High dielectric fiber material, powder coating composition and preparation method

Abstract

The invention discloses a high dielectric fiber material, a powder coating composition and a preparation method. The high dielectric fiber material comprises a fiber material BaTi2O5, an inorganic filler and a modifier, wherein the inorganic filler comprises the following components in weight percentage: SiO2: 40-70%, Al2O3: 10-25%, Fe2O3: 0.1-5%, CaO: 2-10%, MgO: 1-5%, B2O3: 5-15%, the modifier comprises at least one or more silane modifiers, and the high dielectric powder composition comprises the high dielectric fiber material and the powder coating. The high dielectric fiber material and the powder coating composition of the invention have very high dielectric properties, filling the gap of high dielectric properties of functional powder coatings.

Description

Technical Field

[0001] The invention relates to the technical field of high dielectric materials, and in particular to a high dielectric fiber material, a powder coating composition and a preparation method thereof. Background Art

[0002] Powder coating is applied in powder form and forms a coating. The solid content can reach 100% and no solvent is used. Therefore, it can reduce environmental pollution, save resources, and has the characteristics of recyclability. Functional powder coating is a surface coating material with special functions and special uses. It can not only play the traditional protective and decorative roles, but also give the material various special functions, mainly including insulation, conductivity, anti-fouling, heat resistance, flame retardant, radiation protection and other functions. For the electrostatic powder spraying process, the key consideration is the acceptance of charge, maintenance of charge and charge distribution of powder coating particles, which directly affects the adsorption and deposition effect of powder on the workpiece. In addition, it is very important that the uncured powder coating must be able to withstand the mechanical vibration of the conveying mechanism without dropping powder. In fact, the dielectric constant of the powder coating is the main factor affecting the acceptance and retention of charge of powder particles.

[0003] The lower the dielectric constant of the powder, the easier it is for the particles to be charged, but also the easier it is to lose charge. This reflects the absorption of the powder on the workpiece. If the adsorption force is not strong, the powder will fall off after a slight vibration. For electrostatic spray powder coating, a high dielectric constant should be used as much as possible, which will greatly improve the adsorption of the powder and make the coating more uniform.

[0004] With the development of microelectronic devices and nanoelectronic devices, the storage of electrical energy has become an important research direction of dielectric materials. In particular, materials with good processing performance, high dielectric constant, low dielectric loss and high energy storage density have attracted widespread attention.

[0005] Ferroelectric materials have many properties such as dielectric, piezoelectric, ferroelectric, pyroelectric, photoelectric and nonlinear optics, and show broad application prospects in the fields of microelectronics, optoelectronics, integrated optics and micro-electromechanical systems. At present, the ferroelectrics widely studied and applied are mainly perovskite structures such as BaTiO3, PbTiO3, PbZr1-XTiXO3, etc. However, the low Curie temperature of BaTiO3 (about 410K) limits its application range, and PbTiO3 and PbZr1-XTiXO3 contain lead, which will cause harm to the environment and human health during preparation and use. Therefore, the lead-free ferroelectric material barium titanate (BaTi2O5) has attracted people's attention. Compared with traditional BaTiO3, BaTi2O5 has a dielectric constant that is 3 times larger than it, and a Curie temperature of up to 747K. It is a very promising high dielectric material, especially the fibrous BaTi2O5 material has a high-strength network structure that is resistant to stretching, tearing, impact and bending.

[0006] General ceramic materials require high-temperature sintering and their application range is limited, while functional powder coatings can be sprayed on electrical components, polymer materials, screen electrodes, VHF-UHF-RF coils, printed circuits, circuits, etc. to form high dielectric composite materials, which have broad application prospects. Therefore, it is necessary to develop a high dielectric fiber and powder coating composition to increase the high dielectric performance application of functional powder coatings. Summary of the invention

[0007] The object of the present invention is to provide a high dielectric fiber material, a powder coating composition and a preparation method to overcome one or more technical problems proposed in the prior art.

[0008] In order to achieve the above-mentioned invention object, the present invention proposes the following technical solutions:

[0009] A high dielectric fiber material (BaTi2O5-G), comprising a fiber material BaTi2O5, an inorganic filler and a modifier, wherein the diameter of the fiber material BaTi2O5 is 80-200 nm, and the inorganic filler comprises the following components in weight percentage:

[0010] SiO2:40-70%

[0011] Al2O3: 10-25%

[0012] Fe2O3: 0.1-5%

[0013] CaO: 2-10%

[0014] MgO: 1-5%

[0015] B2O3: 5-15%

[0016] The mass ratio of the fiber material to the inorganic filler is 1:1;

[0017] The modifier includes at least one or more silane modifiers, and the mass of the modifier accounts for 0.5-1.5% of the total mass of the fiber material and the inorganic filler.

