Aqueous antioxidant suspoemulsion and process for preparing same - Patents.com

Abstract

The present disclosure relates to an aqueous antioxidant suspoemulsion comprising at least one solid antioxidant present as particles in a continuous aqueous phase and at least one liquid antioxidant present as droplets in a dispersed oil phase. The present disclosure further relates to a process for preparing the aqueous antioxidant suspoemulsion and to a polymer composition comprising the aqueous antioxidant suspoemulsion.

Description

[Technical field]

[0001] The present disclosure relates to an aqueous antioxidant suspoemulsion, a process for preparing the aqueous antioxidant suspoemulsion, and a polymer composition comprising the aqueous antioxidant suspoemulsion. [Background technology]

[0002] Polymers such as plastics, rubbers, and resins tend to oxidize and deteriorate during their manufacturing and application and service life. Thus, the appearance and physical and mechanical performance of polymeric materials are prone to deterioration. For example, ABS (acrylonitrile butadiene styrene) resin is a terpolymer consisting of acrylonitrile, butadiene, and styrene. ABS resin is widely used in various fields due to its excellent impact resistance, chemical resistance, and processability. However, ABS resin has poor weather resistance (light / heat) due in part to the inclusion of butadiene molecular chains in it. Therefore, ABS resin is easily oxidized when exposed to heat, light, and / or oxygen in the environment, and therefore gradually turns yellow, becomes hard, and becomes brittle.

[0003] In addition, ABS resin is generally produced by emulsion polymerization. In the preparation process, the resulting ABS latex is subjected to coagulation, dehydration and drying treatments. The drying treatment is generally carried out at 110-130°C. Under such high temperature conditions, the ABS powder is more susceptible to oxidation.

[0004] Adding antioxidant is a typical solution to prevent and alleviate the above problems. When the polymer is produced by suspension polymerization / microsuspension polymerization / emulsion polymerization, it is especially desired to have an antioxidant composition in a dispersed form that not only has good antioxidant performance but also is easy to handle.

[0005] In addition, the art is desirous of antioxidant combinations that contain at least two different antioxidants to obtain synergistic effects in terms of oxidation prevention.However, the antioxidant combinations available on the market are mainly limited to two or more solid antioxidants in suspension form, or two or more liquid antioxidants in emulsion form.It is desirous to expand the scope of suitable antioxidant combinations in dispersion form, and in particular to provide combinations of solid antioxidants and liquid antioxidants.

[0006] To achieve this goal, several attempts have been made. For example, CN110627929A disclosed a process for preparing a nano-grade aqueous antioxidant emulsion for stabilizing polymers with solid antioxidants by melt emulsification and homogenization. CN10218072B disclosed a process for preparing an aqueous antioxidant emulsion containing solid and liquid antioxidants by melt emulsification process. During the preparation process of CN110627929A and CN10218072B, the solid antioxidant is first melted at high temperature and then emulsified with an emulsifier. However, the production cost of these methods is high, since the reaction vessel needs to be kept at high temperature (i.e., above the melting point of the solid antioxidant) in the main production step to keep the solid antioxidant in a molten state, and the performance of the antioxidant may be deteriorated by high temperature treatment. Summary of the Invention [Means for solving the problem]

[0007] In view of the above shortcomings, the present disclosure aims to provide a novel antioxidant dispersion prepared by combining an antioxidant emulsion and an antioxidant suspension, which can be easily added subsequently to the suspension / microsuspension / emulsion polymerization of polymers, which is economically viable and imparts thermal stability, as well as good antioxidant and anti-aging performance to the final polymer product.

[0008] In a first aspect, the present disclosure provides an aqueous antioxidant suspoemulsion comprising: (i) a continuous aqueous phase of component (C1), (a) at least one solid antioxidant having a melting point above 20° C.; (b) a first surfactant; and (c) Water in which a solid antioxidant is suspended a continuous aqueous phase comprising; (ii) a dispersed oil phase of component (C2), (d) at least one liquid antioxidant having a melting point below 20° C.; and (e) a second surfactant having a liquid antioxidant dispersed in water; a dispersed oil phase comprising An aqueous antioxidant suspoemulsion is provided in which the solid antioxidant is present in the form of particles having a median particle size D50 of less than 10 μm and the liquid antioxidant is present in the form of droplets having a median particle size D50 of less than 10 μm.

[0009] The aqueous antioxidant suspoemulsion provided in the first aspect of the present disclosure comprises a solid antioxidant present as particles in a continuous aqueous phase and a liquid antioxidant present as droplets in a dispersed oil phase in one formulation, which greatly expands the range of suitable antioxidant blends, in particular the solid antioxidant particles and the liquid antioxidant droplets are independent / separate from each other in the continuous aqueous phase.

[0010] In addition, the aqueous antioxidant suspoemulsion of the present disclosure is thermally stable and also exhibits excellent antioxidant performance for protecting polymeric materials from oxidation caused by high temperatures, etc., thereby extending the life cycle of the products.

[0011] In a second aspect, the present disclosure provides a process for preparing an aqueous antioxidant suspoemulsion comprising: Step 1. Preparing a suspension of solid antioxidant by mixing at least one solid antioxidant having a melting point above 20° C., a first surfactant with water; Step 2. Preparing an oil-in-water emulsion of a second antioxidant by mixing at least one liquid antioxidant having a melting point below 20° C., a second surfactant, and water; Step 3. Preparing an aqueous antioxidant suspoemulsion by adding the oil-in-water emulsion prepared in step 2 to the suspension prepared in step 1 under continuous stirring; homogenizing the solid antioxidants and the liquid antioxidants until the median particle size D50 of the solid antioxidants and the liquid antioxidants is less than 10 μm; The present invention provides a process for preparing an aqueous antioxidant suspoemulsion, comprising:

[0012] Alternatively, the aqueous antioxidant suspoemulsion of the present disclosure comprises: Step 1. Preparing a suspension of solid antioxidant by mixing at least one solid antioxidant having a melting point above 20° C., a first surfactant with water; Step 2. Preparing a self-emulsifying concentrate of a liquid antioxidant by mixing at least one liquid antioxidant having a melting point less than 20° C. with a second surfactant; Step 3. Preparing an aqueous antioxidant suspoemulsion by adding the self-emulsifying concentrate prepared in step 2 to the suspension prepared in step 1 under continuous stirring; homogenizing the solid antioxidants and the liquid antioxidants until the median particle size D50 of the solid antioxidants and the liquid antioxidants is less than 10 μm; It can also be prepared by

[0013] Compared with the prior art, the present process does not require melting of the solid antioxidant. The inventors have found that a stable aqueous antioxidant suspoemulsion can be obtained when the particle size of the solid / liquid antioxidant is reduced to less than 10 μm (possible by homogenization (e.g., by homogenizer)). Therefore, the present process does not require melt (high temperature) treatment of the solid antioxidant, making the process simpler and more cost-effective.

