Pyroelectric polymer composite material and preparation method thereof

Abstract

The invention relates to the technical field of functional materials, in particular to a pyroelectric polymer composite material and a preparation method thereof. The composite material is composed of PVDF and modified BaTiO3, wherein the modified BaTiO3 is selected from one or more of BaTiO3 (at) SiO2 modified by copper phthalocyanine sebacate, BaTiO3 (at) SiO2 modified by copper phthalocyanine stearate, BaTiO3 (at) SiO2 modified by copper phthalocyanine octadecanedioate and BaTiO3 (at) SiO2 modified by copper phthalocyanine dopamine. The composite material of PVDF and BaTiO3 modified by different organic acids and (tetraamino phthalocyanine) copper can effectively combine the advantages of PVDF and BaTiO3 modified by different organic acids and (tetraamino phthalocyanine) copper, the high pyroelectric coefficient of BaTiO3 and the flexibility of PVDF are utilized, the performance of the composite material in pyroelectric application is improved, and the preparation method of the composite material is simple, low in cost, free of pollution and suitable for large-scale industrial production. In addition, the adopted materials are environment-friendly, and the requirement of sustainable development is met.

Description

Technical Field

[0001] The present invention relates to the technical field of functional materials, and in particular to a pyroelectric polymer composite material and a preparation method thereof. Background Art

[0002] Pyroelectric materials are a branch of piezoelectric materials and have been widely used in many fields such as infrared detectors and fire alarms. At present, pyroelectric materials mainly include crystalline materials, ceramic materials, polymer materials and ceramic polymer composites. Among these materials, crystalline materials are widely used because of their high pyroelectric coefficient, low dielectric constant and high detection sensitivity, but their cost is relatively high. The cost of ceramic materials is lower than that of crystalline materials, but there are certain difficulties in processing. In contrast, polymer materials have good flexibility, low cost, and are easy to make large-area uniform films. Among them, polyvinylidene fluoride (PVDF) is the most commonly used polymer pyroelectric material. PVDF is a crystalline polymer, and its crystal forms include α, β, γ, etc. Only β crystals have pyroelectric properties. When PVDF is cooled and crystallized after melting, it mainly forms α crystals, which do not have pyroelectric properties at this time. However, when α crystals are stretched at a temperature below their melting point, they are transformed into β crystals, thereby obtaining pyroelectric properties.

[0003] Take barium titanate (BT) as an example, although it belongs to ABO 3 Perovskite structure, but its crystal structure does not have a symmetry center. Under normal pressure, BT exhibits a structure that looks like a cubic crystal system, but its true structure is actually a tetragonal crystal system. As a common pyroelectric material, BT's pyroelectric coefficient is acceptable and can meet some application scenarios that do not require high pyroelectric performance. However, BT's Curie temperature is only 120°C, which limits its use to room temperature. When the temperature exceeds 100 degrees Celsius, BT's performance will drop significantly and it is no longer applicable. In addition, BT's relatively high dielectric loss and temperature coefficient also limit its scope of application to a certain extent. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the present invention provides a pyroelectric polymer composite material and a preparation method thereof.

[0005] A pyroelectric polymer composite material, the composite material is composed of PVDF and modified BaTiO 3 Composition, wherein the modified BaTiO 3 Selected from Sebacic Acid Phthalocyanine Copper Modified BaTiO 3 @SiO 2 , stearic acid copper phthalocyanine modified BaTiO 3 @SiO 2 , BaTiO modified by copper phthalocyanine octadecane3 @SiO 2 and dopamine copper phthalocyanine modified BaTiO 3 @SiO 2 One or more of .

[0006] Furthermore, the modified BaTiO 3 Selected from Sebacic Acid Phthalocyanine Copper Modified BaTiO 3 @SiO 2 .

[0007] Furthermore, the sebacic acid copper phthalocyanine modified BaTiO 3 @SiO 2 The mass ratio to PVDF is 1 to 10:100.

[0008] Furthermore, the sebacic acid copper phthalocyanine modified BaTiO 3 @SiO 2 The mass ratio of PVDF to 5:100.

