbomer emulsion of the present invention is carried out under an inert atmosphere; the inert gas refers to a gas that does not chemically interact with the reactants, such as nitrogen and gases of the zeroth group of the periodic table (such as argon).

[0036] In a further example of the present invention, the type and amount of the emulsifier are optimized. Optionally, the emulsifier includes one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate, sodium dibutylnaphthalene sulfonate, sodium laurate, and sodium stearate. Optionally, the mass of the emulsifier is 0.1% to 3% of the total mass of the first monomer, the second monomer, and the third monomer.

[0037] It should be noted that the mixing conditions in step (2) refer to operating methods that are conducive to mixing the first mixed material with the added emulsifier, such as stirring, shaking, ultrasound, etc., which can be selected by those skilled in the art as needed; in an optional example of the present invention, step (2) is carried out under stirring conditions.

[0038] There is no limitation on the method of adding the emulsifier in step (2), and the existing method of adding the emulsifier to the preparation system can be adopted; in an optional example of the present invention, the emulsifier is added to the first material by dropwise addition.

[0039] Optionally, the particle size of the organic phase in the second material is 50 to 300 μm. By controlling the particle size of the particles in the organic phase in the second material within a smaller range, a synergistic effect can be produced with the thickening and stabilizing properties of carbomer, significantly improving the performance and function of the emulsion. It is understandable that the organic phase in the second material is in the form of droplets (oil droplets), and the size of the particle size in the organic phase is almost the same as the size of the particle size in the final carbomer emulsion. In the specific process, the control of the particle size is achieved by combining the stirring speed of the control system and the addition speed of the emulsifier; and the size of the droplet particle size can be optionally monitored by an instrument or device such as an online laser particle size analyzer.

[0040] In a further embodiment of the present invention, step (3) is performed at a gradient temperature, including adding an initiator to react at a first temperature and maintaining the temperature, and then heating to a second temperature. By performing the cross-linking reaction of the polymer monomers at a gradient temperature, the reaction can be performed at an optimal temperature, thereby regulating the growth rate of the polymer chain, controlling the molecular weight and distribution of the polymer, and further improving the physical and chemical properties of the resulting carbomer emulsion, such as improving its thermal stability, mechanical strength, and chemical resistance.

[0041] Optionally, the first temperature is 50-80° C.; further optionally, the insulation time under the first temperature condition is 1-4 hours.

[0042] Optionally, the second temperature is 70-90° C.; further optionally, the insulation time under the second temperature condition is 4-10 hours.

[0043] In a further example of the present invention, the type and amount of the initiator are optimized. Optionally, the initiator includes one or more of potassium sulfate, sodium persulfate, ammonium persulfate, sodium thiosulfate, azobisisobutylamidine hydrochloride, and azobisisobutylimidazoline hydrochloride. Optionally, the mass of the initiator is 0.1% to 5% of the total mass of the first monomer, the second monomer, and the third monomer.

[0044] It should be noted that the separation operation is an operation to remove excess water from the reacted material, and those skilled in the art can select it according to their needs in the specific process. In an optional example of the present invention, the material after the reaction in step (3) is centrifuged and filtered to obtain the target carbomer emulsion.

[0045] Compared with the prior art, the present invention has the following beneficial effects: the carbomer emulsion of the present invention has excellent viscosity and transparency, maintains excellent viscosity even in the presence of salt ions, is environmentally friendly and pollution-free, and can meet the needs of the high-end daily chemical products and pharmaceutical industries. The preparation method of the ion-resistant carbomer emulsion of the present invention uses α,β-unsaturated acid monomers, α,β-unsaturated ester monomers, and unsaturated amide monomers of a specific structure as raw materials to prepare the carbomer emulsion, which can significantly improve the salt tolerance of the prepared carbomer emulsion and maintain excellent viscosity even in the presence of salt ions. The entire preparation process does not require the use of organic solvents, making it environmentally friendly. DETAILED DESCRIPTION

[0046] To facilitate understanding of the present invention, the present invention will be described in more detail below, with preferred embodiments of the present invention provided. However, it should be understood that these embodiments are merely for the purpose of further explanation and are not to be construed as limiting the present invention in any form, i.e., they are not intended to limit the scope of protection of the present invention.

