Modified calcium carbonate powder antibacterial coating and preparation method thereof

Abstract

The invention relates to the technical field of powder coating preparation, in particular to a modified calcium carbonate powder antibacterial coating and a preparation method thereof. The modified calcium carbonate powder is prepared from, by weight, 100 parts of calcium carbonate powder and 3-6 parts of blumea balsamifera oil, and the average particle size of the calcium carbonate powder is 10-20 micrometers. The blumea balsamifera oil and the calcium carbonate powder are mixed, so that the blumea balsamifera oil is attached to the calcium carbonate powder, the calcium carbonate powder is modified, and the calcium carbonate powder also has certain antibacterial ability.

Description

Technical Field

[0001] The present application relates to the technical field of powder coating preparation, and in particular to a modified calcium carbonate powder antibacterial coating and a preparation method thereof. Background Art

[0002] Calcium carbonate is an important type of functional inorganic filler with the advantages of low price, abundant reserves, stable performance, easy processing, and non-toxicity. It can significantly improve the processing performance and physical properties of materials and reduce production costs, etc. It is widely used in coatings, plastics, rubber, papermaking and other fields.

[0003] As people's living standards continue to improve, their requirements for the quality of life and hygiene are getting higher and higher. How to effectively resist and remove bacteria is a challenge to modern life. The antibacterial coating industry is still in the development stage. The antibacterial agents used in existing powder coatings are mainly silver antibacterial agents, which use the bactericidal effect of silver ions. However, the silver ions in this type of antibacterial agent are easily dissolved, and the antibacterial performance is difficult to meet people's ideal requirements. Summary of the invention

[0004] In order to solve the problem that the antibacterial performance of existing powder coatings is difficult to meet people's ideal requirements, the present application provides a modified calcium carbonate powder for the preparation of antibacterial coatings. The modified calcium carbonate powder is modified by multiple bactericidal components in linalool to improve the antibacterial ability.

[0005] In a first aspect, the present application provides a modified calcium carbonate powder, which adopts the following technical solution: A modified calcium carbonate powder, whose raw materials include the following components in parts by weight: 100 parts of calcium carbonate powder and 3-6 parts of linalool oil; the average particle size of the calcium carbonate powder is 10-20 mu m.

[0006] By adopting the above technical scheme, Ailanthus flavonoids oil contains a variety of compounds such as terpenes, fatty acids, phenols, ketones, etc., among which terpenes can inhibit the electron transfer, proton translocation, phosphorylation and other enzyme-dependent reactions of microorganisms; phenolic compounds destroy the enzymatic matrix of microbial energy production and cell component synthesis, change nutrient absorption and electron transfer, and affect the synthesis of genetic material, thereby inhibiting microbial growth.

[0007] The average particle size of the calcium carbonate powder is 10-20 μm. This particle size range enables the powder to have good dispersibility and filling properties, which is conducive to the adhesion of the blumen oil to the calcium carbonate powder.

[0008] The present application mixes the linalool oil with calcium carbonate powder so that the linalool oil adheres to the calcium carbonate powder, thereby modifying the calcium carbonate powder and making the calcium carbonate powder have a certain antibacterial ability.

[0009] Preferably, the modified calcium carbonate powder further comprises a cationic surfactant, and the cationic surfactant comprises a quaternary ammonium salt type cationic surfactant and a heterocyclic type cationic surfactant.

[0010] By adopting the above technical scheme, calcium carbonate is an inorganic substance with hydrophilic surface; while linalool is a complex organic substance with lipophilic surface. Due to the large difference in chemical properties between the two, their compatibility is relatively poor. Cationic surfactants have a special molecular structure, with a hydrophilic group (such as quaternary ammonium salts, ammonium salts and other cationic parts) at one end and a hydrophobic group (such as long-chain alkyl groups) at the other end. In the solution, the hydrophilic group of the cationic surfactant faces the water phase, and the hydrophobic group faces the air or oil phase. This structure enables the cationic surfactant to form a "bridge" between calcium carbonate powder and linalool, promoting contact and mixing between the two by reducing surface tension.

[0011] Preferably, the weight portion of the cationic surfactant is 0.5-2 parts.

[0012] By adopting the above technical solution, the cationic surfactant plays a bridging role between the calcium carbonate powder and the linalool oil, promoting the compatibility between the two. If the content is too low, it may not be able to fully cover the surface of the calcium carbonate powder, resulting in insufficient compatibility with the linalool oil, affecting the performance of the product.

