Mildew-proof and rot-proof water-based epoxy floor paint and preparation method thereof

Abstract

The application discloses a mildew-proof and rot-proof water-based epoxy floor paint and a preparation method thereof, and belongs to the technical field of water-based paints. First, the mildew-proof and rot-proof water-based epoxy floor paint comprises the following raw materials in mass percentage: modified water-based epoxy emulsion: 45.5-52.0%; water-based epoxy curing agent: 18.5-20.0%; mildew-proof microcapsule: 7.5-8.5%; silicon powder: 3.5-5.0%; nano zinc oxide: 2.5-3.0%; dispersant: 0.3-0.5%; defoaming agent: 0.1-0.3%; and the rest is deionized water. The application aims at solving the three technical problems of poor compatibility of a mildew-proof agent, insufficient long-term effect and decreased mechanical property of a coating of an existing water-based epoxy floor paint, and provides a water-based epoxy floor paint which is long-term mildew-proof and rot-proof, has high mechanical property and is environment-friendly through material design and process improvement.

Description

Technical Field

[0001] This invention belongs to the field of water-based coating technology, specifically relating to a mildew-proof and corrosion-resistant water-based epoxy floor coating and its preparation method. Background Technology

[0002] Waterborne epoxy floor coatings are gradually replacing traditional solvent-based products due to their environmental friendliness and low VOC content. However, in high-humidity or microbial-active environments, existing waterborne epoxy floor coatings are prone to mold and bacteria growth, leading to chalking, discoloration, and even peeling of the coating, severely affecting its service life and aesthetics.

[0003] Existing technologies mainly improve anti-mold performance by adding chemical anti-mold agents (such as isothiazolinones), but this has the following problems:

[0004] 1. Poor compatibility: The mildew inhibitor is not evenly dispersed in the water-based system and is prone to migrate to the coating surface and cause failure;

[0005] 2. Insufficient long-term effectiveness: Single antifungal agents are easily metabolized and decomposed by microorganisms in complex environments, and the antifungal period is usually less than 6 months;

[0006] 3. Decreased mechanical properties: Excessive addition of antifungal agents can damage the cross-linking structure of epoxy resin, leading to reduced adhesion and abrasion resistance.

[0007] With the surge in demand for cleanroom flooring from industries such as healthcare and food, developing a water-based epoxy floor coating that combines long-lasting mildew and corrosion resistance, high mechanical properties, and environmental friendliness is of significant practical importance. Summary of the Invention

[0008] This invention addresses the technical problems of poor compatibility, insufficient long-term effectiveness, and decreased coating performance of existing anti-mildew agents by proposing an anti-mildew and anti-corrosion water-based epoxy floor coating and its preparation method.

[0009] The objective of this invention can be achieved through the following technical solutions:

[0010] A mildew- and corrosion-resistant water-based epoxy floor coating comprises the following raw materials by weight percentage:

[0011] Modified waterborne epoxy emulsion: 45.5%–52.0%;

[0012] Water-based epoxy curing agent: 18.5%–20.0%;

[0013] Anti-mold microcapsules: 7.5%–8.5%;

[0014] Silica powder: 3.5%–5.0%;

[0015] Nano zinc oxide: 2.5%–3.0%;

[0016] Dispersant: 0.3%–0.5%;

[0017] Defoamer: 0.1%–0.3%;

[0018] The remainder is deionized water.

[0019] Furthermore, the anti-mold microcapsules are prepared by the following steps:

[0020] Gelatin and gum arabic were weighed and dissolved separately in deionized water, and stirred in a 50°C water bath until completely dissolved to obtain gelatin solution and gum arabic solution. Berberine and benzimidazole carbamate were weighed and mixed and dissolved in anhydrous ethanol, and ultrasonically dispersed for 5 min to obtain core material solution. The core material solution was added dropwise to the gelatin solution and emulsified at 5000 r / min for 10-20 min to form an O / W emulsion. Then, gum arabic solution was added and stirred for another 10-20 min. After that, the pH of the system was adjusted to 4.0-4.2 with glacial acetic acid. After adjustment, the system was stirred at 40-45°C for 1 h. Then, 10% glutaraldehyde solution was added and stirred for another 2 h. After that, the system was cooled to room temperature, centrifuged to collect microcapsules, washed three times with deionized water, and then vacuum dried at 40°C for 24 h to obtain antifungal microcapsules.

