An ice template method for preparing a super-high dielectric constant composite material and a preparation method thereof

Abstract

The present application relates to a kind of ice template method prepared super high dielectric constant composite material and its preparation method.The super high dielectric constant composite material includes: the dense Ca 1‑ x La 2 / 3x TiO3 Ceramic skeleton and resin material filled in the ordered through-hole structure;Wherein 0≤x≤0.3.

Description

Technical Field

[0001] This invention relates to an ultra-high dielectric constant composite material, its preparation method and application, belonging to the field of high-frequency composite dielectric materials. Background Technology

[0002] High-frequency composite dielectric materials are made of ceramics and resins, combining the excellent thermal conductivity and dielectric properties of ceramics with the high reliability of resins. After being coated with copper foil on both sides, they are fabricated into printed circuit boards (PCBs) and widely used in aerospace, 5G base stations, automotive radar, and other communication fields, serving as a fundamental, common, and crucial material. According to microwave theory, device size is inversely proportional to the square root of the material's dielectric constant. Therefore, high-dielectric-constant microwave dielectric materials at high frequencies (~10GHz) are key to device miniaturization. Simultaneously, device miniaturization and integration inevitably lead to power concentration, generating more heat. To efficiently transfer heat to heat dissipation components, antenna devices place increasingly higher demands on the thermal conductivity of dielectric materials. Currently, research on high-dielectric-constant composite materials mainly focuses on high-dielectric-constant materials such as SrTiO3, BaTiO3, and CaCu3Ti4O3. 12 A ceramic or conductive filler is used to fill a resin matrix, and a dielectric-reinforcing phase is used to increase the dielectric constant of the polymer matrix.

[0003] Most studies employ a 0-3 type two-phase composite approach, focusing primarily on improving the intrinsic dielectric constant of the two phases. However, both are already close to their limits, resulting in a high-frequency dielectric constant below 25 and high dielectric loss. Furthermore, due to the dispersed distribution of the reinforcing phase, its thermal conductivity is also poor. Summary of the Invention

[0004] To address the above problems, this invention provides a composite material with ultra-high dielectric constant, its preparation method, and its application.

[0005] In a first aspect, the present invention provides a composite material with ultra-high dielectric constant, comprising: a dense Ca2 polymer having an ordered through-hole structure. 1-x La 2 / 3x TiO3 ceramic framework and resin material filled in the ordered through-hole structure; wherein 0≤x≤0.3.

[0006] Preferably, the dense Ca having an ordered through-hole structure 1-x La 2 / 3x The TiO3 ceramic framework has a porosity of 25%–85%, an ordered through-pore structure with a diameter of 10 μm–50 μm, and a relative density of 96%–98%.

[0007] Preferably, the resin material comprises at least one of silanolene resin, cyanate ester, epoxy resin, and polydimethylsilane; the content of the resin material is 25-85 vol%.

[0008] Secondly, the present invention provides a method for preparing an ultra-high dielectric constant composite material, comprising:

[0009] (1) Ca 1-x La 2 / 3x TiO3 powder is mixed with a template machine, and then a binder and dispersant are added to obtain a mixed slurry;

[0010] (2) The obtained mixed slurry was subjected to single-phase freezing and freeze-drying to obtain a ceramic green body skeleton;

[0011] (3) The obtained ceramic green body skeleton was sintered at 1300–1400℃ to obtain a dense Ca with an ordered through-pore structure. 1-x La 2 / 3x TiO3 ceramic framework;

[0012] (4) Dense Ca with ordered through-hole structure 1-x La 2 / 3x The TiO3 ceramic skeleton is placed in a resin material and then vacuum impregnated, followed by curing treatment to obtain the ultra-high dielectric constant composite material.

[0013] Preferably, the Ca 1-x La 2 / 3x The preparation method of TiO3 powder includes: mixing CaCO3 powder, La2O3 powder and TiO2 powder according to Ca... 1-x La 2 / 3x The TiO3 was weighed and mixed according to its stoichiometric ratio, and then calcined at 1100-1200℃ for 2-6 hours to obtain the product.

[0014] The template agent is selected from at least one of water, tert-butanol, and camphene, and the Ca... 1-x La 2 / 3x The volume ratio of TiO3 powder to template agent is 15-75%.

[0015] Preferably, the unidirectional freezing temperature is -196℃ to -20℃ and the time is 0.5 to 2 hours; the freeze-drying temperature is -40℃ to 50℃ and the time is 48 to 96 hours, and the atmosphere is a vacuum.