[0014] In addition, the antioxidant performance of the solid antioxidant is better maintained even without high temperature treatment.

[0015] In a third aspect, the present disclosure also provides an aqueous antioxidant suspoemulsion prepared according to the process described in the second aspect of the present disclosure.

[0016] In a fourth aspect, the present disclosure provides the use of an aqueous antioxidant suspoemulsion in the stabilization of a polymeric material.

[0017] In a fifth aspect, the present disclosure provides a polymer composition comprising a polymer or copolymer in an aqueous suspension or emulsion form; and an aqueous antioxidant suspoemulsion according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] In the following description, the present disclosure will be further described with reference to the embodiments, so as to facilitate a full understanding by those skilled in the art. It should be understood that these embodiments are merely provided to better understand the subject matter of the present disclosure, and are not intended to limit the scope of protection, applicability, or embodiments described in the claims. It should be understood that those skilled in the art can omit, replace, or add various technical features to each embodiment based on actual needs without departing from the spirit of the present disclosure. Furthermore, the technical features described in some embodiments can be combined with the technical features described in other embodiments.

[0019] 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 disclosure belongs.

[0020] In this disclosure, the terms "comprise", "comprising" and various variations thereof can be understood as open-ended terms meaning "including but not limited to". In contrast, the term "consisting of" and various variations thereof exclude any component, step or procedure not specifically described. The term "one embodiment" can be understood as "at least one embodiment", and the term "another embodiment" can be understood as "at least one other embodiment". Other terms that may appear but are not mentioned herein should not be interpreted or limited in a manner contrary to the concept on which the embodiments of the present disclosure are based, unless expressly stated.

[0021] Throughout this disclosure, expressions such as "a," "an," "the," and "one or more" are used interchangeably and are intended to include both the plural and the singular, unless only the singular is expressly specified or clearly indicated by the context. When only the singular is intended, the term "a" is generally used. Additionally, the term "or" is generally intended to include the meaning of "and / or" unless the context clearly dictates otherwise. As used interchangeably herein, "preferred," "preferable," and "preferably" refer to embodiments of the present disclosure that may provide certain advantages under certain circumstances. However, other embodiments may also be preferred under the same circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not suitable, and is not intended to exclude other embodiments from the scope of the present disclosure.

[0022] All percentages, parts and ratios are by weight unless otherwise specified, and fractional numerical ranges include all numbers subsumed within that range (e.g. 5 to 10 includes 5, 5.1, 5.2, 5.55, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, ... 10).

[0023] Throughout this disclosure, references to temperature refer to values ​​measured at 101.325 Kpa.

[0024] The term "suspoemulsion" (SE) is a mixture / combination of a suspension containing a solid active ingredient and an emulsion containing a liquid active ingredient. The term "aqueous antioxidant suspoemulsion" refers to a solid antioxidant dispersed as particles in a continuous phase, a liquid antioxidant dispersed as oil droplets in a continuous phase, and water used as a continuous phase carrying both the solid antioxidant and the liquid antioxidant. Specifically, the oil droplets containing the liquid antioxidant and the particles of the solid antioxidant are uniformly dispersed in the aqueous continuous phase. In particular, the solid antioxidant particles and the liquid antioxidant droplets are independent / separate from each other in the continuous aqueous phase. The aqueous antioxidant suspoemulsion of the present disclosure can protect polymeric products from oxidation caused by ultraviolet light, high temperature, etc.

[0025] The term "dispersed oil phase" refers to the phase that contains the liquid organic component(s), i.e., at least one liquid antioxidant. The liquid antioxidant(s) are immiscible / non-blendable with water.

[0026] The term "particle size" refers to the diameter of a particle formed by a solid component or the diameter of an oil droplet formed by a liquid component dispersed in a continuous phase. Typical particle / droplet size parameters include D10, D50, D90. The term "median particle size" refers to the D50 value at which 50% by volume of the particles / droplets have a diameter equal to or less than the D50 value. Particle / droplet size can be measured by conventional particle size analyzers commonly used in the art.

[0027] As used herein, the term "polymer" or "polymers" includes both homopolymer(s), i.e., polymers prepared from a single reactive compound, and copolymers, i.e., polymers prepared by the reaction of at least two polymer-forming reactive monomeric compounds.

[0028] I. Water-Based Antioxidant Suspoemulsions In view of the existing problems in preventing oxidation of polymers, in a first aspect, the present disclosure provides a method for preventing oxidation of polymers comprising: (i) a continuous aqueous phase of component (C1), (a) at least one solid antioxidant having a melting point above 20° C.; (b) a first surfactant; and (c) Water in which a solid antioxidant is suspended a continuous aqueous phase comprising; (ii) a dispersed oil phase of component (C2), (d) at least one liquid antioxidant having a melting point below 20° C.; and (e) a second surfactant in which the liquid antioxidant is dispersed in water; a dispersed oil phase comprising An aqueous antioxidant suspoemulsion is provided in which the solid antioxidant is present in the form of particles having a median particle size D50 of less than 10 μm and the liquid antioxidant is present in the form of droplets having a median particle size D50 of less than 10 μm.

[0029] The aqueous antioxidant suspoemulsion of the present disclosure contains in one formulation a solid antioxidant present as particles in a continuous aqueous phase and a liquid antioxidant present as droplets in a dispersed oil phase.Thus, the present disclosure provides a new system, an antioxidant combination in aqueous suspoemulsion form, suitable for stabilizing polymeric materials synthesized by suspension / microsuspension / emulsion polymerization, greatly expanding the range of suitable antioxidant blends.

[0030] Additionally, the aqueous antioxidant suspoemulsions of the present invention have no upper limit on the melting point of a suitable solid antioxidant, so long as the melting point of the solid antioxidant is greater than 20°C and is thereby solid at 20°C.

[0031] On the other hand, the aqueous antioxidant suspoemulsion of the present disclosure is thermally stable since the median particle size of the solid and liquid antioxidants is less than 10 μm. No observable creaming or precipitation occurs during storage.

[0032] The aqueous antioxidant suspoemulsions of the present disclosure also exhibit excellent antioxidant performance for protecting polymeric materials from oxidation caused by high temperatures, oxygen, etc., thereby extending the product life cycle. In some embodiments, the aqueous antioxidant suspoemulsions of the present disclosure also exhibit strong synergistic effects in terms of thermal stabilization and oxidation protection, as indicated by significantly increased OIT peak times.

