Antibacterial coating material for inner wall of pipeline

Abstract

The invention discloses an antibacterial coating material for the inner wall of a pipeline. The antibacterial coating material comprises the following substances: bisphenol A epoxy resin, a composite antibacterial agent, nano silicon dioxide, a defoaming agent, a flatting agent and tetrahydrofuran; wherein a preparation process of the composite antibacterial agent comprises the following steps: mixing glycidyl methacrylate, an antibacterial monomer, beta-mercaptoethanol, azodiisobutyronitrile and tetrahydrofuran, introducing nitrogen for bubbling for 30-40 minutes, then raising the temperature to 60-70 DEG C, reacting for 10-12 hours, cooling to room temperature after the reaction is finished, precipitating a product by using excessive methanol, and performing vacuum drying to obtain the composite antibacterial agent. The composite antibacterial agent has the beneficial effects that the composite antibacterial agent is prepared through free radical polymerization reaction, and the mechanical strength and lasting antibacterial performance of the material are effectively guaranteed through a three-dimensional rigid framework and antibacterial active groups contained in the composite antibacterial agent.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and in particular relates to an antibacterial coating material for the inner wall of a pipeline. Background Art

[0002] In pipeline transportation systems, the inner wall is prone to breeding bacteria, fungi and other microorganisms, forming biofilms, causing corrosion and blockage problems. Traditional pipeline antibacterial technologies mainly include adding chemical bactericides, using antibacterial metals (such as silver and copper) or applying antibacterial coatings. However, these methods have obvious defects: chemical bactericides may cause environmental pollution or drug resistance due to continuous release; antibacterial metals are expensive and are prone to failure due to ion dissolution after long-term use; and the mechanical properties and antibacterial durability of existing antibacterial coatings are often difficult to balance. For example, although some coatings have good antibacterial effects, they are not flexible enough and are prone to cracking and falling off due to pipeline deformation or fluid erosion. In addition, the antibacterial components (such as nanosilver) in conventional coatings are prone to agglomeration or loss, resulting in a decrease in antibacterial performance over time.

[0003] Therefore, in order to solve the above problems, the present invention provides an antibacterial coating material for the inner wall of a pipeline. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide an antibacterial coating material for the inner wall of a pipeline.

[0005] The purpose of the present invention can be achieved through the following technical solutions: An antibacterial coating material for the inner wall of a pipeline comprises the following substances: by weight, 80-100 parts of bisphenol A epoxy resin, 10-20 parts of a composite antibacterial agent, 3-4 parts of nano silicon dioxide, 1-2 parts of a defoaming agent, 1-2 parts of a leveling agent, and 100-120 parts of tetrahydrofuran; Among them, the preparation process of the composite antibacterial agent is: mix glycidyl methacrylate, antibacterial monomer, β-mercaptoethanol, azobisisobutyronitrile, and tetrahydrofuran, bubble nitrogen for 30-40 minutes, then increase the temperature to 60-70°C, react for 10-12 hours, cool to room temperature after the reaction, precipitate the product with excess methanol, and vacuum dry to obtain the composite antibacterial agent.

[0006] In the scheme, glycidyl methacrylate, antibacterial monomer and β-mercaptoethanol are reacted by free radical polymerization under the initiation of azobisisobutyronitrile to prepare a composite antibacterial agent.

[0007] More optimally, the raw materials in the composite antibacterial agent include the following components: by weight, 2-3 parts of glycidyl methacrylate, 15-18 parts of antibacterial monomer, 0.7-0.9 parts of β-mercaptoethanol, 0.1-0.2 parts of azobisisobutyronitrile, and 130-150 parts of tetrahydrofuran.

