Powder carbomer polymer as well as preparation method and application thereof

Abstract

The invention relates to the technical field of organic synthesis, in particular to a powder carbomer polymer as well as a preparation method and application thereof. According to the invention, raw materials are limited, especially the component (3) and the component (4) are cooperatively used, so that the interior of the carbomer particles can be subjected to primary crosslinking during polymerization of the component (3), and also can be subjected to secondary crosslinking through reaction of epoxy groups in the component (4) and carboxyl on the surface of powder carbomer when the component (4) is dried; a powder carbomer polymer of a double-crosslinking network is formed; by using the component (2), the association effect of the carbomer chain segment and other substances in the system can be effectively improved, so that the yield value of the formed system is larger. In the subsequent use process, hydrogen bonds among particles are changed into covalent bonds after neutralization, water absorption, swelling and extrusion, so that the deformation resistance of the swollen particles and the sliding among the particles are improved, and the suspension property of the particles in the formula, especially the high-temperature suspension property at 50 DEG C or above, is improved.

Description

Technical Field

[0001] This application relates to the field of organic synthesis technology, specifically to a powdered carbomer polymer, its preparation method, and its application. Background Technology

[0002] Powdered carbomer, a homopolymer or copolymer of acrylic acid, is a very important rheology modifier. Neutralized carbomer forms an excellent gel matrix with superior thickening, suspending, and emulsifying properties, and is widely used in personal care products, particularly bath liquids, skin creams, toothpaste, shampoos, and hairsprays. For example, existing technologies disclose copolymers formed by acrylic acid and polyolefin polyether crosslinking agents, which can absorb large amounts of water, significantly increasing their volume. Existing technologies also disclose polymers formed by unsaturated carboxylic acids and at least one acrylate or methacrylate whose alkyl group contains 1-30 carbon atoms; these polymers can also serve as effective rheology modifiers. Furthermore, numerous publications disclose methods for using powdered carbomer as rheology modifiers, which are well-known techniques in the field.

[0003] The suspension of particulate and insoluble materials in personal care compositions, essential for activity and aesthetics, is increasingly welcomed by formulators. However, differences in compatibility or density between particulate or insoluble materials and the formulation can lead to product stability issues such as particle separation from the continuous phase, stratification, or precipitation. For example, maintaining the suspension of high-density, large particles such as physical sunscreens (titanium dioxide, zinc oxide), mineral pigments, and abrasive particles (mica flakes, nut shell powder), as well as high concentrations of oil phases and longer suspension durations, remains a significant challenge. Therefore, for commonly used rheology modifier powders like carbomer, the ability to stabilize suspended particulates and / or other water-insoluble materials, in addition to providing the necessary rheological properties, is highly desirable in the personal care composition field. Summary of the Invention

[0004] This application provides a powdered carbomer polymer, its preparation method, and its application, in order to solve the problem that the suspension stability of carbomer for high-density large particles or insoluble materials still needs to be improved in the prior art.

[0005] In a first aspect, this application provides a powdered carbomer polymer, the raw materials of which include: Component (1) is an olefinic unsaturated carboxylic acid monomer; Component (2) is an olefinic unsaturated monomer that is different from component (1) but can be copolymerized with it; Component (3) contains a crosslinked monomer with at least two olefinic unsaturated groups; Component (4) is an aliphatic polyol glycidyl ether crosslinker containing at least two glycidyl ether groups; Among them, the mass percentage of component (4) is 0.01%-0.5% based on the total mass of components (1), (2), (3), and (4).

[0006] As an example, the mass percentage of component (4) can be 0.01%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.4%, 0.5%, or within any of the above values. If the amount of component (4) is lower than the above-defined range, a double cross-linked network structure cannot be effectively formed, which is not conducive to suspension stability. The amount of component (4) should not be too much. If it exceeds the above-defined range, it will lead to excessive cross-linking, which will prevent the formed carbomer structure from swelling sufficiently during use, reduce its thickening efficiency, and affect suspension stability.

[0007] In an optional embodiment, the component (4) includes at least one of polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,2-cyclohexanediol diglycidyl ether, glycerol triglycidyl ether, and pentaerythritol tetraglycidyl ether. And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of component (4) is 0.1%-0.25%.

[0008] In one alternative embodiment, component (1) comprises acrylic acid; And / or, the component (1) comprises acrylic acid and a C4-C6 carboxylic acid containing a double bond; Optionally, the C4-C6 carboxylic acids containing double bonds include at least one of maleic acid, itaconic acid, fumaric acid, methacrylic acid, crotonic acid, and aconitic acid.