[0016] Preferably, the parameters for vacuum impregnation include: temperature of 80–150°C, air pressure of <100Pa, and time of 2–6 hours.

[0017] Preferably, the curing temperature is 140–210°C and the total time is 48–96 hours.

[0018] Beneficial effects:

[0019] 1. This invention can successfully prepare parallel structure composite materials by unidirectional freezing and resin impregnation, thereby significantly improving the dielectric constant;

[0020] 2. This invention can significantly improve the thermal conductivity along the Z-axis by forming a ceramic skeleton in the Z-axis direction;

[0021] 3. This invention uses a sintered, dense, high-performance CLT ceramic skeleton combined with a high-dielectric, low-loss PSAE composite to obtain a composite material with excellent high-frequency dielectric properties. Attached Figure Description

[0022] Figure 1 The cross-sectional microstructure of a composite material with a ceramic volume ratio of 80% is shown.

[0023] Figure 2 The cross-sectional microstructure of the composite material prepared in Example 10;

[0024] Figure 3 The cross-sectional microstructure of the composite material prepared in Comparative Example 4 is shown. Detailed Implementation

[0025] The present invention will be further illustrated by the following embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the present invention.

[0026] To address the technical problem that the dielectric constant of existing high-frequency composite materials cannot exceed 25, this invention proposes a method for preparing ultra-high dielectric constant composite materials through ice template + ultra-high temperature sintering + resin vacuum impregnation. Preferably, this invention provides a resin (e.g., silane-containing acetylenes) / CLT composite dielectric material with ultra-high dielectric constant, low dielectric loss, and high thermal conductivity, reinforced by a parallel structure.

[0027] Specifically, this invention first involves calcining a mixture of CaCO3, La2O3, and TiO2 in a stoichiometric ratio to obtain high-performance calcium-lanthanum-titanium ceramic powder. This powder is then mixed with a template agent and placed in a unidirectional cold source environment, causing the template agent to crystallize along a temperature gradient. During crystallization, ceramic particles are continuously displaced, forming a porous ceramic framework structure. The frozen sample is then freeze-dried, allowing the template agent to sublimate directly, leaving the ceramic framework. After sintering and densifying the ceramic, it is vacuum impregnated with PSAE resin to obtain a composite material with a parallel structure. This two-phase parallel composite material exhibits a dielectric constant significantly higher than that of the 0-3 type composite material.

[0028] The following exemplifies a method for preparing ultra-high dielectric constant composite materials.

[0029] CaCO3, La2O3, and TiO2 were mixed according to Ca... 1-x La 2 / 3x The stoichiometric ratio of TiO3 (0 < x < 0.3) was weighed and mixed to obtain a mixed powder. The mixing was performed by ball milling, with deionized water added as the milling medium, and the mixture was ball-milled at 300–500 rpm for 12–24 hours. Preferably, the ball-milled mixture was then dried. The drying temperature was 150°C, and the drying time was 10–15 hours. The mixed powder was then calcined at 1100–1200°C for 4 hours to obtain a calcined powder.

[0030] The calcined powder is subjected to a secondary ball milling process. The secondary ball milling process involves adding deionized water as the milling medium and milling at 300–500 rpm for 2 hours. Preferably, a secondary drying process is performed after the secondary ball milling at 150°C for 10–15 hours.

[0031] Calcined powder is mixed with a template agent (one or more of water, tert-butanol, and camphene) at a volume ratio of 15-75%, and then a binder and dispersant are added. The mixture is then ultrasonically dispersed to obtain a slurry. The binder can be at least one of PVA, PVB, and sodium methyl cellulose, and the amount added can be 1-3 wt% (preferably 2 wt%) of the calcined powder. The dispersant can be at least one of polyacrylic acid, stearamide, vinyl bis-stearamide, and tristearate, and the amount added can be 0.5-1.5 wt% (preferably 1%) of the calcined powder. The ultrasonic dispersion frequency can be 20 kHz to 200 kHz, and the time is 1 hour. Magnetic stirring is performed at a magnetic stirrer speed of 100-300 rpm for 5 hours. The resulting slurry is poured into a PTFE mold and then subjected to unidirectional freezing at a low temperature (-196℃ to -20℃) for 1 hour. The resulting block is then freeze-dried to sublimate the template agent, ultimately obtaining a ceramic green body skeleton.