[0021] Furthermore, the ratio of the amount of gelatin, gum arabic, deionized water, berberine, benzimidazole carbamate, anhydrous ethanol, and 10% glutaraldehyde solution is 50g:50g:1L:20g:20g:200mL:40-50mL.

[0022] Furthermore, the modified aqueous epoxy emulsion is prepared by the following steps:

[0023] Hyperbranched epoxy resin and epoxy emulsifier are added to the epoxy resin. After the addition is complete, the system is heated to 40-50°C and stirred at a constant temperature for 1-2 hours. After that, deionized water is added dropwise to the system. At this time, the system is in an oil-in-water state. Continue to add deionized water until the phase inversion occurs, that is, the system is in a water-in-oil state. After that, cool to room temperature and stir at room temperature for 2-4 hours. Then, add deionized water while stirring until the solid content of the system is 55%-60%. Stir at room temperature for 20-30 minutes to obtain the modified waterborne epoxy emulsion.

[0024] Furthermore, the epoxy resin is of type E-51; the epoxy emulsifier is of type WL92.

[0025] Furthermore, the ratio of epoxy resin, hyperbranched epoxy resin, and epoxy emulsifier is 85-90g:10-15g:10-15g.

[0026] Furthermore, the hyperbranched epoxy resin is prepared by the following steps:

[0027] Ethylene glycol diglycidyl ether and tetrabutylammonium bromide were added to the reactor. After this, nitrogen gas was introduced into the reactor, and the temperature was raised to 130–135°C. The reactor was stirred at this temperature for 10–20 minutes. After this, the temperature was lowered to 100–110°C, and trimethylolpropane was added to the reactor while stirring. The addition rate of trimethylolpropane was controlled to ensure that the addition was completed within 2 hours. The temperature was raised to 160–170°C, and the reactor was stirred at this temperature until the epoxy value of the system dropped to 0.2 mol / 100g. After this, the reactor was cooled to room temperature, and the product was collected to obtain hyperbranched epoxy resin.

[0028] Furthermore, the ratio of ethylene glycol diglycidyl ether to tetrabutylammonium bromide in trimethylolpropane is 1 mol: 0.05 mol: 0.4 mol.

[0029] Furthermore, the preparation method of the anti-mildew and anti-corrosion water-based epoxy floor paint includes the following steps:

[0030] Weigh each raw material according to the mass percentage, and take the modified waterborne epoxy emulsion as component A; then stir and mix the waterborne epoxy curing agent, anti-mildew microcapsules, silica powder, nano zinc oxide, dispersant, defoamer and deionized water for 20 to 30 minutes to obtain component B; mix component A and component B, and continue stirring and mixing for 20 to 30 minutes to obtain anti-mildew and anti-corrosion waterborne epoxy floor paint.

[0031] Furthermore, the water-based epoxy curing agent is Anquamine701; the silica powder has a mesh size of 600 mesh; the nano zinc oxide has a particle size of 50 nm; the dispersant is BYK-190; and the defoamer is TEGO Foamex 810.

[0032] The beneficial effects of this invention are:

[0033] This invention addresses three major technical problems of existing waterborne epoxy floor coatings: poor compatibility of antifungal agents, insufficient long-term effectiveness, and decreased mechanical properties of the coating. Through material design and process improvements, it provides a waterborne epoxy floor coating that combines long-lasting antifungal and anti-corrosion properties, high mechanical performance, and environmental friendliness. Based on test data, the beneficial effects of this invention are specifically reflected in the following aspects:

[0034] I. Significantly improved anti-mildew and anti-corrosion performance:

[0035] (1) Synergistic anti-mold mechanism:

[0036] This invention utilizes a complex coagulation method to prepare antifungal microcapsules that encapsulate the natural antifungal agent berberine with the chemical antifungal agent benzimidazole carbamate, forming a broad-spectrum antibacterial synergistic effect. As the test data shows, Examples 10-12 all achieved an antifungal level of 0 (no mold growth), while Comparative Example 5 (direct addition of unencapsulated antifungal agent) achieved level 2 (few colonies), and Comparative Example 7 (single antifungal agent) achieved level 3 (significant colonies). Microencapsulation technology extends the sustained-release period of the antifungal agent, solving the problem of insufficient long-term effectiveness caused by rapid migration or degradation of traditional antifungal agents.

