Anti-ultraviolet calcium carbonate and preparation method thereof

Abstract

The invention relates to the field of anti-ultraviolet calcium carbonate, and discloses anti-ultraviolet calcium carbonate which is characterized by comprising the following components in parts by weight: 80-100 parts of calcium carbonate; 0.5 to 3 parts of benzotriazole (UV-326); 2 to 10 parts of CeO2 coated mica; 1-3 parts of a silane coupling agent; 0.5 to 1.5 parts of stearic acid; compared with the prior art, the invention has the advantages that the weather resistance and the long-acting stability are obviously improved through the synergistic bonding of the organic / inorganic ultraviolet agent, the process parameters are optimized, the problems of poor dispersity and weak interface bonding in the prior art are solved, and the weather-resistant and long-acting ultraviolet-resistant coating is suitable for the field of high-end outdoor materials.

Description

Technical Field

[0001] The invention relates to the technical field of anti-ultraviolet calcium carbonate, in particular to anti-ultraviolet calcium carbonate and a preparation method thereof. Background Art

[0002] Calcium carbonate (CaCO3) is a cheap inorganic filler widely used in industrial fields. However, ordinary calcium carbonate lacks UV resistance, which limits its application in outdoor weather-resistant materials.

[0003] In the prior art, physical blending is usually used to mix ultraviolet absorbers (such as nano-TiO2, ZnO) with calcium carbonate, but there are the following problems:

[0004] (1) Uneven dispersion: Nanoparticles tend to agglomerate, resulting in reduced UV shielding efficiency;

[0005] (2) Weak interface bonding: The inorganic filler has poor compatibility with the organic matrix and is easily detached from the matrix;

[0006] (3) Complex process: multiple steps of modification or the addition of a large amount of additives are required, which is costly. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the above technical difficulties and provide a calcium carbonate composite material that can achieve synergistic immobilization of organic / inorganic UV agents through chemical bonding, thereby solving the problems of dispersibility, interface bonding and full-band protection.

[0008] To solve the above technical problems, the present invention provides a technical solution: an anti-ultraviolet calcium carbonate, characterized in that it comprises the following components by weight: 80 to 100 parts of calcium carbonate; 0.5 to 3 parts of an organic ultraviolet absorber; 2 to 10 parts of an oxygen inorganic ultraviolet reflector; 1 to 3 parts of a silane coupling agent; 0.5 to 1.5 parts of stearic acid; and 0.5 to 1.5 parts of a solubilizer.

[0009] As an improvement, the calcium carbonate is nano-sized particles with a particle size of 100 to 500 nm and a surface area of ​​15 m 2 / g.

[0010] As an improvement, the organic ultraviolet absorber is benzotriazole (UV-326); the inorganic ultraviolet reflector is mica powder coated with cerium dioxide, the mica particle size is 10-50μm, the CeO2 coating layer is 20-50nm thick, and the UV-A reflectivity is ≥85%.

[0011] As an improvement, the silane coupling agent is one or both of γ-aminopropyltriethoxysilane (KH-550) and γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH-560), and the solubilizer is one of ethylene glycol and ethanol.

[0012] A method for preparing ultraviolet-resistant calcium carbonate comprises the following steps:

[0013] S1. Disperse calcium carbonate in deionized water and ultrasonicate for 30 to 60 minutes to obtain a uniform suspension;

[0014] S2. Add inorganic UV reflector, silane coupling agent and stearic acid to the suspension, stir at 60-70°C for 1 hour, dissolve organic UV absorber in solubilizer, add dropwise to the system, and stir at 70-80°C for 2 hours;

[0015] S3, spray drying the mixed solution, with an inlet temperature of 170-190°C and an outlet temperature of 80-100°C;

[0016] S4, heat treating the dried powder at 110-130° C. for 1-2 hours;

[0017] S5. Sieve to obtain UV-resistant calcium carbonate.

[0018] As an improvement, the power of the ultrasonic treatment in S1 is 200-400 W, and the solid content of the suspension is 10%-20%.

[0019] As an improvement, the feed rate of the spray drying in S3 is 5 to 10 L / h, and the atomization pressure is 0.3 to 0.5 MPa.

[0020] As an improvement, a 200-400 mesh vibrating screen is used for screening in S5.

