Preparation method of modified barium sulfate powder, modified barium sulfate powder and application thereof

Abstract

The application provides a preparation method of modified barium sulfate powder, the modified barium sulfate powder and application thereof. The preparation method of the modified barium sulfate powder comprises the following steps: (1) preparation of hydroxyl-containing barium sulfate; (2) adding the hydroxyl-containing barium sulfate prepared in step (1), 6-fluoro-4-hydroxyquinoline-3-carboxylic acid and an acidic catalyst into a reaction kettle to perform esterification reaction, filtering, dehydrating and drying after the reaction is completed to prepare an intermediate A; (3) dispersing the intermediate A prepared in step (2) and water to prepare a slurry; and (4) performing silicon-aluminum coating on the slurry prepared in step (3), and then performing filtering, washing and drying to prepare the modified barium sulfate powder. When the modified barium sulfate powder prepared in the application is used to prepare paint, the modified barium sulfate powder not only has good storage stability, adhesion and whiteness, but also does not have precipitation and stratification phenomenon during long-time storage, and does not have coating peeling, and has good impact resistance and salt spray resistance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of fine inorganic chemical filler preparation, and particularly relates to a preparation method of modified barium sulfate powder, the modified barium sulfate powder and application thereof. BACKGROUND

[0002] Barium sulfate has structural characteristics such as quantum effect, size effect and surface effect, and when used in products, can increase the strength, hardness, wear resistance, weather resistance and other advantages of the products, and has broad application prospects in many industrial fields such as rubber, plastics, ink, paint, papermaking and other fields, and has broader application prospects in medicine, ceramics, cement, composite materials and other fields. However, due to the hydrophilic and oleophobic surface of barium sulfate, strong polarity, large specific area and high surface free energy, barium sulfate is prone to agglomeration, and therefore is difficult to uniformly disperse in the base material such as paint, has poor bonding force with the paint base material, is easy to cause interface defects, and leads to the decrease of the mechanical properties such as adhesion, salt mist resistance and storage stability of the paint.

[0003] In view of the problems of poor dispersion performance and easy agglomeration of the existing barium sulfate, the prior art usually adopts fatty acid, fatty acid salt or coupling agent to modify the surface of barium sulfate, but the modified barium sulfate still has partial agglomeration phenomenon, and has the problems of poor compatibility of the modified barium sulfate with the paint, weak interface layer between the particles and the matrix, and limited reinforcing effect of the filler, which affects the use of barium sulfate.

[0004] In view of the problems of the existing barium sulfate, how to modify the barium sulfate so that the prepared modified barium sulfate not only avoids the problem of agglomeration, but also has strong bonding force with the paint and improves the mechanical properties such as adhesion, salt mist resistance and storage stability of the paint, is a problem to be solved by the present application. SUMMARY

[0005] The present application aims to provide a preparation method of modified barium sulfate powder, the modified barium sulfate powder and application thereof, so as to solve the problems in the background art.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme: on the one hand, the present application provides a preparation method of modified barium sulfate powder, comprising the following steps:

[0007] (1) preparation of hydroxyl-containing barium sulfate;

[0008] (2) adding the hydroxyl-containing barium sulfate prepared in step (1), 6-fluoro-4-hydroxyquinoline-3-carboxylic acid and an acidic catalyst into a reaction kettle to perform esterification reaction, filtering, dehydrating and drying after the reaction is completed, to prepare intermediate A;

[0009] (3) dispersing the intermediate A prepared in step (2) and water to prepare a slurry;

[0010] (4) The slurry prepared in step (3) is subjected to silicon-aluminum coating, and then is filtered, washed and dried to prepare the modified barium sulfate powder.

[0011] As a further improvement, the method for preparing the barium sulfate containing hydroxyl group comprises the following steps:

[0012] The barium carbonate and water are ultrasonically dispersed to prepare a suspension, and then an initiator is added and uniformly mixed, and concentrated sulfuric acid is added dropwise to react. After the reaction is completed, the barium sulfate containing hydroxyl group is prepared by filtering, washing and drying.