[0037] (2) Enhanced corrosion resistance:

[0038] The nano-zinc oxide (50 nm) and silicon micropowder (600 mesh) of this invention synergistically enhance the coating density, resulting in a salt spray corrosion spread width of only 0.1–0.5 mm (Examples 10–12), significantly better than Comparative Example 4 (spread width 1.2–1.5 mm). The three-dimensional cross-linked network of hyperbranched epoxy resin (Example 5) effectively isolates moisture penetration, while Comparative Example 4, lacking hyperbranching modification, exhibits a significant decrease in corrosion resistance.

[0039] II. Comprehensive optimization of mechanical properties:

[0040] (1) Improved adhesion and abrasion resistance:

[0041] The introduction of the hyperbranched epoxy resins prepared in this invention (Examples 1-3) significantly improved the film-forming properties and crosslinking density of the emulsions. Example 11 achieved an adhesion strength of 5B (no peeling), while Comparative Example 4 (unmodified emulsion) only achieved 3B. In the Taber abrasion test, Example 12 showed an abrasion loss of only 12-15 mg, a 65% reduction compared to Comparative Example 4 (35-40 mg). The hyperbranched structure enhanced the coating's shear resistance through a mechanical chaining effect.

[0042] (2) Breakthrough improvement in water resistance:

[0043] The reverse emulsification process of the modified waterborne epoxy emulsion of the present invention (Examples 4-6) stabilizes the solid content at 55%-60%. Combined with the hydrophobic effect of nano zinc oxide, Examples 10-12 showed no bubbling or peeling after 240h immersion in water, while Comparative Example 6 (insufficient microcapsule cross-linking) showed local peeling, and Comparative Example 7 (single antifungal agent) failed over a large area due to poor interfacial compatibility.

[0044] III. Environmental friendliness:

[0045] This invention utilizes modified waterborne epoxy emulsion to replace the traditional solvent-based system, and combines microencapsulation technology to reduce the volatilization of antifungal agents, thus meeting the environmental protection requirements of the medical and food industries for cleanroom flooring.

[0046] Conclusion: This invention, through the synergistic effect of three technologies—modification of hyperbranched epoxy emulsion, microencapsulation of dual antifungal agents, and nanocomposite reinforcement—completely overcomes the technical bottleneck of existing waterborne epoxy floor coatings that struggle to simultaneously achieve both antifungal and mechanical properties. Example data confirms that its core indicators, such as antifungal rating, salt spray corrosion resistance, and adhesion, all reach industry-leading levels, while also possessing environmental advantages, providing an innovative solution for the high-end cleanroom flooring sector. Detailed Implementation

[0047] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise specified, the raw materials, reagents or devices used in the following embodiments can be obtained from conventional commercial channels or by existing known methods.

[0048] Example 1

[0049] Preparation of hyperbranched epoxy resin:

[0050] 1 mol of ethylene glycol diglycidyl ether (analytical grade) and 0.05 mol of tetrabutylammonium bromide (analytical grade) were added to the reactor. After this, nitrogen gas was introduced into the reactor, and the temperature was raised to 130°C and stirred at a constant temperature for 10 min. After this, the temperature was lowered to 100°C, and 0.4 mol of trimethylolpropane (analytical grade) was added to the reactor while stirring. The addition rate of trimethylolpropane was controlled to ensure that it was added within 2 h. The temperature was raised to 160°C and stirred at a constant temperature until the epoxy value of the system dropped to 0.2 mol / 100 g. After this, the reactor was cooled to room temperature, and the product was collected to obtain hyperbranched epoxy resin.