[0033] Solid antioxidant(s) The type of suitable solid antioxidant is not particularly limited in the present disclosure, as long as it has a melting point above 20° C. Examples include, but are not limited to, solid forms of hindered phenols, thioesters, thioethers, amines, hydroxylamines, lactones, lactone-phosphites, or lactone-phosphates. Those skilled in the art can select one or more suitable solid antioxidant(s) for each specific application.

[0034] Solid antioxidants suitable for the present disclosure have a melting point above 20° C., e.g., above 25° C., above 30° C., above 35° C., above 40° C., above 50° C., above 60° C., above 70° C., above 80° C., above 90° C., or above 100° C., such that the solid antioxidant is present in solid form at 20° C., which is a typical room temperature for preparing antioxidant compositions. Antioxidants having a melting point above 25° C., especially above 30° C., are more preferred.

[0035] Examples of suitable solid antioxidant(s) include octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (e.g., Irganox® 1076), 3,3′-thiodipropionic acid dioctadecyl ester (e.g., Irganox® PS 802, etc.), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (e.g., Irganox® 1010), 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazin-2-ylamino)phenol (e.g., Irganox® 565), 3,3',3',5,5',5'-hexa-tert-butyl-a,a',a'-(mesitylene-2,4,6-triyl)tri-p-cresol (e.g., Irganox® 1330), reaction products of phenol, 4-methyl-, with dicyclopentadiene and isobutylene (e.g., Wingstay® L), ethylene bis(oxyethylene) bis[3-(5-tert-butyl-4-hydroxyphenyl)propionate] (e.g., Irganox® 1010), 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazin-2-ylamino)phenol (e.g., Irganox® 565), 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)trione (e.g., Irganox® 3114), thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (e.g., Irganox® 1035), N,N'-hexane-1,6-diylbis(3-3,5-di-tert-butyl-4-hydroxyphenylpropionamide) (e.g., Irganox® 1098), N,N'-bis(3,5-di-tert-butyl-4-hydroxyl-phenylpropionyl)hydrazine (e.g., Irganox® MD 1024), 1,3,5-tris[(4-tert-butyl-3-hydroxy-2,6-dimethylphenyl)methyl]-1,3,5-triazinane-2,4,6-trione (e.g., Cyanox® 1790), 2,2'-methylenebis(4-methyl-6-tert-butylphenol);Hexamethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (e.g., Irganox® 259), butylated hydroxytoluene (abbreviated as BHT), 2-(1,1-dimethylethyl)-6-[[3-(1,1-dimethylethyl)-2-hydroxy-5-methylphenylmethyl-4-methylphenylacrylate (e.g., Irganox® 305 2), 2,2-bis[[3-(dodecylthio)-1-oxopropoxy]methyl]propane-1,3-diylbis[3-(dodecylthio)propionate] (e.g., Seenox® 412s), 2,4-bis(dodecylthiomethyl)-6-methylphenol (e.g., Irganox® 1726), didodecyl-3,3′-thiodipropionate (e.g., Irganox® PS 800, etc.), and combinations thereof;

[0036] Examples of suitable lactones in solid form include, but are not limited to, those described in WO 8001566, U.S. Pat. No. 5,516,920, U.S. Pat. No. 4,325,863, U.S. Pat. No. 4,488,117, U.S. Pat. No. 8,653,284, U.S. Pat. Publication No. 20210171747, and U.S. Pat. No. 8,840,810, which are incorporated herein in their entireties. Examples of lactone-phosphites, lactone-phosphates, or analogs thereof include, but are not limited to, those described in WO 15121445 and WO 17025431, which are incorporated herein in their entireties.

[0037] In some preferred embodiments, the solid antioxidant is 3,3'-thiodipropionic acid dioctadecyl ester (e.g., Irganox® PS 802), 3,3',3',5,5',5'-hexa-tert-butyl-a,a',a'-(mesitylene-2,4,6-triyl)tri-p-cresol (e.g., Irganox® 1330), 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazin-2-ylamino)phenol (e.g., Irganox® 565), reaction products of phenol, 4-methyl-, dicyclopentadiene and isobutylene (e.g., Wingstay® L), ethylene bis(oxyethylene) bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate], ethylene ... bis[(4-tert-butyl-3-hydroxy-2,6-dimethylphenyl)methyl]-1,3,5-triazinane-2,4,6-trione (e.g., Cyanox® 1790), 2,2-bis[[3-(dodecylthio)-1-oxopropoxy]methyl]propane-1,3-diylbis[3-(dodecylthio)propionate] (e.g., Seenox® 412s), 2,4-bis(dodecylthiomethyl)-6-methylphenol (e.g., Irganox® 1726), and combinations thereof. These solid antioxidants have better thermal stability.

[0038] The solid antioxidant is present as particles with a median particle size D50 of less than 10 μm, preferably less than 5 μm, more preferably less than 2 μm. The smaller the particle size of the solid antioxidant particles, the more stable the aqueous antioxidant suspoemulsion. If the median particle size D50 is greater than 10 μm, there is a high risk of coagulation. Methods for achieving the above median particle size D50 are well known in the art. A detailed description of the applicable methods and equipment is provided in the second aspect below (II. Process for preparing an aqueous antioxidant suspoemulsion).

[0039] Liquid antioxidant(s) The type of suitable liquid antioxidant is not particularly limited in the present disclosure, as long as it has a melting point below 20° C. Examples include, but are not limited to, liquid forms of hindered phenols, thioesters, thioethers, amines, hydroxylamines, or lactones. Those skilled in the art can select one or more suitable liquid antioxidant(s) for each particular application.

[0040] Liquid antioxidants suitable for the present disclosure have a melting point below 20° C., such as below 15° C., below 10° C., or below 5° C., such that the liquid antioxidant is in liquid form at 20° C., which is a typical room temperature for preparing antioxidant compositions. Antioxidants having a melting point below 15° C., especially below 10° C., are more preferred.

[0041] Examples of suitable liquid antioxidants include 4,6-bis(octylthiomethyl)-o-cresol (e.g. Irganox® 1520 L); 2,4-dimethyl-6-(1-methylpentadecyl)phenol (cas: 134701-20-5, e.g. Irganox® 145); benzenepropanoic acid, 3,5-bis(1,1-dimethyl-ethyl)-4-hydroxy-C7-C9 branched alkyl ester (e.g. Irganox® 1135); benzenamine, N-phenyl-, reaction product with 2,4,4-trimethylpentene (e.g. Irganox® 1135). 5057); ditridecyl 3,3'-thiodipropionate (e.g., Songnox® DTDTDP); benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, C13-15 branched and straight chain alkyl esters (e.g., Anox® 1315); bis[2-methyl-4-{3-n-alkyl(C12 or C14)thiopropionyloxy}-5-tert-butylphenyl]sulfide (e.g., ADK stab® AO 23); thiobis-[2-tert-butyl-5-methyl-4,1-phenylene]bis[3-(dodecylthio)propionate] (e.g., ADK stab® AO 26); and combinations thereof.