[0021] The advantages of the present invention compared with the prior art are:

[0022] (1) Synergistic anti-ultraviolet mechanism: the organic agent (UV-326) efficiently absorbs UV-B (280-340nm); the inorganic agent (CeO2@mica) reflects UV-A (340-400nm); achieving full-band shielding from 280-400nm;

[0023] (2) Stable bonding structure: Silane coupling agent bridges calcium carbonate and UV agent, inhibiting migration (migration rate <0.5%);

[0024] (3) Process compatibility: step-by-step addition to avoid competitive adsorption, and low-temperature spray drying to protect the activity of the organic agent;

[0025] (4) Multifunctional integration: Modified calcium carbonate can be directly used in plastics and chemical fibers, reducing the amount of downstream additives added. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only 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 ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0027] Example 1

[0028] An anti-ultraviolet calcium carbonate, characterized by comprising the following components in parts by weight:

[0029] 80 parts of calcium carbonate; 0.5 parts of UV-326, 2 parts of CeO2@mica, 1 part of KH-550, 0.5 parts of stearic acid, and 0.5 parts of solubilizer.

[0030] The calcium carbonate is nano-sized particles with a particle size of 100 nm and a surface area of ​​≥15 m 2 / g;

[0031] The benzotriazole (UV-326) is an organic ultraviolet absorber, CeO2@mica, mica powder with cerium dioxide coated on the surface, the mica base particle size is 10-50 μm, the aspect ratio is ≥50, the cerium dioxide coating layer coverage is ≥90%, and the coating thickness is 20-50 nm.

[0032] The silane coupling agent is γ-aminopropyltriethoxysilane (KH-550) and γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH-560), and the solubilizer is ethylene glycol.

[0033] A method for preparing ultraviolet-resistant calcium carbonate comprises the following steps:

[0034] S1. Calcium carbonate was dispersed in deionized water and ultrasonically treated for 30 minutes to obtain a uniform suspension. The ultrasonic treatment power was 200 W and the solid content of the suspension was 10%;

[0035] S2. Add CeO2@mica, KH-550, silane coupling agent and stearic acid to the suspension and stir at 800 r / min at 60°C for 1 hour;

[0036] S3, spray drying the mixed solution, with an inlet temperature of 170°C, an outlet temperature of 80°C, a feed rate of 5 L / h, and an atomization pressure of 0.3 MPa;

[0037] S4, heat treating the dried powder at 110°C for 1 hour;

[0038] S5. Use a 200-mesh vibrating screen to obtain UV-resistant calcium carbonate.

[0039] Example 2

[0040] An anti-ultraviolet calcium carbonate, characterized by comprising the following components in parts by weight:

[0041] 90 parts of calcium carbonate; 1.5 parts of UV-1577, 3 parts of CeO2@mica powder (mica particle size 20μm, CeO2 coating layer thickness 30nm), 2 parts of KH-560, 1 part of stearic acid, and 1 part of solubilizer.

[0042] The calcium carbonate is nano-sized particles with a particle size of 100 nm and a surface area of ​​≥15 m 2 / g;

[0043] The benzotriazole (UV-326) is an organic ultraviolet absorber, CeO2@mica (mica powder coated with cerium dioxide), the mica base particle size is 10-50 μm, the aspect ratio is ≥50, the cerium dioxide coating layer coverage is ≥90%, and the coating thickness is 20-50 nm.

[0044] The silane coupling agent is gamma-aminopropyltriethoxysilane (KH-550), and the solubilizer is ethylene glycol.

[0045] A method for preparing ultraviolet-resistant calcium carbonate comprises the following steps:

[0046] S1. Calcium carbonate was dispersed in deionized water and ultrasonically treated for 45 minutes to obtain a uniform suspension. The ultrasonic treatment power was 300 W and the solid content of the suspension was 15%;

[0047] S2. Add CeO2@mica powder (pre-dried), KH-560, and stearic acid to the suspension and stir at 65°C for 1 hour. Dissolve UV-1577 in ethylene glycol and add dropwise, stirring at 75°C for 2 hours.

[0048] S3, spray drying the mixed solution, with an inlet temperature of 180°C, an outlet temperature of 90°C, a feed rate of 8 L / h, and an atomization pressure of 0.4 MPa;

[0049] S4, heat treating the dried powder at 120°C for 1.5 hours;

[0050] S5. Use a 300-mesh vibrating screen to obtain UV-resistant calcium carbonate.

[0051] Example 3

[0052] An anti-ultraviolet calcium carbonate, characterized by comprising the following components in parts by weight:

[0053] 100 parts of calcium carbonate; 3 parts of UV-326, 4 parts of CeO2@mica powder, mica particle size 50μm, CeO2 coating layer thickness 50nm, 3 parts of KH-550, 1.5 parts of stearic acid, and 1.5 parts of solubilizer.

