Antibacterial epoxy resin coating and preparation process thereof
By introducing quaternary ammonium salts and isothiazolinone antibacterial groups into epoxy resin to form an oxazolidinone structure, the problems of microbial growth and silver ion precipitation in epoxy resin coatings are solved, resulting in a highly efficient antibacterial and heat-resistant coating suitable for high-cleanliness environments such as hospitals.
Patent Information
- Application Number
- CN202610970960.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-01
- Publication Date
- 2026-08-25
AI Technical Summary
Traditional epoxy resin coatings are prone to becoming a breeding ground for microorganisms in humid or warm environments, leading to performance degradation and hygiene and safety hazards. Existing silver ion-based antibacterial agents are expensive and prone to precipitation, affecting coating performance and safety.
An oxazolidinone structure is formed by chemically grafting epoxy resin with two antibacterial groups: quaternary ammonium salt and isothiazolinone. This structure achieves broad-spectrum antibacterial activity through electrostatic interaction and cell membrane disruption, while avoiding the release of heavy metals.
It significantly improves antibacterial and heat resistance, has strong coating stability, is suitable for high-cleanliness environments, and avoids the risk of heavy metal residue.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of epoxy resin coating technology, specifically, it relates to an antibacterial epoxy resin coating and its preparation process. Background Technology
[0002] With the significant improvement in public health awareness and the increasingly stringent requirements for the hygienic performance of materials across various industries, the research and development of antibacterial functional materials has become one of the hot topics in the field of materials science. Epoxy resin coatings, due to their excellent adhesion, mechanical strength, chemical corrosion resistance, and electrical insulation properties, are widely used in many key fields such as construction, electronics, aerospace, medical devices, food processing, and marine engineering.
[0003] However, traditional epoxy resin coatings have a significant drawback in practical applications: their surfaces easily become breeding grounds for microorganisms (such as bacteria and mold) to attach and multiply in humid or warm environments. The proliferation of microorganisms on the coating surface not only leads to the deterioration of the material's properties, such as stains, odors, and biocorrosion, but may also spread pathogens through contact, posing a potential threat to public health and safety, especially in places like hospitals where hygiene requirements are extremely high.
[0004] To overcome this deficiency, the industry typically uses antibacterial additives in epoxy resin systems to impart antibacterial properties to coatings. Currently, most antibacterial epoxy coatings use silver ion-based agents. While silver-based antibacterial agents offer advantages such as broad-spectrum antibacterial activity and good heat resistance, they are expensive and prone to aggregation and precipitation in epoxy systems. This results in limited antibacterial efficacy and potential environmental impacts. Furthermore, they affect the smoothness, transparency, and mechanical properties of the coating, cause rapid decay of the antibacterial effect, and pose a risk of heavy metal residue with long-term use.
[0005] Against this backdrop, there is an urgent need to invent an antibacterial epoxy resin coating for use in the wall and floor coating of medical facilities, especially operating rooms, intensive care units and wards, which have extremely high requirements for environmental cleanliness. Summary of the Invention
[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide an antibacterial epoxy resin coating and its preparation process.
[0007] The objective of this invention can be achieved through the following technical solutions: An antibacterial epoxy resin coating comprising component A and component B.
[0008] As a further technical solution, the mass ratio of component A to component B is 4-5:1.
[0009] As a further technical solution, component B is an alicyclic amine curing agent.
[0010] As a further technical solution, component A comprises the following raw materials in parts by weight: 70-90 parts antibacterial epoxy resin, 10-15 parts reactive diluent, 15-25 parts filler, 0.5-1.5 parts dispersant, 0.2-0.4 parts defoamer, and 0.5-1 part rheology modifier.
[0011] As a further technical solution, the filler is a mixture of titanium dioxide and talc powder, with a mass ratio of 1:1.
[0012] As a further technical solution, the rheology modifier is fumed silica.