[0013] As a further improvement, the initiator can be concentrated hydrochloric acid.

[0014] As a further improvement, in step (4), the slurry prepared in step (3) is subjected to silicon-aluminum coating, which comprises the following steps:

[0015] (4.1) The slurry prepared in step (3) is added to a reaction kettle with a pH of 9-10, and a sodium silicate solution is added dropwise. During the dropwise addition, the pH of the solution is maintained at 9-10. After the dropwise addition is completed, the system is aged at a temperature of 50-80℃ for 2-4h.

[0016] (4.2) The pH of the system in step (4.1) is adjusted to 5-8, and then a sodium aluminate solution is added dropwise. During the dropwise addition, the pH of the solution is maintained at 5-8. After the dropwise addition is completed, the system is aged at a temperature of 50-80℃ for 2-4h.

[0017] As a further improvement, the concentration of silicon ions in the sodium silicate solution is 0.1-0.25mol / L.

[0018] As a further improvement, the concentration of aluminum ions in the sodium aluminate solution is 0.3-0.5mol / L.

[0019] As a further improvement, in step (3), the content of the intermediate A in the slurry is 20-40wt%.

[0020] As a further improvement, the particle size of the barium carbonate is 10-100μm.

[0021] As a further improvement, in step (2), the reaction temperature is 60-80℃, and the reaction time is 1-3h.

[0022] On the other hand, the present application also provides a modified barium sulfate powder prepared by the method for preparing the modified barium sulfate powder.

[0023] On the other hand, the present application also provides an application of the modified barium sulfate powder in inks and coatings.

[0024] Compared with the prior art, the application has the beneficial effects that the modified barium sulfate powder prepared by the application has good storage stability, adhesion, whiteness, and will not have precipitation, delamination, coating peeling, corrosion, and improved mechanical properties of the prepared coating. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 Product particle size diagram of the modified barium sulfate powder of the application;

[0026] Figure 2 XRD diagram of the modified barium sulfate powder of the application. DETAILED DESCRIPTION

[0027] The application will be described in detail below with reference to specific embodiments. It should be noted that the following examples are examples of the application and are only used to illustrate the application, but not to limit the application. Other combinations and various modifications within the concept of the application can be made without departing from the spirit or scope of the application.

[0028] In the following examples, in addition to sodium silicate solution A, sodium aluminate solution A, and modified barium sulfate powder A-E, the remaining used compound monomers and related reagents can be purchased from the market, wherein the particle size of the used barium carbonate is 80 mu m; the dispersing agent is BYK-190 purchased from BYK Chemical; the defoaming agent is BYK-024 purchased from BYK Chemical; the pigment is Pigment Red SR2P purchased from Suncolor Chemical Industry (Shanghai) Co., Ltd.; the hydroxy acrylate resin is AH purchased from Hanpin Paint Industry (Shandong) Co., Ltd.; and the emulsifier is SAS-60 purchased from Guangzhou Baofa Chemical Co., Ltd.

[0029] The preparation method of the sodium silicate solution A comprises the following steps: adding deionized water to 1 mol of sodium silicate Na2O nSiO2, stirring until uniform, to obtain a sodium silicate solution with a silicon ion concentration of 0.2 mol / L.

[0030] The preparation method of the sodium aluminate solution A comprises the following steps: adding 1.5 mol of sodium hydroxide, 0.8 mol of aluminum, and 1 L of deionized water to a reaction kettle with a temperature of 60 DEG C, stirring under constant temperature until the sodium hydroxide and aluminum hydroxide are dissolved, filtering, and continuously adding deionized water to obtain a sodium aluminate solution with an aluminum ion concentration of 0.4 mol / L.

