CN117777368A - A high pH cationic polyacrylate antibacterial emulsion and its preparation and an interior wall coating without adding antiseptic antibacterial agents and its preparation - Google Patents

Abstract

The invention belongs to the technical field of coatings, and discloses a high-pH cationic polyacrylate antibacterial emulsion, a preparation method thereof, an inner wall coating without antiseptic antibacterial agent addition and a preparation method thereof. The emulsion comprises the following raw materials: emulsifying agent, initiator, sodium bicarbonate, water, acrylic ester monomer, cationic monomer, methyl styrene isocyanate monomer and hyperbranched polyethyleneimine. The emulsion provided by the invention has strong alkalinity and strong cation property, can realize self corrosion prevention, and the paint prepared from the emulsion does not need to be additionally added with a corrosion-resistant antibacterial agent, has good storage stability, and is more environment-friendly and safer.

Description

A kind of high pH cationic polyacrylate antibacterial emulsion and its preparation and preservative-free antibacterial Agent-added interior wall coating and its preparation

Technical field

The invention belongs to the technical field of coatings, and more specifically, relates to a high pH cationic polyacrylate antibacterial emulsion and its preparation, as well as an interior wall coating without adding antiseptic antibacterial agents and its preparation.

Background technique

Water-based paint uses water as the dispersion medium and is rich in a large number of organic components such as cellulose and emulsions. It is easily corroded by microorganisms such as bacteria and mildew, which causes the paint to deteriorate, stink, and have abnormal viscosity. After the paint is applied to the wall, it will also breed mold in a damp and dark environment for a long time, causing the wall to turn black and fall off, seriously endangering the home environment.

The anti-corrosion technology of coatings is usually obtained by adding anti-corrosion and antibacterial agents to the coating formula. Currently, common antiseptic and antibacterial agents are divided into inorganic antibacterial agents, organic antibacterial agents and a small amount of photocatalytic agents. in:

Inorganic antibacterial agents mainly use silver, copper and zinc as the main raw materials. These antibacterial agents have broad spectrum but short antibacterial effect, and the release of these free metal ions into the environment will seriously harm the growth of aquatic organisms and endanger environmental health. Organic antibacterial agents are mainly represented by isothiazolinones and their derivatives, which have good bactericidal effects. However, studies have shown that such preservatives contain potential contact allergies and can cause contact dermatitis in humans and produce severe allergic reactions. In addition, isothiazolinone compounds can enter the body through human contact, directly or indirectly affecting normal hormone metabolism, and their metabolites and conversion products often show certain biological activity and bioaccumulation. Other antibacterial agents, such as photocatalytic ones, need to be excited by ultraviolet light to produce antibacterial activity. Their application conditions are limited and their preparation costs are high, so they are not widely applicable.

One of the current directions in the preparation of antibacterial coatings is to modify polymer emulsions and embed materials with antibacterial functions in physical or chemical ways to make the emulsions and the coatings they prepare antibacterial. Among them: (1) The small molecule antibacterial agent is directly mixed with the polymer emulsion by physical mixing. The preparation process is simple, but the combination fastness of the small molecule antibacterial agent and the polymer emulsion is poor, and the antibacterial agent is easy to dissolve, such as the invention of CN105949900B The patent discloses a method for preparing a water-based antibacterial coating containing silver sulfide nanoparticles. The preparation method is simple. The aqueous solution of a hybrid material loaded with silver sulfide nanoparticles with antibacterial functions is directly added to the water-based resin dispersion, and then the additive is added. Water-based coatings with antibacterial functions can be prepared by mixing the plasticizer and pigment evenly. However, the hybrid material of silver sulfide nanoparticles and the water-based resin dispersion are only physically doped, resulting in problems of poor bonding strength and poor emulsion stability. (2) The antibacterial monomer is chemically bonded to the emulsion polymer macromolecular chain to make the prepared emulsion more stable. CN113136003B discloses a method for preparing a styrene-acrylic antibacterial emulsion containing a thiazole structure. The monomers containing a thiazole structure are chemically combined into the macromolecular chain of the polymer emulsion to impart long-lasting antibacterial properties to the emulsion. There is no need to add additional bactericides during application. However, studies have shown that thiazole structural substances are irritating to human skin and eyes, are harmful to the body after being absorbed through the skin and ingested, and are not environmentally friendly.