[0047] Unless otherwise defined, the technical terms used in the following examples have the same meanings as commonly understood by those skilled in the art to which this invention belongs. The experimental reagents used in the following examples, unless otherwise specified, are conventional biochemical reagents; the experimental methods described, unless otherwise specified, are conventional methods.

[0048] The properties of the carbomer emulsions of the embodiments of the present invention and the comparative examples were tested using the following test methods:

[0049] Test method 1: Light transmittance test in aqueous solution at 0.5% concentration

[0050] Accurately weigh 590 g of water into a 1000 mL beaker and place it in a 25° C. incubator. Add 10 g of the polymer emulsion to the water and stir evenly. Then, add 4-5 g of an 18% mass concentration sodium hydroxide aqueous solution to the solution while stirring to neutralize the polymer, and adjust the pH of the resulting hydrogel to 7.0-7.8. The hydrogel is then transferred to a centrifuge tube and defoamed by centrifugation at 5000 rpm for 30 minutes. The transmittance of the gel at 420 nm is measured at 25° C. using a Shimadzu UV-1800 ultraviolet spectrophotometer.

[0051] Test method 2: Viscosity test in aqueous solution at 0.5% concentration

[0052] Accurately weigh 590 g of water into a 1000 mL beaker, place it in a 25° C. thermostat, add 10 g of the polymer emulsion to the water and stir evenly, then add 4-5 g of an 18% mass concentration sodium hydroxide aqueous solution to the solution while stirring to neutralize the polymer, and adjust the pH of the resulting hydrogel to 7.0-7.8; then transfer the hydrogel to a centrifuge tube and centrifuge at 5000 rpm for 30 minutes for defoaming treatment; measure the viscosity of the hydrogel using a Brookfield DV2T-RV rotational viscometer at 25° C., and select a speed of 20 rpm.

[0053] Test method 3: Viscosity test at 0.1% sodium chloride solution salt ion concentration

[0054] Accurately weigh 580g of water into a 1000mL beaker, place it in a constant temperature box at 25°C, add 10g of the polymer emulsion to the water and stir evenly, then add 4-5g of an 18% mass concentration sodium hydroxide aqueous solution to the solution while stirring to neutralize the polymer, and adjust the pH of the resulting hydrogel to 7.0-7.8; then, add 10g of a 6% mass fraction sodium chloride aqueous solution dropwise into the water while stirring, stir evenly, transfer the hydrogel to a centrifuge tube, and centrifuge at 5000rpm for 30min for defoaming treatment; use a Brookfield DV2T-RV rotational viscometer at 25°C to measure the viscosity of the hydrogel, and select a speed of 20 rpm.

[0055] Test method 4: Viscosity test at 0.5% sodium chloride solution salt ion concentration

[0056] Accurately weigh 580g of water into a 1000mL beaker, place it in a constant temperature box at 25°C, add 10g of the polymer emulsion to the water and stir evenly, then add 4-5g of an 18% mass concentration sodium hydroxide aqueous solution to the solution while stirring to neutralize the polymer, and adjust the pH of the resulting hydrogel to 7.0-7.8; then, dropwise add 10g of a 30% mass fraction sodium chloride aqueous solution into the water while stirring, stir evenly, transfer the hydrogel to a centrifuge tube, and centrifuge at 5000rpm for 30min for defoaming treatment; use a Brookfield DV2T-RV rotational viscometer at 25°C to measure the viscosity of the hydrogel, and select a speed of 20 rpm.