[0009] In an optional embodiment, component (2) comprises an alkyl (meth)acrylate having the following chemical formula: CH2=CR1-COOR; Wherein, R includes a straight-chain or branched alkyl group having at least 1 to 30 carbon atoms, and R1 is selected from hydrogen or methyl; Optionally, the component (2) includes at least one of the following: decyl acrylate, isodecyl acrylate, lauryl acrylate, stearate acrylate, docosyl acrylate, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, decyl methacrylate, isodecyl methacrylate, lauryl acrylate, stearate methacrylate, docosyl methacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, octyl methacrylate, and 2-ethylhexyl methacrylate. And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of component (2) is 1%-10%, optionally 3%-7%.

[0010] As an example, the mass percentage of component (2) may be 1%, 5%, 4%, 5%, 6%, 7%, 9%, 10%, or within any of the above values.

[0011] In an optional embodiment, the component (3) comprises a polyfunctional acrylate with at least two polymerizable olefinic unsaturated double bonds and / or a polychain alkenyl ether containing at least two polymerizable olefinic unsaturated double bonds; optionally, it comprises one or more of allyl pentaerythritol, allyl sucrose, allyl acrylate, and trimethylolpropane diallyl ether. And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of component (3) is 0.01%-2%, optionally 0.1%-1.5%, and more preferably 0.5%-1%.

[0012] As an example, the mass percentage of component (3) may be 0.01%, 0.05%, 0.1%, 0.3%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, or within any of the above values.

[0013] Secondly, a method for preparing the above-mentioned powdered carbomer polymer is provided, comprising: Components (1), (2), (3), and (4) were polymerized in a solvent and then dried.

[0014] In one alternative embodiment, the polymerization reaction includes the following steps: S1, the components (1), (2), (3), and the first free radical initiator are subjected to a first reaction in a solvent; S2, with the addition of a second free radical initiator, proceeds to the second reaction; The timing of adding component (4) is as follows: adding it together with component (1), adding it during the first or second reaction, adding it after the first or second reaction; optionally, adding it after the second reaction.

[0015] In one optional embodiment, the temperature of the first reaction is 40-70°C, and the reaction time is 3-8 hours. As an example, the temperature of the first reaction can be 40°C, 50°C, 60°C, 70°C, or any of the above values; the reaction time can be 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, or any of the above values.

[0016] And / or, the temperature of the second reaction is 40-70°C, and the reaction time is 1-3h; as an example, the temperature of the second reaction can be 40°C, 50°C, 60°C, 70°C, or within any range of the above values; the reaction time can be 1h, 1.5h, 2h, 2.5h, 3h, or within any range of the above values.

[0017] And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of the first free radical initiator is 0.05%-2%; And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of the second free radical initiator is 0.02%-1%; As an example, the amount of the first free radical initiator may be 0.05%, 0.1%, 0.3%, 0.5%, 0.8%, 1%, 1.3%, 1.5%, 1.7%, 2%, or within any of the above values; the amount of the second free radical initiator may be 0.02%, 0.05%, 0.1%, 0.3%, 0.5%, 0.7%, 0.9%, 1%, or within any of the above values.

[0018] And / or, the drying temperature is 90-120℃, and the drying time is 2-12 hours.

[0019] In one optional embodiment, the amount of solvent used is 83%-92% based on the total mass of components (1), (2), (3), (4) and solvent being 100%; as an example, the amount of solvent used can be 83%, 85%, 87%, 98%, 90%, 92%, or within any of the above values.

[0020] And / or, the solvent includes at least one of hydrocarbons containing 6-40 carbon atoms, carbon halogenates containing 6-40 carbon atoms, chlorinated hydrocarbons containing 6-40 carbon atoms, esters containing 6-40 carbon atoms, and ketones containing 6-40 carbon atoms; as an example, the solvent includes at least one of benzene, toluene, xylene, pentane, hexane, octane, cyclopentane, cyclohexane, cyclooctane, dichloromethane, chloroform, dichloroethane, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, methyl ethyl ketone, and cyclohexanone.

[0021] Optionally, the solvent is a mixture of cyclohexane and ethyl acetate; further optionally, the mass ratio of cyclohexane to ethyl acetate is 1:9 to 9:1; as an example, the mass ratio of cyclohexane to ethyl acetate can be 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2, 9:1, or within any of the above values.

[0022] And / or, the first free radical initiator and the second free radical initiator independently include at least one of organic peroxide compounds and azo compounds.

[0023] Thirdly, the application of the above-mentioned powdered carbomer polymer or the powdered carbomer polymer prepared by the above-mentioned preparation method in personal care products is provided.