[0009] Furthermore, the sebacic acid copper phthalocyanine modified BaTiO 3 @SiO 2 The preparation method is as follows: take 1gBaTiO 3 @SiO 2 The mixture was dispersed in 200 mL of 10 mM Tris-HCl buffer solution with a pH of about 8.5, and ultrasonicated for 30 min; then 500 mg of sebacic acid was added, the mixed solution was heated to 60 degrees Celsius, stirred at 60 degrees Celsius for 24 hours, and then 300 mg of (tetraaminophthalocyanine) copper was added, stirred at 60 degrees Celsius for 12 hours, and centrifuged to obtain a precipitate, and finally washed twice with water and anhydrous ethanol respectively, and dried in a vacuum freeze drying oven overnight to obtain sebacic acid phthalocyanine copper modified BaTiO 3 @SiO 2。

[0010] Furthermore, the BaTiO 3 @SiO 2 The preparation method is as follows: 1g BaTiO 3 The powder was added to 200 mL of ethanol and ultrasonically dispersed for 1 h. Then, 10 mL of deionized water and 12 mL of ammonia water were added. After stirring for 15 min, 2 mL of LTEOS was added dropwise at room temperature of 30 degrees Celsius while stirring. After the addition was completed, stirring was continued at room temperature of 30 degrees Celsius for 2 h. The precipitate was obtained by centrifugation, and the precipitate was washed twice with water and anhydrous ethanol respectively, and dried in a vacuum freeze drying oven overnight to obtain BaTiO 3 @SiO2.

[0011] The present invention also provides a method for preparing a pyroelectric polymer composite material, comprising the following steps:

[0012] Step S1: Add PVDF powder into DMF and stir at 75°C for 2 h;

[0013] Step S2: Weigh the modified BaTiO 3 @SiO 2 , added to DMF, ultrasonicated for 20 min; the modified BaTiO 3 Selected from Sebacic Acid Phthalocyanine Copper Modified BaTiO 3 @SiO 2 , stearic acid copper phthalocyanine modified BaTiO 3 @SiO 2 , BaTiO modified by copper phthalocyanine octadecane 3 @SiO 2 and dopamine copper phthalocyanine modified BaTiO 3 @SiO 2 One or more of;

[0014] Step S3: slowly adding the solution obtained in step S2 to the solution in step S1 while stirring, and then heating and stirring the obtained mixed solution for 3 hours;

[0015] Step S4: pour the mixed solution obtained in step S3 onto the casting substrate and dry it in a vacuum drying oven at 65° C. for 12 h;

[0016] Step S5: Sputter aluminum electrodes on both sides of the obtained thin film.

[0017] Furthermore, in step S3, the obtained mixed solution is heated to 60-85°C.

[0018] Furthermore, in step S3, the obtained mixed solution is heated to 70-80°C.

[0019] Furthermore, in step S3, the obtained mixed solution is heated to 75°C.

[0020] The present invention is achieved through the following technical solutions:

[0021] Compared with the prior art, the present invention has the following advantages and beneficial effects: PVDF, different organic acids and (tetraaminophthalocyanine) copper modified BaTiO 3 The composite material can effectively combine the advantages of both, using BaTiO 3 The high pyroelectric coefficient of PVDF and the flexibility of PVDF improve the performance of composite materials in pyroelectric applications. The preparation method of the composite material is simple, low-cost, and pollution-free, suitable for large-scale industrial production. In addition, the materials used are environmentally friendly and meet the requirements of sustainable development. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments. The illustrative embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0023] In the present invention, PVDF is polyvinylidene fluoride, which is a β-crystal form; sebacic acid CAS is: 111-20-6; DMF is N,N-dimethylformamide; octadecanedioic acid CAS number is 871-70-5; (tetraaminophthalocyanine) copper CAS number is 28632-30-6.

[0024] Example 1

[0025] A pyroelectric polymer composite material, comprising PVDF, copper phthalocyanine sebacic acid modified BaTiO 3 @SiO 2 composition.

[0026] Its preparation method is:

[0027] Step S1: 2.5 g of PVDF powder was added to 12 g of DMF and stirred at 75 °C for 2 h;

[0028] Step S2: Weigh 0.125 g of copper phthalocyanine sebacic acid modified BaTiO 3 @SiO 2 , added to 12 g of DMF and sonicated for 20 min;

[0029] Step S3: slowly adding the solution obtained in step S2 to the solution in step S1 while stirring, and then heating the obtained mixed solution to 75° C. and stirring for 3 h;

[0030] Step S4: pour the mixed solution obtained in step S3 onto the casting substrate and dry it in a vacuum drying oven at 65° C. for 12 h;

[0031] Step S5: Sputter aluminum electrodes on both sides of the obtained thin film.