[0042] Examples of suitable lactones in liquid form include, but are not limited to, those described in WO 8001566, U.S. Pat. No. 5,516,920, U.S. Pat. No. 4,325,863, U.S. Pat. No. 4,488,117, U.S. Pat. No. 8,653,284, U.S. Patent Publication No. 20210171747, and U.S. Pat. No. 8,840,810, the entireties of which are incorporated herein.

[0043] In some preferred embodiments, the liquid antioxidant is selected from the group consisting of 4,6-bis(octylthiomethyl)-o-cresol (e.g., Irganox® 1520 L); benzenepropanoic acid, 3,5-bis(1,1-dimethyl-ethyl)-4-hydroxy-C7-C9 branched alkyl ester; benzeneamine, N-phenyl-, reaction product with 2,4,4-trimethylpentene (e.g., Irganox® 5057); ditridecyl 3,3′-thiodipropionate (e.g., Songnox® DTDTDP), benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, C13-15 branched and linear alkyl ester (e.g., Anox® 1315), and combinations thereof. These liquid antioxidants have better thermal stability and are more effective in terms of oxidation prevention.

[0044] In some preferred embodiments, the liquid antioxidant is present as droplets with a median particle size D50 of less than 10 μm, preferably less than 5 μm, more preferably less than 2 μm. The smaller the droplet size of the liquid antioxidant droplets, the more stable the aqueous antioxidant suspoemulsion is. Methods for achieving the above median particle size D50 are well known in the art. A detailed description of applicable methods and equipment is provided in the second aspect below.

[0045] In some preferred embodiments, the solid antioxidant, together with the liquid antioxidant, is present in an amount of at least 20 wt%, preferably at least 30 wt%, based on the total weight of the aqueous antioxidant suspoemulsion. The solid antioxidant and the liquid antioxidant can be present in the formulation in any weight ratio. For example, the weight ratio of the solid antioxidant to the liquid antioxidant ranges from 1:50 to 50:1, 1:40 to 40:1, 1:30 to 30:1, 1:20 to 20:1, 1:10 to 10:1, and 1:5 to 5:1.

[0046] In some preferred embodiments, in the aqueous antioxidant suspoemulsion of the present invention, the solid antioxidant is a half-hindered phenol and the liquid antioxidant is a thiosynergist. Compared to fully hindered phenols, half-hindered phenols are more preferred since they exhibit less steric hindrance and are more effective in terms of antioxidant performance. Examples of half-hindered phenols are already known in the art. For example, Irganox® 245 (chemical name: ethylene bis(oxyethylene) bis-(3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate)) from BASF, Sumilizer® GP (2-tert-butyl-6-methyl-4-[3-(2,4,8,10-tetratert-butylbenzo[d][1,3,2]benzodioxaphosphepin-6-yl)oxypropyl]phenol; cas: 203255-81-6) from Sumitomo, Sumilizer® GA 80 (3,9-bis[2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane, cas: 90498-90-1), Sumilizer® GS (2-Propenoic acid, 2-[1-[3,5-bis(1,1-dimethylpropyl)-2-hydroxyphenyl]ethyl]-4,6-bis(1,1-dimethylpropyl)phenyl ester, cas: 1239 68-25-2), and Sumilizer® GM (2-tert-butyl-6-(3-tert-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate, cas: 61167-58-6), and Cyanox® 1790 (1,3,5-tris(4-(tert-butyl)-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazinane-2,4,6-trione, cas: 40601-76-1) from Solvay. Thiosynergists also include thioethers and thioesters, which are known in the art.

[0047] Surfactant(s) The surfactant(s) become part of the suspoemulsion to prevent creaming, coagulation or precipitation, or other phase separation during storage.

[0048] In the present disclosure, the type of suitable surfactant is not particularly limited.The surfactant of the present disclosure can be a nonionic surfactant or an ionic surfactant.Ionic surfactants include anionic surfactants, cationic surfactants, and combinations thereof.Those skilled in the art can select one or more suitable surfactants for each specific application.

[0049] In the present disclosure, preference is given to non-ionic surfactants, anionic surfactants, or combinations thereof.

[0050] Examples of suitable surfactants include alcohol ethoxylates, amine ethoxylates, phenol ethoxylates, alkyl polyglucosides, fatty alcohol alkoxylates, fatty alcohol polyglycol ethers, amine alkoxylates, Guerbet alcohol alkoxylates, amine polyols, polyethylene glycols, methyl polyethylene glycols, alkyl polyethylene glycol copolymers, alkyl polypropylene glycols, polyethylene oxide homopolymers / copolymers, polypropylene oxide homopolymers / copolymers, multifunctional polyalkylene glycols, fatty alcohol sulfates, fatty alcohol ether sulfates, linear alkyl benzene sulfonates, oleic acid sulfonates, stearic acid sulfonates, oleates, stearates.

[0051] These surfactants are commercially available or can be prepared according to known methods.

[0052] In some preferred embodiments, examples of suitable surfactants include methacrylic acid-methyl methacrylate-polyethylene glycol graft copolymers, tristyrylphenol ethoxylates, sulfated or phosphated tristyrylphenol ethoxylates and their salts, propylene oxide-ethylene oxide block copolymers, fully / partially saponified polyvinyl alcohols, alcohol ethoxylates, fatty alcohol sulfates, fatty alcohol ether sulfates, linear alkylbenzene sulfonates, oleic acid sulfonates, oleates, and stearates.

[0053] In some preferred embodiments, the first surfactant and the second surfactant are the same surfactant. Using the same surfactant in both the suspension and emulsion provides ease of operation and a more stable aqueous antioxidant suspoemulsion.

[0054] The amount of surfactant is not particularly limited. For example, in some embodiments, the first surfactant is present in an amount of 1 wt% to 10 wt% based on the total weight of the aqueous antioxidant suspoemulsion together with the second surfactant. When the amount of the first surfactant is 1 wt% or more based on the total weight of the aqueous antioxidant suspoemulsion together with the second surfactant, the aqueous antioxidant suspoemulsion has better stability. Preferably, the first surfactant is present in an amount of 1 wt% to 10 wt%, preferably 3 wt% to 8 wt%, based on the total weight of the aqueous antioxidant suspoemulsion together with the second surfactant.