[0051] Example 2

[0052] Preparation of hyperbranched epoxy resin:

[0053] 1 mol of ethylene glycol diglycidyl ether (analytical grade) and 0.05 mol of tetrabutylammonium bromide (analytical grade) were added to the reactor. After this, nitrogen gas was introduced into the reactor, and the temperature was raised to 130°C and stirred at a constant temperature for 20 min. After this, the temperature was lowered to 105°C, and 0.4 mol of trimethylolpropane (analytical grade) was added to the reactor while stirring. The addition rate of trimethylolpropane was controlled to ensure that it was added within 2 h. The temperature was raised to 165°C and stirred at a constant temperature until the epoxy value of the system dropped to 0.2 mol / 100 g. After this, the reactor was cooled to room temperature, and the product was collected to obtain hyperbranched epoxy resin.

[0054] Example 3

[0055] Preparation of hyperbranched epoxy resin:

[0056] 1 mol of ethylene glycol diglycidyl ether (analytical grade) and 0.05 mol of tetrabutylammonium bromide (analytical grade) were added to the reactor. After this, nitrogen gas was introduced into the reactor, and the temperature was raised to 135°C and stirred at a constant temperature for 20 min. After this, the temperature was lowered to 110°C, and 0.4 mol of trimethylolpropane (analytical grade) was added to the reactor while stirring. The addition rate of trimethylolpropane was controlled to ensure that it was added within 2 h. The temperature was raised to 170°C and stirred at a constant temperature until the epoxy value of the system dropped to 0.2 mol / 100 g. After this, the reactor was cooled to room temperature, and the product was collected to obtain hyperbranched epoxy resin.

[0057] Example 4

[0058] Preparation of modified waterborne epoxy emulsion:

[0059] Add 10g of the hyperbranched epoxy resin prepared in Example 1 and 15g of epoxy emulsifier (WL92) to 85g of epoxy resin (E-51). After the addition is complete, heat the system to 40°C and stir at a constant temperature for 1 hour. After that, add deionized water dropwise to the system. At this time, the system is in an oil-in-water state. Continue to add deionized water dropwise until the phase inversion occurs in the system, that is, the system is in a water-in-oil state. After that, cool to room temperature and stir at room temperature for 2 hours. Then add deionized water dropwise until the solid content of the system is 55%. Stir at room temperature for 20 minutes to obtain the modified waterborne epoxy emulsion.

[0060] Example 5

[0061] Preparation of modified waterborne epoxy emulsion:

[0062] 12g of the hyperbranched epoxy resin prepared in Example 2 and 20g of epoxy emulsifier (WL92) were added to 88g of epoxy resin (E-51). After the addition was complete, the system was heated to 45°C and stirred at a constant temperature for 2 hours. After that, deionized water was added dropwise to the system. At this time, the system was in an oil-in-water state. The addition of deionized water continued until the phase inversion occurred in the system, that is, the system was in a water-in-oil state. After that, the system was cooled to room temperature and stirred at room temperature for 3 hours. Then, deionized water was added and stirred until the solid content of the system was 58%. The system was stirred at room temperature for 30 minutes to obtain the modified waterborne epoxy emulsion.

[0063] Example 6

[0064] Preparation of modified waterborne epoxy emulsion:

[0065] Add 15g of the hyperbranched epoxy resin prepared in Example 3 and 20g of epoxy emulsifier (WL92) to 90g of epoxy resin (E-51). After the addition is complete, heat the system to 50°C and stir at a constant temperature for 2 hours. After that, add deionized water dropwise to the system. At this time, the system is in an oil-in-water state. Continue to add deionized water dropwise until the phase inversion occurs in the system, that is, the system is in a water-in-oil state. After that, cool to room temperature and stir at room temperature for 4 hours. Then add deionized water dropwise until the solid content of the system is 60%. Stir at room temperature for 30 minutes to obtain the modified waterborne epoxy emulsion.

[0066] Comparative Example 1

[0067] Comparative Example 1 served as the control group for Example 5. The raw material “12g of hyperbranched epoxy resin prepared in Example 2” in Example 5 was replaced with “12g of epoxy resin (E-51)”, that is, no hyperbranched epoxy resin was added. The remaining raw materials, raw material amounts and preparation steps remained consistent with those in Example 5, and a modified waterborne epoxy emulsion was finally obtained.

[0068] Example 7

[0069] Preparation of antifungal microcapsules:

[0070] A1. Weigh 50g of gelatin (food grade) and 50g of gum arabic (food grade) and dissolve them separately in 1L of deionized water. Stir in a 50℃ water bath until completely dissolved to obtain gelatin solution and gum arabic solution.