In summary, it can be seen that the current anti-corrosion of coatings is mainly through adding anti-corrosion and anti-bacterial agents directly into the paint. However, there is a risk of poor anti-bacterial durability and easy dissolution of anti-bacterial agents, and most anti-corrosion and anti-bacterial agents are harmful to the human body and the environment. Antibacterial modification of emulsions is a new approach. However, the current antibacterial modification of emulsions generally involves the introduction of antibacterial materials into the emulsion through physical or chemical combination. Common methods include inorganic small molecule antibacterial agents (such as metal ions and their compounds), cationic antibacterial materials (such as quaternary ammonium salt antibacterial agents) and other antibacterial materials such as antibacterial agents containing thiazole structures, organic guanidines, natural chitosan, etc. are introduced into emulsion polymerization, and there are also many problems. Therefore, it is urgent to come up with a new method to modify the emulsion so that it has antibacterial properties. Not only can the emulsion be protected from bacterial and virus erosion during storage, but the coatings prepared with it do not require the addition of additional preservatives. , the prepared coating is more environmentally friendly and safer.

Contents of the invention

The purpose of the present invention is to propose a high pH cationic polyacrylate antibacterial emulsion and its preparation in view of the shortcomings of the existing technology, and an interior wall coating without antiseptic and antibacterial agents added and its preparation. The emulsion of the present invention has both strong alkaline and strong cationic properties, and can realize its own anti-corrosion. The coating prepared by the emulsion does not need to add additional anti-corrosion and antibacterial agents, has good storage stability, and the coating is more environmentally friendly and safe.

In order to achieve the above object, the first aspect of the present invention provides a high pH cationic polyacrylate antibacterial emulsion. The raw materials of the emulsion include the following components: emulsifier, initiator, sodium bicarbonate, water, acrylate monomers monomer, cationic monomer, methylstyrene isocyanate monomer and hyperbranched polyethyleneimine.

In the present invention, the emulsion prepared by the present invention has both high pH and high cationic properties. Since the pH of the environment suitable for the growth of most bacteria is weakly acidic to weakly alkaline, in a strong alkaline environment, the protein of the microorganism will be denatured, making it difficult to survive. At the same time, the positive charge in the emulsion can adsorb the negatively charged cell membrane and interact with the bacterial cell membrane. The interaction of negative charges destroys the integrity of the bacterial cell wall, causes cell membrane imbalance, and inhibits the activity of intracellular enzymes, ultimately leading to bacterial death. Therefore, with the dual blessing of high pH and cationic properties of the emulsion of the present invention, the emulsion itself can have antibacterial function, and the coating prepared by it does not need to add additional preservatives.

On the one hand, the present invention introduces polyethyleneimine, which is highly alkaline and cationic in aqueous solution, and uses methacryloyloxyethyltrimethylammonium chloride as a cationic monomer, which is bonded to polyacrylate through emulsion polymerization. In the emulsion, the emulsion prepared by this method has both strong alkalinity and cationicity. The cationicity can be provided by polyethylenimine or cationic monomer. At the same time, the quaternary ammonium group in the cationic monomer has efficient bacteriostatic and bactericidal effects. , bacterial microorganisms cannot survive in strong alkaline and strong cationic solutions, and the two work synergistically to achieve the purpose of efficient bacteriostasis and antisepsis.

In the present invention, polyethyleneimine is divided into ordinary linear structure and highly branched structure. Hyperbranched polyethyleneimine is a polyethyleneimine with a highly branched structure. Compared with ordinary linear polyethyleneimine, the molecular structure of branched polyethyleneimine is more dispersed and complex. The number and length of branch chains are also more diverse, with a large number of amine groups, and better physical and chemical properties. .