[0031] The preparation method of the modified barium sulfate powder A comprises the following steps:

[0032] (1) 5 mol of barium carbonate and 5 L of water were ultrasonically dispersed for 30 min to form a suspension, then 0.27 mol of hydrochloric acid with a mass fraction of 37% was added and uniformly mixed, and then concentrated sulfuric acid with a concentration of 98% was added dropwise for reaction, after the reaction was completed, the pH was 6, and then filtration, washing, and drying (drying temperature was 70°C, and reaction time was 5 h) were performed to obtain hydroxyl-containing barium sulfate;

[0033] (2) 2 mol of the hydroxyl-containing barium sulfate obtained in step (1), 2 mol of 6-fluoro-4-hydroxyquinoline-3-carboxylic acid, and 0.05 mol of diatomite were added into a reaction kettle for esterification reaction, the reaction was performed at a temperature of 80°C for 2 h, after the reaction was completed, filtration, dehydration, and drying were performed to obtain intermediate A;

[0034] (3) 1 mol of the intermediate A obtained in step (2) and water were dispersed to form a slurry with a concentration of 20 wt%;

[0035] (4) The slurry obtained in step (3) was added into a reaction kettle with a pH of 9, and 2 L of sodium silicate solution A was added dropwise, the pH of the solution was maintained at 9 during the dropwise addition, after the dropwise addition was completed, aging was performed at a temperature of 80°C for 2 h;

[0036] (4.2) The pH of the system in step (4.1) was adjusted to 6, then 1 L of sodium aluminate solution was added dropwise, the pH of the solution was maintained at 6 during the dropwise addition, after the dropwise addition was completed, aging was performed at a temperature of 80°C for 2 h, and then filtration, washing, and drying were performed to obtain modified barium sulfate powder A.

[0037] A method for preparing modified barium sulfate powder B, comprising the following steps:

[0038] (1) 5 mol of barium carbonate and 5 L of water were ultrasonically dispersed for 30 min to form a suspension, then 0.27 mol of hydrochloric acid with a mass fraction of 37% was added and uniformly mixed, and then concentrated sulfuric acid with a concentration of 98% was added dropwise for reaction, after the reaction was completed, the pH was 6, and then filtration, washing, and drying (drying temperature was 80°C, and reaction time was 4 h) were performed to obtain hydroxyl-containing barium sulfate;

[0039] (2) 2 mol of the hydroxyl-containing barium sulfate obtained in step (1), 2 mol of 6-fluoro-4-hydroxyquinoline-3-carboxylic acid, and 0.05 mol of diatomite were added into a reaction kettle for esterification reaction, the reaction was performed at a temperature of 70°C for 3 h, after the reaction was completed, filtration, dehydration, and drying were performed to obtain intermediate A;

[0040] (3) 1 mol of the intermediate A obtained in step (2) and water were dispersed to form a slurry with a concentration of 25 wt%;

[0041] (4) adding the slurry prepared in step (3) into a reactor with pH 9, and adding dropwise 2.1 L of sodium silicate solution A, maintaining the pH of the solution at 9 by adding dropwise oleum during the adding process, and aging for 1.5 h at 80℃ after the adding process;

[0042] (4.2) adjusting the pH of the system in step (4.1) to 5, then adding dropwise 1.2 L of sodium aluminate solution, maintaining the pH of the solution at 5 during the adding process, and aging for 2 h at 80℃ after the adding process, and then filtering, washing and drying to obtain modified barium sulfate powder B.

[0043] A method for preparing modified barium sulfate powder C, comprising the following steps:

[0044] (1) preparing a suspension by ultrasonic dispersion of 5 mol of barium carbonate and 5 L of water for 25 min, then adding 0.27 mol of 37% hydrochloric acid, mixing uniformly, and then adding dropwise 98% concentrated sulfuric acid to react, and after the reaction is completed, the pH is 6, and then filtering, washing and drying (drying temperature is 70℃, and reaction time is 5 h) to obtain hydroxyl-containing barium sulfate;

[0045] (2) adding 2 mol of the hydroxyl-containing barium sulfate prepared in step (1), 2 mol of 6-fluoro-4-hydroxyquinoline-3-carboxylic acid and 0.04 mol of diatomite into a reactor to perform esterification reaction, and the reaction is performed at 70℃ for 3 h, and after the reaction is completed, filtering, dehydrating and drying to obtain intermediate A;

