Acrylate emulsion as well as preparation method and application thereof

Abstract

The invention discloses an acrylate emulsion as well as a preparation method and application thereof, the acrylate emulsion provided by the invention is polymerized by adopting a seed emulsion polymerization technology, and an amide group with an aldehyde removal effect, an ethylenic bond type unsaturated monomer containing an epoxy group and a carboxyl group and a monoethylenic bond type hydrolyzable organic silicon monomer are introduced in the polymerization process, so that the acrylate emulsion is prepared. And adding an anti-aldehyde auxiliary agent after polymerization, and the like. Emulsion paint prepared from the emulsion has excellent freeze-thaw stability, extremely low VOC and SVOC emission, excellent normal and low temperature scrubbing, low temperature thick coating cracking resistance (especially on loose putty) and no yellowing of a paint film without adding an anti-freezing agent, can effectively adsorb formaldehyde, and has extremely high comprehensive cost performance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of high polymer coatings, and particularly relates to an acrylate emulsion, a preparation method thereof and application thereof. BACKGROUND

[0002] In recent years, with the increasing concern about health problems, indoor air quality attracts more and more attention. It is reported that indoor air pollution is much more serious than outdoor air pollution. Indoor air pollutants mainly come from various volatile organic compounds (VOCs) emitted by building materials, specifically including volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs). The control standards of volatile organic compounds (VOCs) in building materials are becoming increasingly stringent. At the same time, the control requirements of semi-volatile organic compounds (SVOCs) are also constantly improving internationally. SVOC is an organic liquid or solid that can slowly evaporate at normal temperature and pressure. Although its evaporation rate is slower than that of VOC, it is difficult to degrade and has strong adsorption, and often accumulates in indoor environments, causing persistent harm to human health. To address this problem, the international community has issued a revised version of the ISO 11890-2:2020 standard to regulate the detection method of SVOC. China is also optimizing the detection standard GB / T 23986-2009 and the limit standard GB 18582-2020 to control SVOC. However, in order to ensure the performance of latex paint, various additives need to be added during the preparation of latex paint, and the additives usually contain VOC or SVOC.

[0003] Formaldehyde, as one of the common pollutants in indoor air, has a serious impact on people's health, especially the carcinogenicity. The relatively closed indoor environment is easy to accumulate the amount of formaldehyde in the air. When the content of formaldehyde in the air reaches 0.1 mg / m 3 , it will produce an odor, making the human body feel uncomfortable; when it reaches 0.6 mg / m 3 , it will make the human body feel more uncomfortable, and the throat and eyes will also feel uncomfortable; the higher the concentration of formaldehyde, the more obvious the discomfort of the human body, and the body will produce corresponding rejection, nausea, vomiting and other adverse symptoms, and even serious enough to cause death.

[0004] The main methods to control indoor formaldehyde at present are ventilation method, physical adsorption and chemical adsorption, etc. In the field of chemical adsorption, the development of acrylate emulsion with formaldehyde absorption function is a widely researched topic in building emulsion, especially interior wall emulsion. Such emulsion is prepared by copolymerization of functional monomers that can react with formaldehyde, and plays an important role in water-based emulsion system.

[0005] Patent CN 118599065A discloses an NPA formaldehyde-removing waterborne acrylic emulsion and its preparation method. It uses functional substances such as polyamino o-carbamoylbenzoic acid and polyhydroxy o-phenyl glycidyl ether to improve the formaldehyde adsorption capacity through acylation and amino modification, and improves the weather resistance and mechanical properties of the emulsion through copper powder catalysis. It achieves good adhesion, viscosity and coating density of waterborne acrylic ester, and has the function of highly efficient formaldehyde adsorption, thus improving the environmental protection and safety of the product.

[0006] Patent CN 116082560A discloses an environmentally friendly, high-efficiency formaldehyde-removing styrene-acrylic emulsion for interior walls and its preparation method. It contains a specific proportion of styrene, acrylate, methacrylate, alkyl acrylate crosslinking monomer, functional acrylic monomer, functional crosslinking monomer, emulsifier, initiator, buffer, and rapid formaldehyde removal additive. It is prepared by a pre-emulsification semi-continuous automatic dripping process, achieving a long-lasting formaldehyde removal effect from paint making to construction and occupancy. It can react with formaldehyde under normal temperature conditions, continuously purify formaldehyde in the air, and significantly reduce the harm of formaldehyde in interior decoration.

[0007] Patent CN 105504146 A discloses a formaldehyde-absorbing emulsion and its preparation method, containing methyl methacrylate, styrene, n-butyl acrylate, functional monomers, emulsifiers and initiators. Through a specific preparation method, a coating with formaldehyde adsorption capacity is formed. The synergistic effect of functional monomers and emulsifiers enhances the formaldehyde adsorption capacity, effectively adsorbs formaldehyde, reduces indoor formaldehyde concentration, reduces health risks to the human body, and reduces environmental pollution during the production process.

[0008] Patent CN 119241762 A discloses a formaldehyde-absorbing pure acrylic emulsion with odor-reducing properties, its raw material composition, preparation method, and application. It uses a specific raw material composition and preparation method, including acetyl acetoxyethyl methacrylate and / or adipic acid dihydrazide as functional monomers, combined with a specific emulsifier and dropwise reaction process. Through oxidation-reduction post-treatment and stripping process, an ultra-low VOC and residual monomer content formaldehyde-absorbing pure acrylic emulsion is prepared, which has excellent formaldehyde absorption effect and durability, meeting the needs of high-quality environmentally friendly coatings.

[0009] The aforementioned patents all employ different methods to prepare acrylic emulsions with formaldehyde removal functions, focusing primarily on functionality, namely, excellent formaldehyde absorption effect and durability, without much attention to application performance, such as the balance between low-temperature scrubbing, resistance to low-temperature thick coating cracking, and yellowing of the paint film, thus possessing both functionality and application performance.

[0010] With the increasing awareness of health and environmental protection among people, and the continuous improvement of environmental protection standards at home and abroad, future interior wall coating products will inevitably move towards environmental protection and human-friendly products, and be developed in the direction of formaldehyde-resistant, low VOC and SVOC, and high-performance coatings. Summary of the Invention

[0011] The main objective of this invention is to provide an acrylic emulsion, its preparation method, and its application. Latex paint prepared from this emulsion has excellent freeze-thaw stability, extremely low VOC and SVOC emissions, excellent room and low temperature scrubbing performance, and resistance to low temperature thick coating cracking (especially on loose putty) without the addition of antifreeze. The paint film does not yellow and can also effectively adsorb formaldehyde, resulting in a very high overall cost performance.

[0012] To achieve the above-mentioned objectives, the present invention provides an acrylic emulsion comprising the following components in parts by weight:

[0013] Component a): 15.0-30.0 parts of at least one monovinyl aromatic monomer and / or at least one C1-C4 alkyl ester of methacrylic acid;

[0014] Component b): at least one C2-C of acrylic acid 10 Alkyl esters, 20.0-40.0 parts;

[0015] Component c): at least one α,β-monoene bond unsaturated C3-C6 monocarboxylic acid, 0.5-1.5 parts;

[0016] Component d): 1.0-2.5 parts of at least one acrylamide and / or alkylacrylamide;

[0017] Component e): at least one acetoacetyl-functionalized olefinic unsaturated monomer, 1.5-3.5 parts;

[0018] Component f): at least one mono-olefinic unsaturated hydrolyzable organosilicon monomer, 0.1-1.0 parts;

[0019] Component g): 0.1-1.5 parts of at least one glycidyl monoester of a monoolefinic unsaturated C3-C8 acid having one or two epoxy groups.