[0071] A2. Weigh 20g of berberine (purity ≥98%) and 20g of benzimidazole carbamate (purity ≥95%), mix them, dissolve them in 200mL of anhydrous ethanol, and ultrasonically disperse for 5min to obtain the core material solution.

[0072] A3. The core material solution was added dropwise to the gelatin solution, and high-speed shear emulsification was carried out at 5000 r / min for 10 min to form an O / W (oil / water) emulsion. Then, gum arabic solution was added and stirring was continued for 10 min to ensure thorough mixing of the wall material. After that, the pH of the system was adjusted to 4.0 with glacial acetic acid. At this time, the gelatin and gum arabic underwent re-aggregation due to charge neutralization, which encapsulated the core material to form microcapsule prototypes. After adjustment, the system was stirred at 40℃ for 1 h to allow the capsule wall to gradually solidify. Then, 40 mL of 10% glutaraldehyde solution (crosslinking agent) was added and stirred for 2 h to enhance the mechanical strength of the microcapsule wall. After completion, the system was cooled to room temperature and centrifuged (3000 r / min, 10 min) to collect the microcapsules. The microcapsules were washed three times with deionized water to remove unencapsulated core material and free wall material, and then placed in a vacuum dryer at 40℃ for 24 h to obtain white powdery anti-mildew microcapsules.

[0073] Example 8

[0074] Preparation of antifungal microcapsules:

[0075] A1. Weigh 50g of gelatin (food grade) and 50g of gum arabic (food grade) and dissolve them separately in 1L of deionized water. Stir in a 50℃ water bath until completely dissolved to obtain gelatin solution and gum arabic solution.

[0076] A2. Weigh 20g of berberine (purity ≥98%) and 20g of benzimidazole carbamate (purity ≥95%), mix them, dissolve them in 200mL of anhydrous ethanol, and ultrasonically disperse for 5min to obtain the core material solution.

[0077] A3. The core material solution was added dropwise to the gelatin solution, and high-speed shear emulsification was carried out at 5000 r / min for 20 min to form an O / W (oil / water) emulsion. Then, gum arabic solution was added and stirring was continued for 20 min to ensure thorough mixing of the wall material. After that, the pH of the system was adjusted to 4.0 with glacial acetic acid. At this time, the gelatin and gum arabic underwent re-aggregation due to charge neutralization, which encapsulated the core material to form microcapsule prototypes. After adjustment, the system was stirred at 45℃ for 1 h to allow the capsule wall to gradually solidify. Then, 45 mL of 10% glutaraldehyde solution (crosslinking agent) was added and stirred for 2 h to enhance the mechanical strength of the microcapsule wall. After that, the system was cooled to room temperature and centrifuged (3000 r / min, 10 min) to collect the microcapsules. The microcapsules were washed three times with deionized water to remove unencapsulated core material and free wall material, and then placed in a vacuum dryer at 40℃ for 24 h to obtain white powdery anti-mildew microcapsules.

[0078] Example 9

[0079] Preparation of antifungal microcapsules:

[0080] A1. Weigh 50g of gelatin (food grade) and 50g of gum arabic (food grade) and dissolve them separately in 1L of deionized water. Stir in a 50℃ water bath until completely dissolved to obtain gelatin solution and gum arabic solution.

[0081] A2. Weigh 20g of berberine (purity ≥98%) and 20g of benzimidazole carbamate (purity ≥95%), mix them, dissolve them in 200mL of anhydrous ethanol, and ultrasonically disperse for 5min to obtain the core material solution.

[0082] A3. The core material solution was added dropwise to the gelatin solution, and high-speed shear emulsification was carried out at 5000 r / min for 20 min to form an O / W (oil / water) emulsion. Then, gum arabic solution was added and stirring was continued for 20 min to ensure thorough mixing of the wall material. After that, the pH of the system was adjusted to 4.2 with glacial acetic acid. At this point, the gelatin and gum arabic underwent re-aggregation due to charge neutralization, encapsulating the core material to form microcapsule prototypes. After adjustment, the system was stirred at 45℃ for 1 h to allow the capsule walls to gradually solidify. Then, 50 mL of 10% glutaraldehyde solution (crosslinking agent) was added and stirred for 2 h to enhance the mechanical strength of the microcapsule walls. After that, the system was cooled to room temperature and centrifuged (3000 r / min, 10 min) to collect the microcapsules. The microcapsules were washed three times with deionized water to remove unencapsulated core material and free wall material, and then vacuum dried at 40℃ for 24 h to obtain white powdery anti-mildew microcapsules.