[0008] Preferably, the preparation process of the antibacterial monomer is as follows: S1: Mix guaiacol, absolute ethanol, concentrated sulfuric acid, N-hydroxymethyl propionamide, and anhydrous magnesium sulfate, stir evenly, react in a water bath at 35 °C for 24 h. After the reaction, filter, wash, and recrystallize to obtain intermediate A; S2: Mix intermediate A, furfurylamine, paraformaldehyde, and absolute ethanol, raise the temperature to 90 - 100 °C, reflux for 4 - 5 h. Then use a rotary evaporator to evaporate the solution, remove ethanol, wash, and dry to obtain intermediate B; S3: Mix 11-bromo-1-undecanol, 1-adamantane carboxylic acid, p-toluenesulfonic acid, and cyclohexane, raise the temperature to 80 - 90 °C, reflux for 10 - 12 h. After the reaction is completed, concentrate the mixture, dissolve the crude product in ethyl acetate, wash, dry, and purify to obtain intermediate C; S4: Add intermediate C and intermediate B to acetonitrile, raise the temperature to 60 - 70 °C, stir and react for 3 - 4 h. After the reaction, cool to room temperature and perform post-treatment to obtain the antibacterial monomer.

[0009] In the scheme, hydroxymethyl acrylamide dehydrates to form a carbocation under acidic conditions. This carbocation attacks the aromatic ring of guaiacol as an electrophilic reagent to obtain intermediate A. The specific synthesis process is as follows: Preferably, the raw materials in intermediate A include the following components: by weight, 12 - 15 parts of guaiacol, 60 - 70 parts of absolute ethanol, 0.4 - 0.5 parts of concentrated sulfuric acid, 10 - 12 parts of N-hydroxymethyl propionamide, and 1 - 2 parts of anhydrous magnesium sulfate.

[0010] In the scheme, the formaldehyde decomposed from paraformaldehyde undergoes a nucleophilic addition reaction with furfurylamine, then dehydrates to form an imine ion. Then, the carbon atom with active hydrogen in intermediate A attacks the carbon atom of the imine ion to obtain intermediate B. The specific synthesis process is as follows: Preferably, the raw materials in intermediate B include the following components: by weight, 12 - 15 parts of intermediate A, 9 - 10 parts of furfurylamine, 3 - 4 parts of paraformaldehyde, and 50 - 60 parts of absolute ethanol.

[0011] In the scheme, the hydroxyl group of 11-bromo-1-undecanol and 1-adamantane carboxylic acid undergo an esterification reaction under the action of p-toluenesulfonic acid (acid catalyst) to obtain intermediate C. The specific synthesis process is as follows: Preferably, the raw materials in the intermediate C include the following components: by weight, 25-28 parts of 11-bromo-1-undecanol, 18-20 parts of 1-adamantanecarboxylic acid, 1-2 parts of p-toluenesulfonic acid, and 15-18 parts of cyclohexane.

[0012] In the scheme, the nucleophilic site of intermediate B attacks the carbon atom with partial positive charge in intermediate C, thereby obtaining the antibacterial monomer, and its structure is as follows: Preferably, the raw materials in the antibacterial monomer include the following components: by weight, 25-28 parts of intermediate C, 12-15 parts of intermediate B, and 40-50 parts of acetonitrile.

[0013] Preferably, the defoamer includes one or more of silicone defoamers, polyether defoamers, and fatty acid ester defoamers; the leveling agent includes one or more of acrylate leveling agents and silicone leveling agents.

[0014] Advantages of the present invention: The present invention prepares the composite antibacterial agent through a free radical polymerization reaction. The three-dimensional rigid skeleton and antibacterial active groups contained therein effectively ensure the mechanical strength and lasting antibacterial performance of the material. Specifically as follows: First: In the scheme, the three-dimensional rigid skeleton of the adamantanecarboxylic acid derivative contained in the composite antibacterial agent effectively reduces the adhesion and colonization of bacteria through steric hindrance and molecular recognition interference, and reduces the consumption pressure of the antibacterial agent; moreover, its rigid structure limits the rotational freedom of the polymer, and can reduce the erosion of the segments by the enzymes or acids secreted by bacteria; at the same time, the quaternized benzoxazine group contained in the composite antibacterial agent can provide long-term contact bactericidal ability, clear the residual microorganisms that break through the stereochemical barrier, and form a double protection.