[0024] Specifically, the powdered carbomer polymer described in this application is prepared by drying after polymerization in a solvent. During the preparation process, in addition to the primary crosslinking that occurs during the polymerization of crosslinking monomers (component (3)) containing at least two olefinic unsaturated groups, the carbomer particles can also undergo secondary crosslinking through the reaction of the epoxy groups of aliphatic polyol glycidyl ether (component (4)) with the carboxyl groups on the surface of the powdered carbomer during drying, forming a double-crosslinked network of powdered carbomer polymer. Component (2) is an olefinic unsaturated monomer that can copolymerize with carboxylic acid-containing monomers. Introducing this structure into the molecular chain segment can effectively enhance the association between the carbomer chain segment and other substances in the system, resulting in a larger yield value for the formed system. In subsequent applications, after neutralization, water absorption, swelling, and extrusion, the hydrogen bonds between the powdered carbomer polymer particles become covalent bonds, which improves the deformation resistance and sliding between the swollen particles, and enhances its suspension in the formulation. Especially when stored at high temperatures above 50°C, the hydrogen bonding forces between particles decrease, particle movement accelerates, and the Carbopol powder with a double cross-linked network exhibits more durable suspension properties.

[0025] It should be noted that powdered carbomer is typically prepared by polymerizing acrylic acid with an optional crosslinking agent in a reaction vessel equipped with a stirrer and solvent using a free radical initiator. This solvent is a good solvent for the monomer but a poor solvent for the resulting polymer. Shortly after the start of the polymerization reaction and during the reaction itself, the nascent polymer particles begin to precipitate from the solvent, gradually flocculating into aggregates as the reaction proceeds. These aggregates continue to form, eventually creating a white slurry of a certain viscosity. After drying at 90-120°C to remove the solvent, a white powder is formed. At this drying temperature, the epoxy groups of the aliphatic polyol glycidyl ether can further react with the carboxyl groups on the surface of the powdered carbomer particles, forming secondary crosslinks between the particles. This degree of crosslinking is weak and does not affect the overall swelling capacity of the powdered carbomer, thus not altering its thickening and rheological effects. However, it improves the overall stability of the powdered carbomer and enhances its suspension properties, especially its suspension after high-temperature heat storage in the formulation.

[0026] In this application, the aliphatic polyol glycidyl ether can be added to the reaction system together with the monomer, or it can be added during the polymerization process, preferably before drying after polymerization.

[0027] In this application, the free radical initiator is conventionally, typically and non-limitingly, included in the art one or more of the following: azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, dodecyl peroxide, di(2-ethylhexyl) peroxide (CAS: 16111-62-9), disec-butyl peroxide (CAS: 19910-65-7), diisopropyl peroxide (CAS: 105-64-6), dicyclohexyl peroxide (CAS: 1561-49-5), di(hexadecyl)dicarbonate peroxide (CAS: 26322-14-5), and di-n-propyl peroxide (CAS: 16066-38-9).

[0028] In this application, the drying temperature is selected from the range of 90-120℃, and the drying time is selected from the range of 2-12 hours. Drying at 120℃ requires a controlled drying time of 2 hours; prolonged high-temperature drying will cause the carbomer powder to fuse and clump, rendering it unusable. Drying at 90℃ requires a controlled drying time of 12 hours to further remove residual monomers and solvents. Drying at temperatures below 90℃ for longer periods is not recommended, firstly because the reaction between epoxy groups and carboxyl groups slows down significantly below 90℃, and secondly because prolonged drying increases production costs.

[0029] In the technical solution of this application, a dispersant may be added or not added before, during, or after the reaction. The dispersant consists of a first segment solubilized by the organic solvent used in the reaction medium and a second segment that is substantially insoluble in the organic solvent but acts as an adjunct to the dispersed polymer particles. The solubilized segment of the dispersant extends sufficiently away from the polymer particles, forming a steric hindrance barrier to prevent the aggregation or cohesion of individual polymer particles, thereby stabilizing the polymer in the dispersion. Preferably, the dispersant is a nonionic emulsifier with an HLB value of 2-6.5, preferably one or more of propylene glycol monostearate (HLB value 3.4), sorbitan stearate (HLB value 4.7), sorbitan tristearate (HLB value 2.1), and diethylene glycol monolaurate (HLB value 6.1). These dispersants are commonly used in the art.

[0030] In this application, the powdered carbomer polymer is used as a suspension rheology modifier in personal care products, typically and non-limitingly, for use as a suspension rheology modifier in bath liquids, skin creams, toothpastes, shampoos, hairsprays, and other cosmetics. It is particularly suitable for suspending high-density, large particles such as physical sunscreens (titanium dioxide, zinc oxide), mineral pigments, abrasive particles (mica flakes, nut shell powder), suspending high concentrations of oil phases, and for applications requiring longer-term suspension stability.