[0020] Component h): at least one anti-aldehyde additive, 0.5-2.5 parts.

[0021] The anti-aldehyde additive is a prepolymer of polyamine and polycarboxylic acid.

[0022] In a preferred embodiment, component a) is 15.0-25.0 parts, component b) is 25.0-35.0 parts, component c) is 0.5-1.0 parts, component d) is 1.0-2.0 parts, component e) is 2.0-3.5 parts, component f) is 0.2-0.8 parts, component g) is 0.5-1.5 parts, and component h) is 1.0-2.0 parts.

[0023] In a preferred embodiment, the monovinyl aromatic monomer in component a) includes one or more of styrene, 2-methylstyrene, 4-methylstyrene, 2-n-butylstyrene, 4-n-butylstyrene, and 4-n-decylstyrene; optionally, it is styrene.

[0024] In a preferred embodiment, the C2-C of acrylic acid in component b) 10 Alkyl esters include one or more of ethyl acrylate, n-butyl acrylate, n-hexyl acrylate, n-octyl acrylate, isooctyl acrylate, and 2-propylheptyl acrylate; optionally, they are n-butyl acrylate or isooctyl acrylate.

[0025] In a preferred embodiment, the α,β-monoolefinic unsaturated C3-C6 monocarboxylic acid in component c) includes one or more of acrylic acid, methacrylic acid, butenoic acid, 2-ethylacrylic acid, and 2-propylacrylic acid; optionally, it is acrylic acid or methacrylic acid.

[0026] In a preferred embodiment, the acrylamide and / or acrylamide derivative in component d) include one or more of acrylamide, methacrylamide, N-ethylacrylamide, N-propylacrylamide, N-isopropylacrylamide, and N-butylacrylamide; optionally, it is acrylamide or methacrylamide.

[0027] In a preferred embodiment, the acetylacetyl functionalized olefin unsaturated monomer in component e) has the following structural formula:

[0028]

[0029] in:

[0030] a and b are each independently 0 or 1, but not both zero at the same time. Preferably, a is 0 or 1 and b is 1.

[0031] X and Y can be either O or N independently, with X being O and Y being O being preferred.

[0032] R6 is C 1-4 -alkyl, preferably methyl;

[0033] R5 is H or C 1-4 -alkyl group, preferably H;

[0034] R4 is C 1-4 -alkylene, preferably methylene or ethylene;

[0035] R1, R2, and R3 are independently selected from H and C. 1-4 -alkyl, preferably methyl or ethyl, more preferably H and methyl.

[0036] In a preferred embodiment, the acetoacetyl functionalized olefin unsaturated monomer includes one or more of acetoacetoxyethyl methacrylate, acetoacetoxypropyl methacrylate, allyl acetoacetate, and acetoacetoxypropyl acrylate.

[0037] In a preferred embodiment, the monoolefinically unsaturated hydrolyzable organosilicon monomer in component f) includes one or more of vinyltrialkoxysilane, alkylvinyldialkoxysilane, and methacryloxyalkyltrialkoxysilane.

[0038] Optionally, the monoolefinically unsaturated hydrolyzable organosilicon monomer in component f) includes one or more of vinyltrimethoxysilane, methylvinyldialkoxysilane, methacryloxypropyltrimethoxysilane, and methacryloxypropyltriethoxysilane, and may further be vinyltrimethoxysilane.

[0039] In a preferred embodiment, the glycidyl monoester of the mono-olefinic unsaturated C3-C8 acid having one or two epoxy groups in component g) includes one or more of glycidyl acrylate and glycidyl methacrylate, optionally glycidyl methacrylate.

[0040] In a preferred embodiment, in the anti-formaldehyde additive of component h), the polycarboxylic acid is a homopolymer or copolymer of acrylic acid, methacrylic acid, itaconic acid, and maleic acid; and the polyamine is selected from one or more combinations of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and hexamethylenediamine.

[0041] Optionally, the anti-aldehyde additive can be polymerized using polymerization methods known in the art, such as free radical polymerization.

[0042] In a preferred embodiment, the method for preparing the anti-aldehyde additive is as follows: first, a polycarboxylic acid is prepared, and then a polyamine is added to the polycarboxylic acid, followed by a free radical polymerization reaction in the presence of an initiator.

[0043] In some specific embodiments of the present invention, the method for preparing the anti-aldehyde additive is as follows: water is added to the reaction vessel by free radical polymerization, the temperature is raised to 70-95°C, an initiator is added to the bottom of the vessel, and the reaction is carried out for a period of time. Then, the polymer monomer, oxidant solution and reducing agent solution are added dropwise simultaneously. After the addition is completed, the temperature is kept warm for a period of time, and after cooling to 65-75°C, residual monomer is removed. Then, a diluted polyamine aqueous solution is added dropwise for high-temperature neutralization. After cooling and filtration, the anti-aldehyde additive is obtained.

[0044] In a preferred embodiment, the acrylate emulsion further includes a solvent, wherein the solvent is water.

[0045] Optionally, the acrylate emulsion has a solids content of 49%-51%.

[0046] Optionally, the acrylate emulsion is prepared by free radical emulsion polymerization of the above components.

[0047] A second aspect of the present invention provides a method for preparing the above-mentioned acrylate emulsion, comprising the following steps:

[0048] A pre-emulsion A is obtained by mixing components a), b), c), d), e), f), and g, and a base solution B containing a first emulsifier and a polymerization inhibitor is prepared, as well as an initiator solution C. The raw materials containing the pre-emulsion A, base solution B, and initiator solution C are subjected to a free radical emulsion polymerization reaction. After the reaction is completed, a second emulsifier and an anti-aldehyde additive are added, and the pH value is adjusted to obtain the acrylate emulsion.

[0049] Furthermore, the preparation method includes the following steps:

[0050] Add the first part of pre-emulsion A and the first part of initiator solution C to the base solution B to obtain the first stage reactant. Continue to add the remaining second part of pre-emulsion A and the second part of initiator solution C to the first stage reactant to obtain the second stage reactant. After the reaction is completed, add the second emulsifier and anti-aldehyde additive, adjust the pH value, and then separate the solid and liquid to obtain the acrylate emulsion.

[0051] In the above-described stages and steps of the present invention:

[0052] First, a seed emulsion is prepared by adding the first part of the pre-emulsion A and the first part of the initiator solution C to the substrate solution B to obtain the seed emulsion. Then, the remaining second part of the pre-emulsion A and the second part of the initiator aqueous solution C are added dropwise simultaneously. The seeds absorb the monomers and continue to grow until the emulsion is completely added.