According to the present invention, preferably the pH of the emulsion is 10.5-11.5.

According to the present invention, preferably, the raw materials of the emulsion include the following components: 1-2 parts by weight of emulsifier, 1-2 parts by weight of initiator, 0.5-1.0 parts by weight of sodium bicarbonate, 500-600 parts by weight of water, acrylic acid 100-400 parts by weight of ester monomer, 1-3 parts by weight of cationic monomer, 40-50 parts by weight of methylstyrene isocyanate monomer and 40-50 parts by weight of hyperbranched polyethyleneimine.

According to the present invention, preferably, the emulsifier is an anionic emulsifier, and preferably, the anionic emulsifier is at least one of sodium dodecyl sulfonate, sodium dodecyl sulfate and ammonium dodecyl sulfate.

According to the present invention, preferably, the initiator is potassium persulfate and/or ammonium persulfate.

According to the present invention, preferably, the acrylate monomer is a soft monomer and/or a hard monomer; preferably, the soft monomer is at least one of ethyl acrylate, butyl acrylate and isooctyl acrylate. species; preferably, the hard monomer is methyl methacrylate and/or ethyl methacrylate; preferably, the ratio of the soft monomer to the hard monomer is (1.5-2.5): (0.8-1.2 ).

According to the present invention, preferably, the cationic monomer is methacryloyloxyethyltrimethylammonium chloride.

According to the present invention, preferably, the hyperbranched polyethyleneimine is a hyperbranched polyethyleneimine with an average molecular weight of 1,200, a hyperbranched polyethyleneimine with an average molecular weight of 1,800, and a hyperbranched polyethyleneimine with an average molecular weight of 10,000. At least one.

The second aspect of the present invention provides a method for preparing the high pH cationic polyacrylate antibacterial emulsion, the preparation method comprising: mixing the emulsifier, initiator, sodium bicarbonate, water, acrylic ester monomer, cationic monomer, methyl styrene isocyanate monomer and hyperbranched polyethyleneimine and performing emulsion polymerization to obtain the high pH cationic polyacrylate antibacterial emulsion.

According to the present invention, preferably, the preparation method comprises the following steps:

S1: Mix acrylate monomer, cationic monomer, part of emulsifier and part of water, stir evenly and emulsify to obtain pre-emulsion A;

S2: Mix and react methylstyrene isocyanate monomer, hyperbranched polyethyleneimine, other emulsifiers and other water to obtain pre-emulsion B;

S3: preparing an initiator aqueous solution; heating and mixing sodium bicarbonate, a portion of the initiator aqueous solution and a portion of the pre-emulsion A to obtain a first emulsion system, and after the first emulsion system emits blue light, mixing the blue light emulsion system with another portion of the pre-emulsion A and another portion of the initiator aqueous solution, and keeping the temperature to obtain a second emulsion system;

S4: Keep the temperature of step S3 unchanged, mix the second emulsion system, pre-emulsion B and the remaining initiator aqueous solution and keep them warm, and then sequentially cool down, filter and discharge to obtain the high pH cationic Polyacrylate antibacterial lotion.

In the present invention, the high pH cationic polyacrylate antibacterial emulsion of the present invention includes three types of monomers, namely, the present invention uses acrylate monomers as the main monomer and methylbenzene modified with hyperbranched polyethyleneimine. Ethylene isocyanate monomer (ie, pre-emulsion B) is the functional monomer, and methacryloyloxyethyltrimethylammonium chloride is the cationic monomer.

According to the present invention, preferably, in step S1:

The stirring speed is 800-1200r/min;

The emulsification time is 25-35min.