[0046] (3) dispersing 1 mol of the intermediate A prepared in step (2) and water to prepare a 22 wt% slurry;

[0047] (4) adding the slurry prepared in step (3) into a reactor with pH 9, and adding dropwise 2.1 L of sodium silicate solution A, maintaining the pH of the solution at 9 by adding dropwise oleum during the adding process, and aging for 3 h at 80℃ after the adding process;

[0048] (4.2) adjusting the pH of the system in step (4.1) to 6, then adding dropwise 1.2 L of sodium aluminate solution, maintaining the pH of the solution at 6 during the adding process, and aging for 3 h at 80℃ after the adding process, and then filtering, washing and drying to obtain modified barium sulfate powder C.

[0049] A method for preparing modified barium sulfate powder D, comprising the following steps:

[0050] (1) 5 mol of barium carbonate and 5 L of water were ultrasonically dispersed for 30 min to prepare a suspension, then 0.27 mol of 37% mass fraction hydrochloric acid was added and uniformly mixed, and then concentrated sulfuric acid with a concentration of 98% was added dropwise to react, after the reaction was completed, the pH was 6, and then filtration, washing and drying (drying temperature was 70°C, and the reaction time was 5 h) were performed to prepare hydroxyl-containing barium sulfate;

[0051] (2) 2 mol of the hydroxyl-containing barium sulfate prepared in step (1), 2 mol of 6-fluoro-4-hydroxyquinoline-3-carboxylic acid and 0.05 mol of diatomite were added into a reaction kettle to perform esterification, the reaction temperature was 80°C, the reaction time was 2 h, after the reaction was completed, filtration, dehydration and drying were performed to prepare modified barium sulfate powder D.

[0052] A preparation method of modified barium sulfate powder E includes the following steps:

[0053] (1) 1 mol of barium sulfate was dispersed in water to prepare a 20% wt slurry;

[0054] (2) The slurry prepared in step (1) was added into a reaction kettle with a pH of 9, and 2 L of sodium silicate solution A was added dropwise, the pH of the solution was maintained at 9 during the dropwise addition, after the dropwise addition was completed, aging was performed at a temperature of 80°C for 2 h;

[0055] (3) The pH of the system in step (2) was adjusted to 6, then 1 L of sodium aluminate solution was added dropwise, the pH of the solution was maintained at 6 during the dropwise addition, after the dropwise addition was completed, aging was performed at a temperature of 80°C for 2 h, and then filtration, washing and drying were performed to prepare modified barium sulfate powder E.

[0056] The modified barium sulfate powder prepared in the present application was used to prepare coatings 1-6, and the raw materials used in the preparation of the coatings 1-6 were as follows: 10 g of water, 2 g of dispersant, 0.15 g of defoaming agent, 10 g of pigment, 8 g of modified barium sulfate powder, 55 g of hydroxyl acrylate resin and 0.5 g of emulsifier;

[0057] The modified barium sulfate powder used in the coatings 1-5 is shown in Table 1 below, and the coating 6 (comparative example 3) used unmodified barium sulfate:

[0058] Table 1

[0059] Coating 1 (Example 1) Modified barium sulfate powder A Coating 2 (Example 2) Modified barium sulfate powder B Coating 3 (Example 3) Modified barium sulfate powder C Coating 4 (Comparative Example 1) Modified barium sulfate powder D Coating 5 (Comparative Example 2) Modified barium sulfate powder E

[0060] The test methods are as follows:

[0061] Whiteness test: in accordance with national standard GB / T 5950-2008;

[0062] Coating storage stability test: 0.5L of coatings 1-6 was filled into a well-sealed storage tank, leaving about 10% space in the tank, and after sealing, it was placed in a constant temperature drying oven at (50±2)℃, and after 7 days, it was taken out and placed at (23±2)℃ for 3h, and the coating state before and after storage was compared;

[0063] Adhesion test: according to national standard GB / T 9286-1998;

[0064] Impact resistance test: according to national standard GB / T 1732-1993.