[0015] Second: In the scheme, the cross-linked network of epoxy resin in the obtained coating constructs a rigid skeleton, ensuring that the coating has sufficient strength and hardness. The epoxy groups of the composite antibacterial agent participate in the curing process and endow the material with excellent ductility through flexible segments, significantly improving the elongation at break; therefore, through the synergistic effect of the "rigid skeleton + flexible energy dissipation unit", the coating obtains excellent flexibility while maintaining sufficient strength, meeting the mechanical property requirements under complex working conditions. Specific embodiments

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0017] Example 1: An antibacterial coating material for the inner wall of a pipeline comprises the following substances: by weight, 80 parts of bisphenol A epoxy resin, 10 parts of a composite antibacterial agent, 3 parts of nano-silica, 1 part of defoamer (BYK-071), 1 part of leveling agent (BYK-345), and 100 parts of tetrahydrofuran; Among them, the preparation process of the composite antibacterial agent is as follows: Mix 2 parts of glycidyl methacrylate, 15 parts of antibacterial monomer, 0.7 part of β-mercaptoethanol, 0.1 part of azobisisobutyronitrile, and 130 parts of tetrahydrofuran, bubble nitrogen for 30 min, then raise the temperature to 60 °C and react for 10 h. After the reaction is completed, cool to room temperature, precipitate the product with excessive methanol, and dry it under vacuum to obtain the composite antibacterial agent; Among them, the preparation process of the antibacterial monomer is as follows: S1: Mix 12 parts of guaiacol, 60 parts of absolute ethanol, 0.4 part of concentrated sulfuric acid, 10 parts of N-hydroxymethyl propionamide, and 1 part of anhydrous magnesium sulfate, stir evenly, react in a water bath at 35 °C for 24 h. After the reaction is completed, filter, wash, and recrystallize to obtain intermediate A; S2: Mix 12 parts of intermediate A, 9 parts of furfurylamine, 3 parts of paraformaldehyde, and 50 parts of absolute ethanol, raise the temperature to 90 °C, reflux and react for 4 h. Then use a rotary evaporator to evaporate the solution to remove ethanol, wash, and dry to obtain intermediate B; S3: Mix 25 parts of 11-bromo-1-undecanol, 18 parts of 1-adamantane carboxylic acid, 1 part of p-toluenesulfonic acid, and 15 parts of cyclohexane, raise the temperature to 80 °C, reflux and react for 10 h. After the reaction is completed, concentrate the mixture, dissolve the crude product in ethyl acetate, wash, dry, and purify to obtain intermediate C; S4: Add 25 parts of intermediate C and 12 parts of intermediate B to 40 parts of acetonitrile, raise the temperature to 60 °C, stir and react for 3 h. After the reaction is completed, cool to room temperature, and perform post-treatment to obtain the antibacterial monomer.

[0018] Example 2: An antibacterial coating material for the inner wall of a pipeline comprises the following substances: by weight, 100 parts of bisphenol A epoxy resin, 20 parts of a composite antibacterial agent, 4 parts of nano-silica, 2 parts of defoamer (BYK-071), 2 parts of leveling agent (BYK-345), and 120 parts of tetrahydrofuran; Among them, the preparation process of the composite antibacterial agent is as follows: Mix 3 parts of glycidyl methacrylate, 18 parts of antibacterial monomer, 0.9 part of β-mercaptoethanol, 0.2 part of azobisisobutyronitrile, and 150 parts of tetrahydrofuran, bubble nitrogen for 40 min, then raise the temperature to 70 °C and react for 12 h. After the reaction is completed, cool to room temperature, precipitate the product with excessive methanol, and dry it under vacuum to obtain the composite antibacterial agent; Among them, the preparation process of the antibacterial monomer is as follows: S1: Mix 15 parts of guaiacol, 70 parts of absolute ethanol, 0.5 part of concentrated sulfuric acid, 12 parts of N - hydroxymethyl propionamide, and 2 parts of anhydrous magnesium sulfate, stir evenly, react in a water bath at 35 °C for 24 h. After the reaction is completed, filter, wash, and recrystallize to obtain intermediate A; S2: Mix 15 parts of intermediate A, 10 parts of furfurylamine, 4 parts of paraformaldehyde, and 60 parts of absolute ethanol, raise the temperature to 100 °C, reflux and react for 5 h. Then use a rotary evaporator to evaporate the solution to remove ethanol, wash, and dry to obtain intermediate B; S3: Mix 28 parts of 11 - bromo - 1 - undecanol, 20 parts of 1 - adamantane carboxylic acid, 2 parts of p - toluenesulfonic acid, and 18 parts of cyclohexane, raise the temperature to 90 °C, reflux and react for 12 h. After the reaction is completed, concentrate the mixture, dissolve the crude product in ethyl acetate, wash, dry, and purify to obtain intermediate C; S4: Add 28 parts of intermediate C and 15 parts of intermediate B to 50 parts of acetonitrile, raise the temperature to 70 °C, stir and react for 4 h. After the reaction is completed, cool to room temperature, and perform post - treatment to obtain the antibacterial monomer.