[0083] Comparative Example 2

[0084] Comparative Example 2 served as the control group for Example 8. The amount of the raw material "45 mL of 10% glutaraldehyde solution (crosslinking agent)" in Example 8 was modified to "25 mL". The remaining raw materials, raw material amounts, and preparation steps remained consistent with those in Example 8, and anti-mold microcapsules were finally obtained.

[0085] Comparative Example 3

[0086] Comparative Example 3 served as the control group for Example 8. The raw material "20g of berberine (purity ≥98%)" in Example 8 was replaced with "20g of benzimidazole carbamate (purity ≥95%)", i.e., a single antifungal agent was used. The remaining raw materials, raw material amounts, and preparation steps remained consistent with those in Example 8, and antifungal microcapsules were finally obtained.

[0087] Example 10

[0088] Preparation of anti-mildew and anti-corrosion water-based epoxy floor coating:

[0089] First, the above-mentioned floor paint includes the following raw materials by weight percentage:

[0090] The modified aqueous epoxy emulsion prepared in Example 4: 45.5%;

[0091] Waterborne epoxy curing agent (Anquamine 701): 18.5%;

[0092] Antifungal microcapsules prepared in Example 7: 7.5%;

[0093] Silica powder (600 mesh): 3.5%;

[0094] Nano zinc oxide (50nm): 2.5%;

[0095] Dispersant (BYK-190): 0.3%;

[0096] Defoamer (TEGO Foamex 810): 0.1%;

[0097] The remainder is deionized water.

[0098] Then, the above-mentioned method for preparing floor coatings includes the following steps:

[0099] Weigh each raw material according to the mass percentage, and take the modified waterborne epoxy emulsion prepared in Example 4 as component A; then stir and mix the waterborne epoxy curing agent, the anti-mildew microcapsules prepared in Example 7, the silica powder, the nano zinc oxide, the dispersant, the defoamer and deionized water for 20 minutes to obtain component B; mix component A and component B, and continue stirring and mixing for 20 minutes to obtain the anti-mildew and anti-corrosion waterborne epoxy floor paint.

[0100] Example 11

[0101] Preparation of anti-mildew and anti-corrosion water-based epoxy floor coating:

[0102] First, the above-mentioned floor paint includes the following raw materials by weight percentage:

[0103] Modified aqueous epoxy emulsion prepared in Example 5: 50%;

[0104] Waterborne epoxy curing agent (Anquamine 701): 20%;

[0105] Antifungal microcapsules prepared in Example 8: 8%;

[0106] Silica powder (600 mesh): 4%;

[0107] Nano zinc oxide (50nm): 3.0%;

[0108] Dispersant (BYK-190): 0.5%;

[0109] Defoamer (TEGO Foamex 810): 0.2%;

[0110] The remainder is deionized water.

[0111] Then, the above-mentioned method for preparing floor coatings includes the following steps:

[0112] Weigh each raw material according to the mass percentage, and take the modified waterborne epoxy emulsion prepared in Example 5 as component A; then stir and mix the waterborne epoxy curing agent, the anti-mildew microcapsules prepared in Example 8, the silica powder, the nano zinc oxide, the dispersant, the defoamer and deionized water for 30 min to obtain component B; mix component A and component B, and continue stirring and mixing for 30 min to obtain the anti-mildew and anti-corrosion waterborne epoxy floor paint.

[0113] Example 12

[0114] Preparation of anti-mildew and anti-corrosion water-based epoxy floor coating:

[0115] First, the above-mentioned floor paint includes the following raw materials by weight percentage:

[0116] The modified aqueous epoxy emulsion prepared in Example 6: 52.0%;

[0117] Waterborne epoxy curing agent (Anquamine 701): 20.0%;

[0118] Antifungal microcapsules prepared in Example 9: 8.5%;

[0119] Silica powder (600 mesh): 5.0%;

[0120] Nano zinc oxide (50nm): 3.0%;

[0121] Dispersant (BYK-190): 0.5%;

[0122] Defoamer (TEGO Foamex 810): 0.3%;

[0123] The remainder is deionized water.