According to the present invention, preferably, in step S2:

The temperature of the reaction is 20-30°C, and the time is 12-36h;

The dosage ratio of the part of the emulsifier to the other part of the emulsifier is (1.5-2.5): (0.8-1.2);

The usage ratio of the part of water to the other part of water is (1.5-2.5): (0.8-1.2).

According to the present invention, preferably, in step S3:

The mass concentration of the initiator in the initiator aqueous solution is 0.5-1.5%;

The temperature increase is such that the temperature at which step S3 is performed is 70-80°C;

The keeping time is 1-1.5h;

The dosage ratio of a part of the initiator aqueous solution, another part of the initiator aqueous solution and the remaining part of the initiator aqueous solution is (0.8-1.2): (0.8-1.2): (0.8-1.2);

The dosage ratio of the part of the pre-emulsion liquid A to the other part of the pre-emulsion liquid A is (0.8-1.2): (1.5-2.5).

According to the present invention, preferably, in step S4:

The keeping time is 1-1.5h;

Cool down to 35-45°C.

The third aspect of the present invention provides an interior wall coating without the addition of antiseptic and antibacterial agents. The interior wall coating includes the following components: water, cellulose ether and its derivatives, auxiliaries, the high pH cationic polymer Acrylic antibacterial emulsion, and optionally pigments and fillers.

According to the present invention, preferably, the interior wall coating includes the following components: 20-30 parts by weight of water, 0.5-1.0 parts by weight of cellulose ether and its derivatives, 2-4 parts by weight of additives, high pH cationic polymer 20-30 parts by weight of acrylic antibacterial emulsion and 40-45 parts by weight of pigments and fillers.

According to the present invention, preferably, the cellulose ether and its derivatives are at least one of hydroxyethyl cellulose, methyl hydroxyethyl cellulose, ethyl hydroxyethyl cellulose and methyl hydroxypropyl cellulose.

According to the present invention, preferably, the pigment and filler is at least one of titanium dioxide, kaolin and calcium carbonate.

According to the present invention, preferably, the auxiliary agent is at least one of a wetting agent, a dispersant, a pH regulator, a film-forming auxiliary agent, an antifreeze agent and a defoaming agent. Preferably, the pH regulator is an organic amine pH regulator and/or an inorganic pH regulator; preferably, the film-forming aid is an alcohol ester film-forming aid and/or a mixed ester film-forming aid. agent; preferably, the antifreeze is a surfactant antifreeze and/or an alcohol ether antifreeze; preferably, the defoamer is a mineral oil defoamer and/or a silicone defoamer. Foaming agent.

The fourth aspect of the present invention provides a method for preparing the interior wall paint without the addition of antiseptic and antibacterial agents. The preparation method of the interior wall paint includes mixing the water, cellulose ether and its derivatives, auxiliaries, and high pH. Cationic polyacrylate antibacterial emulsion and optional pigments and fillers are mixed and stirred evenly to prepare the interior wall coating.

The beneficial effects of the technical solution of the present invention are as follows:

1. The present invention creatively introduces hyperbranched polyethyleneimine and methacryloyloxyethyltrimethylammonium chloride (cationic monomer) into the emulsion polymer, wherein:

(1) Polyethyleneimine contains a large number of highly reactive and protonatable amine groups, and its aqueous solution is strongly alkaline. The protonation of the amine groups makes the polyethyleneimine aqueous solution carry a large number of positive charges, which is similar to methylstyrene. The product of the reaction of isocyanate monomers can undergo free radical polymerization with acrylate monomers to bond polyethyleneimine to emulsion macromolecules;

(2) Methacryloyloxyethyl trimethyl ammonium chloride is a cationic monomer having a reactive unsaturated double bond and a quaternary ammonium group. When reacted with the emulsion macromolecule, the emulsion can be endowed with an antibacterial quaternary ammonium salt group.

(3) The synergistic effect of polyethyleneimine and cationic monomers creatively endows the emulsion with strong alkaline and strong cationic properties, achieving the purpose of efficient antibacterial and antiseptic properties, and enabling the emulsion to have its own antiseptic properties during transportation and storage.