[0019] Example 3: An antibacterial coating material for the inner wall of a pipeline comprises the following substances: by weight, 90 parts of bisphenol A epoxy resin, 15 parts of a composite antibacterial agent, 3.5 parts of nano - silica, 1.5 parts of a defoaming agent (BYK - 071), 1.5 parts of a leveling agent (BYK - 345), and 110 parts of tetrahydrofuran; Among them, the preparation process of the composite antibacterial agent is: Mix 2.5 parts of glycidyl methacrylate, 16.5 parts of the antibacterial monomer, 0.8 part of β - mercaptoethanol, 0.15 part of azobisisobutyronitrile, and 140 parts of tetrahydrofuran, bubble with nitrogen for 35 min, then raise the temperature to 65 °C and react for 11 h. After the reaction is completed, cool to room temperature, precipitate the product with excessive methanol, and dry in vacuum to obtain the composite antibacterial agent; Among them, the preparation process of the antibacterial monomer is: S1: Mix 13.5 parts of guaiacol, 65 parts of absolute ethanol, 0.45 part of concentrated sulfuric acid, 11 parts of N - hydroxymethyl propionamide, and 1.5 parts of anhydrous magnesium sulfate, stir evenly, react in a water bath at 35 °C for 24 h. After the reaction is completed, filter, wash, and recrystallize to obtain intermediate A; S2: Mix 13.5 parts of intermediate A, 9.5 parts of furfurylamine, 3.5 parts of paraformaldehyde, and 55 parts of absolute ethanol, raise the temperature to 95 °C, reflux and react for 4.5 h. Then use a rotary evaporator to evaporate the solution to remove ethanol, wash, and dry to obtain intermediate B; S3: Mix 26.5 parts of 11-bromo-1-undecanol, 19 parts of 1-adamantanecarboxylic acid, 1.5 parts of p-toluenesulfonic acid, and 16.5 parts of cyclohexane. Raise the temperature to 85 °C and reflux for 11 h. After the reaction is completed, concentrate the mixture. Dissolve the crude product in ethyl acetate, wash, dry, and purify to obtain intermediate C. S4: Add 26.5 parts of intermediate C and 13.5 parts of intermediate B to 45 parts of acetonitrile. Raise the temperature to 65 °C and stir for 3.5 h. After the reaction is completed, cool to room temperature and perform post-treatment to obtain the antibacterial monomer.

[0020] Comparative Example 1: Use nano-silver to replace the composite antibacterial agent, specifically as follows: An antibacterial coating material for the inner wall of a pipeline comprises the following substances: by weight, 90 parts of bisphenol A epoxy resin, 5 - 6 parts of nano-silver particles, 3.5 parts of nano-silica, 1.5 parts of defoaming agent (BYK-071), 1.5 parts of leveling agent (BYK-345), and 110 parts of tetrahydrofuran.