[0032] The copper phthalocyanine sebacic acid modified BaTiO 3 @SiO 2 The preparation method is:

[0033] 1g BaTiO 3The powder was added to 200 mL of ethanol and ultrasonically dispersed for 1 h. Then, 10 mL of deionized water and 12 mL of ammonia water were added. After stirring for 15 min, 2 mL of TEOS was added dropwise at room temperature of 30 degrees Celsius while stirring. After the addition was completed, stirring was continued at room temperature of 30 degrees Celsius for 2 h. The precipitate was obtained by centrifugation, and the precipitate was washed twice with water and anhydrous ethanol respectively, and dried in a vacuum freeze drying oven overnight to obtain BaTiO 3 @SiO 2 ;

[0034] Take 1g BaTiO 3 @SiO 2 The mixture was dispersed in 200 mL of 10 mM Tris-HCl buffer solution with a pH of about 8.5, and ultrasonicated for 30 min; then 500 mg of sebacic acid was added, the mixed solution was heated to 60 degrees Celsius, stirred at 60 degrees Celsius for 24 hours, and then 300 mg of (tetraaminophthalocyanine) copper was added, stirred at 60 degrees Celsius for 12 hours, and centrifuged to obtain a precipitate, and finally washed twice with water and anhydrous ethanol, respectively, and dried in a vacuum freeze drying oven overnight to obtain sebacic acid phthalocyanine copper modified BaTiO 3 @SiO 2。

[0035] Example 2

[0036] A pyroelectric polymer composite material, comprising PVDF and stearic acid copper phthalocyanine modified BaTiO 3 @SiO 2 composition.

[0037] Its preparation method is:

[0038] Step S1: 2.5 g of PVDF powder was added to 12 g of DMF and stirred at 75 °C for 2 h;

[0039] Step S2: Weigh 0.125 g of stearic acid copper phthalocyanine modified BaTiO 3 @SiO 2 , added to 12 g of DMF and sonicated for 20 min;

[0040] Step S3: slowly adding the solution obtained in step S2 to the solution in step S1 while stirring, and then heating the obtained mixed solution to 75° C. and stirring for 3 h;

[0041] Step S4: pour the mixed solution obtained in step S3 onto the casting substrate and dry it in a vacuum drying oven at 65° C. for 12 h;

[0042] Step S5: Sputter aluminum electrodes on both sides of the obtained thin film.

[0043] The stearic acid copper phthalocyanine modified BaTiO 3 @SiO 2 The preparation method is:

[0044] 1g BaTiO 3 The powder was added to 200 mL of ethanol and ultrasonically dispersed for 1 h. Then, 10 mL of deionized water and 12 mL of ammonia water were added. After stirring for 15 min, 2 mL of TEOS was added dropwise at room temperature of 30 degrees Celsius while stirring. After the addition was completed, stirring was continued at room temperature of 30 degrees Celsius for 2 h. The precipitate was obtained by centrifugation, and the precipitate was washed twice with water and anhydrous ethanol respectively, and dried in a vacuum freeze drying oven overnight to obtain BaTiO 3 @SiO 2 ;

[0045] Take 1g BaTiO 3 @SiO 2 The mixture was dispersed in 200 mL of 10 mM Tris-HCl buffer solution with a pH of about 8.5, and ultrasonicated for 30 min. Then, 500 mg of stearic acid was added, and the mixed solution was heated to 60 degrees Celsius and stirred at 60 degrees Celsius for 24 hours. Then, 300 mg of (tetraaminophthalocyanine) copper was added, and stirred at 60 degrees Celsius for 12 hours. The precipitate was obtained by centrifugation, and finally washed twice with water and anhydrous ethanol, respectively, and dried in a vacuum freeze drying oven overnight to obtain stearic acid phthalocyanine copper modified BaTiO 3 @SiO 2。

[0046] Example 3

[0047] A pyroelectric polymer composite material, comprising PVDF, octadecane diacid copper phthalocyanine modified BaTiO 3 @SiO 2 composition.