2. Use the emulsion prepared in the present invention as a raw material to prepare interior wall paint. The strong alkalinity and strong cationicity of the emulsion make it unnecessary to add additional anti-corrosion and antibacterial agents to the prepared paint, which can simplify the paint preparation process, achieve anti-corrosion in the paint tank, and make the paint more effective. After coating, the paint film is still strongly alkaline, and the quaternary ammonium groups in the paint film are chemically bonded to the emulsion macromolecular chain and will not dissolve easily, giving the paint film lasting antibacterial properties.

3. The raw materials used to prepare the emulsion of the present invention are easily available on the market and are relatively low in price. The prepared emulsion has the characteristics of ultra-low VOC, low odor, good weather resistance, etc., and is suitable for the preparation of high-grade latex paint for interior walls.

4. The polyethyleneimine and cationic monomer used in the present invention have low biological toxicity and will not cause irritation to the skin. The prepared emulsion and coating are more environmentally friendly and safe.

Other features and advantages of the present invention will be described in detail in the following detailed description.

Detailed ways

The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

In the following embodiments:

The dispersant was purchased from Shenzhen Haichuan New Material Technology Co., Ltd. (Dispersant 5040);

The pH regulator is a 20% sodium hydroxide aqueous solution;

The film-forming aid is a mixed ester film-forming aid, which is LOCA DA from Shengxingxing Chemical (Shanghai) Co., Ltd.;

The antifreeze agent is a surfactant antifreeze agent (Shanghai Haochang Fine Chemical Co., Ltd. FT100XTRIM);

The defoaming agent is mineral oil and the defoaming agent is BASF (China) Co., Ltd. ST 2410 mineral oil defoaming agent;

Methacryloyloxyethyltrimethylammonium chloride was purchased from Aladdin Reagent (Shanghai) Co., Ltd.; methylstyrene isocyanate monomer was purchased from Guangzhou Haoyi New Material Technology Co., Ltd.;

Hyperbranched polyethyleneimine (average molecular weight 1800) was purchased from Aladdin Reagent (Shanghai) Co., Ltd.

Example 1

This embodiment provides a high pH cationic polyacrylate antibacterial emulsion. The raw materials of the emulsion include the following components: 1.5 parts by weight of emulsifier sodium dodecyl sulfate, 1.5 parts by weight of initiator potassium persulfate, and hydrogen carbonate. 0.5 parts by weight of sodium, 530 parts by weight of deionized water, 250 parts by weight of soft monomer butyl acrylate, 125 parts by weight of hard monomer methyl methacrylate, cationic monomer methacryloyloxyethyltrimethylammonium chloride 1.5 parts by mass, 45 parts by mass of methylstyrene isocyanate monomer and 45 parts by mass of hyperbranched polyethyleneimine (average molecular weight 1800).

The preparation method of the high pH cationic polyacrylate antibacterial emulsion includes the following steps:

S1: Stir the acrylic monomer, cationic monomer, 2/3 emulsifier and 2/3 deionized water vigorously at a speed of 1000r/min, mix evenly, and take an emulsification time of 30 minutes to obtain pre-emulsion A;

S2: Mix methylstyrene isocyanate monomer, hyperbranched polyethyleneimine, 1/3 emulsifier and 1/3 deionized water at 25°C for 24 hours to obtain pre-emulsion B;

S3: Dissolve the initiator in deionized water to prepare an initiator aqueous solution with a mass concentration of 1%; raise the temperature to 80°C, and add 1/3 of the initiator aqueous solution and 1/3 of the initiator solution to the sodium bicarbonate at 80°C. Emulsion A, obtain the first emulsion system. After the first emulsion system emits blue light, add 2/3 of pre-emulsion A and 1/3 of the initiator aqueous solution dropwise to the emulsion system that emits blue light for about 2 hours. After the addition is completed, keep the temperature for 1 hour to obtain the second emulsion system;

S4: Keep the temperature at 80°C unchanged, add pre-emulsion B and 1/3 of the initiator aqueous solution dropwise into the second emulsion system, keep it warm for 1 hour, then lower the temperature to 40°C, filter, and discharge to obtain the above High pH cationic polyacrylate antimicrobial emulsion.