[0054] The calcium carbonate is nano-sized particles with a particle size of 100 nm and a surface area of ​​≥15 m 2 / g;

[0055] The benzotriazole (UV-326) is an organic ultraviolet absorber, CeO2@mica (mica powder coated with cerium dioxide), the mica base particle size is 10-50 μm, the aspect ratio is ≥50, the cerium dioxide coating layer coverage is ≥90%, and the coating thickness is 20-50 nm.

[0056] The silane coupling agent is γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH-560), and the solubilizer is ethanol.

[0057] A method for preparing ultraviolet-resistant calcium carbonate comprises the following steps:

[0058] S1. Calcium carbonate was dispersed in deionized water and ultrasonically treated for 60 minutes to obtain a uniform suspension. The ultrasonic treatment power was 400 W and the solid content of the suspension was 20%;

[0059] S2. Add CeO2@mica powder, KH-550, and stearic acid to the suspension and stir at 70°C for 1 hour. Dissolve UV-326 in ethylene glycol and add dropwise, stirring at 80°C for 2 hours.

[0060] S3, spray drying the mixed solution, with an inlet temperature of 190°C, an outlet temperature of 100°C, a feed rate of 10 L / h, and an atomization pressure of 0.5 MPa;

[0061] S4, heat treating the dried powder at 130°C for 2 hours;

[0062] S5. Use a 400-mesh vibrating screen to obtain UV-resistant calcium carbonate.

[0063] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0064] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

[0065] The above description of the present invention and its embodiments is non-limiting. In short, if a person skilled in the art is inspired by the above description and, without departing from the purpose of the present invention, designs structures and embodiments similar to the technical solution without creative design, they shall fall within the scope of protection of the present invention.

Claims

1. An anti-ultraviolet calcium carbonate, characterized in that: The following components are included by weight: 80-100 parts of calcium carbonate; Benzotriazole (UV-326) 0.5-3 parts; CeO2@mica 2-10 parts; 1 to 3 parts of silane coupling agent; 0.5-1.5 parts of stearic acid; 0.5 to 1.5 parts of solubilizer.

2. The UV-resistant calcium carbonate according to claim 1, wherein: The calcium carbonate is nano-sized particles with a particle size of 100 to 500 nm and a surface area of ​​15 m 2 / g.

3. The UV-resistant calcium carbonate according to claim 1, wherein: The benzotriazole (UV-326) is an organic ultraviolet absorber, the surface of CeO2@mica is coated with mica powder of cerium dioxide, the mica base particle size is 10-50 μm, the diameter-to-thickness ratio is ≥50, the coverage rate of the cerium dioxide coating layer is ≥90%, and the coating thickness is 20-50 nm.

4. The UV-resistant calcium carbonate according to claim 1, wherein: The silane coupling agent is one or both of gamma-aminopropyltriethoxysilane (KH-550) and gamma-(2,3-epoxypropoxy)propyltrimethoxysilane (KH-560), and the solubilizer is one of ethylene glycol and ethanol.

5. The method for preparing an anti-ultraviolet calcium carbonate according to any one of claims 1 to 4, wherein: The following steps are involved: S1. Disperse calcium carbonate in deionized water and ultrasonicate for 30 to 60 minutes to obtain a uniform suspension; S2. Add an inorganic UV reflector, a silane coupling agent, and stearic acid to the suspension, and stir at 60-70°C for 1 hour; then dissolve the organic UV absorber in a solubilizer, slowly add it dropwise to the system, and continue stirring at 70-80°C for 2 hours; S3, spray drying the mixed solution. S4, heat-treating the dried powder at 110-130° C. for 1-2 hours to promote the coupling reaction and reduce volatilization; S5, sieving to obtain the finished product.

6. The method for preparing an ultraviolet-resistant calcium carbonate according to claim 1, wherein: The power of the ultrasonic treatment in S1 is 200-400 W, and the solid content of the suspension is 10%-20%.

7. The method for preparing an ultraviolet-resistant calcium carbonate according to claim 1, wherein: The feed rate of the spray drying in S3 is 5-10 L / h, the inlet temperature is 170-190°C to avoid decomposition of the organic agent, the outlet temperature is 80-100°C; and the atomization pressure is 0.3-0.5 MPa.

8. The method for preparing an ultraviolet-resistant calcium carbonate according to claim 1, wherein: The screening in S5 adopts 200-400 mesh vibrating screen.