[0031] The technical solution of this application has the following advantages: The powdered carbomer polymer provided in this application comprises the following raw materials: component (1), an olefinically unsaturated carboxylic acid-containing monomer; component (2), an olefinically unsaturated monomer that is different from component (1) but can be copolymerized with it; component (3), a crosslinking monomer containing at least two olefinically unsaturated groups; and component (4), an aliphatic polyol glycidyl ether crosslinking agent containing at least two glycidyl ether groups; wherein, based on the total mass of components (1), (2), (3), and (4), the mass percentage of component (4) is 0.01%-0.5%. The powdered carbomer polymer provided in this application, through the limitation of raw materials, especially the combined use of components (3) and (4), allows the carbomer particles to undergo secondary crosslinking through the reaction of the epoxy groups contained in the aliphatic polyol glycidyl ether (component (4)) with the carboxyl groups on the surface of the powdered carbomer during the polymerization of the crosslinking monomer (component (3)) containing at least two olefinic unsaturated groups, in addition to the primary crosslinking. This is achieved by the secondary crosslinking of the powdered carbomer polymer through the reaction of the epoxy groups contained in the aliphatic polyol glycidyl ether (component (4)) with the carboxyl groups on the surface of the powdered carbomer during the drying process, forming a double-crosslinked network. The use of component (2) can effectively enhance the association between the carbomer segments and other substances in the system, resulting in a larger yield value of the formed system. During subsequent use, after neutralization, water absorption, swelling, and extrusion, the hydrogen bonds between the particles become covalent bonds, improving the deformation resistance and sliding between the swollen particles, and enhancing their suspension properties in the formulation. Especially during high-temperature heat storage above 50°C, the hydrogen bond forces between the particles decrease, the particle movement accelerates, and the double-crosslinked network powdered carbomer exhibits more durable suspension properties.

[0032] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Detailed Implementation

[0033] The following embodiments are provided to better understand this application. However, the following embodiments do not constitute a limitation on the content and scope of protection of this application. Any product that is the same as or similar to this application, derived by anyone under the guidance of this application or by combining the features of this application with other prior art, falls within the scope of protection of this application.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having” and any variations thereof in the text of this application are intended to cover non-exclusive inclusion.

[0035] In the description of the embodiments of this application, the technical terms "first", "second", etc. are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0036] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0037] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers from a to b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed herein, and "0-5" is merely a shortened representation of these numerical combinations. Furthermore, when a parameter is described as an integer ≥ 2, it is equivalent to disclosing that the parameter can be, for example, integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0038] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0039] In the description of the embodiments of this application, the term "at least one" refers to one or more (including two).

[0040] Unless otherwise specified, all steps in this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps S1 and S2, indicating that the method may include steps S1 and S2 performed sequentially, or it may include steps S2 and S1 performed sequentially. For example, the method may also include step S3, indicating that step S3 may be added to the method in any order. For example, the method may include steps S1, S2, and S3, or it may include steps S1, S3, and S2, or it may include steps S3, S1, and S2, etc.

[0041] Unless otherwise specified, all experimental steps or conditions in the examples were performed according to conventional experimental procedures and conditions in the art. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0042] The present application will now be described with reference to specific embodiments. It should be noted that these embodiments are merely descriptive and do not limit the present application in any way.

[0043] The main raw materials and information used in the following embodiments and comparative examples of this application are shown in Table 1 below: Table 1

[0044] The main equipment information used in the following embodiments and comparative examples of this application is shown in Table 2 below: Table 2

[0045] Example 1 This embodiment provides a powdered carbomer polymer, the specific preparation method and operating parameters of which are as follows: 2500 kg of cyclohexane and 2500 kg of ethyl acetate were added to a stainless steel polymerization reactor and mixed thoroughly. Nitrogen gas was then purged for at least 30 minutes to reduce the oxygen content in the system to 1 × 10⁻⁶. -7 Below mg / L; Add 949.5 kg of acrylic acid, 35 kg of lauryl acrylate, and 13 kg of trimethylolpropane diallyl ether to the above polymerization reactor, mix evenly, and continuously purge with nitrogen to replace oxygen. The reaction temperature was raised to 48℃, and 6 kg of di(2-ethylhexyl) peroxide dicarbonate initiator was added to the polymerization reactor to start the polymerization reaction. The reaction was carried out for 6 hours until the reaction was complete. Maintain the reaction temperature at 48℃, add a mixed solution of 125 kg ethyl acetate, 125 kg cyclohexane and 2 kg benzoyl peroxide (to eliminate residual monomethyl ether), and further treat for 2 h to eliminate residual monomethyl ether. After the treatment is completed and cooled to room temperature, add 2.5 kg polyethylene glycol diglycidyl ether (polyethylene glycol has a molecular weight of 200) to obtain a suspension. The obtained suspension was transferred into a dryer, and dried at a temperature of 90°C under negative pressure for 12 hours to obtain carbomer powder.