[0053] After the seeds are prepared, the polymer segments are prepared by double-drop application. Various functional monomers, such as components c), d), e), f), and g), are added to the pre-emulsion. Component f) enables micro-crosslinking between polymer segments. Component c) provides ionic crosslinking and introduces carboxyl groups onto the polymer segments. Component g) contains both double bonds and epoxy groups; the double bonds participate in polymerization, and the epoxy groups crosslink with the carboxyl groups during polymer film formation, providing suitable cohesive force and giving the latex paint good resistance to cracking in thick putty coatings. Components d) and e) contain amide groups and double bonds; the double bonds participate in polymerization, while the amide groups can chemically react with formaldehyde, thus performing formaldehyde removal.

[0054] Then, a second emulsifier and an anti-formaldehyde additive are added to the reaction product, and the pH value is adjusted. The addition of the second emulsifier not only improves the freeze-thaw stability of the emulsion, but also greatly improves the freeze-thaw stability of the latex paint, as well as the dispersibility between the emulsion and pigments and fillers. This allows the formulation to avoid the addition of antifreeze agents and requires less dispersant, which are important sources of VOCs and SVOCs, thus achieving effective control. The addition of the anti-formaldehyde additive plays the following roles: First, this additive does not contain VOCs or SVOCs, avoiding environmental pollution; second, the additive structure contains both primary and secondary amines. Primary amines can react with formaldehyde, improving formaldehyde absorption efficiency, while secondary amines can catalyze the reaction of primary amines, further improving formaldehyde absorption efficiency. It can also promote the reaction of components d) and e) with formaldehyde, reducing the content of residual amines and the proportion of conjugated groups. These are all causes of yellowing, thus effectively controlling the yellowing of latex paint, achieving multiple effects of low VOCs and SVOCs, low yellowing, and high formaldehyde absorption.

[0055] In a preferred embodiment, the first part of the preemulsion A has a mass percentage of 2%-6% based on the total amount of preemulsion A, and the second part of the preemulsion A has a mass percentage of 94%-98%.

[0056] In a preferred embodiment, the first part accounts for 40%-60% of the total mass of the initiator solution C, and the second part accounts for 60%-40% of the total mass of the initiator solution C.

[0057] In a preferred embodiment, the first emulsifier is an anionic emulsifier, preferably an emulsifier with low SVOC content (because SVOC in the emulsifier is one of the important sources of SVOC in the final emulsion). Suitable anionic emulsifiers are selected from at least one of sodium polyoxyethylene ether sulfate, sodium dodecylbenzene sulfonate, sodium dodecyl diphenyl ether sulfonate, and sodium alkyl succinate sulfonate, and more preferably sodium polyoxyethylene ether sulfate with a branched or isomeric alcohol structure.

[0058] In a preferred embodiment, the second emulsifier is a nonionic emulsifier, and a suitable nonionic emulsifier is preferably a polyoxyethylene ether containing a polycyclic benzene ring structure.

[0059] Preferably, the initiator is a water-soluble initiator, including but not limited to at least one of ammonium persulfate, sodium persulfate, and potassium persulfate, more preferably ammonium persulfate.

[0060] Preferably, the polymerization inhibitor is one or more of TEMPO and hydroquinone.

[0061] Preferably, the amount of the polymerization inhibitor added is 5-15 ppm of the mass of the base liquid B.

[0062] In a preferred embodiment, the method for preparing preemulsion A includes: mixing a portion of the first emulsifier, component d), and water evenly, and then sequentially adding components a), b), c), e), f), and g), mixing evenly, and setting aside.

[0063] The mass ratio of component d) to water is 1-2:50-110.

[0064] In a preferred embodiment, the method for preparing the base liquid B includes: adding the remaining first emulsifier, polymerization inhibitor and water to a reaction vessel, and heating to 82-90°C for later use; wherein the mass ratio of polymerization inhibitor to water is 0.001-0.01:40-100.

[0065] In a preferred embodiment, the method for preparing initiator solution C includes: mixing 0.2-0.8 parts by weight of initiator with 7.0-40 parts by weight of water, and setting aside for later use.

[0066] In a preferred embodiment, the raw materials comprising the pre-emulsion A, the bottom liquid B, and the initiator solution C are subjected to a free radical emulsion polymerization reaction, including the following steps:

[0067] At 82-90℃, the first part of pre-emulsion A and the first part of initiator solution C are added to the base liquid B in one go. After reacting for 5-10 minutes, the remaining second part of pre-emulsion A and the second part of initiator solution C are added dropwise simultaneously, ensuring that the initiator drop time is longer than the pre-emulsion drop time. After the drop is completed, keep warm for 15-45 minutes and then cool down to 70-75℃.

[0068] Add the second emulsifier to the reactor and disperse for 10-15 minutes. Then add the post-treatment agent dropwise. After the agent has been added, keep the temperature at 45-55℃ for 15-30 minutes.

[0069] A neutralizing agent is added dropwise to the reaction vessel to adjust the pH value to 7.0-9.0. Then, an anti-aldehyde agent, an antifoaming agent, and a bactericide are added. After filtration, the acrylate emulsion is obtained.

[0070] Specifically, the post-treatment agent includes, but is not limited to, at least one of tert-butyl hydroperoxide (T-BHP), tert-amyl hydroperoxide (T-AHP), sodium bisulfite, sodium dithionite, and isoascorbic acid, preferably tert-butyl hydroperoxide and / or isoascorbic acid, more preferably tert-butyl hydroperoxide and isoascorbic acid in a mass ratio of 2:1; the amount of the post-treatment agent is 0.1-1.0 parts by mass based on 100 parts by mass of the prepared acrylic emulsion;

[0071] Preferably, the defoamer is conventional in the field, including but not limited to at least one of mineral oil defoamer NXZ, BASF A10, Tego825, and BYK028; Tego825 is optional, and the amount of the defoamer is 0.0002-0.001 parts by weight based on 100 parts by weight of the prepared acrylic emulsion.

[0072] Preferably, the bactericide is common in the field, including but not limited to at least one of KATHON LX 150, KORDEK, QK-20, and BIT; optionally, QK-20 and BIT are compounded, and the amount of the bactericide is 0.0001-0.0045 parts by weight based on 100 parts by weight of the prepared acrylic emulsion.

[0073] In this article, the preparation processes of the pre-emulsion A, the substrate solution B, and the initiator solution C are not sequential. Pre-emulsion A, comprising a mixture of various monomers, is the main component participating in the polymerization reaction. Substrate solution B primarily consists of process water, a very small amount of polymerization inhibitor, and a portion of emulsifier. This emulsifier mainly controls the seed emulsion particle size to obtain the final target particle size emulsion. The polymerization inhibitor prevents premature initiation of some monomers, ensuring uniform particle size distribution and good batch stability. Initiator solution C, the initiator decomposes upon heating to generate free radicals, inducing free radical polymerization of the monomers.

[0074] The third aspect of the present invention provides the application of the acrylate emulsion or the acrylate emulsion prepared by the preparation method described above in formaldehyde-removing latex paint.