[0048] Its preparation method is:

[0049] Step S1: 2.5 g of PVDF powder was added to 12 g of DMF and stirred at 75 °C for 2 h;

[0050] Step S2: Weigh 0.125 g of BaTiO modified with copper phthalocyanine octadecane dioate 3 @SiO 2 , added to 12 g of DMF and sonicated for 20 min;

[0051] Step S3: slowly adding the solution obtained in step S2 to the solution in step S1 while stirring, and then heating the obtained mixed solution to 75° C. and stirring for 3 h;

[0052] Step S4: pour the mixed solution obtained in step S3 onto the casting substrate and dry it in a vacuum drying oven at 65° C. for 12 h;

[0053] Step S5: Sputter aluminum electrodes on both sides of the obtained thin film.

[0054] The stearic acid copper phthalocyanine modified BaTiO 3 @SiO 2 The preparation method is:

[0055] 1g BaTiO 3 The powder was added to 200 mL of ethanol and ultrasonically dispersed for 1 h. Then, 10 mL of deionized water and 12 mL of ammonia water were added. After stirring for 15 min, 2 mL of TEOS was added dropwise at room temperature of 30 degrees Celsius while stirring. After the addition was completed, stirring was continued at room temperature of 30 degrees Celsius for 2 h. The precipitate was obtained by centrifugation, and the precipitate was washed twice with water and anhydrous ethanol respectively, and dried in a vacuum freeze drying oven overnight to obtain BaTiO 3 @SiO 2 ;

[0056] Take 1g BaTiO 3 @SiO 2 The mixture was dispersed in 200 mL of 10 mM Tris-HCl buffer solution with a pH of about 8.5, and ultrasonicated for 30 min; then 500 mg of octadecane dioic acid was added, the mixed solution was heated to 60 degrees Celsius, stirred at 60 degrees Celsius for 24 hours, and then 300 mg of (tetraaminophthalocyanine) copper was added, stirred at 60 degrees Celsius for 12 hours, and centrifuged to obtain a precipitate, and finally washed twice with water and anhydrous ethanol, respectively, and dried in a vacuum freeze drying oven overnight to obtain octadecane dioic acid phthalocyanine copper modified BaTiO 3 @SiO 2。

[0057] Example 4

[0058] A pyroelectric polymer composite material, comprising PVDF and dopamine copper phthalocyanine modified BaTiO 3 @SiO 2 composition.

[0059] Its preparation method is:

[0060] Step S1: 2.5 g of PVDF powder was added to 12 g of DMF and stirred at 75 °C for 2 h;

[0061] Step S2: Weigh 0.125 g of dopamine copper phthalocyanine modified BaTiO 3 @SiO 2 , added to 12 g of DMF and sonicated for 20 min;

[0062] Step S3: slowly adding the solution obtained in step S2 to the solution in step S1 while stirring, and then heating the obtained mixed solution to 75° C. and stirring for 3 h;

[0063] Step S4: pour the mixed solution obtained in step S3 onto the casting substrate and dry it in a vacuum drying oven at 65° C. for 12 h;

[0064] Step S5: Sputter aluminum electrodes on both sides of the obtained thin film.

[0065] The dopamine copper phthalocyanine modified BaTiO 3 @SiO 2 The preparation method is:

[0066] 1g BaTiO 3 The powder was added to 200 mL of ethanol and ultrasonically dispersed for 1 h. Then, 10 mL of deionized water and 12 mL of ammonia water were added. After stirring for 15 min, 2 mL of TEOS was added dropwise at room temperature of 30 degrees Celsius while stirring. After the addition was completed, stirring was continued at room temperature of 30 degrees Celsius for 2 h. The precipitate was obtained by centrifugation, and the precipitate was washed twice with water and anhydrous ethanol respectively, and dried in a vacuum freeze drying oven overnight to obtain BaTiO 3 @SiO 2 ;

[0067] Take 1g BaTiO 3 @SiO 2 The mixture was dispersed in 200 mL of 10 mM Tris-HCl buffer solution with a pH of about 8.5, and ultrasonicated for 30 min; then 500 mg of dopamine was added, the mixed solution was heated to 60 degrees Celsius, stirred at 60 degrees Celsius for 24 hours, and then 300 mg of (tetraaminophthalocyanine) copper was added, stirred at 60 degrees Celsius for 12 hours, and centrifuged to obtain a precipitate, and finally washed twice with water and anhydrous ethanol respectively, and dried in a vacuum freeze drying oven overnight to obtain dopamine phthalocyanine copper modified BaTiO 3 @SiO 2。

[0068] The pyroelectric coefficient is tested according to the method specified in GB / T11297.8-2015, and the pyroelectric coefficient at 25°C is calculated.