Example 2

This embodiment provides an interior wall coating without antiseptic and antibacterial agents. The interior wall coating includes the following components: 28.2 parts by weight of deionized water, 0.5 parts by weight of hydroxyethyl cellulose, and auxiliaries (1.0 parts by weight of dispersant) , 0.2 parts by weight of pH regulator, 1.0 parts by weight of film-forming aid, 0.5 parts by weight of antifreeze agent and 0.6 parts by weight of defoaming agent, 0 parts by weight of antiseptic and antibacterial agents), the high pH cationic polyacrylate antibacterial agent of Example 1 25 parts by weight of emulsion, pigments and fillers (25 parts by weight of titanium dioxide, 10 parts by weight of calcined kaolin and 8 parts by weight of 1250 mesh calcium carbonate).

The preparation method of the interior wall coating without adding antiseptic and antibacterial agent comprises:

(1) Mix dispersant, antifreeze agent, hydroxyethyl cellulose, pH regulator, 1/2 defoaming agent, and 2/3 deionized water, adjust the rotation speed to 800r/min, and mix for 10 minutes to obtain a premix.

(2) Add pigments and fillers to the premixed solution in step (1), and disperse at a high speed of 1500 r/min for 15 min to obtain a slurry.

(3) The rotation speed is reduced to 800 r/min, and the high pH cationic polyacrylate antibacterial emulsion, film-forming aid, 1/2 defoamer, and 1/3 deionized water of Example 1 are evenly mixed for 10 minutes to obtain the interior wall paint.

Example 3 and Comparative Examples 1-3 respectively provide an interior wall coating. The specific ingredients and dosage are shown in Table 1. Among them, the antiseptic and antibacterial agents of Comparative Example 1 and Comparative Example 2 were both manufactured by Thor Specialty Chemicals (Zhenjiang) Co., Ltd. RSC and LANXESS (Changzhou) Co., Ltd. are prepared to be composed of multiple BM5s, and RSC:BM5=1:4.

Table 1

test case

This test example tests the emulsion of Example 1, the interior wall coatings of Examples 2-3, and the interior wall coatings of Comparative Examples 1-3, including: thermal storage stability, low-temperature film-forming properties, wash resistance, and resistance to flooding. Alkalinity, anti-blooming salt-alkalinity, VOC and free formaldehyde content detection.

in:

The test method for the thermal storage stability of the emulsion is: take a certain amount of emulsion and place it in a 50°C oven, store it for 1 week, 2 weeks and 1 month respectively, observe whether the emulsion has abnormal phenomena such as demulsification, corruption, gelation, discoloration, etc., and test the pH change of the emulsion.

The test method for thermal storage stability of interior wall coatings is as follows: conduct viscosity, pH, and whiteness tests on Examples 2-3 and Comparative Examples 1-3 before thermal storage, and record the can opening status and test results, and then test them on After storage at 50°C for 1 week, 2 weeks, and 1 month, conduct viscosity, pH, and whiteness tests, and record the can opening status and test results.

The results of thermal storage stability of Examples 1-3 and Comparative Examples 1-3 are shown in Table 2.

Low-temperature film-forming test method: conducted in accordance with the relevant regulations of GBT 9756-2018. The results are shown in Table 3.

Washing resistance test method: conducted in accordance with the relevant provisions of GBT 9756-2018, the results are shown in Table 4.

The test methods for resistance to efflorescence and salt-alkali resistance are carried out according to JG/T 210-2018. The results are shown in Table 5. VOC and free formaldehyde content testing was conducted in accordance with GB 18582-2008, and the results are shown in Table 6.