[0075] Compared with the prior art, the present invention has the following advantages:

[0076] The acrylic emulsion provided by this invention introduces multiple functional monomers, such as components c), d), e), f), and g), into the pre-emulsion. Then, a second emulsifier and an anti-formaldehyde additive h) are added to the reaction product. Component f) creates a micro-crosslinked state between polymer segments. Component c) provides ionic crosslinking and introduces carboxyl groups onto the polymer segments. Component g) contains both double bonds and epoxy groups. The double bonds participate in polymerization, and the epoxy groups crosslink with the carboxyl groups during polymer film formation, providing suitable cohesive force and giving the latex paint good resistance to cracking of thick putty coatings. Components d) and e) contain amide groups and double bonds. The double bonds participate in polymerization, while the amide groups can chemically react with formaldehyde, thus performing formaldehyde removal. Component h) contains both primary and secondary amines. The primary amine can react with formaldehyde, and the secondary amine can catalyze the reaction of the primary amine, improving formaldehyde absorption efficiency.

[0077] Specifically, the anti-formaldehyde additive component f) has a unique structure; it is a mixture of polycarboxylic acid and polyamine. The polyamine structure contains both primary and secondary amines, has a high boiling point, and does not introduce VOCs or SVOCs. The primary amine can react chemically with formaldehyde, and the secondary amine can catalyze the reaction of the primary amine. Components d) and e) also contain primary amines and can similarly catalyze the reaction, significantly improving formaldehyde absorption efficiency and reducing residual amine content and the proportion of conjugated groups—all factors that cause yellowing. This effectively controls the yellowing of latex paint, achieving multiple effects: low VOCs and SVOCs, low yellowing, and high formaldehyde absorption. Component c) is a carboxylic acid functional monomer that improves polymerization stability and introduces carboxylic acid groups into the polymer chain. Component d) is an amine functional monomer that provides a sterically hindered stabilization mechanism for the reaction of primary amines with formaldehyde and greatly enhances the calcium ion stability of the emulsion. Combined with component c), the emulsion exhibits excellent calcium ion stability and mechanical stability. Components e), f), and g) are all crosslinking monomers. Component f) can introduce aldehyde-removing groups and improve the density of the paint film. Component f) puts the polymer chain segments in a micro-crosslinked state and can also improve the adhesion of the paint film to the substrate. The epoxy group in component g) crosslinks with the carboxylic acid group in component c) during the film formation process, which can improve the cohesive force between paint films and reduce the hydrophilicity of the paint film. The synergistic effect of the three different crosslinking monomers gives the paint film excellent scrub resistance at room temperature and low temperature and resistance to low temperature thick coating cracking.

[0078] In addition, a second emulsifier is added to the reaction product. This emulsifier is a non-ionic emulsifier that does not contain SVOC. Its addition can greatly improve the freeze-thaw stability of the emulsion and latex paint. There is no need to add antifreeze in the paint formulation (antifreeze is also a source of VOC), which reduces the amount of dispersant used. At the same time, it does not affect the room temperature and low temperature scrubbing of latex paint, thus improving cost performance.

[0079] The acrylate emulsion of the present invention employs a pre-emulsification semi-continuous dripping process, which can effectively improve polymerization stability and allow the chemical reaction to proceed under relatively mild conditions.

[0080] Other features and advantages of the present invention will be described in detail through the following specific embodiments. Detailed Implementation

[0081] The following embodiments are provided to better understand this application and are not limited to the preferred embodiments described herein. They 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 features of this application with other prior art, falls within the scope of protection of this application.

[0082] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0083] Unless otherwise specified, the "%" used in the following examples refers to mass percentage. The following describes some of the raw materials used in the examples and comparative examples:

[0084] Anti-formaldehyde additive: homemade

[0085] Preparation method of anti-aldehyde additive:

[0086] Anti-formaldehyde additive 1: Add 85g of deionized water to a polymerization reactor equipped with a stirrer, condenser, constant flow pump feeding device, and constant flow drip metering device. Heat to 80℃, add 0.2g of sodium hypophosphite aqueous solution as reducing agent from the bottom of the reactor, react for 5 minutes, and then simultaneously add 40g of acrylic acid monomer, 0.2g of ammonium persulfate aqueous solution as oxidant, and 0.3g of sodium hypophosphite aqueous solution as reducing agent. Control the addition to complete in about 3.5 hours. After the addition is completed, keep warm for 35 minutes, cool to 65℃, and then treat to remove residual monomers. Then add diluted diethylenetriamine aqueous solution for high-temperature neutralization, cool, filter, and discharge to obtain anti-formaldehyde additive 1.

[0087] Anti-formaldehyde additive 2: Add 85g of deionized water to a polymerization reactor equipped with a stirrer, condenser, constant flow pump feeding device, and constant flow drip metering device. Heat to 80℃, add 0.2g of sodium hypophosphite aqueous solution as reducing agent from the bottom of the reactor, react for 5 minutes, and then simultaneously add 40g of methacrylic acid monomer, 0.2g of ammonium persulfate aqueous solution as oxidant, and 0.3g of sodium hypophosphite aqueous solution as reducing agent. Control the addition to complete in about 3.5 hours. After the addition is completed, keep warm for 35 minutes, cool to 65℃, and then treat to remove residual monomers. Then add diluted tetraethylenepentamine aqueous solution for high-temperature neutralization, cool down, filter and discharge to obtain anti-formaldehyde additive 2.

[0088] Anti-formaldehyde additive 3: Add 85g of deionized water to a polymerization reactor equipped with a stirrer, condenser, constant flow pump feeding device, and constant flow drip metering device. Heat to 80℃, add 0.2g of sodium hypophosphite aqueous solution as reducing agent from the bottom of the reactor, react for 5 minutes, then simultaneously add 40g of a mixture of acrylic acid and methacrylic acid monomers, 0.2g of ammonium persulfate aqueous solution as oxidant, and 0.3g of sodium hypophosphite aqueous solution as reducing agent. Control the addition to complete in about 3.5 hours. After the addition is complete, keep warm for 35 minutes, cool to 65℃, and then treat to remove residual monomers. Then add diluted tetraethylenepentamine aqueous solution for high-temperature neutralization, cool, filter, and discharge to obtain anti-formaldehyde additive 3.

[0089] Sodium hydroxide is a product of Sinopharm Corporation;

[0090] Acetyl acetyl methacrylate (AAEM) is a product of Hefeng Chemical Co., Ltd.

[0091] Vinyltriethoxysilane (A-171) is a product of Nanjing Chenggong Organosilicon Materials Co., Ltd.

[0092] Glycidyl methacrylate (GMA) is a product of Aladdin Company;

[0093] FES993 (anionic emulsifier) ​​is a product of BASF.

[0094] TS200 (nonionic emulsifier) ​​is a product of Clariant Chemicals Ltd.

[0095] The polymerization inhibitor TEMPO is a product of Aladdin Company;

[0096] Tego028, the defoamer, is a product of Digo Company.

[0097] The fungicides QK-20 and BIT are products of Lonza Corporation.

[0098] Example 1

[0099] This embodiment provides an acrylic emulsion, the preparation method of which is as follows:

[0100] 1) Preparation of preemulsion A: At room temperature and pressure, add 1.4g FES-993, 1.2g acrylamide and 45g deionized water to a preemulsion tank equipped with a monomer metering tank and a stirrer. After stirring and dissolving thoroughly, add 3g methyl methacrylate, 12g styrene, 14g n-butyl acrylate, 7g isooctyl acrylate, 0.6g methacrylic acid, 1.8g AAEM, 0.2g GMA and 0.15g A-171 in sequence, and stir thoroughly to mix well before use.