[0124] Then, the above-mentioned method for preparing floor coatings includes the following steps:

[0125] Weigh each raw material according to the mass percentage, and take the modified waterborne epoxy emulsion prepared in Example 6 as component A; then stir and mix the waterborne epoxy curing agent, the anti-mildew microcapsules prepared in Example 9, the silica powder, the nano zinc oxide, the dispersant, the defoamer and deionized water for 30 min to obtain component B; mix component A and component B, and continue to stir and mix for 30 min to obtain the anti-mildew and anti-corrosion waterborne epoxy floor paint.

[0126] Comparative Example 4

[0127] Comparative Example 4 served as the control group for Example 11. The raw material "modified waterborne epoxy emulsion prepared in Example 5" in Example 11 was replaced with "modified waterborne epoxy emulsion prepared in Comparative Example 1". The remaining raw materials, raw material amounts, and preparation steps remained consistent with those in Example 11, and finally, anti-mildew and anti-corrosion waterborne epoxy floor paint was obtained.

[0128] Comparative Example 5

[0129] Comparative Example 5 was the control group of Example 11. The raw material "anti-mildew microcapsules prepared in Example 8" in Example 11 was replaced with "berberine and benzimidazole carbamate in equal mass ratio", that is, the microcapsule structure was removed. The remaining raw materials, raw material amounts and preparation steps were kept consistent with those in Example 11, and finally anti-mildew and anti-corrosion waterborne epoxy floor paint was obtained.

[0130] Comparative Example 6

[0131] Comparative Example 6 served as the control group for Example 11. The raw material "anti-mildew microcapsules prepared in Example 8" in Example 11 was replaced with "anti-mildew microcapsules prepared in Comparative Example 2", that is, the microcapsule structure was removed. The remaining raw materials, raw material amounts, and preparation steps remained consistent with those in Example 11, and finally, anti-mildew and anti-corrosion waterborne epoxy floor paint was obtained.

[0132] Comparative Example 7

[0133] Comparative Example 7 served as the control group for Example 11. The raw material "anti-mildew microcapsules prepared in Example 8" in Example 11 was replaced with "anti-mildew microcapsules prepared in Comparative Example 3", that is, the microcapsule structure was removed. The remaining raw materials, raw material amounts, and preparation steps remained consistent with those in Example 11, and finally, anti-mildew and anti-corrosion waterborne epoxy floor paint was obtained.

[0134] Test Example 1

[0135] The anti-mildew and anti-corrosion water-based epoxy floor coatings prepared in Examples 10-12 and Comparative Examples 4-7 were respectively coated on the surface of a 50cm×50cm flat plate and dried at room temperature for 24 hours to form 2mm paint samples. The paint samples were then subjected to performance tests. The performance test process is as follows, and the test results are shown in Table 1:

[0136] (1) Anti-mildew grade (GB / T 1741-2020): The paint sample was inoculated with five kinds of molds, including Aspergillus niger, and cultured at 28℃ / 95%RH for 28 days. The samples were evaluated according to grades 0 to 4 (grade 0: no growth; grade 4: full coverage).

[0137] (2) Salt spray corrosion resistance (ASTM B117): Scratched paint samples were exposed to a 5% NaCl fog chamber, and the rust expansion width (mm) was recorded after 720 hours.

[0138] (3) Adhesion (GB / T 9286-2021): Cross-cut test (1mm spacing), observe the area of ​​paint peeling off the surface after the tape is peeled off (0~5B, 5B is the best).

[0139] (4) Abrasion resistance (GB / T 1768-2006): Taber abrasion tester (500g / wheel, 1000 rpm), mass loss (mg).

[0140] (5) Water resistance (GB / T 1733-1993): After immersion in water for 240 hours, observe the blistering and peeling of the paint sample.