[0055] In addition to the above-mentioned components, the aqueous antioxidant suspoemulsion of the present disclosure may further comprise one or more additives commonly used in the art. Examples of suitable additives include thickeners, antifreeze agents, antifoam agents, rheology control agents, preservatives, and colorants.

[0056] Examples of thickeners, antifreeze agents, defoamers, rheology modifiers, emulsifiers, dispersants, preservatives, colorants, and inert fillers suitable for the present disclosure are those commonly used in the art. Those skilled in the art can select the appropriate additives for each specific application.

[0057] In some embodiments, the aqueous antioxidant suspoemulsion of the present disclosure may further comprise a light stabilizer, for example, UV absorber (dimethylketone benzene type, oxanilide type, benzotriazole type, triazine type, etc.) and hindered amine light stabilizer (HALS).By adding the light stabilizer, the aqueous antioxidant suspoemulsion of the present disclosure can further protect the polymer from photoaging.

[0058] In the aqueous antioxidant suspoemulsion of the present invention, the continuous phase is water and no organic solvent is used. Therefore, the aqueous antioxidant suspoemulsion of the present invention does not contain organic solvent, which on the one hand makes it economically viable, but on the other hand avoids the wastewater problem caused by the use of organic solvent.

[0059] II. Process for Preparing Aqueous Antioxidant Suspoemulsions In a second aspect, the present disclosure provides a process for preparing an aqueous antioxidant suspoemulsion.

[0060] The aqueous antioxidant suspoemulsion according to the present disclosure can be prepared by the following method. For example, the aqueous antioxidant suspoemulsion can be prepared by: Step 1. Preparing a suspension of solid antioxidant by mixing at least one solid antioxidant having a melting point above 20° C., a first surfactant with water; Step 2. Preparing an oil-in-water emulsion of a second antioxidant by mixing at least one liquid antioxidant having a melting point below 20° C., a second surfactant, and water; Step 3. Preparing an aqueous antioxidant suspoemulsion by adding the oil-in-water emulsion prepared in step 2 to the suspension prepared in step 1 under continuous stirring; The solid and liquid antioxidants can be prepared according to the method described above by homogenizing the solid and liquid antioxidants until the median particle size D50 of the solid and liquid antioxidants is less than 10 μm, preferably less than 5 μm, more preferably less than 2 μm.

[0061] In some other alternative embodiments, the aqueous antioxidant suspoemulsion comprises: Step 1. Preparing a suspension of solid antioxidant by mixing at least one solid antioxidant having a melting point above 20° C., a first surfactant with water; Step 2. Preparing a self-emulsifying concentrate of a liquid antioxidant by mixing at least one liquid antioxidant having a melting point less than 20° C. with a second surfactant; Step 3. Preparing an aqueous antioxidant suspoemulsion by adding the self-emulsifying concentrate prepared in step 2 to the suspension prepared in step 1 under continuous stirring; The solid and liquid antioxidants are prepared according to homogenization until the median particle size D50 of the solid and liquid antioxidants is less than 10 μm, preferably less than 5 μm, more preferably less than 2 μm.

[0062] In some preferred embodiments, homogenization of the solid antioxidant and the liquid antioxidant in the above process can be carried out by a bead mill and / or under high shear.

[0063] In some preferred embodiments, the solid antioxidant is homogenized by grinding in step 1 and / or the liquid antioxidant self-emulsifying concentrate / liquid antioxidant oil-in-water emulsion is homogenized under high shear in step 2.

[0064] According to the present process, a new antioxidant dispersion, i.e., an aqueous antioxidant suspoemulsion prepared from solid and liquid antioxidants, is provided, which is suitable for stabilizing polymeric materials synthesized by suspension / microsuspension / emulsion polymerization, and greatly expands the range of suitable antioxidant blends.

[0065] Furthermore, as mentioned in the background section, in order to prepare an aqueous form of antioxidant using a solid antioxidant and a liquid antioxidant, according to the prior art, the solid antioxidant must first be melted, and most of the preparation steps must be carried out at high temperatures (i.e., above the melting point of the solid antioxidant). In contrast, according to the present process, there is no need to melt the solid antioxidant. The inventors have now found that a stable aqueous antioxidant suspoemulsion can be obtained when the particle size of the solid / liquid antioxidant is reduced to less than 10 μm (possible by homogenization (e.g., by a homogenizer)). Thus, since the present process does not require melt (high temperature) treatment of the solid antioxidant, the present process is simpler and more cost-effective. In addition, the antioxidant performance of the solid antioxidant is better preserved even without high temperature treatment.

[0066] According to the present disclosure, the suspension / self-emulsifying concentrate / oil-in-water emulsion / aqueous antioxidant suspoemulsion can be homogenized by conventional mixing methods, such as known methods for preparing emulsions in the prior art. Mixing and stirring can be performed by conventional dispersion equipment, such as vortex mixers, homogenizers, conventional stirrers with paddle blades, etc. Homogenization of solid antioxidants and liquid antioxidants is performed using equipment such as homogenizers (e.g., bead / ball mills, blades, rotor-stator dispersion homogenizers, etc.) to obtain the desired median particle size D50 of the antioxidants.

[0067] In some preferred embodiments, the solid antioxidant is homogenized by grinding in step 1 until the median particle size D50 of the solid antioxidant is less than 10 μm, preferably less than 5 μm, more preferably less than 2 μm. As mentioned above, most of the processes for preparing aqueous antioxidant suspoemulsions using solid and liquid antioxidants according to the prior art are carried out at a temperature higher than the melting point of the solid antioxidant. Therefore, the melting point of the suitable solid antioxidant should not be higher than 95°C, since the maximum operating temperature of a typical homogenizer can only be set at about 95°C. By homogenizing the solid antioxidant by grinding (e.g., bead / ball mill) according to the present disclosure, it is not necessary to treat the solid antioxidant at high temperatures. The desired median particle size D50 of the present disclosure can be achieved by grinding. Therefore, the suitable solid antioxidant of the present disclosure is not dependent on the melting point, and the present disclosure has no restriction on the upper melting point of the solid antioxidant, which further expands the range of suitable solid antioxidants compared to the current state of the art.

[0068] In some preferred embodiments, the liquid antioxidant is homogenized under high shear in step 2 (e.g., by a blade-type homogenizer) until the median particle size D50 of the liquid antioxidant is less than 10 μm, preferably less than 5 μm, and more preferably less than 2 μm.

[0069] Examples of solid antioxidants, liquid antioxidants and surfactants suitable for this process are the same as those described in the first aspect of this disclosure (I. Aqueous antioxidant suspoemulsions).

[0070] In some embodiments, the process further comprises adding at least one additive selected from the group consisting of thickeners, antifreeze agents, antifoaming agents, rheology modifiers, preservatives, colorants, and inert fillers.The examples of additives suitable for the process are the same as those described in the first embodiment.In addition, these additives can be added at any step in the process for preparing the aqueous antioxidant suspoemulsion.