[0032] The ceramic blank skeleton was sintered at 1300–1400℃. The sintered ceramic skeleton was then immersed in silyl acetylene (PSAE) and placed in a vacuum oven. After heating to 120℃, a negative pressure was applied with a vacuum degree below 100 Pa. The negative pressure was maintained for 4 hours and then returned to normal pressure.

[0033] The resin is cured, and after final cooling, a parallel structure composite material is obtained. The curing parameters include a temperature of 140–210°C and a total time of 12–14 hours. Preferably, the curing temperature is increased in stages, and the total time is controlled to not exceed 20 hours. For example, the curing is sequentially maintained at 140°C for 4 hours, 180°C for 4 hours, and 210°C for 4 hours.

[0034] In this invention, a composite material with a parallel structure was constructed using the ice template method and resin vacuum impregnation. This effectively suppressed the depolarization effect of ceramic powder in the resin matrix and the phonon scattering at the two-phase interface, achieving a dual enhancement of dielectric and thermal conductivity. The dielectric constant of the ultra-high dielectric constant composite material, tested using the resonant cavity method, reached 75.7, with a dielectric loss as low as 0.00094 (10 GHz). The thermal conductivity of the ultra-high dielectric constant composite material, tested using the laser scintillation method, reached 2.067 W·m. -1 ·K -1 .

[0035] The following examples further illustrate the present invention in detail. It should also be understood that the following examples are only for further explanation of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention are within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the appropriate range based on the description herein, and are not intended to be limited to the specific values ​​in the examples below.

[0036] Example 1

[0037] Step 1: Mix CaCO3, La2O3 and TiO2 according to the stoichiometric ratio of CaTiO3, add deionized water as the ball milling medium, ball mill for 24 hours, dry at 150℃, and then calcine the powder at 1200℃ for 4 hours.

[0038] Step 2: Add deionized water as the ball milling medium to the calcined powder, ball mill for 2 hours, and then dry at 150℃.

[0039] Step 3: Mix the above powder with template agent (preferably water) at a volume ratio of 15%, and add 2 wt% PVA and 1% ammonium polyacrylate. After ultrasonic dispersion for 1 hour, stir magnetically for 5 hours. Pour the resulting slurry into a PTFE mold and place it in a low temperature environment (-20°C) for unidirectional freezing for 1 hour. Then freeze-dry the resulting block to sublimate the template agent and finally obtain a ceramic skeleton.

[0040] Step 4: The obtained ceramic skeleton is sintered at 1400℃. The sintered ceramic skeleton is then immersed in silyl acetylene (PSAE) and placed in a vacuum oven. After heating to 120℃, negative pressure is applied with a vacuum degree of less than 100Pa. After holding under negative pressure for 4 hours, the pressure is restored to normal.

[0041] Step 5: Curing treatment of the resin: heat treatment at 140℃ for 4 hours, heat treatment at 180℃ for 4 hours, heat treatment at 210℃ for 4 hours, and finally cooling to obtain parallel structure composite material.

[0042] Example 2

[0043] The steps are the same as in Example 1, the ceramic component is CaTiO3, the ball milling time is 24h, the calcination temperature is 1200℃, the ceramic powder volume ratio is 30%, the freezing temperature is -20℃, and the skeleton sintering temperature is 1400℃.

[0044] Example 3

[0045] The steps are the same as in Example 1, but the ceramic component is Ca. 0.9 La 0.067 TiO3, ball milling time of 20h, calcination temperature of 1150℃, ceramic powder volume ratio of 45%, freezing temperature of -20℃, and skeleton sintering temperature of 1350℃.

[0046] Example 4

[0047] The steps are the same as in Example 1, but the ceramic component is Ca. 0.9 La 0.067 TiO3, ball milling time of 20h, calcination temperature of 1150℃, ceramic powder volume ratio of 50%, freezing temperature of -20℃, and skeleton sintering temperature of 1350℃.

[0048] Example 5

[0049] The steps are the same as in Example 1, but the ceramic component is Ca. 0.8 La 0.133 TiO3, ball milling time of 16h, calcination temperature of 1100℃, ceramic powder volume ratio of 60%, freezing temperature of -20℃, and skeleton sintering temperature of 1300℃.

[0050] Example 6

[0051] The steps are the same as in Example 1, but the ceramic component is Ca. 0.7 La 0.2 TiO3, ball milling time of 12h, calcination temperature of 1100℃, ceramic powder volume ratio of 75%, freezing temperature of -20℃, and skeleton sintering temperature of 1300℃.