[0013] As a further technical solution, the antibacterial epoxy resin is prepared through the following steps: B1. In a round-bottom flask, add 2-methyl-4-isothiazolin-3-one, 4-bromo-1-butanol and acetonitrile, attach a reflux condenser, turn on magnetic stirring, heat in an oil bath to 70-75℃, keep the reaction at this temperature for 9-12 hours. After the reaction is complete, cool to room temperature and obtain the intermediate product through post-treatment. B2. In a round-bottom flask, add the intermediate product and anhydrous N,N-dimethylformamide, stir well, and then, under nitrogen protection, add hexamethylene diisocyanate and dibutyltin dilaurate dropwise to the flask. After the addition is complete, stir at room temperature for 1-1.5 h, then heat to 40-50℃ and stir for 4-6 h. After the reaction is complete, cool to room temperature and obtain the antibacterial agent through post-treatment. B3. Assemble a stirrer in a three-necked flask, introduce nitrogen gas, add bisphenol A epoxy resin and ethylene glycol diglycidyl ether, stir evenly, then add antibacterial agent and 2-methylimidazole in sequence, then raise the temperature to 140-150℃, reflux the reaction at this temperature for 3-4 hours, after the reaction is completed, stop heating and proceed with post-treatment to obtain antibacterial epoxy resin.
[0014] As a further technical solution, in step B1, the ratio of 2-methyl-4-isothiazolin-3-one to 4-bromo-1-butanol is 11.5g:15.3g.
[0015] As a further technical solution, in step B2, the ratio of the intermediate product, hexamethylene diisocyanate and dibutyltin dilaurate is 18.8g:19.2-20.5g:0.3g.
[0016] As a further technical solution, in step B3, the ratio of bisphenol A epoxy resin, antibacterial agent and 2-methylimidazole is 100g:25.5-29.5g:0.4g.
[0017] In the above preparation process, the reaction formulas for steps B1 and B2 are as follows:
[0018] In the preparation of antibacterial epoxy resin, it is important to ensure that in step B2, the molar ratio of the intermediate product to hexamethylene diisocyanate is close to 1:1, with the latter in excess, so that one isocyanate group is reserved for subsequent reactions.
[0019] This invention first prepares an antibacterial agent and then uses it to modify epoxy resin. The antibacterial agent molecule contains two antibacterial components: a quaternary ammonium salt and an isothiazolinone. The quaternary ammonium salt is a cationic antibacterial group; the positively charged quaternary ammonium ions can actively adsorb negatively charged bacterial cells, disrupting the cell wall and cell membrane structure through electrostatic interaction, leading to the leakage of intracellular substances and achieving sterilization. Meanwhile, the isothiazolinone can inhibit bacterial and fungal metabolism and reproduction by disrupting the permeability of bacterial and fungal cell membranes, breaking the DNA and RNA chains inside the cells. The inhibitory effect on fungi is particularly outstanding, making up for the relatively weak antifungal ability of quaternary ammonium salts; the two work synergistically to significantly improve the antibacterial properties of the matrix; in addition, the isocyanate group in the antibacterial agent molecule reacts with the epoxy group in the epoxy resin to form an oxazolidinone structure, which has good heat resistance and improves the heat resistance of the matrix to a certain extent; finally, compared with physically blended antibacterial epoxy resins, this grafted modified product has no risk of antibacterial agent migration and precipitation, and is not only highly stable, but also safer for the environment and human body.
[0020] This invention also provides a preparation process for an antibacterial epoxy resin coating, comprising the following steps: A1. In a stainless steel dispersion vessel, add antibacterial epoxy resin and reactive diluent in sequence, turn on low speed stirring to mix them thoroughly and evenly, then slowly add dispersant, defoamer and filler. After the feeding is completed, increase the speed of the disperser and disperse at high speed for 20-30 minutes, then slowly add rheology modifier, and continue stirring for 10-15 minutes to stabilize the viscosity of the system. After filtration, obtain component A. A2. When using, mix components A and B, and let stand for 15-20 minutes to mature, thus obtaining an antibacterial epoxy resin coating.
[0021] As a further technical solution, the rotation speed of the low-speed stirring is 300-500 rpm.
[0022] As a further technical solution, the high-speed dispersion rotation speed is 1200-1500 rpm.
[0023] As a further technical solution, the mesh size of the filter is 100 mesh or 120 mesh.