[0057] Test Method 5: Viscosity Test at 0.1% Calcium Chloride Solution Salt Ion Concentration

[0058] Accurately weigh 580g of water into a 1000mL beaker, place it in a constant temperature box at 25°C, add 10g of the polymer emulsion to the water and stir evenly, then add 4-5g of an 18% mass concentration sodium hydroxide aqueous solution to the solution while stirring to neutralize the polymer, and adjust the pH of the resulting hydrogel to 7.0-7.8; then, dropwise add 10g of a 6% mass fraction calcium chloride aqueous solution into the water while stirring, stir evenly, transfer the hydrogel to a centrifuge tube, and centrifuge at 5000rpm for 30min for defoaming treatment; measure the viscosity of the hydrogel using a Brookfield DV2T-RV rotational viscometer at 25°C, and select a speed of 20 rpm.

[0059] Test Method 6: Viscosity Test at 0.1% Ferric Chloride Solution Salt Ion Concentration

[0060] Accurately weigh 580g of water into a 1000mL beaker, place it in a constant temperature box at 25°C, add 10g of the polymer emulsion to the water and stir evenly, then add 4-5g of an 18% mass concentration sodium hydroxide aqueous solution to the solution while stirring to neutralize the polymer, and adjust the pH of the resulting hydrogel to 7.0-7.8; then, add 10g of a 30% mass fraction calcium chloride aqueous solution dropwise into the water while stirring, stir evenly, transfer the hydrogel to a centrifuge tube, and centrifuge at 5000rpm for 30min for defoaming treatment; use a Brookfield DV2T-RV rotational viscometer at 25°C to measure the viscosity of the hydrogel, and select a speed of 20 rpm.

[0061] Example 1

[0062] To a 2000mL three-necked flask, add 700g of water, 150g of acrylic acid, 75g of ethyl acrylate, 75g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(acetamidomethyl), and 30g of allyl sucrose ether in sequence. Stir thoroughly at 200 rpm, and then add 9g of sodium lauryl sulfate dropwise. At this point, the organic phase particle size is 150 microns. The reaction temperature is raised to 50°C, and 15g of potassium persulfate is added to the reaction system. The temperature is then raised to 70°C and maintained for 4 hours. After the reaction is complete, the product is centrifuged, and the aqueous phase is filtered to obtain the final product. In this embodiment, the light transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a sodium chloride salt ion concentration of 0.1%, the viscosity at a sodium chloride salt ion concentration of 0.5%, the viscosity at a calcium chloride salt ion concentration of 0.1%, and the viscosity at a ferric chloride salt ion concentration of 0.1% were tested respectively. The test results are shown in Table 1.

[0063] Example 2

[0064] To a 2000mL three-necked flask, add 700g of water, 150g of acrylic acid, 3g of ethyl acrylate, 147g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(acetamidomethyl), and 30g of allyl sucrose ether in sequence. Stir thoroughly at 200 rpm, and then add 9g of sodium lauryl sulfate dropwise. At this point, the organic phase particle size is 150 microns. The reaction temperature is raised to 50°C, and 15g of potassium persulfate is added to the reaction system. The temperature is then raised to 70°C and maintained for 4 hours. After the reaction is complete, the product is centrifuged, and the aqueous phase is filtered to obtain the final product. In this embodiment, the light transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a sodium chloride salt ion concentration of 0.1%, the viscosity at a sodium chloride salt ion concentration of 0.5%, the viscosity at a calcium chloride salt ion concentration of 0.1%, and the viscosity at a ferric chloride salt ion concentration of 0.1% were tested respectively. The test results are shown in Table 1.

[0065] Example 3

[0066] To a 2000 mL three-necked flask, 550 g of water, 100 g of itaconic acid, 100 g of maleic acid, 75 g of isooctyl acrylate, 25 g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(N-benzyl-N-phenylacetamide), and 10 g of diallyl phthalate were added sequentially. The mixture was stirred thoroughly at 250 rpm, and 1 g of sodium dodecylsulfonate was added dropwise. At this point, the organic phase had a particle size of 120 μm. The reaction temperature was raised to 70°C, and 5 g of ammonium persulfate was added to the reaction system. The temperature was then raised to 80°C and maintained for 10 hours. After the reaction, the product was centrifuged, and the aqueous phase was filtered to obtain the final product. In this embodiment, the light transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a sodium chloride salt ion concentration of 0.1%, the viscosity at a sodium chloride salt ion concentration of 0.5%, the viscosity at a calcium chloride salt ion concentration of 0.1%, and the viscosity at a ferric chloride salt ion concentration of 0.1% were tested respectively. The test results are shown in Table 1.