[0069] <![CDATA[Pyroelectric coefficient μC / m 2 K]]> Example 1 197 Example 2 136 Example 3 142 Example 4 135

[0070] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A pyroelectric polymer composite material, characterized in that: The composite material consists of PVDF and modified BaTiO3, wherein the modified BaTiO3 is selected from one or more of sebacic acid copper phthalocyanine modified BaTiO3@SiO2, stearic acid copper phthalocyanine modified BaTiO3@SiO2, octadecanedioic acid copper phthalocyanine modified BaTiO3@SiO2 and dopamine copper phthalocyanine modified BaTiO3@SiO2.

2. The pyroelectric polymer composite material according to claim 1, characterized in that: The modified BaTiO3 is selected from sebacic acid phthalocyanine copper modified BaTiO3@SiO2.

3. The pyroelectric polymer composite material according to claim 2, characterized in that: The mass ratio of the sebacic acid copper phthalocyanine modified BaTiO3@SiO2 to PVDF is 1 to 10:

100.

4. The pyroelectric polymer composite material according to claim 3, characterized in that: The mass ratio of the sebacic acid copper phthalocyanine modified BaTiO3@SiO2 to PVDF is 5:

100.

5. The pyroelectric polymer composite material according to claim 2, characterized in that: The preparation method of the copper phthalocyanine sebacic acid modified BaTiO3@SiO2 is as follows: 1g of BaTiO3@SiO2 is dispersed in 200mL of 10mM Tris-HCl buffer solution with a pH of about 8.5, and ultrasonicated for 30 minutes; then 500mg of sebacic acid is added, the mixed solution is heated to 60 degrees Celsius, stirred at 60 degrees Celsius for 24 hours, and then 300mg of (tetraaminophthalocyanine) copper is added, stirred at 60 degrees Celsius for 12 hours, centrifuged to obtain a precipitate, and finally washed twice with water and anhydrous ethanol respectively, and dried in a vacuum freeze drying oven overnight to obtain the copper phthalocyanine sebacic acid modified BaTiO3@SiO2.

6. The pyroelectric polymer composite material according to claim 5, characterized in that: The preparation method of BaTiO3@SiO2 is as follows: 1g BaTiO3 powder is added to 200mL ethanol, and ultrasonically dispersed for 1h; then 10mL deionized water and 12mL ammonia water are added; after stirring for 15min, 2mL LTEOS is added dropwise while stirring at room temperature of 30 degrees Celsius, and after the addition is completed, stirring is continued at room temperature of 30 degrees Celsius for 2h; a precipitate is obtained by centrifugation, the precipitate is washed twice with water and anhydrous ethanol respectively, and dried in a vacuum freeze drying oven overnight to obtain BaTiO3@SiO2.

7. The method for preparing a pyroelectric polymer composite material according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step S1: Add PVDF powder into DMF and stir at 75°C for 2 h; Step S2: Weigh the modified BaTiO3@SiO2, add it to DMF, and sonicate for 20 minutes; the modified BaTiO3 is selected from one or more of BaTiO3@SiO2 modified with sebacic acid copper phthalocyanine, BaTiO3@SiO2 modified with stearic acid copper phthalocyanine, BaTiO3@SiO2 modified with octadecane dioic acid copper phthalocyanine, and BaTiO3@SiO2 modified with dopamine copper phthalocyanine; Step S3: slowly adding the solution obtained in step S2 to the solution in step S1 while stirring, and then heating and stirring the obtained mixed solution for 3 hours; Step S4: pour the mixed solution obtained in step S3 onto the casting substrate and dry it in a vacuum drying oven at 65° C. for 12 h; Step S5: Sputter aluminum electrodes on both sides of the obtained thin film.

8. The method for preparing the pyroelectric polymer composite material according to claim 7, characterized in that: In the step S3, the obtained mixed solution is heated to 60-85°C.

9. The method for preparing the pyroelectric polymer composite material according to claim 8, characterized in that: In the step S3, the obtained mixed solution is heated to 70-80°C.

10. The method for preparing the pyroelectric polymer composite material according to claim 9, characterized in that: In step S3, the obtained mixed solution is heated to 75°C.