[0024] The beneficial effects of this invention are: 1. This invention introduces two antibacterial groups, quaternary ammonium salt and isothiazolinone, into the molecular structure of epoxy resin through chemical synthesis, which significantly improves the antibacterial broad spectrum and efficacy. 2. The oxazolidinone structure generated by the reaction of the prepared antibacterial agent with epoxy resin has good heat resistance, which helps to improve the thermal stability of the coating; 3. Through the reasonable combination of components such as reactive diluents and rheology modifiers, the coating has suitable viscosity, good thixotropy and anti-sagging properties; 4. It avoids the use of heavy metal antibacterial agents such as silver ions, reducing the risk of heavy metal residues. In addition, the antibacterial agents are bound by chemical bonds and will not precipitate, making it environmentally friendly. In summary, the coating prepared by this invention has excellent antibacterial properties and certain heat resistance, and is suitable for places with extremely high cleanliness requirements, such as hospital operating rooms and intensive care units. Detailed Implementation
[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.
[0026] Example 1 Preparation of antibacterial epoxy resin: B1. In a round-bottom flask, add 11.5 g of 2-methyl-4-isothiazolin-3-one, 4-bromo-1-butanol and 100 mL of acetonitrile, attach a reflux condenser, turn on magnetic stirring, heat in an oil bath to 70 °C, and keep the reaction at this temperature for 9 h. After the reaction is complete, cool to room temperature, remove the acetonitrile by rotary evaporation, add acetone, grind, filter, wash with acetone, dry to obtain crude product, recrystallize with ethanol-diethyl ether to obtain intermediate product; B2. In a round-bottom flask, add 18.8 g of the intermediate product and 120 mL of anhydrous N,N-dimethylformamide. After stirring evenly, under nitrogen protection, add 19.2 g of hexamethylene diisocyanate and 0.3 g of dibutyltin dilaurate dropwise to the flask. After the addition is complete, stir at room temperature for 1 h, then heat to 40 °C and stir for 4 h. After the reaction is complete, cool to room temperature, pour the reaction solution into petroleum ether to precipitate, filter, wash with diethyl ether, and vacuum dry to obtain the antibacterial agent. B3. Assemble a stirrer in a three-necked flask, introduce nitrogen gas, add 100g of bisphenol A epoxy resin (E-51) and 200mL of ethylene glycol diglycidyl ether, stir evenly, then add 25.5g of antibacterial agent and 0.4g of 2-methylimidazole in sequence, then raise the temperature to 140℃, and reflux the reaction for 3 hours at this temperature. After the reaction is completed, stop heating and rotary evaporate under vacuum to obtain antibacterial epoxy resin. A preparation process for an antibacterial epoxy resin coating includes the following steps: A1. In a stainless steel dispersion vessel, add 70 parts of antibacterial epoxy resin and 10 parts of reactive diluent (n-butyl glycidyl ether) in sequence. Turn on low-speed stirring (300 rpm) to mix thoroughly. Then slowly add 0.5 parts of dispersant (BYK-P104), 0.2 parts of defoamer (BYK-066N), and 15 parts of filler (a mixture of titanium dioxide and talc in a 1:1 mass ratio). After the addition is complete, increase the speed of the disperser (1200 rpm) and disperse at high speed for 20 minutes. Then slowly add 0.5 parts of fumed silica and continue stirring for 10 minutes to stabilize the viscosity of the system. After filtering through a 100-mesh filter, obtain component A. A2. When using, mix component A and component B (cycloaliphatic amine curing agent TAC-900) at a mass ratio of 4:1, let stand and mature for 15 minutes to obtain antibacterial epoxy resin coating.