[0013] The content of cationic surfactant does not need to be too high, because at this time the compatibility of calcium carbonate powder and Ailanthus oil has been sufficiently improved, and there is no need to continue adding cationic surfactant. Preferably, the cationic surfactant is a quaternary ammonium salt cationic surfactant.

[0014] By adopting the above technical scheme, the quaternary ammonium salt type cationic surfactant itself has a broad spectrum of bactericidal ability, can kill or inhibit the growth of microorganisms such as bacteria, fungi, viruses. Its bactericidal mechanism is mainly through the negative charge interaction of cation and bacterial surface, adsorption and aggregation on the bacterial cell wall, producing a room resistance effect causing bacterial growth to be inhibited and die. Meanwhile, the hydrophobic alkyl of quaternary ammonium salt can also act on the hydrophilic group of bacteria, change the permeability of bacterial cell membrane, cause the dissolution and death of cells. Therefore, in modified calcium carbonate powder, adding quaternary ammonium salt type cationic surfactant can not only improve the compatibility of calcium carbonate powder and Blumea balsamina oil, but also further improve the antibacterial ability of product by virtue of its bactericidal property.

[0015] Preferably, the weight portion of the quaternary ammonium salt cationic surfactant is 0.8-1.5 parts.

[0016] By adopting the above technical scheme, the quaternary ammonium salt cationic surfactant plays a bridge role between the calcium carbonate powder and the Blumea balsamifera oil, and promotes the compatibility of the two. If the content is too low, it may not be able to fully cover the surface of the calcium carbonate powder, resulting in insufficient compatibility with Blumea balsamifera oil, affecting the uniformity and stability of the product. In addition, the quaternary ammonium salt cationic surfactant itself has a bactericidal ability, and it can also sterilize while improving the calcium carbonate powder and Blumea balsamifera oil, so the addition amount is higher than that of other cationic surfactants.

[0017] The content of cationic surfactant does not need to be too high, because at this time the compatibility of calcium carbonate powder and Ailanthus oil has been fully improved, and the antibacterial ability is difficult to continue to increase, so there is no need to continue to add cationic surfactant. Preferably, the quaternary ammonium salt type cationic surfactant includes dodecyldimethylbenzylammonium chloride and dodecyltrimethylammonium chloride.

[0018] In a second aspect, the present application provides a method for preparing modified calcium carbonate powder, using the following technical solution: A method for preparing modified calcium carbonate powder, used for preparing the modified calcium carbonate powder, comprises the following steps: heating and mixing the calcium carbonate powder, linalool and cationic surfactant in a formula amount to obtain the modified calcium carbonate powder; the heating temperature of the heating and mixing is 80-110°C.

[0019] By adopting the above technical solution, heating can accelerate the movement of molecules, so that the interaction between calcium carbonate powder, linalool and cationic surfactant is more complete. This helps to form a more uniform and stable mixture and improve the performance of the product. Cationic surfactant can better play its dispersing role under heating conditions and prevent calcium carbonate powder from agglomerating.

[0020] Blumea balsamifera oil is a complex organic substance with a certain range of thermal stability. Cationic surfactants also have a certain degree of thermal stability. Within the temperature range of 80-110°C, Blumea balsamifera oil and cationic surfactants can maintain their activity and will not lose their surface activity or decompose due to excessively high temperatures.

[0021] If the heating temperature is too high, it may cause adverse reactions between the linalool oil and the cationic surfactant, such as oxidation and decomposition. These adverse reactions may reduce the performance of the product and even produce harmful substances. Therefore, controlling the heating temperature within the range of 80-110℃ can avoid the occurrence of these high temperature side effects.

[0022] In a third aspect, the present application provides a modified calcium carbonate powder antibacterial coating, which adopts the following technical solution: A modified calcium carbonate powder antibacterial coating comprises the following components in parts by weight: 45 parts of the modified calcium carbonate powder mentioned above, 39-49 parts of epoxy resin, 3-4 parts of curing agent, 0.3-1 part of benzoin, 0.7-1.2 parts of leveling agent and 0.2-0.4 parts of dispersant.

[0023] In a fourth aspect, the present application provides a method for preparing a modified calcium carbonate powder antibacterial coating, using the following technical solution: A method for preparing a modified calcium carbonate powder antibacterial coating, which is used to prepare the modified calcium carbonate powder antibacterial coating, comprises the following steps: Mixing: Mix the modified calcium carbonate powder, epoxy resin, curing agent, benzoin, leveling agent and dispersant in the formula amount to obtain a mixture; Melting and crushing: the mixture is melted and extruded, and then crushed and ground to obtain a modified calcium carbonate powder antibacterial coating; the melting temperature range is 105-115°C.