[0021] Comparative Example 2: In the preparation process of the composite antibacterial agent, do not introduce the three-dimensional structure of adamantane, specifically as follows: An antibacterial coating material for the inner wall of a pipeline comprises the following substances: by weight, 90 parts of bisphenol A epoxy resin, 15 parts of composite antibacterial agent, 3.5 parts of nano-silica, 1.5 parts of defoaming agent (BYK-071), 1.5 parts of leveling agent (BYK-345), and 110 parts of tetrahydrofuran; Among them, the preparation process of the composite antibacterial agent is: Mix 2.5 parts of glycidyl methacrylate, 16.5 parts of antibacterial monomer, 0.8 part of β-mercaptoethanol, 0.15 part of azobisisobutyronitrile, and 140 parts of tetrahydrofuran. Bubble with nitrogen for 35 min, then raise the temperature to 65 °C and react for 11 h. After the reaction is completed, cool to room temperature, precipitate the product with excess methanol, and dry in vacuum to obtain the composite antibacterial agent; Among them, the preparation process of the antibacterial monomer is: S1: Mix 13.5 parts of guaiacol, 65 parts of absolute ethanol, 0.45 part of concentrated sulfuric acid, 11 parts of N-hydroxymethylpropionamide, and 1.5 parts of anhydrous magnesium sulfate, stir evenly, and react in a 35 °C water bath for 24 h. After the reaction is completed, filter, wash, and recrystallize to obtain intermediate A; S2: Mix 13.5 parts of intermediate A, 9.5 parts of furfurylamine, 3.5 parts of paraformaldehyde, and 55 parts of absolute ethanol. Raise the temperature to 95 °C and reflux for 4.5 h. Then use a rotary evaporator to evaporate the solution to remove ethanol, wash, and dry to obtain the antibacterial monomer.

[0022] Detection test: Curing agent D400 was added to the coating materials obtained in the examples and comparative examples, and stirred evenly. Then, it was drop-coated on the pretreated substrate, pre-cured at room temperature for 6 h, and then cured in an oven at 60 °C for 10 h. Subsequently, relevant tests were carried out: (1) According to the standard ASTM D638, the coatings obtained in the examples and comparative examples were peeled off from the substrate to make dumbbell-shaped specimens (dimensions: 50 mm × 4 mm × 3 mm), and tested using a CMT4204 universal testing machine at a tensile rate of 50 mm / min at room temperature to obtain the elongation at break and tensile strength; (2) The coatings obtained in the examples and comparative examples were immersed in PBS buffer solution for 24 h, sterilized by ultraviolet for 30 min. Then, the samples were placed in a petri dish, added with bacterial solution, cultured at 37 °C for 24 h, and the number of colonies attached to the surface of the samples and the number of colonies in the blank control group were measured by the plate counting method, and then the antibacterial rate was calculated (the tested strains were Pseudomonas aeruginosa and Staphylococcus aureus); The data obtained are shown in the following table: Table 1 Conclusion: An antibacterial coating material for the inner wall of pipelines provided by the present invention, a composite antibacterial agent prepared by free radical polymerization reaction, combines a three-dimensional rigid skeleton and antibacterial active groups, significantly improving the mechanical strength and long-lasting antibacterial performance of the coating. Experimental data show that the elongation at break (132% - 136%) and antibacterial rate (Pseudomonas aeruginosa 98.67% - 99.01%, Staphylococcus aureus 99.07% - 99.15%) of the coatings in the examples are better than those in the comparative examples (for example, the elongation at break of the nano-silver coating is only 86% and the antibacterial rate is low), indicating that the material has excellent flexibility and high antibacterial ability while maintaining high tensile strength, and is suitable for the protection of the inner wall of pipelines under complex working conditions.

[0023] In the description of the specification, the description referring to terms such as "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0024] The above content is only an example and illustration of the present invention. Those skilled in the art of this technology can make various modifications or supplements to the described specific embodiments or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined by the claims of the present invention, they should fall within the protection scope of the present invention.