[0065] Salt spray resistance test: according to national standard GB1771-79.

[0066] The test results are shown in Table 2 as follows:

[0067] Table 2

[0068]

[0069] As can be seen from the comparison of Examples 1, Comparative Examples 1-3, the coating prepared using the modified barium sulfate powder provided by the present application has no precipitation and delamination phenomenon, has good storage stability, and the whiteness is also improved accordingly, even reaching more than 97%, and also has good adhesion, impact resistance and salt spray resistance, so that the prepared coating does not have coating peeling and corrosion phenomenon;

[0070] As can be seen from the comparison of Examples 1-3, the coating prepared using the modified barium sulfate powder prepared by the preparation method provided by the present application not only has good whiteness, but also has good adhesion, and does not have coating peeling phenomenon, and even after long-term storage, there is no precipitation and delamination phenomenon, and the salt spray resistance and impact resistance are good;

[0071] In summary, the modified barium sulfate powder prepared by the present application not only has good storage stability, adhesion, whiteness when used for preparing coatings, and does not have precipitation and delamination phenomenon after long-term storage, and also does not have coating peeling, and has good impact resistance and salt spray resistance, and does not have corrosion phenomenon, and improves the mechanical properties of the prepared coating.

[0072] The above embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and cannot limit the protection scope of the present application, and any equivalent changes or modifications made according to the spirit and essence of the present application should be covered within the protection scope of the present application.

Claims

1. A method for preparing modified barium sulfate powder, characterized in that: Includes the following steps: (1) Preparation of barium sulfate containing hydroxyl groups; (2) Add the hydroxyl-containing barium sulfate, 6-fluoro-4-hydroxyquinoline-3-carboxylic acid and acidic catalyst obtained in step (1) into the reaction vessel to carry out the esterification reaction. After the reaction is completed, filter, dehydrate and dry to obtain intermediate A. (3) Disperse the intermediate A obtained in step (2) with water to form a slurry; (4) After the slurry obtained in step (3) is coated with silicon aluminum, it is filtered, washed and dried to obtain modified barium sulfate powder. The method for preparing the hydroxyl-containing barium sulfate includes the following steps: Barium carbonate and water were ultrasonically dispersed to form a suspension. Then, an initiator was added and mixed evenly. Concentrated sulfuric acid was added dropwise to carry out the reaction. After the reaction was completed, the mixture was filtered, washed, and dried to obtain barium sulfate containing hydroxyl groups. In step (4), the slurry obtained in step (3) is coated with silicon-aluminum, which includes the following steps: (4.1) Add the slurry obtained in step (3) to the reaction vessel with pH 9-10, and add sodium silicate solution dropwise. During the dropwise addition, keep the pH of the solution at 9-10. After the dropwise addition is completed, age it at 50-80℃ for 2-4 hours. (4.2) Adjust the pH of the system in step (4.1) to 5-8, and then add sodium aluminate solution dropwise. During the dropwise addition, keep the pH of the solution at 5-8. After the dropwise addition is completed, age the solution at 50-80℃ for 2-4 hours.

2. The method for preparing modified barium sulfate powder according to claim 1, characterized in that: The concentration of silicon ions in the sodium silicate solution is 0.1-0.25 mol / L.

3. The method for preparing modified barium sulfate powder according to claim 1, characterized in that: The concentration of aluminum ions in the sodium aluminate solution is 0.3-0.5 mol / L.

4. The method for preparing modified barium sulfate powder according to claim 1, characterized in that: In step (3), the content of intermediate A in the slurry is 20-40 wt%.

5. The method for preparing modified barium sulfate powder according to claim 1, characterized in that: The barium carbonate has a particle size of 10-100 μm.

6. The method for preparing modified barium sulfate powder according to claim 1, characterized in that: In step (2), the reaction temperature is 60-80℃ and the reaction time is 1-3h.

7. Modified barium sulfate powder prepared by the method for preparing modified barium sulfate powder according to any one of claims 1-6.

8. The application of the modified barium sulfate powder according to claim 7 in coatings.

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