[0067] Example 4

[0068] To a 2000mL three-necked flask, add 900g of water, 294g of fumaric acid, 3g of stearic acrylate, 3g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(N,N-dibenzylacetamide), and 1.5g of pentaerythritol triacrylate in sequence. Stir thoroughly at 180r / min, and then add 0.3g of sodium dibutylnaphthalenesulfonate dropwise. At this point, the organic phase particle size is 200 microns. The reaction temperature is raised to 80°C, and 0.3g of sodium thiosulfate is added to the reaction system. The temperature is then raised to 90°C and maintained for 8 hours. After the reaction is complete, the product is centrifuged, and the aqueous phase is filtered to obtain the final product. In this embodiment, the light transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a sodium chloride salt ion concentration of 0.1%, the viscosity at a sodium chloride salt ion concentration of 0.5%, the viscosity at a calcium chloride salt ion concentration of 0.1%, and the viscosity at a ferric chloride salt ion concentration of 0.1% were tested respectively. The test results are shown in Table 1.

[0069] Example 5

[0070] To a 2000mL three-necked flask, add 700g of water, 220g of cinnamic acid, 5g of acrylate palmitate, 75g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(N-benzylacetamide), and 15g of phthalic acid diacrylate in sequence. Stir thoroughly at 300 rpm, and then add 3g of sodium laurate dropwise. At this point, the organic phase particle size is 100 microns. The reaction temperature is raised to 65°C, and 5g of azobisisobutylamidine hydrochloride is added to the reaction system. The temperature is then raised to 80°C and maintained for 9 hours. After the reaction is complete, the product is centrifuged, and the aqueous phase is filtered to obtain the final product. In this embodiment, the light transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a sodium chloride salt ion concentration of 0.1%, the viscosity at a sodium chloride salt ion concentration of 0.5%, the viscosity at a calcium chloride salt ion concentration of 0.1%, and the viscosity at a ferric chloride salt ion concentration of 0.1% were tested respectively. The test results are shown in Table 1.

[0071] Example 6

[0072] To a 2000mL three-necked flask, 700g of water, 150g of itaconic acid, 147g of lauryl acrylate, 3g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(N-phenylacetamide), and 20g of ethylene glycol dimethacrylate were added sequentially. The mixture was stirred thoroughly at 350r / min, and 7g of sodium stearate was added dropwise. At this point, the organic phase particle size was 50 microns. The reaction temperature was then raised to 50°C, and 6g of azobisisobutylimidazoline hydrochloride was added to the reaction system. The temperature was then raised to 75°C and maintained for 5 hours. After the reaction, the product was centrifuged, and the aqueous phase was filtered to obtain the final product. In this embodiment, the light transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a sodium chloride salt ion concentration of 0.1%, the viscosity at a sodium chloride salt ion concentration of 0.5%, the viscosity at a calcium chloride salt ion concentration of 0.1%, and the viscosity at a ferric chloride salt ion concentration of 0.1% were tested respectively. The test results are shown in Table 1.

[0073] Comparative Example 1

[0074] In a 2000mL three-necked flask, 700g of water, 150g of acrylic acid, 75g of ethyl acrylate and 30g of allyl sucrose ether were added in sequence, stirred thoroughly at 200r / min, and 9g of sodium lauryl sulfate was added dropwise. At this time, the organic phase particle size was 150 microns. The reaction temperature was then raised to 50°C, 15g of potassium persulfate was added to the reaction system, and the mixture was kept warm for 1 hour; the system temperature was then raised to 70°C and kept warm for 4 hours. After the reaction was completed, the product was centrifuged, the aqueous phase was taken and filtered to obtain the final product. This example tested the transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a 0.1% sodium chloride salt ion concentration, the viscosity at a 0.5% sodium chloride salt ion concentration, the viscosity at a 0.51% calcium chloride salt ion concentration, and the viscosity at a 0.1% ferric chloride salt ion concentration. The test results are shown in Table 1.