[0052] Example 7

[0053] The steps are the same as in Example 1, the ceramic component is CaTiO3, the ball milling time is 24h, the calcination temperature is 1200℃, the ceramic powder volume ratio is 15%, the freezing temperature is -80℃, and the skeleton sintering temperature is 1400℃.

[0054] Example 8

[0055] The steps are the same as in Example 1, the ceramic component is CaTiO3, the ball milling time is 24h, the calcination temperature is 1200℃, the ceramic powder volume ratio is 30%, the freezing temperature is -80℃, and the skeleton sintering temperature is 1400℃.

[0056] Example 9

[0057] The steps are the same as in Example 1, but the ceramic component is Ca. 0.9 La 0.067 TiO3, ball milling time of 20h, calcination temperature of 1150℃, ceramic powder volume ratio of 45%, freezing temperature of -80℃, and skeleton sintering temperature of 1350℃.

[0058] Example 10

[0059] The steps are the same as in Example 1, but the ceramic component is Ca. 0.9 La 0.067 TiO3, ball milling time of 20h, calcination temperature of 1150℃, ceramic powder volume ratio of 50%, freezing temperature of -80℃, and skeleton sintering temperature of 1350℃.

[0060] Example 11

[0061] The steps are the same as in Example 1, but the ceramic component is Ca. 0.8 La 0.133 TiO3, ball milling time of 16h, calcination temperature of 1100℃, ceramic powder volume ratio of 60%, freezing temperature of -80℃, and skeleton sintering temperature of 1300℃.

[0062] Example 12

[0063] The steps are the same as in Example 1, but the ceramic component is Ca. 0.7 La 0.2 TiO3, ball milling time of 12h, calcination temperature of 1100℃, ceramic powder volume ratio of 75%, freezing temperature of -80℃, and skeleton sintering temperature of 1300℃.

[0064] Example 13

[0065] The steps are the same as in Example 1, the ceramic component is CaTiO3, the ball milling time is 24h, the calcination temperature is 1200℃, the ceramic powder volume ratio is 15%, the freezing temperature is -196℃, and the skeleton sintering temperature is 1400℃.

[0066] Example 14

[0067] The steps are the same as in Example 1, the ceramic component is CaTiO3, the ball milling time is 24h, the calcination temperature is 1200℃, the ceramic powder volume ratio is 30%, the freezing temperature is -196℃, and the skeleton sintering temperature is 1400℃.

[0068] Example 15

[0069] The steps are the same as in Example 1, but the ceramic component is Ca. 0.9 La 0.067 TiO3, ball milling time of 20h, calcination temperature of 1150℃, ceramic powder volume ratio of 45%, freezing temperature of -196℃, and skeleton sintering temperature of 1350℃.

[0070] Example 16

[0071] The steps are the same as in Example 1, but the ceramic component is Ca. 0.9 La 0.067 TiO3, ball milling time of 20h, calcination temperature of 1150℃, ceramic powder volume ratio of 50%, freezing temperature of -196℃, and skeleton sintering temperature of 1350℃.

[0072] Example 17

[0073] The steps are the same as in Example 1, but the ceramic component is Ca. 0.8 La 0.133 TiO3, ball milling time of 16h, calcination temperature of 1100℃, ceramic powder volume ratio of 60%, freezing temperature of -196℃, and skeleton sintering temperature of 1300℃.

[0074] Example 18

[0075] The steps are the same as in Example 1, but the ceramic component is Ca. 0.7 La 0.2 TiO3, ball milling time of 12h, calcination temperature of 1100℃, ceramic powder volume ratio of 75%, freezing temperature of -196℃, and skeleton sintering temperature of 1300℃.

[0076] Comparative Example 1

[0077] The steps are the same as in Example 1, the ceramic component is CaTiO3, the ball milling time is 24h, the calcination temperature is 1200℃, the ceramic powder volume ratio is 15%, the freezing temperature is -80℃, and the skeleton sintering temperature is 1200℃.

[0078] Comparative Example 2

[0079] The steps are the same as in Example 1, the ceramic component is CaTiO3, the ball milling time is 24h, the calcination temperature is 1200℃, the ceramic powder volume ratio is 30%, the freezing temperature is -80℃, and the skeleton sintering temperature is 1200℃.

[0080] Comparative Example 3

[0081] The steps are the same as in Example 1, but the ceramic component is Ca. 0.9 La 0.067TiO3, ball milling time of 20h, calcination temperature of 1200℃, ceramic powder volume ratio of 45%, freezing temperature of -80℃, and skeleton sintering temperature of 1150℃.