[0018] In one or more embodiments of the present invention, the length of the fiber material is 1-15um, and the purity of BaTi2O5 is ≥99.5%. Such fiber material can improve the dielectric constant performance, and at the same time make the material have the characteristics of anti-stretching, anti-tearing, anti-impact, and anti-bending.

[0019] In one or more embodiments of the present invention, the modifier is at least one or more silane modifiers, preferably a composite modification of multiple silanes, one or more of epoxy silane, amino silane, and vinyl silane, and more preferably epoxy silane. It can react with the resin curing agent to improve the compatibility of the fiber material and the resin, and enhance the leveling and adhesion of the finished powder coating.

[0020] The present invention also provides a high dielectric powder coating composition, which comprises a high dielectric fiber material and a powder coating, wherein the mass ratio of the high dielectric fiber material to the powder coating is 1.2-5:10.

[0021] In one or more embodiments of the present invention, the mass content of the high dielectric fiber material in the high dielectric powder coating composition is 10.7%-33.3%.

[0022] In one or more embodiments of the present invention, the powder coating is commercially available powder coating interpon100.

[0023] The present invention also provides a method for preparing a high dielectric fiber material, which comprises the following preparation steps:

[0024] (1) using an organic solvent to dilute epoxy silane and stirring at high speed to obtain a silane modifier;

[0025] (2) melting the various components of the inorganic filler at 900-1400° C., cooling, and then ball milling and classifying;

[0026] (3) The fiber material and the inorganic filler are placed in a high-speed mixer, stirred at a low speed for a period of time, and then stirred at a high speed, and the silane modifier is added dropwise at a uniform speed, stirred and heated to 100-130° C. and kept warm for a certain period of time to obtain a high dielectric fiber material.

[0027] In one or more embodiments of the present invention, the low-speed stirring is stirring at a temperature of 60-70°C and a rotation speed of 300-500 r / min for 10-15 min, and the high-speed stirring is stirring at a rotation speed of 800-1000 r / min for 15-40 min; and the inorganic filler is used to increase the pencil hardness of the cured film.

[0028] In one or more embodiments of the present invention, when the organic solvent dilutes the epoxy silane, the mass ratio of the organic solvent to the epoxy silane is 2:1.

[0029] The present invention also proposes a method for preparing a high dielectric powder coating composition, which comprises adding the prepared high dielectric fiber material to the powder coating, mixing and stirring, extruding through a twin-screw machine, cooling and tableting, and powder classification to obtain a high dielectric powder coating composition, wherein the powder coating is a commercially available powder coating interpon100, and its particle size D100=35um.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows: the high dielectric fiber material and powder coating composition proposed in the present invention have very high dielectric properties, filling the gap in the high dielectric properties of functional powder coatings; at the same time, its fiber structure is resistant to stretching, tearing, impact and bending, and has good application prospects. The high dielectric fiber material and powder coating composition can be sprayed on the surface of metal, ceramic and polymer materials to form a high dielectric composite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a SEM image of the fiber material BaTi2O5 used in the embodiments of the present invention;

[0032] Figure 2 It is the XRD diagram of the fiber material BaTi2O5 used in the examples of the present invention. DETAILED DESCRIPTION

[0033] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0034] Unless explicitly stated otherwise, throughout the specification and claims, the term "comprise" or variations such as "include" or "comprising" etc. will be understood to include the stated elements or components but not to exclude other elements or components.

[0035] The present invention will be described in detail below in conjunction with the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional changes made by a person skilled in the art based on these embodiments are all within the scope of protection of the present invention.

[0036] Table 1 shows the ingredients and components of the high dielectric fiber materials and powder coating compositions in Examples 1 to 6 of the present application and Comparative Examples 1 to 4, as well as a comparison of the dielectric constant, dielectric loss and hardness of the obtained powder coating compositions.