Claims

1. An antibacterial coating material for the inner wall of a pipeline, characterized in that: The antibacterial coating material comprises the following substances: by weight, 80-100 parts of bisphenol A epoxy resin, 10-20 parts of composite antibacterial agent, 3-4 parts of nano-silica, 1-2 parts of defoamer, 1-2 parts of leveling agent, and 100-120 parts of tetrahydrofuran; Among them, the preparation process of the composite antibacterial agent is as follows: Mix glycidyl methacrylate, antibacterial monomer, β-mercaptoethanol, azobisisobutyronitrile, and tetrahydrofuran, bubble nitrogen for 30-40 min, then raise the temperature to 60-70 °C and react for 10-12 h. After the reaction is completed, cool to room temperature, precipitate the product with excessive methanol, and dry it under vacuum to obtain the composite antibacterial agent.

2. The antibacterial coating material for the inner wall of a pipeline according to claim 1, characterized in that: The raw materials in the composite antibacterial agent include the following components: by weight, 2-3 parts of glycidyl methacrylate, 15-18 parts of antibacterial monomer, 0.7-0.9 parts of β-mercaptoethanol, 0.1-0.2 parts of azobisisobutyronitrile, and 130-150 parts of tetrahydrofuran.

3. The antibacterial coating material for the inner wall of a pipeline according to claim 1, characterized in that: The preparation process of the antibacterial monomer is as follows: S1: Mix guaiacol, absolute ethanol, concentrated sulfuric acid, N-hydroxymethyl propionamide, and anhydrous magnesium sulfate, stir evenly, and react in a 35 °C water bath for 24 h. After the reaction is completed, filter, wash, and recrystallize to obtain intermediate A; S2: Mix intermediate A, furfurylamine, paraformaldehyde, and absolute ethanol, raise the temperature to 90-100 °C, and reflux for 4-5 h. Then use a rotary evaporator to evaporate the solution to remove ethanol, wash, and dry to obtain intermediate B; S3: Mix 11-bromo-1-undecanol, 1-adamantanecarboxylic acid, p-toluenesulfonic acid, and cyclohexane, raise the temperature to 80-90 °C, and reflux for 10-12 h. After the reaction is completed, concentrate the mixture, dissolve the crude product in ethyl acetate, wash, dry, and purify to obtain intermediate C; S4: Add intermediate C and intermediate B to acetonitrile, raise the temperature to 60-70 °C, stir and react for 3-4 h. After the reaction is completed, cool to room temperature and perform post-treatment to obtain the antibacterial monomer.

4. The antibacterial coating material for the inner wall of a pipeline according to claim 3, characterized in that: The raw materials in intermediate A include the following components: by weight, 12-15 parts of guaiacol, 60-70 parts of absolute ethanol, 0.4-0.5 parts of concentrated sulfuric acid, 10-12 parts of N-hydroxymethyl propionamide, and 1-2 parts of anhydrous magnesium sulfate.

5. The antibacterial coating material for the inner wall of a pipeline according to claim 3, wherein: The raw materials in intermediate B include the following components: by weight, 12-15 parts of intermediate A, 9-10 parts of furfurylamine, 3-4 parts of paraformaldehyde, and 50-60 parts of absolute ethanol.

6. The antibacterial coating material for the inner wall of a pipeline according to claim 3, characterized in that: The raw materials in intermediate C include the following components: by weight, 25-28 parts of 11-bromo-1-undecanol, 18-20 parts of 1-adamantanecarboxylic acid, 1-2 parts of p-toluenesulfonic acid, and 15-18 parts of cyclohexane.

7. The antibacterial coating material for the inner wall of a pipeline according to claim 3, characterized in that: The raw materials in the antibacterial monomer include the following components: by weight, 25-28 parts of intermediate C, 12-15 parts of intermediate B, and 40-50 parts of acetonitrile.

8. The antibacterial coating material for the inner wall of a pipeline according to claim 1, wherein: The defoamer includes one or more of silicone defoamers, polyether defoamers, and fatty acid ester defoamers; the leveling agent includes one or more of acrylate leveling agents and silicone leveling agents.

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