[0027] Example 2 Preparation of antibacterial epoxy resin: B1. In a round-bottom flask, add 11.5 g of 2-methyl-4-isothiazolin-3-one, 4-bromo-1-butanol and 100 mL of acetonitrile, attach a reflux condenser, turn on magnetic stirring, heat in an oil bath to 75 °C, and keep the reaction at this temperature for 12 h. After the reaction is complete, cool to room temperature, remove the acetonitrile by rotary evaporation, add acetone, grind, filter, wash with acetone, dry to obtain crude product, recrystallize with ethanol-diethyl ether to obtain intermediate product; B2. In a round-bottom flask, add 18.8 g of the intermediate product and 120 mL of anhydrous N,N-dimethylformamide. After stirring evenly, under nitrogen protection, add 20.5 g of hexamethylene diisocyanate and 0.3 g of dibutyltin dilaurate dropwise to the flask. After the addition is complete, stir at room temperature for 1.5 h, then heat to 50 °C and stir for 6 h. After the reaction is complete, cool to room temperature, pour the reaction solution into petroleum ether to precipitate, filter, wash with diethyl ether, and vacuum dry to obtain the antibacterial agent. B3. Assemble a stirrer in a three-necked flask, introduce nitrogen gas, add 100g of bisphenol A epoxy resin (E-51) and 200mL of ethylene glycol diglycidyl ether, stir evenly, then add 29.5g of antibacterial agent and 0.4g of 2-methylimidazole in sequence, then raise the temperature to 150℃, and reflux the reaction for 4 hours at this temperature. After the reaction is completed, stop heating and rotary evaporate under vacuum to obtain antibacterial epoxy resin. A preparation process for an antibacterial epoxy resin coating includes the following steps: A1. In a stainless steel dispersion vessel, add 80 parts of antibacterial epoxy resin and 12.5 parts of reactive diluent (n-butyl glycidyl ether) in sequence. Turn on low-speed stirring (500 rpm) to mix thoroughly. Then slowly add 1.0 part of dispersant (BYK-P104), 0.3 parts of defoamer (BYK-066N), and 20 parts of filler (a mixture of titanium dioxide and talc in a 1:1 mass ratio). After the addition is complete, increase the speed of the disperser (1500 rpm) and disperse at high speed for 30 minutes. Then slowly add 0.75 parts of fumed silica and continue stirring for 15 minutes to stabilize the viscosity of the system. After filtering through a 100-mesh filter, obtain component A. A2. When using, mix component A and component B (cycloaliphatic amine curing agent TAC-900) at a mass ratio of 5:1, let stand and mature for 20 minutes to obtain antibacterial epoxy resin coating.
[0028] Example 3 The only difference between this embodiment and Embodiment 2 is that, in this embodiment, the preparation process of an antibacterial epoxy resin coating includes the following steps: A1. In a stainless steel dispersion vessel, add 90 parts of antibacterial epoxy resin and 15 parts of reactive diluent (n-butyl glycidyl ether) in sequence. Turn on low-speed stirring (500 rpm) to mix thoroughly. Then slowly add 1.5 parts of dispersant (BYK-P104), 0.4 parts of defoamer (BYK-066N), and 25 parts of filler (a mixture of titanium dioxide and talc in a 1:1 mass ratio). After the addition is complete, increase the speed of the disperser (1500 rpm) and disperse at high speed for 30 minutes. Then slowly add 1 part of fumed silica and continue stirring for 15 minutes to stabilize the viscosity of the system. After filtering through a 120-mesh filter, obtain component A. A2. When using, mix component A and component B (cycloaliphatic amine curing agent TAC-900) at a mass ratio of 5:1, let stand and mature for 20 minutes to obtain antibacterial epoxy resin coating.
[0029] Comparative Example 1 The only difference between this comparative example and Example 3 is that, in this comparative example, unmodified bisphenol A epoxy resin was used instead of antibacterial epoxy resin to prepare the coating.
[0030] Comparative Example 2 The only difference between this comparative example and Comparative Example 1 is that in this comparative example, 3 parts by weight of 2-methyl-4-isothiazolin-3-one (antibacterial agent) were added to the formulation to obtain the coating.
[0031] The following performance tests were conducted on Examples 1, 2, and 3, and Comparative Examples 1 and 2: The adhesion of the samples was determined according to the national standard GB / T 9286 "Paints and Varnishes - Cross-cut Test Method"; Using the national standard GB / T 1735 "Determination of heat resistance of paints and varnishes", the coated samples were placed in an oven at 200℃ for 2 hours and then removed to observe the changes in the appearance of the paint film. The antibacterial rate was determined according to the national standard GB / T 21866 "Determination of Antiviral Activity and Antibacterial Properties of Coatings", with Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 6538) as the bacterial strains.