[0024] By adopting the above technical solution, each component is evenly distributed during mixing, laying the foundation for the subsequent melting process. The melting temperature range is 105-115°C. Within this temperature range, each component in the mixture can be fully melted to form a uniform melt. At a melting temperature of 105-115°C, each component can remain stable and will not decompose or deteriorate due to excessive temperature.

[0025] In summary, this application has the following beneficial effects: 1. Since the present application mixes the linalool oil with the calcium carbonate powder, so that the linalool oil adheres to the calcium carbonate powder, thereby modifying the calcium carbonate powder, the calcium carbonate powder also has a certain antibacterial ability; 2. This application improves the compatibility of calcium carbonate powder and linalool oil by adding cationic surfactants, thereby improving the antibacterial ability of the coating; 3. This application adds a quaternary ammonium salt cationic surfactant and utilizes the bactericidal ability of the quaternary ammonium salt cationic surfactant itself, which can more effectively improve the antibacterial ability of the coating compared to other cationic surfactants. DETAILED DESCRIPTION

[0026] The raw materials in this application include the following parts: Calcium carbonate: a commercially available product with CAS No. 471-34-1; Ai Na sesame oil: Use commercially available products with an active ingredient content of ≥ 99%; Dodecyl dimethyl benzyl ammonium chloride: a commercially available product with CAS number 139-07-1; Dodecyltrimethylammonium chloride: a commercially available product with CAS number 112-00-5; Heterocyclic cationic surfactants: Heterocyclic cationic surfactants include tetraethylammonium chloride and benzyltriethylammonium chloride. This application uses the commercially available tetraethylammonium chloride product with CAS number 56-34-8 as an example; Epoxy resin: a commercial product with CAS number 61788-97-4 is used; Curing agent: TGIC curing agent is used; Benzoin: commercially available products are used; Leveling agent: Use leveling agent GLP588; Dispersant: Use dispersant NC; The present application is further described in detail below in conjunction with embodiments and comparative examples.

[0027] Example 1 A method for preparing modified calcium carbonate powder comprises the following steps: 100 g of calcium carbonate powder (average particle size 15 μm) and 5 g of linalool were heated and mixed together at a heating temperature of 100° C. and stirred at 300 rpm for 1 hour to obtain modified calcium carbonate powder.

[0028] A method for preparing a modified calcium carbonate powder antibacterial coating comprises the following steps: Mixing: add 45 g of modified calcium carbonate powder, 45 g of epoxy resin, 3.5 g of curing agent, 0.6 g of benzoin, 1 g of leveling agent, and 0.3 g of dispersant into a mixer and mix for 5 min to obtain a mixture; Melting and crushing: The mixture is melted and extruded, the melting temperature range is 105-115°C, the temperature of zone I is 105-110°C, and the temperature of zone II is 110-115°C, and then broken into flakes, and then ground in a grinder to obtain modified calcium carbonate powder antibacterial coating.

[0029] Example 2-3 Example 2-3 Based on the preparation method of Example 1, the content of each component of the modified calcium carbonate powder antibacterial coating was adjusted, and the specific adjustment is shown in Table 1.

[0030] Comparative Example 1 In Comparative Example 1, the modified calcium carbonate powder was replaced with calcium carbonate powder, and other conditions remained unchanged.

[0031] Table 1 Content and performance test table of each component of modified calcium carbonate powder antibacterial coating of Examples 1-3 and Comparative Example 1 project Example 1 Example 2 Example 3 Comparative Example 1 Modified calcium carbonate powder / g 45 45 45 / Epoxy resin / g 45 39 49 45 Curing agent / g 3.5 3 4 3.5 Benzoin / g 0.6 0.3 1 0.6 Leveling agent / g 1 0.7 1.2 1 Dispersant / g 0.3 0.2 0.4 0.3 Antibacterial rate / % 93.6 92.1 93.2 56.9 Performance Test The modified calcium carbonate powder antibacterial coatings of Examples 1-3 and Comparative Example 1 were subjected to the following performance tests. The test results are shown in Table 1.

[0032] Antibacterial rate The antibacterial rate is tested using GB / T21866-2008 "Determination of antibacterial properties and antibacterial effects of antibacterial coatings (paint films)".

[0033] Referring to Table 1, by comparing Examples 1-3 with Comparative Example 1, it can be seen that compared with Comparative Example 1, the antibacterial rates of Examples 1-3 are much higher than those of Comparative Example 1, indicating that the modified calcium carbonate powder can improve the antibacterial rate of the coating.