[0037] The inorganic filler is prepared according to the following mass percentages: SiO2: 65%, Al2O3: 15.6%, Fe2O3: 0.1%, CaO: 3%, MgO: 4%, B2O3: 12.3%; after compounding, it is melted at 1000-1500°C, cooled, ball-milled, and classified to obtain an inorganic filler with D50=15um;

[0038] The fiber material is 1-15um in length, 80-200nm in diameter, and BaTi2O5 purity ≥ 99.5%, such as Figure 1 and Figure 2 shown.

[0039] The powder coating is a conventional powder coating interpon100 purchased from the market, with a particle size of D100 = 35 um.

[0040] A certain amount of fiber material and inorganic filler are put into a high-speed mixer, first stirred at 60-70°C at a low speed of 300-500r / min for 10-15min, then stirred at a high speed of 800-1000r / min, and at the same time, a silane modifier is added dropwise at a uniform speed, and then the temperature is raised to about 100-130°C, stirred for 15-40min, and kept warm for about 15min to obtain a high dielectric fiber material BaTi2O5-G. The high dielectric fiber material BaTi2O5-G is added to the powder coating D100=35um and mixed and stirred for 20-30min, and a high dielectric powder coating composition is obtained by extrusion by a twin-screw machine, cooling and tableting, and powder classification.

[0041] Table 1 Ingredient ratio and performance of Examples 1 to 6 and Comparative Examples 1 to 4

[0042]

[0043] The description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A high dielectric fiber material, characterized in that: The high dielectric fiber material includes a fiber material BaTi2O5, an inorganic filler and a modifier, wherein the fiber material BaTi2O5 has a diameter of 80-200 nm and a length of 1-15 μm, and the inorganic filler includes the following components in weight percentage: SiO2: 40-70%, Al2O3: 10-25%, Fe2O3: 0.1-5%, CaO: 2-10%, MgO: 1-5%, B2O3: 5-15%, and the mass ratio of the fiber material to the inorganic filler is 1:1; The modifier is epoxy silane Modifier, the mass is 0.5-1.5% of the total mass of fiber material and inorganic filler; The high dielectric fiber material is prepared by melting the various components of the inorganic filler at 1000-1400°C, cooling, and then ball milling and classifying; stirring the fiber material and the inorganic filler, and uniformly adding an epoxy silane modifier to the stirred fiber material and the inorganic filler in a linear shape, stirring and heating to 100-130°C and keeping the temperature for a certain period of time to obtain the high dielectric fiber material.

2. The high dielectric fiber material according to claim 1, characterized in that: The purity of the BaTi2O5 is ≥99.5%.

3. A high dielectric powder coating composition, characterized in that: It comprises the high dielectric fiber material according to claim 1 or 2, and a powder coating, wherein the mass ratio of the high dielectric fiber material to the powder coating is 1.2-5:

10.

4. The high dielectric powder coating composition according to claim 3, characterized in that: The powder coating is powder coating interpon100.

5. The high dielectric powder coating composition according to claim 3, characterized in that: The particle size D100 of the powder coating is 35 um.

6. A method for preparing a high dielectric fiber material as claimed in claim 1 or 2, characterized in that: include: (1) diluting epoxy silane with an organic solvent and stirring at high speed to obtain an epoxy silane modifier; (2) Melting the various components of the inorganic filler at 900-1400°C, cooling, and then ball milling and classifying; (3) The fiber material and the inorganic filler are placed in a high-speed mixer, stirred at a low speed for a period of time, and then the high-speed stirring is turned on, and the epoxy silane modifier is added dropwise at a uniform speed, stirred and heated to 100-130°C and kept warm for a certain period of time to obtain a high dielectric fiber material.

7. The method for preparing a high dielectric fiber material according to claim 6, characterized in that: The low-speed stirring is stirring at a temperature of 60-70° C. and a rotation speed of 300-500 r / min for 10-15 min, and the high-speed stirring is stirring at a rotation speed of 800-1000 r / min for 15-40 min.

8. The method for preparing a high dielectric fiber material according to claim 6, characterized in that: In the step (1), when the organic solvent dilutes the epoxy silane, the mass ratio of the organic solvent to the epoxy silane is 2:

1.

9. A method for preparing a high dielectric powder coating composition, characterized in that: The high dielectric fiber material prepared according to claim 6 is added to the powder coating, mixed and stirred, extruded by a twin-screw machine, cooled and pressed into sheets, and powder classified to obtain a high dielectric powder coating composition, wherein the powder coating is powder coating interpon100, and its particle size D100=35um.

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