[0075] Comparative Example 2

[0076] In a 2000mL three-necked flask, 700g of water, 150g of acrylic acid, 75g of ethyl acrylate, 75g of acrylamide and 30g of allyl sucrose ether were added in sequence, stirred thoroughly at 200r / min, and 9g of sodium lauryl sulfate was added dropwise. At this time, the organic phase particle size was 150 microns. The reaction temperature was then raised to 50°C, 15g of potassium persulfate was added to the reaction system, and the temperature was kept warm for 1 hour; the system temperature was then raised to 70°C and kept warm for 4 hours. After the reaction was completed, the product was centrifuged, the aqueous phase was taken and filtered to obtain the final product. This example tested the transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a 0.1% sodium chloride salt ion concentration, the viscosity at a 0.5% sodium chloride salt ion concentration, the viscosity at a 0.51% calcium chloride salt ion concentration, and the viscosity at a 0.1% ferric chloride salt ion concentration. The test results are shown in Table 1.

[0077] Comparative Example 3

[0078] In a 2000mL three-necked flask, 700g of water, 150g of acrylic acid, 75g of ethyl acrylate, and 75g of (E)-oct-4-ene-1,8-diamide were added in sequence, stirred thoroughly at 200r / min, and 9g of sodium lauryl sulfate was added dropwise. At this time, the organic phase particle size was 150 microns. The reaction temperature was then raised to 50°C and kept warm for 1 hour; the system temperature was then raised to 70°C and kept warm for 4 hours. After the reaction was completed, the product was centrifuged, the aqueous phase was taken and filtered to obtain the final product. This example tested the transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a 0.1% sodium chloride salt ion concentration, the viscosity at a 0.5% sodium chloride salt ion concentration, the viscosity at a 0.51% calcium chloride salt ion concentration, and the viscosity at a 0.1% ferric chloride salt ion concentration. The test results are shown in Table 1.

[0079] Comparative Example 4

[0080] In a 2000mL three-necked flask, 700g of water, 150g of acrylic acid, 75g of ethyl acrylate, 75g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(acetamidomethyl), 30g of allyl sucrose ether, and 9g of sodium lauryl sulfate were added in sequence and stirred thoroughly at 200r / min. The organic phase particle size was 350 microns. The reaction temperature was then raised to 50°C and kept warm for 1 hour; the system temperature was then raised to 70°C and kept warm for 4 hours. After the reaction was completed, the product was centrifuged, the aqueous phase was taken and filtered to obtain the final product. In this example, the transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a 0.1% sodium chloride salt ion concentration, the viscosity at a 0.5% sodium chloride salt ion concentration, the viscosity at a 0.51% calcium chloride salt ion concentration, and the viscosity at a 0.1% ferric chloride salt ion concentration were tested respectively. The test results are shown in Table 1.

[0081] Comparative Example 5

[0082] To a 2000mL three-necked flask, add 700g of water, 150g of acrylic acid, 75g of ethyl acrylate, 75g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(acetamidomethyl), and 30g of allyl sucrose ether in sequence. Stir thoroughly at 40 rpm, and then add 9g of sodium lauryl sulfate dropwise. At this point, the organic phase particle size is 350 microns. The reaction temperature is then raised to 50°C, and 15g of potassium persulfate is added to the reaction system. The temperature is then raised to 70°C and maintained for 4 hours. After the reaction is complete, the product is centrifuged, and the aqueous phase is filtered to obtain the final product. In this embodiment, the light transmittance of the obtained resin emulsion in a 0.5% pure water system, the viscosity in a 0.5% pure water system, the viscosity at a sodium chloride ion concentration of 0.1%, the viscosity at a sodium chloride ion concentration of 0.5%, the viscosity at a calcium chloride ion concentration of 0.51%, and the viscosity at a ferric chloride ion concentration of 0.1% were tested respectively. The test results are shown in Table 1.