[0034] In addition, by comparing Examples 1-3, it is found that Example 1 has the best performance, so Example 1 is preferred.

[0035] Embodiment 4-7 Example 4-5 Based on the preparation method of Example 1, the amount of Blumea balsamina oil added was adjusted. The specific adjustments are shown in Table 2.

[0036] In Example 6-7, based on the preparation method of Example 1, the average particle size of the calcium carbonate powder was adjusted. The specific adjustment is shown in Table 2.

[0037] Comparative Examples 2-3 Comparative Example 2 Based on the preparation method of Example 1, the amount of Blumea sesame oil added was adjusted, and the specific adjustment is shown in Table 2.

[0038] Comparative Example 3 Based on the preparation method of Example 1, the average particle size of the calcium carbonate powder was adjusted, and the specific adjustment is shown in Table 2.

[0039] The modified calcium carbonate powder antibacterial coatings of Examples 4-7 and Comparative Examples 2-3 were subjected to the above performance tests, and the test results are shown in Table 2.

[0040] Table 2 The amount of linalool added and the average particle size of calcium carbonate powder and performance test table of Example 1, Examples 4-7 and Comparative Examples 2-7 Referring to Table 2, by comparing Example 1, Examples 4-7 and Comparative Examples 2-3, it can be seen that as the amount of Blumea balsamina oil added increases, the antibacterial rate of the modified calcium carbonate powder antibacterial coating gradually increases and then tends to be stable.

[0041] As the average particle size of calcium carbonate powder becomes larger and larger, the antibacterial rate of modified calcium carbonate powder antibacterial coating shows a trend of first increasing and then decreasing. This may be because as the average particle size of calcium carbonate powder becomes larger and larger, aina sesame oil becomes increasingly difficult to be compatible with calcium carbonate powder, resulting in a downward trend in the antibacterial rate after exceeding a certain range.

[0042] Embodiment 8-13 Example 8 Based on the preparation method of Example 1, 1.5 g of dodecyl dimethyl benzyl ammonium chloride was mixed with calcium carbonate powder and Blumea balsamifera oil, and other conditions remained unchanged.

[0043] Examples 9-12 are based on the preparation method of Example 8, and the amount of dodecyl dimethyl benzyl ammonium chloride added is adjusted. The specific adjustments are shown in Table 3.

[0044] Example 13 Based on the preparation method of Example 1, 1.5 g of dodecyltrimethylammonium chloride was mixed with calcium carbonate powder and Blumea balsamifera oil, and other conditions remained unchanged.

[0045] Comparative Example 4 Comparative Example 4 Based on the preparation method of Example 1, 1.5 g of dodecyl dimethyl benzyl ammonium chloride was mixed with calcium carbonate powder, and Blumea balsamifera oil was not added, while other conditions remained unchanged.

[0046] The modified calcium carbonate powder antibacterial coatings of Examples 8-13 and Comparative Example 4 were subjected to the above performance tests, and the test results are shown in Table 3 respectively.

[0047] Table 3 Addition amount and performance test table of dodecyl dimethyl benzyl ammonium chloride of Example 1, Examples 8-13 and Comparative Example 4 Referring to Table 3, by comparing Example 1, Examples 8-13 and Comparative Example 4, it can be seen that adding a quaternary ammonium salt type cationic surfactant is more conducive to improving the antibacterial performance of the modified calcium carbonate powder antibacterial coating.

[0048] Compared with Comparative Example 4, the antibacterial rates of Example 1 and Examples 8-13 are all higher than that of Comparative Example 4, indicating that adding dodecyl dimethyl benzyl ammonium chloride alone is still difficult to effectively enhance the antibacterial properties of calcium carbonate powder.

[0049] As the amount of dodecyldimethylbenzyl ammonium chloride added continues to increase, the antibacterial rate shows a trend of first increasing and then tending to a stable state. This may be because as the amount of dodecyldimethylbenzyl ammonium chloride added continues to increase, dodecyldimethylbenzyl ammonium chloride not only improves the compatibility between calcium carbonate powder and linalool oil, but dodecyldimethylbenzyl ammonium chloride itself has a certain bactericidal ability, thereby greatly improving the antibacterial properties of the modified calcium carbonate powder antibacterial coating.

[0050] Examples 14-18 Example 14 Based on the preparation method of Example 8, 1.5 g of dodecyldimethylbenzylammonium chloride was replaced with 1.5 g of tetraethylammonium chloride, and other conditions remained unchanged.

[0051] Examples 15-18 are based on the preparation method of Example 14, with the addition amount of tetraethylammonium chloride adjusted. The specific adjustments are shown in Table 4.