[0046] Example 2 This embodiment provides a powdered carbomer polymer, the specific preparation method and operating parameters of which are as follows: 1700 kg of cyclohexane and 3400 kg of ethyl acetate were added to a stainless steel polymerization reactor, followed by 2 kg of dehydrated sorbitan tristearate. The mixture was thoroughly mixed, and nitrogen was purged for at least 30 minutes to reduce the oxygen content in the system to 1 × 10⁻⁶. -7 Below mg / L; Add 948 kg of acrylic acid, 40 kg of stearate acrylate, 8 kg of tripentaerythritol triallyl ether, and 4 kg of polyethylene glycol diglycidyl ether (polyethylene glycol has a molecular weight of 400) to the reactor, mix well, and continuously purge with nitrogen to replace oxygen. The reaction temperature was raised to 62℃, and 2.2 kg of dodecyl peroxide was added to start the polymerization reaction. The reaction was carried out for 7 hours until the reaction was complete. Maintain the reaction temperature at 62℃, add a mixed solution of 360 kg ethyl acetate, 180 kg cyclohexane and 2 kg dodecyl peroxide, and further treat for 2 h to eliminate residual monomer. After the treatment is completed, cool to room temperature to obtain a suspension of the fractional carbomer polymer. The obtained suspension was transferred into a dryer, and dried at 100°C under negative pressure for 8 hours to obtain carbomer powder.

[0047] Example 3 This embodiment provides a powdered carbomer polymer, the specific preparation method and operating parameters of which are as follows: 2900 kg of cyclohexane and 1850 kg of ethyl acetate were added to a stainless steel polymerization reactor, followed by 9 kg of diethylene glycol monolaurate. The mixture was thoroughly mixed, and nitrogen was purged for at least 30 minutes to reduce the oxygen content in the system to 1 × 10⁻⁶. -7 Below mg / L; Add 938 kg of acrylic acid, 50 kg of decyl methacrylate, and 11 kg of trimethylolpropane diallyl ether to the reactor, mix well, and continuously purge with nitrogen to replace oxygen. The reaction temperature was raised to 54℃, and 6.8 kg of azobisisobutyronitrile was added to a four-necked flask to start the polymerization reaction. After 4 hours of reaction, 1 kg of polypropylene glycol diglycidyl ether (polypropylene glycol has a molecular weight of 200) was added, and the reaction was continued for 4 hours until the reaction was complete. Maintain the reaction temperature at 54℃, add a mixed solution of 100kg ethyl acetate, 200kg cyclohexane and 2kg azobisisobutyronitrile, and further treat for 2h to eliminate residual monomers. After the treatment is completed, cool to room temperature to obtain a suspension of powdered carbomer polymer. The obtained suspension was transferred into a dryer, and dried at a temperature of 110°C under negative pressure for 6 hours to obtain carbomer powder.

[0048] Example 4 This embodiment provides a powdered carbomer polymer, the specific preparation method and operating parameters of which are as follows: 1880 kg of cyclohexane and 2820 kg of ethyl acetate were added to a stainless steel polymerization reactor, mixed thoroughly, and purged with nitrogen for at least 30 minutes to reduce the oxygen content in the system to 1 × 10⁻⁶. -7 Below mg / L; Add 967 kg of acrylic acid, 30 kg of docosyl methacrylate, 2 kg of pentaerythritol trially propyl ether and 1 kg of pentaerythritol tetraglycidyl ether to the reactor, mix well, and continuously purge with nitrogen to replace oxygen. The reaction temperature was raised to 48℃, and 7 kg of di(2-ethylhexyl) peroxide dicarbonate was added to start the polymerization reaction. The reaction was carried out for 6 hours until the reaction was complete. Maintain the reaction temperature at 48℃, add a mixed solution of 150kg ethyl acetate, 100kg cyclohexane and 2kg di(2-ethylhexyl) peroxide dicarbonate, and further treat for 2h to eliminate residual monocarbonate. After the treatment is completed, cool to room temperature to obtain a suspension of carbomer powder. The obtained suspension was transferred into a dryer, and dried at a temperature of 120°C under negative pressure for 2 hours to obtain carbomer powder.

[0049] Example 5 This embodiment provides a powdered carbomer polymer, which differs from Example 2 in that it uses a different polymerization formulation, as detailed below: 1700 kg of cyclohexane and 3400 kg of ethyl acetate were added to a stainless steel polymerization reactor, followed by 4 kg of dehydrated sorbitan tristearate. The mixture was thoroughly mixed, and nitrogen was purged for at least 30 minutes to reduce the oxygen content in the system to 1 × 10⁻⁶. -7 Below mg / L; Add 969.9 kg of acrylic acid, 10 kg of stearate acrylate, 20 kg of tripentaerythritol triallyl ether, and 0.1 kg of polyethylene glycol diglycidyl ether (polyethylene glycol has a molecular weight of 400) to the reactor, mix well, and continuously purge with nitrogen to replace oxygen. The reaction temperature was raised to 62℃, and 2.2 kg of dodecyl peroxide was added to start the polymerization reaction. The reaction was carried out for 7 hours until the reaction was complete. Maintain the reaction temperature at 62℃, add a mixed solution of 360 kg ethyl acetate, 180 kg cyclohexane and 2 kg dodecyl peroxide, and further treat for 2 h to eliminate residual monomer. After the treatment is completed, cool to room temperature to obtain a suspension of the fractional carbomer polymer. The obtained suspension was transferred into a dryer, and dried at 100°C under negative pressure for 8 hours to obtain carbomer powder.