Table 2

It can be seen from Table 2:

The emulsion of Example 1 has good storage stability, and the pH can remain relatively stable during hot storage. The coatings of Examples 2 and 3 have better storage stability, and the pH can remain relatively stable during hot storage. The coatings of Comparative Examples 1 and 2 are ordinary emulsions with in-can preservatives added, and their storage stability is also good. The coating of Comparative Example 3 is an ordinary emulsion without in-can preservatives added. After storage at 50°C for 2 weeks, the state of the can opening began to become abnormal, with thinning viscosity, abnormal odor, and flocculation.

table 3

Performance Example 2 Example 3 Comparative example 1 Comparative Example 2 Comparative example 3 Low temperature film forming property No abnormality No abnormality No abnormality No abnormality No abnormality

Table 4

Performance Example 2 Example 3 Comparative example 1 Comparative example 2 Comparative example 3 Washing resistance/time >6000 >6000 >6000 >6000 ＞6000

table 5

Table 6

As can be seen from Tables 3-6, Examples 2 and 3 use the self-made high pH cationic polyacrylate antibacterial emulsion of the present invention without adding any additional preservatives, and their low-temperature film-forming properties, resistance to efflorescence, resistance to salt and alkali efflorescence, and washability are all normal, and VOC and free formaldehyde are not detected.

The embodiments of the present invention have been described above. The above description is illustrative, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims (10)