[0071] III. Aqueous Antioxidant Suspoemulsions Made in Accordance with the Present Disclosure In a third aspect, the present disclosure provides an aqueous antioxidant suspoemulsion produced according to the process described in the second aspect of the present disclosure (II. Process for preparing an aqueous antioxidant suspoemulsion).

[0072] The advantages of the aqueous antioxidant suspoemulsion prepared according to the process described in the second embodiment are set out above.

[0073] IV. Use of Aqueous Antioxidant Suspoemulsions In view of the advantages of the above aqueous antioxidant suspoemulsions, in a fourth aspect, the present disclosure provides the use of the above aqueous antioxidant suspoemulsions in the stabilization of polymeric materials such as materials like rubbers, plastics, resins, etc. The aqueous antioxidant suspoemulsions of the present invention protect substrates from heat / oxygen / light degradation of the polymers during manufacture, processing and end use.

[0074] In particular, the aqueous antioxidant suspoemulsions of the present disclosure are useful in suspension polymerization processes, emulsion polymerization processes or microsuspension polymerization processes.

[0075] V. Polymer Composition As discussed above, the aqueous antioxidant suspoemulsions of the present disclosure can be used in suspension, emulsion, or microsuspension polymerization processes to stabilize polymeric materials such as rubbers, plastics, resins, and the like.

[0076] Thus, in a fifth aspect, the present disclosure provides a method for producing a method for treating a cancer cell comprising: with a polymer in aqueous suspension or emulsion form; An aqueous antioxidant suspoemulsion according to the present disclosure or prepared according to the process of the present disclosure; The present invention provides a polymer composition comprising:

[0077] As used herein, the term "polymer" includes both homopolymer(s) and copolymer(s). The polymers can be prepared by conventional methods such as suspension polymerization, emulsion polymerization, or microsuspension polymerization. The aqueous antioxidant suspoemulsions are particularly suitable for stabilizing polymer latexes, such as ABS latexes. The term "polymer latex" refers to a stable dispersion of polymeric particles in an aqueous medium.

[0078] Examples of applicable polymers include rubber, plastics, and resins, such as polyvinyl chloride (PVC), acrylonitrile butadiene styrene (ABS), and methyl methacrylate butadiene styrene (MBS).

[0079] The blend ratio of the aqueous antioxidant suspoemulsion and the polymer is not particularly limited and can be appropriately selected from a wide range.

[0080] The polymer composition may contain other additives such as thickeners, antifreeze agents, antifoam agents, rheology modifiers, preservatives, colorants, inert fillers, etc. These additives may be added during the preparation of the aqueous antioxidant suspoemulsion and / or during the polymerization of the polymer.

[0081] The aqueous antioxidant suspoemulsion can be easily added or dosed to a polymerization system during polymerization or polymer formulation by conventional methods, such as by pressure. The aqueous antioxidant suspoemulsion of the present disclosure can be uniformly dispersed in the reaction mixture, so that the resulting polymer has excellent stability from preparation to end use.

[0082] The present disclosure is further illustrated by the following examples. EXAMPLES

[0083] [Table 1]

[0084] [Table 2]

[0085] Test Method The particle size of solid antioxidants and droplet size of liquid antioxidants in the aqueous antioxidant suspoemulsions are measured with a Malvern Mastersizer 2000 spectrometer and reported as the median particle size in microns (D50) by diluting a 1.0 ml sample in 40 ml of deionized water.

[0086] The solids content of the aqueous antioxidant suspoemulsion was determined by the following procedure.

[0087] Dry the crystallizing dish in a preheated drying oven at 105 °C for 1 h, then cool in a desiccator for approximately 30 min. Record the weight of the dish as W1. Accurately weigh the sample (approximately 3 g) into a dry crystallizing dish (recorded as W2) and dry at 105 °C for at least 2 h (until constant weight, recorded as W3).

[0088] The solids content is calculated from the following formula: SC = (W3-W1) / W2 x 100 The pH is measured at room temperature using a Metrohm 744 PH Meter.

[0089] Inventive Examples for Preparing Aqueous Antioxidant Suspoemulsions An aqueous antioxidant suspoemulsion according to the present disclosure is prepared according to the following procedure. Step 1. Prepare an aqueous suspension of solid antioxidant: At room temperature (about 20° C.), 200 g of a solid antioxidant as shown in the table below, 20 g of polyvinyl alcohol (PVA), 279 g of deionized water, and 1.0 g of Rhodorsil antifoam agent 416 are mixed and stirred with an ultra turrax.

[0090] The resulting aqueous suspension is milled in a horizontally-disposed agitated bead mill (Dyno-Mill model) until the solid antioxidant D50 particle size is reached as shown in the table below.

[0091] [Table 3]

[0092] Step 2. Preparation of oil-in-water emulsion At room temperature (approximately 20°C), dissolve 4 g of PVA in 46 g of ionized water by stirring, dissolve 50 g of a liquid antioxidant shown in the table below in the water containing the dissolved PVA, and stir the mixture at 10,000 rpm for 3 to 5 minutes using a homogenizer (T18, IKA) to obtain the median particle size D50 of the liquid antioxidant shown in the table below.

[0093] [Table 4]

[0094] Step 3. Preparation of aqueous antioxidant suspoemulsion At room temperature, the oil-in-water emulsion prepared according to step 2 is added to the aqueous suspension prepared according to step 1, and the mixture is stirred with a stirrer at 300 rpm for 5 minutes to make it homogenous.

[0095] [Table 5]

[0096] Alternatively, the aqueous antioxidant suspoemulsion of the present disclosure can be prepared according to the following steps. Step 1. An aqueous suspension of solid antioxidant is prepared in the same manner as described in Step 1 of Invention Example I above. Step 2. Preparation of a self-emulsifying concentrate 4 g of PVA is dissolved in 46 g of liquid antioxidant as shown in the table below under continuous stirring (500 rpm) until a homogenous solution is obtained.

[0097] [Table 6]

[0098] Step 3. Preparation of aqueous antioxidant suspoemulsion At room temperature, the self-emulsifying emulsion prepared according to step 2 is added to the aqueous suspension prepared according to step 1, and the mixture is stirred at 1000 rpm for 5 minutes with a stirrer to make it homogenous.

[0099] [Table 7]

[0100] Stability testing Physical stability tests were conducted on samples of 7B, 1B, 3B, 1C and 7D prepared according to the above invention examples for 14 days at 50° C. to predict storage stability. A formulation is considered stable if its median particle size (D50) changes by less than 10% and no creaming or sedimentation is observed.