[0050] Example 6 This embodiment provides a powdered carbomer polymer, which differs from Example 2 in that it uses a different polymerization formulation, as detailed below: 1700 kg of cyclohexane and 3400 kg of ethyl acetate were added to a stainless steel polymerization reactor, followed by 4 kg of dehydrated sorbitan tristearate. The mixture was thoroughly mixed, and nitrogen was purged for at least 30 minutes to reduce the oxygen content in the system to 1 × 10⁻⁶. -7 Below mg / L; Add 894.9 kg of acrylic acid, 100 kg of stearate acrylate, 4 kg of tripentaerythritol triallyl ether, and 5 kg of polyethylene glycol diglycidyl ether (polyethylene glycol has a molecular weight of 400) to the reactor, mix well, and continuously purge with nitrogen to replace oxygen. The reaction temperature was raised to 62℃, and 2.2 kg of dodecyl peroxide was added to start the polymerization reaction. The reaction was carried out for 7 hours until the reaction was complete. Maintain the reaction temperature at 62℃, add a mixed solution of 360 kg ethyl acetate, 180 kg cyclohexane and 2 kg dodecyl peroxide, and further treat for 2 h to eliminate residual monomer. After the treatment is completed, cool to room temperature to obtain a suspension of the fractional carbomer polymer. The obtained suspension was transferred into a dryer, and dried at 100°C under negative pressure for 8 hours to obtain carbomer powder.

[0051] Example 7 This embodiment provides a powdered carbomer polymer, which differs from Example 2 in that it uses a different polymerization formulation, as detailed below: 1700 kg of cyclohexane and 3400 kg of ethyl acetate were added to a stainless steel polymerization reactor, followed by 2 kg of dehydrated sorbitan tristearate. The mixture was thoroughly mixed, and nitrogen was purged for at least 30 minutes to reduce the oxygen content in the system to 1 × 10⁻⁶. -7 Below mg / L; Add 933 kg of acrylic acid, 50 kg of stearate acrylate, 15 kg of tripentaerythritol triallyl ether, and 2 kg of polyethylene glycol diglycidyl ether (polyethylene glycol has a molecular weight of 400) to the reactor, mix well, and continuously purge with nitrogen to replace oxygen. The reaction temperature was raised to 62℃, and 2.2 kg of dodecyl peroxide was added to start the polymerization reaction. The reaction was carried out for 7 hours until the reaction was complete. Maintain the reaction temperature at 62℃, add a mixed solution of 360 kg ethyl acetate, 180 kg cyclohexane and 2 kg dodecyl peroxide, and further treat for 2 h to eliminate residual monomer. After the treatment is completed, cool to room temperature to obtain a suspension of the fractional carbomer polymer. The obtained suspension was transferred into a dryer, and dried at 100°C under negative pressure for 8 hours to obtain carbomer powder.

[0052] Example 8 This embodiment provides a powdered carbomer polymer, which differs from Example 2 in that it uses a different polymerization formulation, as detailed below: 1700 kg of cyclohexane and 3400 kg of ethyl acetate were added to a stainless steel polymerization reactor, followed by 1.5 kg of dehydrated sorbitan tristearate. The mixture was thoroughly mixed, and nitrogen was purged for at least 30 minutes to reduce the oxygen content in the system to 1 × 10⁻⁶. -7 Below mg / L; Add 928.5 kg of acrylic acid, 60 kg of stearate acrylate, 10 kg of tripentaerythritol triallyl ether, and 1.5 kg of polyethylene glycol diglycidyl ether (polyethylene glycol has a molecular weight of 400) to the reactor, mix well, and continuously purge with nitrogen to replace oxygen. The reaction temperature was raised to 62℃, and 2.2 kg of dodecyl peroxide was added to start the polymerization reaction. The reaction was carried out for 7 hours until the reaction was complete. Maintain the reaction temperature at 62℃, add a mixed solution of 360 kg ethyl acetate, 180 kg cyclohexane and 2 kg dodecyl peroxide, and further treat for 2 h to eliminate residual monomer. After the treatment is completed, cool to room temperature to obtain a suspension of the fractional carbomer polymer. The obtained suspension was transferred into a dryer, and dried at 100°C under negative pressure for 8 hours to obtain carbomer powder.