1. A high pH cationic polyacrylate antibacterial emulsion, characterized in that the raw materials of the emulsion include the following components: an emulsifier, an initiator, sodium bicarbonate, water, an acrylate monomer, a cationic monomer, methyl styrene isocyanate monomer and a hyperbranched polyethyleneimine. 2. The high pH cationic polyacrylate antibacterial emulsion according to claim 1, wherein: The pH of the emulsion is 10.5-11.5; The raw materials of the emulsion include the following components: 1-2 parts by weight of an emulsifier, 1-2 parts by weight of an initiator, 0.5-1.0 parts by weight of sodium bicarbonate, 500-600 parts by weight of water, 100-400 parts by weight of an acrylic ester monomer, 1-3 parts by weight of a cationic monomer, 40-50 parts by weight of methyl styrene isocyanate monomer and 40-50 parts by weight of hyperbranched polyethyleneimine. 3. The high pH cationic polyacrylate antibacterial emulsion according to claim 1 or 2, wherein, The emulsifier is an anionic emulsifier. Preferably, the anionic emulsifier is at least one of sodium lauryl sulfate, sodium lauryl sulfate and ammonium lauryl sulfate; The initiator is potassium persulfate and/or ammonium persulfate; The acrylate monomer is a soft monomer and/or a hard monomer; preferably, the soft monomer is at least one of ethyl acrylate, butyl acrylate, and isooctyl acrylate; preferably, the soft monomer is The hard monomer is methyl methacrylate and/or ethyl methacrylate; preferably, the ratio of the soft monomer to the hard monomer is (1.5-2.5): (0.8-1.2); The cationic monomer is methacryloyloxyethyl trimethyl ammonium chloride; The hyperbranched polyethyleneimine is at least one of hyperbranched polyethyleneimine with an average molecular weight of 1,200, hyperbranched polyethyleneimine with an average molecular weight of 1,800, and hyperbranched polyethyleneimine with an average molecular weight of 10,000. 4. The preparation method of the high pH cationic polyacrylate antibacterial emulsion according to any one of claims 1-3, characterized in that the preparation method includes: adding the emulsifier, initiator, sodium bicarbonate, Water, acrylate monomer, cationic monomer, methylstyrene isocyanate monomer and hyperbranched polyethyleneimine are mixed and emulsion polymerized to obtain the high pH cationic polyacrylate antibacterial emulsion. 5. The preparation method of high pH cationic polyacrylate antibacterial emulsion according to claim 4, wherein the preparation method includes the following steps: S1: mixing and emulsifying acrylic acid ester monomers, cationic monomers, a portion of emulsifiers and a portion of water to obtain a pre-emulsion A; S2: mixing and reacting methyl styrene isocyanate monomer, hyperbranched polyethyleneimine, other emulsifiers and other water to obtain a pre-emulsion B; S3: Prepare an initiator aqueous solution; heat up and mix sodium bicarbonate, a part of the initiator aqueous solution and a part of the pre-emulsion A to obtain the first emulsion system. After the first emulsion system glows with blue light, use the blue-light emulsified liquid It is mixed with other parts of pre-emulsion A and another part of initiator aqueous solution and kept warm to obtain the second emulsion system; S4: Keep the temperature of step S3 unchanged, mix the second emulsion system, pre-emulsion B and the remaining initiator aqueous solution and keep them warm, and then sequentially cool down, filter and discharge to obtain the high pH cationic Polyacrylate antibacterial lotion. 6. The preparation method of high pH cationic polyacrylate antibacterial emulsion according to claim 5, wherein, In step S1: The stirring speed is 800-1200r/min; The emulsification time is 25-35min; In step S2: The reaction temperature is 20-30°C and the reaction time is 12-36h; The dosage ratio of the part of the emulsifier to the other part of the emulsifier is (1.5-2.5): (0.8-1.2); The usage ratio of the part of water to the other part of water is (1.5-2.5): (0.8-1.2); In step S3: The mass concentration of the initiator in the initiator aqueous solution is 0.5-1.5%; The temperature increase is such that the temperature at which step S3 is performed is 70-80°C; The insulation time is 1-1.5h; The dosage ratio of a part of the initiator aqueous solution, another part of the initiator aqueous solution and the remaining part of the initiator aqueous solution is (0.8-1.2): (0.8-1.2): (0.8-1.2); The dosage ratio of part of the pre-emulsion A to other parts of the pre-emulsion A is (0.8-1.2): (1.5-2.5); In step S4: The keeping time is 1-1.5h; Cool down to 35-45°C. 7. An interior wall coating without antiseptic and antibacterial agents, characterized in that the interior wall coating includes the following components: water, cellulose ether and its derivatives, auxiliaries, any one of claims 1-3 The high pH cationic polyacrylate antibacterial emulsion optionally includes pigments and fillers. 8. The interior wall coating without antiseptic and antibacterial agents according to claim 7, wherein the interior wall coating includes the following components: 20-30 parts by weight of water, 0.5-1.0 parts by weight of cellulose ether and its derivatives , 2-4 parts by weight of additives, 20-30 parts by weight of high pH cationic polyacrylate antibacterial emulsion, and 40-45 parts by weight of pigments and fillers. 9. The interior wall coating without antiseptic and antibacterial agents according to claim 7 or 8, wherein, The cellulose ether and its derivatives are at least one of hydroxyethyl cellulose, methyl hydroxyethyl cellulose, ethyl hydroxyethyl cellulose and methyl hydroxypropyl cellulose; The pigment and filler is at least one of titanium dioxide, kaolin and calcium carbonate; The auxiliary agent is at least one of a wetting agent, a dispersant, a pH regulator, a film-forming auxiliary agent, an antifreeze agent and a defoaming agent; Preferably, the pH adjuster is an organic amine pH adjuster and/or an inorganic pH adjuster; Preferably, the film-forming aid is an alcohol ester film-forming aid and/or a mixed ester film-forming aid; Preferably, the antifreeze is a surfactant antifreeze and/or an alcohol ether antifreeze; Preferably, the defoaming agent is a mineral oil defoaming agent and/or a silicone defoaming agent. 10. The method for preparing the interior wall paint without adding preservatives and antibacterial agents as described in any one of claims 7 to 9 is characterized in that the method for preparing the interior wall paint comprises mixing and stirring the water, cellulose ether and its derivatives, additives, high pH cationic polyacrylate antibacterial emulsion and optional pigments and fillers to obtain the interior wall paint.