[0083] Comparative Example 6

[0084] In a 2000mL three-necked flask, 700g of water, 150g of acrylic acid, 75g of ethyl acrylate, 75g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(acetamidomethyl) and 30g of allyl sucrose ether were added in sequence, stirred thoroughly at 200r / min, and 9g of sodium lauryl sulfate was added dropwise. At this time, the organic phase particle size was 150 microns, and the system temperature was then raised to 70°C and kept warm for 5 hours. After the reaction was completed, the product was centrifuged, the aqueous phase was taken and filtered to obtain the final product. This embodiment tested the transmittance of the obtained resin emulsion in a 0.5% concentration pure water system, the viscosity in a 0.5% concentration pure water system, the viscosity at 0.1% sodium chloride salt ion concentration, the viscosity at 0.5% sodium chloride salt ion concentration, the viscosity at 0.51% calcium chloride salt ion concentration, and the viscosity at 0.1% ferric chloride salt ion concentration. The test results are shown in Table 1.

[0085] Comparative Example 7

[0086] In a 2000mL three-necked flask, 700g of water, 150g of acrylic acid, 75g of ethyl acrylate, 75g of (E)-2,2'-(ethylene-1,2-diylbis(oxy))bis(acetamidomethyl) and 30g of allyl sucrose ether were added in sequence, stirred thoroughly at 200r / min, and 9g of sodium lauryl sulfate was added dropwise. At this time, the organic phase particle size was 150 microns, and the system temperature was then raised to 50°C and kept warm for 5 hours. After the reaction was completed, the product was centrifuged, the aqueous phase was taken and filtered to obtain the final product. This embodiment tested the transmittance of the obtained resin emulsion in a 0.5% concentration pure water system, the viscosity in a 0.5% concentration pure water system, the viscosity at 0.1% sodium chloride salt ion concentration, the viscosity at 0.5% sodium chloride salt ion concentration, the viscosity at 0.51% calcium chloride salt ion concentration, and the viscosity at 0.1% ferric chloride salt ion concentration. The test results are shown in Table 1.

[0087] Table 1

[0088]

[0089] As demonstrated by Examples 1-6 in Table 1, the ion-resistant carbomer emulsion of the present invention exhibits excellent light transmittance and viscosity, is tolerant to a variety of ions, particularly divalent and higher ions, and exhibits relatively stable viscosity under conditions of 0.1% to 0.5% sodium chloride, 0.1% calcium chloride, and 0.1% ferric chloride, demonstrating a stable and effective thickening effect. Example 1 and Comparative Examples 1-3 demonstrate that the addition of a third monomer with a specific structure during the preparation of the ion-resistant carbomer emulsion of the present invention significantly enhances the salt ion tolerance of the resulting carbomer emulsion. Example 1 and Comparative Example 4 demonstrate that the addition of an emulsifier in a specific step during the preparation of the ion-resistant carbomer emulsion of the present invention effectively controls the particle size of the organic phase in the resulting carbomer emulsion, improving product uniformity and, consequently, light transmittance. Furthermore, Example 1 and Comparative Example 5 demonstrate that controlling the particle size of the organic phase in the second material during the preparation of the ion-resistant carbomer emulsion of the present invention helps improve the light transmittance of the resulting product. By comparing Example 1 with Comparative Examples 6 to 7, it is confirmed that carrying out step (3) at a gradient temperature can improve the viscosity and ion tolerance of the prepared carbomer emulsion.

[0090] It should be noted that the above is a further detailed description of the present invention in conjunction with specific embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, several simple improvements can be made without departing from the concept of the present invention, and all of these should be considered to fall within the scope of protection of the present invention.

Claims

1. An ion-resistant carbomer emulsion, characterized in that: It includes a first monomer, a second monomer, and a third monomer, wherein the first monomer is an α,β-unsaturated acid monomer, the second monomer is an α,β-unsaturated ester monomer, and the structure of the third monomer is: Wherein, R1 and R2 groups include hydrogen, , and the third monomer accounts for at least 1% of the total mass of the three monomers.