[0053] Example 9 This embodiment provides a powdered carbomer polymer, which differs from Example 2 in that the composition of component (1) is different, specifically consisting of 500 kg of acrylic acid and 448 kg of fumaric acid.

[0054] Example 10 This embodiment provides a powdered carbomer polymer, which differs from Example 2 in that the composition of component (2) is different, specifically 40 kg of isopropyl acrylate.

[0055] Example 11 This embodiment provides a powdered carbomer polymer, which differs from Example 2 in that the solvent composition is different, specifically cyclohexane is replaced with n-heptane and ethyl acetate is replaced with butyl acetate.

[0056] Comparative Example 1 This comparative example provides a powdered carbomer polymer, which differs from Example 1 in that no component (4) is added.

[0057] Comparative Example 2 This comparative example provides a powdered carbomer polymer, which differs from Example 1 in that the amount of the aliphatic polyol glycidyl ether secondary crosslinking agent polyethylene glycol diglycidyl ether (polyethylene glycol has a molecular weight of 200) is adjusted to 10 kg (accounting for 1%), and the amount of acrylic acid is adjusted to 942 kg.

[0058] Comparative Example 3 This comparative example provides a powdered carbomer polymer, which differs from Example 1 in that it uses an equal mass of component (3) instead of component (4).

[0059] Comparative Example 4 This comparative example provides a powdered carbomer polymer, which differs from Example 1 in that an equal mass of component (4) is used instead of component (3).

[0060] Comparative Example 5 This comparative example provides a powdered carbomer polymer, which differs from Example 1 in that an equal mass of component (1) is used instead of component (2).

[0061] Experimental Example The thickening effect, transparency, and suspension stability in this application are tested using the following methods: 1. Thickening effect test method: Add 208.5g of deionized water to a 300ml, 8cm diameter plastic straight-sided bottle, then add 1.4g of the powdered carbomer polymer provided in each example and comparative example, and let it stand for 8 hours to fully absorb water and swell. Place a stirrer in the bottle, start stirring, and slowly add 18% sodium hydroxide aqueous solution dropwise. Stir at 800rpm for 40-60min, adjusting the pH to 7.5±0.2. Place the bottle in a 25℃ water bath and let it stand for 8 hours to stabilize, then test its viscosity at 20rpm.

[0062] 2. Transparency Test Method: Place the stable sample prepared according to the above method into a centrifuge tube. Place the centrifuge tube in a centrifuge, set the speed to 5000 rpm, and the centrifugation time to 10 minutes. After centrifugation, carefully transfer the sample into a cuvette (to prevent the introduction of air bubbles). Then place the cuvette into a spectrophotometer to measure the transparency.

[0063] 3. Suspension test method: The sample preparation method is as follows: 1) Weigh 83.17g of deionized water into a 300ml straight bottle, place it under a mechanical stirrer, place a four-bladed slanted paddle as close to the bottom of the bottle as possible, turn on the mechanical stirrer, adjust the speed to 200rpm, and start stirring; 2) Weigh 0.55g of carbomer polymer powder sample and slowly add it into the straight bottle near the bottle wall. The addition time should be controlled at 50±5s. After the addition is complete, adjust the speed to 800rpm and stir for 30min. 3) After stirring at 800 rpm, adjust the speed to 200 rpm and stir for 15 minutes until the liquid at the bottom is clear; 4) Adjust the rotation speed to 400 rpm, raise the liquid temperature to 85℃, slowly add 7.35g sodium lauryl ether sulfate and 2.8g cocamidopropyl betaine, and mix well; 5) Adjust the temperature to 60℃, slowly add 0.05g of mica to formula A; slowly add 0.05g of titanium dioxide to formula B, and stir until no aggregated particles of mica or titanium dioxide can be observed; slowly add 1.0g of Dow Corning DC184 polydimethylsiloxane alcohol to formula C and stir evenly. 6) Cool the mixture to room temperature, slowly add 0.5g phenoxyethanol and 0.5g sodium citrate, stir for 30 minutes, and mix thoroughly; 7) Adjust the speed to 500 rpm, add 1.2g of sodium chloride powder, stir for 20 minutes, and mix evenly; 8) While maintaining the rotation speed, slowly add 0.2g of sodium hydroxide and 2.68g of deionized water to complete the preparation of the suspension and silicone oil stability test solution.

[0064] 9) Pour the mixtures of formulations A, B, and C into three transparent glass bottles, place them in a 50°C oven, and observe the particle settling and water separation time of formulations A and B, as well as the silicone oil precipitation and stratification time in formulation C.

[0065] The specific test results are shown in the table below: Table 3

[0066] As can be seen from the data in the table above, the powdered carbomer polymer provided in this application, through the coordination of its components and the adjustment of their dosage, improves the deformation resistance and interparticle sliding of the swollen particles after neutralization, water absorption, swelling, and extrusion during subsequent use, thereby enhancing its suspension properties in the formulation. Especially during high-temperature thermal storage above 50°C, the hydrogen bonding forces between particles decrease, particle movement accelerates, and the double-crosslinked network of powdered carbomer exhibits more durable suspension performance.