[0101] 2) Preparation of bottom solution B (bottom solution): Add 0.16g FES-993, 0.005g TEMPO and 40g deionized water to the polymerization reactor equipped with a stirrer, condenser, constant flow pump feeding device and constant flow drip metering device, stir thoroughly to dissolve, and heat to 82℃ inside the polymerization reactor.

[0102] 3) Preparation of initiator solution C: At room temperature and pressure, add 0.2g of ammonium persulfate and 18g of deionized water to an initiator container equipped with a stirrer and a constant flow dripping device, and stir until completely dissolved for later use;

[0103] 4) When the temperature inside the reactor reaches 82℃, add 6% of the total amount of pre-emulsion A and 50% of the initiator solution to the reactor in sequence. React for 5 minutes under stirring. Then, add the remaining pre-emulsion A and initiator solution C dropwise to the reactor through a constant flow pump feeding device. Ensure that the dropwise addition time of initiator solution C is longer than that of pre-emulsion A during the dropwise addition process. After the dropwise addition is completed, keep the temperature for 15 minutes and then cool down to 70℃.

[0104] 5) Add 1.0g TS200 to the reactor, disperse for 10min, and then add the post-treatment agent dropwise, namely 0.1g aqueous solution of tert-butyl hydrogen peroxide and 0.08g aqueous solution of sodium bisulfite. After the dropwise addition is complete, keep the temperature for 20min and then cool down to 45℃.

[0105] 6) Add NaOH solution as a neutralizing agent to the reaction vessel to adjust the pH value to 7.5;

[0106] 7) Add 0.8g of anti-aldehyde additive 1, 0.06g of defoamer (Tego 028, the same below), and 1.1g of bactericide (0.2g of QK-20 and 0.9g of BIT, the same below) to the reaction vessel, and obtain the acrylate emulsion after filtration.

[0107] Example 2

[0108] This embodiment provides an acrylic emulsion, the composition of which and its specific preparation method are as follows:

[0109] 1) Preparation of preemulsion A: At room temperature and pressure, add 1.65g FES-993, 1.8g acrylamide and 80g deionized water to a preemulsion tank equipped with a monomer metering tank and a stirrer. After stirring and dissolving thoroughly, add 5g methyl methacrylate, 20g styrene, 15g n-butyl acrylate, 15g isooctyl acrylate, 0.8g methacrylic acid, 2.8g AAEM, 1.0g GMA and 0.6g A-171 in sequence, and stir thoroughly to mix well before use.

[0110] 2) Preparation of bottom liquid B (bottom liquid): Add 0.24g FES-993, 0.007g TEMPO and 80g deionized water to the polymerization reactor equipped with a stirrer, condenser, constant flow pump feeding device and constant flow drip metering device, stir and dissolve thoroughly, and heat to 84℃ inside the polymerization reactor.

[0111] 3) Preparation of initiator solution C: At room temperature and pressure, add 0.5g of ammonium persulfate and 31g of deionized water to an initiator container equipped with a stirrer and a constant flow dripping device, and stir until completely dissolved for later use;

[0112] 4) When the temperature inside the reactor reaches 84℃, add 2% of the total amount of core layer preemulsion A and 40% of the initiator solution to the reactor in sequence. React for 10 minutes under stirring. Then, add the remaining preemulsion A and initiator solution C dropwise to the reactor through a constant flow pump feeding device. Ensure that the dropwise addition time of initiator solution C is longer than that of preemulsion A during the dropwise addition process. After the dropwise addition is completed, keep the temperature for 45 minutes and then cool down to 72℃.

[0113] 5) Add 1.3g TS200 to the reactor, disperse for 10min, and then add the post-treatment agent dropwise, namely an aqueous solution of 0.5 tert-butyl hydrogen peroxide and an aqueous solution of 0.4g sodium bisulfite. After the dropwise addition is complete, keep the temperature for 25min and then cool down to 45℃.

[0114] 6) Add NaOH solution as a neutralizing agent to the reaction vessel to adjust the pH value to 8.5;

[0115] 7) Add 1.2g of anti-aldehyde additive 2, 0.082g of defoamer (Tego 028, the same below), and 2.2g of bactericide (0.4g QK-20, 1.8g BIT, the same below) to the reaction vessel, and obtain the acrylate emulsion after filtration.

[0116] Example 3

[0117] This embodiment provides an acrylic emulsion, the composition of which and its specific preparation method are as follows:

[0118] 1) Preparation of preemulsion A: At room temperature and pressure, add 2.2g FES-993, 2.3g acrylamide and 105g deionized water to a preemulsion tank equipped with a monomer metering tank and a stirrer. After stirring and dissolving thoroughly, add 4g methyl methacrylate, 24g styrene, 30g n-butyl acrylate, 8g isooctyl acrylate, 1.0g methacrylic acid, 3.2g AAEM, 1.4g GMA and 0.95g A-171 in sequence, and stir thoroughly to mix well before use.

[0119] 2) Preparation of bottom solution B (bottom solution): Add 0.3g FES-993, 0.01g TEMPO and 90g deionized water to the polymerization reactor equipped with a stirrer, condenser, constant flow pump feeding device and constant flow drip metering device, stir thoroughly to dissolve, and heat to 90℃ inside the polymerization reactor.

[0120] 3) Preparation of initiator solution C: At room temperature and pressure, add 0.8g of ammonium persulfate and 30g of deionized water to an initiator container equipped with a stirrer and a constant flow dripping device, and stir until completely dissolved for later use;

[0121] 4) When the temperature inside the reactor reaches 90℃, add 3% of the total amount of core layer preemulsion A and 60% of the initiator solution to the reactor in sequence. React for 8 minutes under stirring. Then, add the remaining preemulsion A and initiator solution C dropwise to the reactor through a constant flow pump feeding device. Ensure that the dropwise addition time of initiator solution C is longer than that of preemulsion A during the dropwise addition process. After the dropwise addition is completed, keep the temperature for 30 minutes and then cool down to 75℃.

[0122] 5) Add 1.8g TS200 to the reactor, disperse for 10min, and then add the post-treatment agent dropwise, namely an aqueous solution of 1.0 tert-butyl hydrogen peroxide and an aqueous solution of 0.8g sodium bisulfite. After the dropwise addition is complete, keep the temperature for 30min and then cool down to 45℃.

[0123] 6) Add NaOH solution as a neutralizing agent to the reaction vessel to adjust the pH value to 9.0;

[0124] 7) Add 2.3g of anti-aldehyde additive 3, 0.12g of defoamer (Tego 028, the same below), and 3.1g of bactericide (0.6g QK-20, 2.5g BIT, the same below) to the reaction vessel, and obtain the acrylate emulsion after filtration.

[0125] Example 4

[0126] This embodiment provides an acrylic emulsion, the composition of which and its specific preparation method are as follows:

[0127] 1) Preparation of preemulsion A: At room temperature and pressure, add 1.5g FES-993, 1.1g acrylamide and 83g deionized water to a preemulsion tank equipped with a monomer metering tank and a stirrer. After stirring and dissolving thoroughly, add 3g methyl methacrylate, 15g styrene, 18g n-butyl acrylate, 7g isooctyl acrylate, 0.7g methacrylic acid, 2.2g AAEM, 0.6g GMA and 0.4g A-171 in sequence, and stir thoroughly to mix well before use.