2. The ion-resistant carbomer emulsion according to claim 1, wherein The mass of the third monomer is 1% to 49% of the total mass of the first monomer, the second monomer and the third monomer, preferably 1% to 25%; Preferably, the first monomer comprises one or more of acrylic acid, methacrylic acid, itaconic acid, maleic acid, cinnamic acid and fumaric acid; and / or the mass of the first monomer is 50% to 98% of the total mass of the first monomer, the second monomer and the third monomer; Preferably, the second monomer includes one or more of ethyl acrylate, butyl acrylate, isooctyl acrylate, lauryl acrylate, palmitic acrylate and stearic acrylate; and / or the mass of the second monomer is 1% to 49% of the total mass of the first monomer, the second monomer and the third monomer.

3. A method for preparing an ion-resistant carbomer emulsion, characterized in that: The following steps are involved: (1) A first monomer, a second monomer, a third monomer, and a cross-linking agent are uniformly mixed in water to obtain a first material; the first monomer is an α,β-unsaturated acid monomer, the second monomer is an α,β-unsaturated ester monomer, and the structure of the third monomer is: Wherein, R1 and R2 groups include hydrogen, Any of; (2) adding an emulsifier to the first material under mixing conditions to obtain a second material; (3) adding an initiator to the second material to carry out a reaction; The materials after the reaction are separated to obtain the ion-resistant carbomer emulsion.

4. The preparation method of the ion-resistant carbomer emulsion according to claim 3, wherein The mass of the third monomer is 1% to 49% of the total mass of the first monomer, the second monomer and the third monomer, preferably 1% to 25%.

5. The preparation method of the ion-resistant carbomer emulsion according to claim 3, wherein The first monomer includes one or more of acrylic acid, methacrylic acid, itaconic acid, maleic acid, cinnamic acid and fumaric acid; and / or, the mass of the first monomer is 50% to 98% of the total mass of the first monomer, the second monomer, and the third monomer; and / or, the second monomer comprises one or more of ethyl acrylate, butyl acrylate, isooctyl acrylate, lauryl acrylate, palmitic acrylate and stearic acrylate; And / or, the mass of the second monomer is 1% to 49% of the total mass of the first monomer, the second monomer and the third monomer.

6. The preparation method of the ion-resistant carbomer emulsion according to claim 4, wherein The cross-linking agent includes one or more of allyl sucrose ether, pentaerythritol allyl ether, diallyl phthalate ether, pentaerythritol triacrylate, phthalic acid diacrylate, and ethylene glycol dimethacrylate; And / or, the mass of the cross-linking agent is 0.5% to 10% of the total mass of the first monomer, the second monomer and the third monomer.

7. The preparation method of the ion-resistant carbomer emulsion according to claim 3, wherein In the step (1), the total mass of the first monomer, the second monomer and the third monomer is 25% to 30% of the total mass of the three monomers and water.

8. The preparation method of the ion-resistant carbomer emulsion according to claim 3, wherein The emulsifier includes one or more of sodium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium laurylsulfonate, sodium dibutylnaphthalenesulfonate, ethyl acrylate and sodium stearate; And / or, the mass of the emulsifier is 0.1% to 3% of the total mass of the first monomer, the second monomer, and the third monomer; Preferably, the particle size of the organic phase in the second material is 50 to 300 μm.

9. The preparation method of the ion-resistant carbomer emulsion according to claim 3, wherein The step (3) is performed at a gradient temperature, comprising adding an initiator to react at a first temperature and keeping the temperature, and then heating to a second temperature; Preferably, the first temperature is 50-80°C, and / or the second temperature is 70-90°C; Further preferably, the holding time under the first temperature condition is 1 to 4 hours; and / or the holding time under the second temperature condition is 4 to 10 hours.

10. The method for preparing the ion-resistant carbomer emulsion according to claim 3, wherein: The initiator includes one or more of potassium sulfate, sodium persulfate, ammonium persulfate, sodium thiosulfate, azobisisobutylamidine hydrochloride and azobisisobutylimidazoline hydrochloride; And / or, the mass of the initiator is 0.1% to 5% of the total mass of the first monomer, the second monomer and the third monomer.

Images