[0101] [Table 8]

[0102] From the results in the above table, it can be seen that all of these inventive samples have a D50 of less than 2 μm after storage at 50° C. for 14 days, and the change in D50 is less than 10%. Also, no creaming or precipitation was observed. The aqueous antioxidant suspoemulsions of the present disclosure provide excellent stability. In addition, the pH change of these samples is less than 25%, which is excellent in maintaining the antioxidant performance of the samples, since pH change affects the antioxidant performance.

[0103] ABS OIT Test Material: ABS latex The ABS latex has a solids content of 46% and a particle size distribution (PSD): D50 of 0.3 μm.

[0104] Stabilization and solidification of ABS: 218 g of ABS latex is mixed with 0.94 g of an aqueous antioxidant suspoemulsion prepared according to the invention example. Then, 1.55 g of sulfuric acid (c: 98%) is mixed with 171 g of deionized water at 65°C.

[0105] The stabilized ABS latex is added to a dilute solution of sulfuric acid under continuous stirring at a temperature of about 65° C. to induce coagulation of the ABS substrate, after which the temperature is increased to 93° C. and maintained at this temperature for an additional 3 minutes.

[0106] The slurry is then cooled to room temperature. The slurry is filtered and washed three times with deionized water. The filtrate is dried at 60°C for 20 hours to obtain the dried and stabilized ABS.

[0107] OIT measurement The Oxidation Induction Peak Time (OIT Peak Time) measures the level of heat stabilization of the tested material.

[0108] The OIT peak time of the ABS sample is measured as follows: the solidified and dried stabilized ABS sample is placed in a differential scanning calorimeter (DSC) device and the sample is heated to 198°C under nitrogen atmosphere. Once 198°C is reached, the sample is kept isothermal for 5 minutes and the gas is changed from nitrogen to oxygen. The flow rate of oxygen is maintained at 50 ml / min.

[0109] Under these conditions, the antioxidants are consumed over time. At some point, the ABS sample begins to decompose or oxidize, thereby releasing more heat (an exothermic reaction). The time from the time oxygen is introduced to when this exothermic reaction reaches its peak is reported as the OIT peak time. The longer the OIT peak time, the more thermally stable the ABS is.

[0110] [Table 9]

[0111] [Table 10]

[0112] Compared with the comparative examples (single suspension or emulsion antioxidants), the OIT peak times of most ABS latexes treated with the aqueous antioxidant suspoemulsions of the present disclosure are significantly improved. Thus, the heat stabilization effect of these aqueous antioxidants is superior to that of single suspension or emulsion systems. The aqueous antioxidant suspoemulsions of the present disclosure show strong synergistic effects in terms of heat stabilization, as shown by the significantly increased OIT peak times. Specifically, inventive examples 1B, 1C, 2B, 3B, 4B, 5B, 7D, 7B, 1E and 7F show absolute synergistic effects, as their OIT peak times are longer than those of the single suspension or emulsion systems, respectively.

[0113] In Inventive Example 6A, WSL was combined with DTDTDP (55:45 ratio) to prepare an aqueous antioxidant suspoemulsion. Inventive Example 6A exhibits a much longer OIT peak time (53 min) than the mathematically predicted 32.4 min (54 min (Comparative Example 6)). * 55%+6 minutes (Comparative Example A) * 45% = 32.4 min), thus demonstrating a relative synergistic effect.

[0114] Furthermore, as shown in the above table, inventive example 6A has a good OIT peak time, yet the WSL amount is reduced by half, which is particularly advantageous from a health standpoint.

[0115] Although the embodiments and examples of the present disclosure have been described above, those skilled in the art should understand that they are merely for illustrative purposes and are not intended to limit the scope of protection of the present disclosure. The scope of protection of the present disclosure is defined by the appended claims. Those skilled in the art can make various modifications, equivalent substitutions, or improvements to these embodiments without departing from the scope and spirit of the present disclosure, but these modifications, equivalent substitutions, or improvements fall within the scope of protection of the present disclosure.

Claims

1. A water-based antioxidant suspension emulsion, wherein the water-based antioxidant suspension emulsion is (i) A continuous aqueous phase of component (C1), (a) At least one solid antioxidant having a melting point above 20°C, (b) First surfactant; and (c) Water in which the solid antioxidant is suspended A continuous aqueous phase including; (ii) A dispersed oil phase of component (C2), (d) at least one liquid antioxidant having a melting point of less than 20°C, and (e) A dispersed oil phase containing a second surfactant in which the liquid antioxidant is dispersed in water Includes, An aqueous antioxidant suspension emulsion wherein the solid antioxidant exists in the form of particles with a median particle size D50 of less than 10 μm, and the liquid antioxidant exists in the form of droplets with a median particle size D50 of less than 10 μm.

2. The aqueous antioxidant suspend emulsifier according to claim 1, wherein the solid antioxidant is present together with the liquid antioxidant in an amount of at least 20 wt%, preferably at least 30 wt%, based on the total weight of the aqueous antioxidant suspend emulsifier.

3. The aqueous antioxidant suspension emulsion according to claim 1 or 2, wherein the weight ratio of the solid antioxidant to the liquid antioxidant is in the range of 1:50 to 50:

1.

4. The aqueous antioxidant suspension emulsion according to claim 1 or 2, wherein the liquid antioxidant exists as droplets with a median particle size D50 of less than 5 μm, preferably less than 2 μm.

5. The aqueous antioxidant suspension emulsion according to claim 1 or 2, wherein the solid antioxidant exists as particles with a median particle size D50 of less than 5 μm, preferably less than 2 μm.

6. The aqueous antioxidant suspend emulsifier according to claim 1 or 2, wherein the first surfactant, together with the second surfactant, is present in an amount of 1 wt% to 10 wt%, preferably 3 wt% to 8 wt%, based on the total weight of the aqueous antioxidant suspend emulsifier.

7. The aqueous antioxidant suspension emulsion according to claim 6, wherein the first surfactant and the second surfactant are selected from the group consisting of nonionic surfactants, anionic surfactants, and combinations thereof.

8. The aqueous antioxidant suspension emulsion according to claim 1 or 2, wherein the first surfactant and / or the second surfactant is selected from the group consisting of methacrylate-methyl methacrylate-polyethylene glycol graft copolymer, tristyrylphenol ethoxylate, sulfated or phosphorylated tristyrylphenol ethoxylate and salts thereof, propylene oxide-ethylene oxide block copolymer, fully / partially saponified polyvinyl alcohol, alcohol ethoxylate, fatty alcohol sulfate, fatty alcohol ether sulfate, linear alkylbenzene sulfonate, oleate sulfonate, oleate, and stearate.