[0128] 2) Preparation of bottom liquid B (bottom liquid): Add 0.2g FES-993, 0.004g TEMPO and 85g deionized water to the polymerization reactor equipped with a stirrer, condenser, constant flow pump feeding device and constant flow drip metering device, stir thoroughly to dissolve, and heat to 86℃ inside the polymerization reactor.

[0129] 3) Preparation of initiator solution C: At room temperature and pressure, add 0.6g of ammonium persulfate and 24g of deionized water to an initiator container equipped with a stirrer and a constant flow dripping device, and stir until completely dissolved for later use;

[0130] 4) When the temperature inside the reactor reaches 86℃, add 5% of the total amount of core layer preemulsion A and 33% of the initiator solution to the reactor in sequence. React for 7 minutes under stirring. Then, add the remaining preemulsion A and initiator solution C dropwise to the reactor through a constant flow pump feeding device. Ensure that the dropwise addition time of initiator solution C is longer than that of preemulsion A during the dropwise addition process. After the dropwise addition is completed, keep the temperature for 25 minutes and then cool down to 71℃.

[0131] 5) Add 1.5g TS200 to the reactor, disperse for 10min, and then add the post-treatment agent dropwise, namely, an aqueous solution of 0.3 tert-butyl hydrogen peroxide and an aqueous solution of 0.24g sodium bisulfite. After the dropwise addition is complete, keep the temperature for 15min and then cool down to 45℃.

[0132] 6) Add NaOH solution as a neutralizing agent to the reaction vessel to adjust the pH value to 8.0;

[0133] 7) Add 1.2g of anti-aldehyde additive 2, 0.076g of defoamer (Tego 028, the same below), and 1.7g of bactericide (0.3g QK-20, 1.4g BIT, the same below) to the reaction vessel, and obtain the acrylate emulsion after filtration.

[0134] Example 5

[0135] This embodiment provides an acrylic emulsion, the composition of which and its specific preparation method are as follows:

[0136] 1) Preparation of preemulsion A: At room temperature and pressure, add 2.05g FES-993, 1.9g acrylamide and 92g deionized water to a preemulsion tank equipped with a monomer metering tank and a stirrer. After stirring and dissolving thoroughly, add 5g methyl methacrylate, 19g styrene, 15g n-butyl acrylate, 17g isooctyl acrylate, 0.9g methacrylic acid, 3.2g AAEM, 1.3g GMA and 0.75g A-171 in sequence, and stir thoroughly to mix well before use.

[0137] 2) Preparation of bottom solution B (bottom solution): Add 0.27g FES-993, 0.008g TEMPO and 85g deionized water to the polymerization reactor equipped with a stirrer, condenser, constant flow pump feeding device and constant flow drip metering device, stir thoroughly to dissolve, and heat to 85℃ inside the polymerization reactor.

[0138] 3) Preparation of initiator solution C: At room temperature and pressure, add 0.7g of ammonium persulfate and 27g of deionized water to an initiator container equipped with a stirrer and a constant flow dripping device, and stir until completely dissolved for later use;

[0139] 4) When the temperature inside the reactor reaches 85℃, add 4% of the total amount of core layer preemulsion A and 50% of the initiator solution to the reactor in sequence. React for 6 minutes under stirring. Then, add the remaining preemulsion A and initiator solution C dropwise to the reactor through a constant flow pump feeding device. Ensure that the dropwise addition time of initiator solution C is longer than that of preemulsion A during the dropwise addition process. After the dropwise addition is completed, keep the temperature for 35 minutes and then cool down to 73℃.

[0140] 5) Add 1.7g TS200 to the reactor, disperse for 10min, and then add the post-treatment agent dropwise, namely, an aqueous solution of 0.7 tert-butyl hydrogen peroxide and an aqueous solution of 0.56g sodium bisulfite. After the dropwise addition is complete, keep the temperature for 20min and then cool down to 45℃.

[0141] 6) Add NaOH solution as a neutralizing agent to the reaction vessel to adjust the pH value to 8.0;

[0142] 7) Add 1.8g of anti-aldehyde additive 3, 0.102g of defoamer (Tego 028, the same below), and 2.6g of bactericide (0.5g of QK-20 and 2.1g of BIT, the same below) to the reaction vessel, and obtain the acrylate emulsion after filtration.

[0143] Example 6

[0144] This embodiment provides an acrylic emulsion. Compared with Example 2, the only difference is that 0.3g of A-171 is added to the pre-emulsion A. The other components and the emulsion preparation method are exactly the same as in Example 2.

[0145] Example 7

[0146] This embodiment provides an acrylic emulsion. Compared with Example 2, the only difference is that 0.7g of A-171 is added to the pre-emulsion A. The other components and the emulsion preparation method are exactly the same as in Example 2.

[0147] Example 8

[0148] This embodiment provides an acrylic emulsion. Compared with Example 2, the only difference is that 0.6g of GMA is added to the pre-emulsion A. The other components and the emulsion preparation method are exactly the same as in Example 2.

[0149] Example 9

[0150] This embodiment provides an acrylic emulsion. Compared with Example 2, the only difference is that 1.4g of GMA is added to the pre-emulsion A. The other components and the emulsion preparation method are exactly the same as in Example 2.

[0151] Example 10

[0152] This embodiment provides an acrylate emulsion. The only difference from Example 2 is that 1.0g of anti-aldehyde additive 2 is added to the reaction vessel. The other components and the emulsion preparation method are exactly the same as in Example 2.

[0153] Example 11

[0154] This embodiment provides an acrylate emulsion. Compared with Example 2, the only difference is that 1.8g of anti-aldehyde additive 2 is added to the reaction vessel. The other components and the emulsion preparation method are exactly the same as in Example 2.

[0155] Comparative Example 1

[0156] This comparative example provides an acrylic emulsion, which differs from Example 3 only in that A-171 and GMA are not added to the pre-emulsion A, and anti-aldehyde additive 3 is not added to the reaction vessel. The other components and the emulsion preparation method are exactly the same as those in Example 3.

[0157] Comparative Example 2

[0158] This comparative example provides an acrylate emulsion, which differs from Example 3 only in that A-171 is added to the pre-emulsion A but GMA is not added, and anti-aldehyde additive 3 is not added to the reaction vessel. The other components and the emulsion preparation method are exactly the same as those in Example 3.

[0159] Comparative Example 3

[0160] This comparative example provides an acrylic emulsion, which differs from Example 3 only in that GMA is added to the pre-emulsion A but not A-171, and anti-aldehyde additive 3 is not added to the reaction vessel. The other components and the emulsion preparation method are exactly the same as those in Example 3.

[0161] Comparative Example 4

[0162] This comparative example provides an acrylic emulsion. The only difference from Example 3 is that A-171 and GMA are not added to the pre-emulsion A, but anti-aldehyde additive 3 is added to the reaction vessel. The other components and the emulsion preparation method are exactly the same as those in Example 3.