[0052] The modified calcium carbonate powder antibacterial coatings of Examples 14-18 were subjected to the above performance tests, and the test results are shown in Table 4.

[0053] Table 4 Addition amount and performance test table of tetraethylammonium chloride of Example 1, Example 8 and Examples 14-18 Referring to Table 4, by comparing Example 1, Example 8 and Examples 14-18, it can be seen that the use of tetraethylammonium chloride can also improve the performance of the modified calcium carbonate powder antibacterial coating, but not as good as dodecyl dimethyl benzyl ammonium chloride.

[0054] As the amount of tetraethylammonium chloride added continued to increase, the antibacterial rate showed a trend of rising and then tending to a stable state. This may be because as the amount of tetraethylammonium chloride added continued to increase, the compatibility between calcium carbonate powder and linalool oil continued to improve, thereby greatly improving the antibacterial properties of the modified calcium carbonate powder antibacterial coating.

[0055] Examples 19-20 In Examples 19-20, based on the preparation method of Example 1, the heating temperature of the heating mixing is adjusted. The specific adjustments are shown in Table 5.

[0056] Comparative Examples 5-6 Comparative Example 5-6 is based on the preparation method of Example 1, and the heating temperature of the heating mixing is adjusted. The specific adjustments are shown in Table 5.

[0057] The modified calcium carbonate powder antibacterial coatings of Examples 19-20 and Comparative Examples 5-6 were subjected to the above performance tests, and the test results are shown in Table 5, respectively.

[0058] Table 5 Heating temperature and performance test table of Example 1, Examples 19-20 and Comparative Examples 5-6 project Example 1 Embodiment 19 Embodiment 20 Comparative Example 5 Comparative Example 6 Heating temperature / ℃ 100 80 110 70 120 Antibacterial rate / % 93.6 90.5 91.9 89.4 87.6 Referring to Table 5, it can be seen from Comparative Examples 1, Examples 19-20 and Comparative Examples 5-6 that, as the heating temperature continues to rise, the antibacterial rate presents a trend of first rising and then falling. It is possible that as the heating temperature continues to rise, heating can accelerate the movement between molecules, making the interaction between calcium carbonate powder and Blumea balsamina oil more sufficient, thereby improving the antibacterial properties of the coating. When exceeding a certain range, the stability of Blumea balsamina oil is not enough, and decomposition is prone to occur, which reduces the antibacterial properties of the coating.

[0059] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A modified calcium carbonate powder, characterized in that The raw materials include the following components in parts by weight: 100 parts of calcium carbonate powder and 3-6 parts of linalool oil. The average particle size of the calcium carbonate powder is 10-20 micrometers.

2. The modified calcium carbonate powder according to claim 1, characterized in that: Also included are cationic surfactants, including quaternary ammonium salt type cationic surfactants and heterocyclic type cationic surfactants.

3. The modified calcium carbonate powder according to claim 2, characterized in that: The weight portion of the cationic surfactant is 0.5-2 parts.

4. The modified calcium carbonate powder according to claim 2, characterized in that: The cationic surfactant is a quaternary ammonium salt type cationic surfactant.

5. The modified calcium carbonate powder according to claim 4, characterized in that: The weight portion of the quaternary ammonium salt type cationic surfactant is 0.8-1.5 parts.

6. The modified calcium carbonate powder according to claim 4, characterized in that: The quaternary ammonium salt type cationic surfactant includes dodecyldimethylbenzylammonium chloride and dodecyltrimethylammonium chloride.

7. The method for preparing the modified calcium carbonate powder according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: heating and mixing the calcium carbonate powder, linalool and cationic surfactant in a prescribed amount to obtain modified calcium carbonate powder; the heating temperature of the heating and mixing is 80-110°C.

8. A modified calcium carbonate powder antibacterial coating, characterized in that: The invention comprises the following components in parts by weight: 45 parts of the modified calcium carbonate powder according to any one of claims 1 to 6, 39-49 parts of epoxy resin, 3-4 parts of curing agent, 0.3-1 part of benzoin, 0.7-1.2 parts of leveling agent and 0.2-0.4 parts of dispersant.

9. A method for preparing the modified calcium carbonate powder antibacterial coating according to claim 8, characterized in that: The following steps are involved: Mixing: Mix the modified calcium carbonate powder, epoxy resin, curing agent, benzoin, leveling agent and dispersant in the formula amount to obtain a mixture; Melting and crushing: the mixture is melted and extruded, and then crushed and ground to obtain a modified calcium carbonate powder antibacterial coating; the melting temperature range is 105-115°C.

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