[0067] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A powdered carbomer polymer, characterized in that, Raw materials include: Component (1) is an olefinic unsaturated carboxylic acid monomer; Component (2) is an olefinic unsaturated monomer that is different from component (1) but can be copolymerized with it; Component (3) contains a crosslinked monomer with at least two olefinic unsaturated groups; Component (4) is an aliphatic polyol glycidyl ether crosslinker containing at least two glycidyl ether groups; Among them, the mass percentage of component (4) is 0.01%-0.5% based on the total mass of components (1), (2), (3), and (4).

2. The powdered carbomer polymer according to claim 1, characterized in that, The component (4) includes at least one of polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,2-cyclohexanediol diglycidyl ether, glycerol triglycidyl ether, and pentaerythritol tetraglycidyl ether. And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of component (4) is 0.1%-0.25%.

3. The powdered carbomer polymer according to claim 1 or 2, characterized in that, The component (1) includes acrylic acid; And / or, the component (1) comprises acrylic acid and a C4-C6 carboxylic acid containing a double bond; Optionally, the C4-C6 carboxylic acids containing double bonds include at least one of maleic acid, itaconic acid, fumaric acid, methacrylic acid, crotonic acid, and aconitic acid.

4. The powdered carbomer polymer according to claim 1 or 2, characterized in that, The component (2) comprises an alkyl (meth)acrylate having the following chemical formula. composition: CH2=CR1-COOR; Wherein, R includes a straight-chain or branched alkyl group having at least 1 to 30 carbon atoms, and R1 is selected from hydrogen or methyl; Optionally, the component (2) includes at least one of the following: decyl acrylate, isodecyl acrylate, lauryl acrylate, stearate acrylate, docosyl acrylate, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, decyl methacrylate, isodecyl methacrylate, lauryl acrylate, stearate methacrylate, docosyl methacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, octyl methacrylate, and 2-ethylhexyl methacrylate. And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of component (2) is 1%-10%, optionally 3%-7%.

5. The powdered carbomer polymer according to claim 1 or 2, characterized in that, The component (3) comprises a polyfunctional acrylate with at least two polymerizable olefinic unsaturated double bonds and / or a polychain alkenyl ether containing at least two polymerizable olefinic unsaturated double bonds; optionally, it comprises one or more of allyl pentaerythritol, allyl sucrose, allyl acrylate, and trimethylolpropane diallyl ether. And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of component (3) is 0.01%-2%, optionally 0.1%-1.5%, and more preferably 0.5%-1%.

6. A method for preparing the powdered carbomer polymer according to any one of claims 1-5, characterized in that, include: Components (1), (2), (3), and (4) were polymerized in a solvent and then dried.

7. The method for preparing powdered carbomer polymer according to claim 6, characterized in that, The polymerization reaction includes the following steps: S1, the components (1), (2), (3), and the first free radical initiator are subjected to a first reaction in a solvent; S2, with the addition of a second free radical initiator, proceeds to the second reaction; The timing of adding component (4) is as follows: adding it together with component (1), adding it during the first or second reaction, adding it after the first or second reaction; optionally, adding it after the second reaction.

8. The method for preparing powdered carbomer polymer according to claim 7, characterized in that, The temperature of the first reaction is 40-70℃, and the reaction time is 3-8 hours; And / or, the temperature of the second reaction is 40-70℃, and the reaction time is 1-3h; And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of the first free radical initiator is 0.05%-2%; And / or, based on the total mass of components (1), (2), (3), and (4), the mass percentage of the second free radical initiator is 0.02%-1%; And / or, the drying temperature is 90-120℃, and the drying time is 2-12 hours.

9. The method for preparing powdered carbomer polymer according to any one of claims 7-8, characterized in that, With the total mass of components (1), (2), (3), and (4) and the solvent being 100%, the amount of solvent used is 83%-92%; And / or, the solvent includes at least one of the following: hydrocarbons containing 6-40 carbon atoms, carbon halogenates containing 6-40 carbon atoms, chlorinated hydrocarbons containing 6-40 carbon atoms, esters containing 6-40 carbon atoms, and ketones containing 6-40 carbon atoms; Optionally, the solvent is a mixture of cyclohexane and ethyl acetate; more preferably, the mass ratio of cyclohexane to ethyl acetate is 1:9-9:

1. And / or, the first free radical initiator and the second free radical initiator independently include at least one of organic peroxide compounds and azo compounds.

10. The use of a powdered carbomer polymer according to any one of claims 1-5 or a powdered carbomer polymer prepared by the preparation method according to any one of claims 6-9 in personal care products.

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