[0141] Table 1 Test Results

[0142]

[0143] It should be noted that, in this document, terms such as “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0144] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A mildew- and corrosion-resistant water-based epoxy floor coating, characterized in that, Including the following percentages of raw materials by weight: Modified waterborne epoxy emulsion: 45.5%–52.0%; Water-based epoxy curing agent: 18.5%~20.0%; Anti-mold microcapsules: 7.5%–8.5%; Silica powder: 3.5%–5.0%; Nano zinc oxide: 2.5%–3.0%; Dispersant: 0.3%–0.5%; Defoamer: 0.1%–0.3%; The remainder is deionized water; The anti-mold microcapsules are prepared by the following steps: Gelatin and gum arabic were weighed and dissolved separately in deionized water, and stirred in a 50°C water bath until completely dissolved to obtain gelatin solution and gum arabic solution. Berberine and benzimidazole carbamate were weighed and mixed and dissolved in anhydrous ethanol, and ultrasonically dispersed for 5 min to obtain core material solution. The core material solution was added dropwise to the gelatin solution and emulsified at 5000 r / min for 10-20 min to form an O / W emulsion. Then, gum arabic solution was added and stirred for another 10-20 min. After that, the pH of the system was adjusted to 4.0-4.2 with glacial acetic acid. After adjustment, the system was stirred at 40-45°C for 1 h. Then, 10% glutaraldehyde solution was added and stirred for another 2 h. After that, the system was cooled to room temperature, centrifuged to collect microcapsules, washed three times with deionized water, and then vacuum dried at 40°C for 24 h to obtain anti-mold microcapsules. The modified aqueous epoxy emulsion is prepared by the following steps: Hyperbranched epoxy resin and epoxy emulsifier are added to epoxy resin. After the addition is complete, the system is heated to 40-50℃ and stirred at a constant temperature for 1-2 hours. After that, deionized water is added dropwise to the system. At this time, the system is in an oil-in-water state. Continue to add deionized water until the phase inversion occurs in the system, that is, the system is in a water-in-oil state. After that, cool to room temperature and stir at room temperature for 2-4 hours. Then add deionized water while stirring until the solid content of the system is 55%-60%. Stir at room temperature for 20-30 minutes to obtain the modified waterborne epoxy emulsion. The hyperbranched epoxy resin is prepared by the following steps: Ethylene glycol diglycidyl ether and tetrabutylammonium bromide were added to the reactor. After this, nitrogen gas was introduced into the reactor, and the temperature was raised to 130–135°C. The reactor was stirred at this temperature for 10–20 minutes. After this, the temperature was lowered to 100–110°C, and trimethylolpropane was added to the reactor while stirring. The addition rate of trimethylolpropane was controlled to ensure that the addition was completed within 2 hours. The temperature was raised to 160–170°C, and the reactor was stirred at this temperature until the epoxy value of the system dropped to 0.2 mol / 100g. After this, the reactor was cooled to room temperature, and the product was collected to obtain hyperbranched epoxy resin.

2. The anti-mildew and anti-corrosion water-based epoxy floor coating according to claim 1, characterized in that, The ratio of the amounts of gelatin, gum arabic, deionized water, berberine, benzimidazole carbamate, anhydrous ethanol, and 10% glutaraldehyde solution is 50g:50g:1L:20g:20g:200mL:40-50mL.

3. The anti-mildew and anti-corrosion water-based epoxy floor coating according to claim 1, characterized in that, The ratio of epoxy resin, hyperbranched epoxy resin, and epoxy emulsifier is 85-90g:10-15g:10-15g.

4. The anti-mildew and anti-corrosion water-based epoxy floor coating according to claim 1, characterized in that, The ratio of ethylene glycol diglycidyl ether to tetrabutylammonium bromide in trimethylolpropane is 1 mol: 0.05 mol: 0.4 mol.

5. A method for preparing a mildew-proof and corrosion-resistant water-based epoxy floor coating according to any one of claims 1 to 4, characterized in that, Includes the following steps: Weigh each raw material according to the mass percentage, and take the modified waterborne epoxy emulsion as component A; then stir and mix the waterborne epoxy curing agent, anti-mildew microcapsules, silica powder, nano zinc oxide, dispersant, defoamer and deionized water for 20 to 30 minutes to obtain component B; mix component A and component B, and continue stirring and mixing for 20 to 30 minutes to obtain anti-mildew and anti-corrosion waterborne epoxy floor paint.

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