[0082] Comparative Example 4

[0083] The steps are the same as in Example 1, but the ceramic component is Ca. 0.9 La 0.067 TiO3, ball milling time of 20h, calcination temperature of 1200℃, ceramic powder volume ratio of 50%, freezing temperature of -80℃, and skeleton sintering temperature of 1150℃.

[0084] Comparative Example 5

[0085] (1) Arrange CaCO3, La2O3 and TiO2 according to Ca 1-x La 2 / 3x TiO3 (0 < x < 0.3) was mixed in stoichiometric ratio, and deionized water was added as the ball milling medium. After ball milling for 24 hours, the powder was dried at 150°C and then calcined at 1100-1200°C for 4 hours.

[0086] (2) Add the calcined powder to deionized water as the ball milling medium, ball mill for 2 hours, and then dry at 150°C.

[0087] (3) The obtained ceramic powder is granulated and then sintered at 1300-1400℃. The sintered ceramic powder is ball-milled three times for 4 hours and dried at 150℃ to obtain ceramic powder.

[0088] (4) Mix ceramic powder with silicone acetylene (PSAE) at a volume ratio of 15%, place it in a vacuum oven and heat it to 120°C. Then apply negative pressure with a vacuum degree of less than 100Pa. After holding the negative pressure for 4 hours, restore normal pressure.

[0089] (5) The resin is cured by holding at 140℃ for 4 hours, 180℃ for 4 hours, and 210℃ for 4 hours. After cooling, the 0-3 type composite material is obtained.

[0090] Comparative Example 6

[0091] The steps were the same as in Comparative Example 5. The chemical formula of the ceramic was CaTiO3. The ball milling time was 24 h. The calcination temperature was 1200 ℃. The sintering temperature was 1400 ℃. The ball milling time for the three times was 4 h. The ceramic volume ratio was 30%.

[0092] Comparative Example 7

[0093] The steps are the same as in Comparative Example 5, and the chemical formula of the ceramic is Ca. 0.9 La 0.067TiO3, ball milling time 20h, calcination temperature 1150℃, sintering temperature 1350℃, three ball milling times 3h, ceramic volume ratio 45%.

[0094] Comparative Example 8

[0095] The steps are the same as in Comparative Example 5, and the chemical formula of the ceramic is Ca. 0.9 La 0.067 TiO3, ball milling time 20h, calcination temperature 1150℃, sintering temperature 1350℃, three ball milling times 3h, ceramic volume ratio 50%.

[0096] Comparative Example 9

[0097] The steps are the same as in Comparative Example 5, and the chemical formula of the ceramic is Ca. 0.8 La 0.133 TiO3, ball milling time 16h, calcination temperature 1100℃, sintering temperature 1300℃, three ball milling times 2h, ceramic volume ratio 60%.

[0098] Table 1 lists the performance of the embodiments:

[0099]

[0100]

[0101] Table 2 shows dense CaO with ordered through-pore structure. 1-x La 2 / 3x Composition and parameters of TiO3 ceramic framework:

[0102]

[0103]

[0104] As shown in the examples, under the same cold source temperature, with the increase of the ceramic filling ratio, the dielectric constant and thermal conductivity of the composite material with parallel structure significantly increase while the dielectric loss significantly decreases. This is mainly because the ceramic itself has higher thermal conductivity and dielectric constant, as well as lower dielectric loss. Experiments have shown that if the ceramic filling ratio is further increased, it is impossible to construct a two-phase parallel structure, such as... Figure 1As shown. The solid content limit of the two-phase parallel structure constructed by the ice template method is around 75 vol%, therefore the volume ratio of the examples was set below 75 vol%. As the cold source temperature decreased from -20°C to -80°C, the supercooling of the system increased, and the freezing rate accelerated. Therefore, under the same ceramic volume ratio, the ceramic walls of the samples prepared in Examples 7-12 were thinner, but more numerous. This resulted in more two-phase interfaces, leading to an increase in dielectric constant and dielectric loss. At the same time, since thin walls are less conducive to phonon transmission, the thermal conductivity decreased slightly. Further reducing the cold source temperature to -196°C (liquid nitrogen) would lead to an excessively fast crystallization rate, making it impossible to form a uniform through-pore structure under high ceramic filling ratios. Therefore, the dielectric constant of the composite material under high filling ratios was actually lower than that of Example 12.