[0163] Comparative Example 5

[0164] This comparative example provides an acrylic emulsion, which differs from Example 3 only in that A-171 and GMA are added to the pre-emulsion A, but anti-aldehyde additive 3 is not added to the reaction vessel. The other components and the emulsion preparation method are exactly the same as those in Example 3.

[0165] Comparative Example 6

[0166] This comparative example provides an acrylic emulsion, which differs from Example 3 only in that A-171 is added to the pre-emulsion A but GMA is not added, and anti-aldehyde additive 3 is added to the reaction vessel. The other components and the emulsion preparation method are exactly the same as those in Example 3.

[0167] Comparative Example 7

[0168] This comparative example provides an acrylic emulsion. The only difference from Example 3 is that A-171 is not added to the pre-emulsion A, but GMA is added, and anti-aldehyde additive 3 is added to the reaction vessel. The other components and the emulsion preparation method are exactly the same as those in Example 3.

[0169] Comparative Example 8

[0170] This comparative example provides an acrylic emulsion, which differs from Example 3 only in that AAEM is not added to the pre-emulsion A, but A-171 and GMA are added, and anti-aldehyde additive 3 is added to the reaction vessel. All other components and the emulsion preparation method are exactly the same as in Example 3. Test Example

[0171] Performance testing methods:

[0172] Freeze-thaw stability of latex paint: In accordance with GB / T 9756-2018 Synthetic Resin Emulsion Interior Wall Coatings, the sealed test sample was placed in a constant temperature chamber at (-7±2)℃ for 18 hours, and then taken out and placed in a constant temperature chamber at (23±2)℃ for 6 hours to thaw. The viscosity change was then observed.

[0173] Low-temperature thick coating: As required by the major customer, after the putty board is sanded smooth, it is pre-cooled at 5℃. 40g of paint is applied to the 20*30 board and then placed in a 5℃ constant temperature chamber overnight to observe whether cracks appear.

[0174] Scrub resistance: According to GB / T 9756-2018 Synthetic Resin Emulsion Interior Wall Coatings, two samples for comparison testing were coated with one coat of the test latex paint using a 120-micron line. After drying for 6 hours under standard conditions, another coat of the test latex paint was applied using an 80-micron line. The prepared test panels were then placed in a constant temperature and humidity room at a set temperature for 7 days to dry, and the number of scrub resistance cycles was tested.

[0175] Formaldehyde removal efficiency: According to "JC / T 1074-2008 Purification Performance of Indoor Air Purification Functional Coating Materials", 0.2g of coating was applied to a 0.25cm*4cm glass slide and cured for 7 days. The slide was then placed in a 1L bottle and sealed. 10 μL of 100ppm formaldehyde was added to the bottle and left for 24 hours. Then, 1mg of phenol reagent was diluted to 100mL, and 12.5g of the solution was diluted to 250mL. 10mL of this solution was added to the bottle and left for 2 hours. 5mL of this solution was then removed and 400 μL of ferric ammonium sulfate solution was added. The formaldehyde purification efficiency was obtained by comparing the absorbance.

[0176] Yellowing value △E: The prepared paint sample was divided into two parts. One part was stored at room temperature and the other part was stored in a 50°C oven. After four weeks, the heat-stored paint sample was taken out and a film was scraped on black and white card paper using a 200-micron wet film preparation tool. As a control, the paint sample stored at room temperature was scraped on black and white card paper using a 200-micron wet film preparation tool. After drying, the yellowing value of the two films was tested with an instrument.

[0177] The performance test results are shown in Table 1 below:

[0178] Table 1

[0179]

[0180] As shown in Table 1, the emulsion prepared using the embodiments of the present invention, when formulated into a odor-free and formaldehyde-removing latex paint, exhibits good freeze-thaw stability, low heat storage yellowing value, and no cracking when thickly coated on loose putty. It also demonstrates excellent room temperature and low temperature scrubbing performance and formaldehyde removal efficiency.

[0181] Compared with the reaction systems of the embodiments of the present invention, Comparative Example 1 did not contain A-171, GMA, or an anti-formaldehyde additive in its raw material components; Comparative Example 2 only contained A-171 in its raw material components, without GMA or an anti-formaldehyde additive; Comparative Example 3 only contained GMA in its raw material components, without A-171 or an anti-formaldehyde additive; Comparative Example 4 only contained an anti-formaldehyde additive in its raw material components, without A-171 or GMA; and Comparative Example 5 contained A-171 and GMA in its raw material components, without an anti-formaldehyde additive. In Comparative Example 6, A-171 and an anti-formaldehyde additive were added to the raw material components, but GMA was not added. In Comparative Example 7, GMA and an anti-formaldehyde additive were added to the raw material components, but A-171 was not added. In Comparative Example 8, AAEM was not added, but A-171, GMA, and an anti-formaldehyde additive were added. As shown in Table 1, the emulsions prepared from Comparative Examples 1-8, when formulated into odor-free and formaldehyde-removing latex paints, could not simultaneously achieve several core performance characteristics, such as freeze-thaw stability, normal and low-temperature scrubbing performance, low-temperature thick coating performance, latex paint yellowing, and formaldehyde removal efficiency.

[0182] 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. An acrylate emulsion, characterized in that, Components comprising the following parts by mass: Component a): at least one monovinyl aromatic monomer and / or at least one C1-C4 alkyl ester of methacrylic acid, 15.0-30.0 parts; Component b) at least one C2-C4-alkyl ester of acrylic acid, 20.0 to 40.0 parts; 10 alkyl ester of acrylic acid, 20.0 to 40.0 parts; Component c): at least one α,β-monoethylenically unsaturated C3-C6 monocarboxylic acid, 0.5-1.5 parts; Component d): at least one acrylamide and / or alkyl acrylamide 1.0-2.5 parts; Component e): at least one acetoacetyl-functional ethylenically unsaturated monomer, 1.5-3.5 parts; Component f): at least one monoethylenically unsaturated hydrolysable organosilicon monomer, 0.1-1.0 parts; Component g): at least one glycidyl monoester of a monoethylenically unsaturated C3-C8 acid having one or two epoxy groups, 0.1-1.5 parts, Component h): at least one anti-aldehyde additive, 0.5-2.5 parts; The anti-aldehyde additive is a prepolymer of a polyamine and a polycarboxylic acid.