[0032] The performance test results are shown in Table 1: Table 1
[0033] As can be seen from the table above, the coatings prepared in the embodiments of the present invention have higher antibacterial and heat resistance than the comparative examples. Therefore, the coatings prepared in the present invention are suitable for places with extremely high cleanliness requirements, such as hospital operating rooms and intensive care units.
[0034] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.
Claims
1. An antibacterial epoxy resin coating, comprising component A and component B, characterized in that, Component A comprises the following raw materials in parts by weight: 70-90 parts antibacterial epoxy resin, 10-15 parts reactive diluent, 15-25 parts filler, 0.5-1.5 parts dispersant, 0.2-0.4 parts defoamer, and 0.5-1 part rheology modifier.
2. The antibacterial epoxy resin coating according to claim 1, characterized in that, The antibacterial epoxy resin is prepared by the following steps: B1. In a flask, add 2-methyl-4-isothiazolin-3-one, 4-bromo-1-butanol and acetonitrile, turn on magnetic stirring, heat in an oil bath to 70-75℃, and keep the reaction at this temperature for 9-12 hours. Once the reaction is complete, the intermediate product is obtained. B2. In a flask, add the intermediate product and anhydrous N,N-dimethylformamide, stir well, and then, under nitrogen protection, add hexamethylene diisocyanate and dibutyltin dilaurate dropwise to the flask. After the addition is complete, stir at room temperature for 1-1.5 h, and then react at 40-50℃ for 4-6 h. Once the reaction is complete, the antibacterial agent is obtained. B3. In a flask, nitrogen gas is introduced, and bisphenol A epoxy resin and ethylene glycol diglycidyl ether are added. After stirring evenly, antibacterial agent and 2-methylimidazole are added in sequence. The mixture is refluxed at 140-150℃ for 3-4 hours. After the reaction is completed, antibacterial epoxy resin is obtained.
3. The antibacterial epoxy resin coating according to claim 2, characterized in that, In step B1, the ratio of 2-methyl-4-isothiazolin-3-one to 4-bromo-1-butanol is 11.5g:15.3g.
4. The antibacterial epoxy resin coating according to claim 2, characterized in that, In step B2, the ratio of the intermediate product, hexamethylene diisocyanate, and dibutyltin dilaurate is 18.8 g: 19.2-20.5 g: 0.3 g.
5. The antibacterial epoxy resin coating according to claim 2, characterized in that, In step B3, the ratio of bisphenol A epoxy resin, antibacterial agent and 2-methylimidazole is 100g:25.5-29.5g:0.4g.
6. The antibacterial epoxy resin coating according to claim 1, characterized in that, The mass ratio of component A to component B is 4-5:
1.
7. The antibacterial epoxy resin coating according to claim 1, characterized in that, Component B is an alicyclic amine curing agent.
8. The antibacterial epoxy resin coating according to claim 1, characterized in that, The filler is a mixture of titanium dioxide and talc in a mass ratio of 1:1; the rheology modifier is fumed silica.
9. A preparation process for an antibacterial epoxy resin coating, used to prepare the antibacterial epoxy resin coating according to any one of claims 1-8, characterized in that, Includes the following steps: A1. In a stainless steel dispersion vessel, add antibacterial epoxy resin and reactive diluent in sequence, turn on low speed stirring to mix them thoroughly and evenly, then add dispersant, defoamer and filler. After the feeding is completed, disperse at high speed for 20-30 minutes, then add rheology modifier, continue stirring for 10-15 minutes, filter to obtain component A. A2. When using, mix components A and B, and let stand for 15-20 minutes to mature, thus obtaining an antibacterial epoxy resin coating.
10. The preparation process of an antibacterial epoxy resin coating according to claim 1, characterized in that, The low-speed stirring speed is 300-500 rpm; the high-speed dispersion speed is 1200-1500 rpm.