[0105] To illustrate the effect of dense sintering of the ceramic skeleton on the properties of the composite material in this invention, low-temperature sintered ceramic skeletons were added as comparative examples (Comparative Examples 1-4). The cross-sectional microstructures of the composite materials prepared in Example 10 and Comparative Example 4 are as follows: Figure 2 and Figure 3 As shown, the ceramic wall structure obtained by high-temperature sintering is dense, which is beneficial to improving the ceramic filling ratio and thermal conductivity. At low temperatures, the ceramic wall is not dense, and there are obvious gaps between the grains. This introduces a two-phase interface, leading to increased dielectric loss and interfacial thermal resistance. Furthermore, the ceramic filling ratio cannot exceed 50 vol%. The non-dense ceramic wall also reduces the mechanical properties of the composite material, with a significant decrease in flexural strength.

[0106] Using traditional 0-3 type composite materials as a comparative example, PSAE and CLT ceramics were directly mixed with the same ceramic filling ratio and their performance was tested. Experimental results show that in traditional 0-3 type composite materials, the ceramic powder is dispersed within a low-dielectric-constant resin matrix, producing a depolarization effect that significantly suppresses the dielectric constant of the composite material. Therefore, even with the same ceramic filling ratio, the dielectric constant of the composite material is much lower than that of the composite material with a parallel structure. Simultaneously, due to the large interfacial thermal resistance generated during phonon transmission by the dispersed ceramics, the thermal conductivity is also generally low.

[0107] In summary, the composite material with a parallel structure prepared in Example 12 significantly improves the dielectric constant to 75.72 by reducing the depolarization effect of the matrix on the ceramic, which is far higher than that of traditional 0-3 type composite materials. Due to the ultra-high ceramic filling ratio and dense ceramic wall structure, the dielectric loss of the composite material is only 0.00094. Simultaneously, due to the formation of thermal pathways, the thermal conductivity of the composite material is also increased to 2.067 W·m. -1 ·K -1 .

Claims

1. A method of preparing a super high dielectric constant composite material, characterized by, The ultra-high dielectric constant composite material includes: dense Ca with an ordered through-pore structure. 1-x La 2 / 3x The TiO3 ceramic framework and the resin material filling the ordered through-pore structure, wherein 0.2 ≤ x ≤ 0.3; the content of the resin material is 25–40 vol%; the dense Ca with the ordered through-pore structure 1-x La 2 / 3x The TiO3 ceramic framework has a porosity of 25-40%, an ordered through-pore structure with a diameter of 1.48 μm-46.28 μm, and a ceramic wall relative density of 96-98%. The preparation method includes: (1) Ca 1-x La 2 / 3x TiO3 powder is mixed with a template agent at a volume ratio of 60-75%, and then Ca is added. 1-x La 2 / 3x TiO3 powder with 2wt% binder and Ca 1-x La 2 / 3x A mixed slurry was obtained by adding 1 wt% TiO3 powder as a dispersant. (2) The obtained mixed slurry is subjected to unidirectional freezing and freeze-drying to obtain a ceramic green body skeleton; the temperature of the unidirectional freezing is -196℃ to -20℃; (3) sintering the obtained ceramic green body framework at 1300°C to obtain a dense Ca 1- x La 2 / 3x TiO3 ceramic framework; (4) Dense Ca with ordered through-hole structure 1-x La 2 / 3x The TiO3 ceramic skeleton is placed in a resin material and then vacuum impregnated, followed by curing treatment to obtain the ultra-high dielectric constant composite material.

2. The production method according to claim 1, characterized by, The resin material includes at least one of silanyl acetylenic resin, cyanate ester, epoxy resin and polydimethylsilane.

3. The preparation method according to claim 1, characterized in that, The Ca 1-x La 2 / 3x The preparation method of TiO3 powder includes: mixing CaCO3 powder, La2O3 powder and TiO2 powder according to Ca... 1-x La 2 / 3x The TiO3 was weighed and mixed according to its stoichiometric ratio, and then calcined at 1100-1200℃ for 2-6 hours to obtain the product. The template agent is selected from at least one of water, tert-butanol, and camphene.

4. The preparation method according to claim 1, characterized in that, The unidirectional freezing time is 0.5 to 2 hours; the freeze-drying temperature is -40℃ to 50℃, the time is 48 to 96 hours, and the atmosphere is vacuum.

5. The preparation method according to claim 1, characterized in that, The parameters for vacuum impregnation include: temperature of 80–150°C, air pressure of <100Pa, and time of 2–6 hours.

6. The method of claim 1, wherein, The curing process is carried out at a temperature of 140–210°C for a total time of 12–24 hours.

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