2. The acrylate emulsion according to claim 1, characterized in that, The component a) is 15.0-25.0 parts, the component b) is 25.0-35.0 parts; the component c) is 0.5-1.0 parts, the component d) is 1.0-2.0 parts, the component e) is 2.0-3.5 parts, the component f) is 0.2-0.8 parts, the component g) is 0.5-1.5 parts, and the component h) is 1.0-2.0 parts; And / or, the monovinyl aromatic monomer in the component a) includes one or more of styrene, 2-methylstyrene, 4-methylstyrene, 2-n-butylstyrene, 4-n-butylstyrene, and 4-n-decylstyrene; optionally styrene; and / or the C2-C4 alkyl ester of acrylic acid in component b) is one or more of ethyl acrylate, n-butyl acrylate, n-hexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-propylheptyl acrylate; optionally n-butyl acrylate or isooctyl acrylate; 10 alkyl esters include one or more of ethyl acrylate, n-butyl acrylate, n-hexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-propylheptyl acrylate; optionally n-butyl acrylate or isooctyl acrylate; And / or, the α,β-monoethylenically unsaturated C3-C6 monocarboxylic acid in the component c) includes one or more of acrylic acid, methacrylic acid, crotonic acid, 2-ethylacrylic acid, 2-propylacrylic acid; optionally acrylic acid or methacrylic acid; And / or, the acrylamide and / or acrylamide derivative in the component d) includes one or more of acrylamide, methacrylamide, N-ethylacrylamide, N-propylacrylamide, N-isopropylacrylamide, N-butylacrylamide; optionally acrylamide or methacrylamide; And / or, the acetoacetyl-functional ethylenically unsaturated monomer in the component e) has the following structure: wherein: a and b are each independently 0 or 1, but not both zero, preferably a is 0 or 1, and b is 1; X and Y are each independently O or N, preferably X is O, Y is O; R6is C 1-4 - alkyl, preferably methyl; R5is H or C 1-4 - alkyl, preferably H; R4is C 1-4 - alkylene, preferably methylene or ethylene; R1, R2and R3are independently from each other selected from H and C 1-4 - alkyl, preferably methyl or ethyl, more preferably H and methyl; More preferably, the acetoacetyl-functional ethylenically unsaturated monomer includes one or more of acetoacetoxyethyl methacrylate, acetoacetoxypropyl methacrylate, allyl acetoacetate, acetoacetoxypropyl acrylate; And / or, the monoethylenically unsaturated hydrolysable organosilicon monomer in the component f) includes one or more of vinyltrialkoxysilane, alkylvinyl-dialkoxysilane, and methacryloyloxyalkyltrialkoxysilane; Optionally, the monoethylenically unsaturated hydrolysable organosilicon monomer in component f) comprises one or more of vinyltrimethoxysilane, methylvinyl dialkoxysilane, methacryloyloxypropyl trimethoxysilane and methacryloyloxypropyl triethoxysilane, further optionally vinyltrimethoxysilane; And / or, the glycidyl monoester of a mono- or di-epoxy group containing C3-C8 acid in component g) comprises one or more of glycidyl acrylate and glycidyl methacrylate, optionally glycidyl methacrylate.

3. The acrylate emulsion according to claim 1 or 2, characterized in that, In the anti-aldehyde assistant of component h), the polycarboxylic acid is a homopolymer or copolymer of acrylic acid, methacrylic acid, itaconic acid, maleic acid; the polyamine is a combination of one or more of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, hexamethylene diamine; Preferably, the preparation method of the anti-aldehyde assistant is: first, prepare the polycarboxylic acid, then add the polyamine to the polycarboxylic acid, and perform free radical polymerization in the presence of an initiator; More preferably, the preparation method of the anti-aldehyde assistant is: using free radical polymerization, water is added to the reaction kettle, heated to 70-95°C, the initiator is put into the kettle bottom, reacted for a period of time, then the polymerization monomer, oxidant solution and reducing agent solution are simultaneously added dropwise, after dropping, the temperature is kept for a period of time, then the temperature is lowered to 65-75°C, the residual monomer is treated and removed, then the diluted polyamine aqueous solution is added dropwise, high-temperature neutralization is carried out, the temperature is lowered, and the filtrate is obtained, which is the anti-aldehyde assistant.

4. The acrylate emulsion according to any one of claims 1 to 3, characterized in that, The solvent in the acrylate emulsion is water; And / or, the solid content of the acrylate emulsion is 49%-51%; And / or, the acrylate emulsion is prepared by free radical emulsion polymerization of the above components.

5. The preparation method of the acrylate emulsion according to any one of claims 1-4, comprising the following steps: Mixing the components a), b), c), d), e), f) and g) to obtain a pre-emulsion A, preparing a base liquid B containing a first emulsifier and a polymerization inhibitor, and preparing an initiator solution C; performing free radical emulsion polymerization reaction on raw materials containing the pre-emulsion A, the base liquid B and the initiator solution C, adding a second emulsifier, an anti-aldehyde assistant and adjusting the pH value after the reaction to obtain the acrylate emulsion.

6. The preparation method according to claim 5, characterized in that, Comprising the following steps: Adding the first part of the pre-emulsion A and the first part of the initiator solution C to the base liquid B to obtain a first-stage reactant, continuously adding the second part of the pre-emulsion A and the second part of the initiator solution C to the first-stage reactant to obtain a second-stage reactant, adding a second emulsifier, an anti-aldehyde assistant and adjusting the pH value after the reaction to obtain the acrylate emulsion by solid-liquid separation; Preferably, the mass percentage of the first part of the pre-emulsion A is 2%-6% based on the total amount of the pre-emulsion A, and the mass percentage of the second part of the pre-emulsion A is 94%-98%. Preferably, the first part accounts for 40-60% of the mass percentage of initiator solution C, and the second part accounts for 60-40% of the mass percentage of initiator solution C, based on the total amount of initiator solution C.

7. The preparation method according to claim 6, characterized in that, The first emulsifier is an anionic emulsifier, preferably the anionic emulsifier is at least one selected from polyoxyethylene ether sodium sulfate, sodium dodecylbenzenesulfonate, sodium dodecyl diphenyl ether sulfonate, and sodium alkyl succinate sulfonate, more preferably polyoxyethylene ether sodium sulfate with branched or isomeric alcohol structure; And / or, the second emulsifier is a non-ionic emulsifier, and suitable non-ionic emulsifiers are preferably selected from polyoxyethylene ethers containing polycyclic ring structures; And / or, the initiator is a water-soluble initiator, including but not limited to at least one of ammonium persulfate, sodium persulfate, and potassium persulfate, more preferably ammonium persulfate; And / or, the polymerization inhibitor is one or more of TEMPO and hydroquinone; And / or, the amount of polymerization inhibitor added is 5-15 ppm of the mass of the base solution B.

8. The preparation method according to claim 6 or 7, characterized in that, The mass ratio of component d) to water is 1-2:50-110; The mass ratio of polymerization inhibitor to water is 0.001-0.01:40-100.

9. The method of any one of claims 5-8, wherein, The second emulsifier is added to the reaction kettle and dispersed for 10-15 min, then the post-treatment agent is added dropwise, and after 15-30 min of insulation after dropwise addition is completed, the temperature is lowered to 45-55°C; The neutralizing agent is added dropwise to the reaction kettle, the pH value is adjusted to 7.0-9.0, then the anti-aldehyde additive, defoaming agent, and bactericide are added, and the acrylic ester emulsion is obtained after filtration; Preferably, the post-treatment agent includes but is not limited to at least one of tert-butyl hydroperoxide, tert-amyl hydroperoxide, sodium bisulfite, sodium hydrosulfite, and erythorbic acid, preferably tert-butyl hydroperoxide and / or erythorbic acid, more preferably tert-butyl hydroperoxide and erythorbic acid in a mass ratio of 2:1; the amount of the post-treatment agent is 0.1-1.0 parts by mass based on 100 parts by mass of the prepared acrylic emulsion.

10. The use of the acrylic ester emulsion of any one of claims 1-4 or the acrylic ester emulsion prepared by the preparation method of any one of claims 5-9 in an aldehyde-removing latex paint.

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