9. The aqueous antioxidant suspension emulsion according to claim 1 or 2, wherein the first surfactant and the second surfactant are the same surfactant.

10. The solid antioxidants are octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; dioctadecyl 3,3'-thiodipropionate; pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazine-2-ylamino)phenol; 3,3',3',5,5',5'-hexa-tert-butyl-a,a',a'-(mesitylene-2,4,6-triyl)tri-p- Cresol; reaction products with phenol, 4-methyl-, dicyclopentadiene and isobutylene; ethylenebis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate]; thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; N,N'-hexane-1,6-diylbis(3-3,5-di-tert-butyl-4-hydroxyphenylpropionamide); N,N'-bis(3,5-di-tert-butyl-4-hydroxyl-phenylpropionyl)hydrazine; 1,3,5-Tris[(4-tert-butyl-3-hydroxy-2,6-dimethylphenyl)methyl]-1,3,5-triazinan-2,4,6-trione; 2,2'-methylenebis(4-methyl-6-tert-butylphenol); Hexamethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; 1,3,5-Tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)trione;Butylated hydroxytoluene;2-(1,1-dimethylethyl)-6-[[3-(1,1-dimethylethyl)-2-hydroxy-5-methylphenylmethyl-4-methylphenyl acrylate;2,2-bis[3-(dodecylthio)-1-oxopropoxy]methyl]propane- The solid antioxidant is selected from the group consisting of 1,3-diylbis[3-(dodecylthio)propionate]; 2,4-bis(dodecylthiomethyl)-6-methylphenol; didodecyl-3,3'-thiodipropionate; and combinations thereof, and preferably the solid antioxidant is dioctadecyl 3,3'-thiodipropionate; 3,3',3',5,5',5'-hexa-tert-butyl-a,a',a'-(mesitylene-2,4,6 -Triyl)tri-p-cresol; 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazine-2-ylamino)phenol; reaction products with phenol, 4-methyl-, dicyclopentadiene and isobutylene; ethylenebis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate]; 1,3,5-tris[(4-tert-butyl-3-hydroxy A aqueous antioxidant suspension emulsion according to claim 1 or 2, selected from the group consisting of droxy-2,6-dimethylphenyl)methyl]-1,3,5-triazinan-2,4,6-trione; 2,2-bis[[3-(dodecylthio)-1-oxopropoxy]methyl]propane-1,3-diylbis[3-(dodecylthio)propionate]; 2,4-bis(dodecylthiomethyl)-6-methylphenol; and combinations thereof.

11. The liquid antioxidant is selected from the group consisting of 4,6-bis(octylthiomethyl)-o-cresol; 2,4-dimethyl-6-(1-methylpentadecyl)phenol; benzenepropanoic acid, 3,5-bis(1,1-dimethyl-ethyl)-4-hydroxy-C7-C9 branched alkyl esters; benzeneamine, reaction products with N-phenyl-, 2,4,4-trimethylpentene; ditridecyl 3,3'-thiodipropionate; benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, C13-15 branched and linear alkyl esters; and combinations thereof; preferably Alternatively, the aqueous antioxidant suspension emulsion according to claim 1 or 2, wherein the liquid antioxidant is selected from the group consisting of 4,6-bis(octylthiomethyl)-o-cresol; benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-C7-C9 branched alkyl ester; benzeneamine, reaction product with N-phenyl-,2,4,4-trimethylpentene; ditridecyl 3,3'-thiodipropionate; benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, C13-15 branched and linear alkyl esters; and combinations thereof.

12. The aqueous antioxidant suspension emulsion according to claim 1 or 2, comprising a half-hindered phenol antioxidant and a thio synergist.

13. The aqueous antioxidant suspension emulsion according to claim 1 or 2, further comprising at least one additive selected from the group consisting of thickeners, antifreezes, defoamers, rheology modifiers, preservatives, colorants, and inert fillers.

14. The aqueous antioxidant suspension emulsion according to claim 1 or 2, further comprising a light stabilizer.

15. The aqueous antioxidant suspension emulsion according to claim 1 or 2, wherein the aqueous antioxidant suspension emulsion does not contain an organic solvent.

16. A process for preparing an aqueous antioxidant suspension emulsion: Step 1. Prepare a suspension of solid antioxidants by mixing at least one solid antioxidant having a melting point above 20°C and a first surfactant with water; Step 2. Prepare an oil-in-water emulsion of a second antioxidant by mixing at least one liquid antioxidant having a melting point of less than 20°C and a second surfactant with water; Step 3. Add the oil-in-water emulsion prepared in Step 2 to the suspension prepared in Step 1 under continuous stirring to prepare an aqueous antioxidant suspension emulsion; The solid antioxidant and the liquid antioxidant are homogenized until the median particle size D50 of the solid antioxidant and the liquid antioxidant is less than 10 μm. A process for preparing an aqueous antioxidant suspension emulsion containing [a specific substance].

17. A process for preparing an aqueous antioxidant suspension emulsion: Step 1. Prepare a suspension of solid antioxidants by mixing at least one solid antioxidant having a melting point above 20°C and a first surfactant with water; Step 2. Prepare a self-emulsifying concentrate of liquid antioxidants by mixing at least one liquid antioxidant having a melting point of less than 20°C with a second surfactant; Step 3. Prepare an aqueous antioxidant suspension emulsion by adding the self-emulsifying concentrate prepared in Step 2 to the suspension prepared in Step 1 under continuous stirring; Homogenize the solid antioxidant and the liquid antioxidant until the median particle size D50 of the solid antioxidant and the liquid antioxidant is less than 10 μm. A process for preparing an aqueous antioxidant suspension emulsion containing [a specific substance].

18. A process for preparing an aqueous antioxidant suspension emulsion according to claim 16 or 17, wherein the solid antioxidant and the liquid antioxidant are homogenized until the median particle size D50 of the solid antioxidant and the liquid antioxidant is less than 5 μm, preferably less than 2 μm.

19. A process for preparing the aqueous antioxidant suspension emulsion according to claim 16 or 17, wherein the solid antioxidant is homogenized by grinding in step 1.

20. A process for preparing the aqueous antioxidant suspension emulsion according to claim 16 or 17, wherein the solid antioxidant is homogenized under high shear in step 2.

21. An aqueous antioxidant suspension emulsion prepared according to the process described in claim 16 or 17.

22. Use of the aqueous antioxidant suspension emulsion according to claim 1 or 2 in stabilizing polymer materials.

23. A polymer composition, With polymers or copolymers in aqueous suspension or emulsion form; The aqueous antioxidant suspension emulsion according to claim 1 or 2 A polymer composition containing [a specific compound].