CN104877278A - Poly-n-butyl methacrylate/polyvinylidene fluoride vinyl compound dielectric film and preparation method thereof - Google Patents

Abstract

The invention discloses a poly-n-butyl methacrylate (PBMA)/polyvinylidene fluoride vinyl compound dielectric film. The film is formed by performing mixing and tape casting on florin-containing polymer and organic PBMA. The compound dielectric film is composed of, by mass percent, the components of 10%-30% of the organic PBMA and 70%-90% of the florin-containing polymer. The compound dielectric film is novel dielectric materials which are high in dielectric constant and low in dielectric loss. The compound dielectric film with the needed dielectric constant can be prepared by controlling the filler appending proportion. The compound dielectric film is simple in preparation technology, low in compound temperature and friendly to environment, and has a wide application prospect.

Description

A kind of poly n-butyl methacrylate/polyvinylidene fluoride based composite dielectric film and preparation method thereof

technical field

The invention belongs to the field of composite dielectric films, in particular to a polyn-butyl methacrylate (PBMA)/polyvinylidene fluoride-based composite dielectric film.

Background technique

Polymer-based dielectric materials with high dielectric constant and low dielectric loss are widely used because of their great potential in storing electrical energy, such as communication equipment, charge storage capacitor systems, artificial muscles, brakes, and aerospace military. . Traditional dielectric materials include inorganic ceramic materials and organic polymer materials. Common inorganic ceramic materials, such as barium titanate (BaTiO3), copper calcium titanate (CCTO), lead zirconate titanate (PZT), etc., have very high dielectric constants, but their preparation process is complex, brittle and dielectric The loss is large. Common organic polymer materials include polyethylene, polypropylene, polytrifluoroethylene, epoxy resin, etc. They have good flexibility, low dielectric loss, and are easy to process into films, but their dielectric constant is relatively low. A single dielectric material has been difficult to meet the needs of industrialization, so the preparation of polymer-based composite materials with high dielectric properties is of great significance. At present, polymer-based dielectric materials are mainly divided into the following three types: (1). Inorganic Ceramic materials: such as barium titanate (BaTiO ₃ ), which has a large capacitance and a dielectric constant as high as 6300, but the material has a high sintering temperature, complicated preparation process, brittleness, high processing requirements, and poor compatibility with polymers, so it is not easy to Film-forming, poor mechanical properties. (2). Conductive material: Graphene is added to PVDF as a filler to form a composite material. At 1000Hz, the dielectric constant of the composite material is more than three times that of the PVDF matrix, but the composite material will be affected by the percolation threshold, which is close to the percolation threshold. At the same time, the dielectric loss will be greatly improved, and the dielectric material will suddenly change into a conductive material, which will seriously affect its production and application. (3). Organic composite materials: such as polystyrene (PS), prepared PSAN film by solution coating method, the dielectric constant of the film is 4, the dielectric loss is 0.027, and the energy storage density reaches 6.8J/cm ³ , Good flexibility and low dielectric loss, but the dielectric constant is too small.

Contents of the invention

The main purpose of the present invention is to provide a poly(n-butyl methacrylate) (PBMA)/polyvinylidene fluoride based composite dielectric film. The composite film has good dielectric properties. The polyn-butyl methacrylate (PBMA)/polyvinylidene fluoride-based composite dielectric film is composed of PBMA and fluoropolymer. Its mass percentage consists of:

PBMA 10%-30%

Fluoropolymer 70%-90%

The poly-n-butyl methacrylate (PBMA)/polyvinylidene fluoride-based composite dielectric film is characterized in that the organic PBMA is a commercially available commodity;

The fluorine-containing polymer is polyvinylidene fluoride-trifluoroethylene copolymer [P(VDF-TrFE)], polyvinylidene fluoride-trifluoroethylene-fluorochloroethylene copolymer [P(VDF-TrFE-CFE)] One of.

Another object of the present invention is to provide a preparation method of poly-n-butyl methacrylate (PBMA)/polyvinylidene fluoride-based composite dielectric film:

1. After mixing PBMA, fluoropolymer and solvent N,N-dimethylformamide (DMF), ultrasonically stir and disperse evenly to form a stable sol; its mass percentage composition is:

PBMA 10%-30%

Fluoropolymer 70%-90%

The mass ratio of the total mass of organic PBMA and fluoropolymer to DMF is 1:7-10

2. Cast the sol prepared in step 1 on the mold at 80±1°C to form a film, dry for 18±1h, then undergo natural cooling, anneal at 120±1°C for 8±1h, and remove the residual solvent to obtain a film with a thickness of 110-150μm. Organic Filler/Polymer Matrix Composite Dielectric Films.

According to the above preparation method, within the range of the mass ratio of the organic PBMA, the mass ratio of the organic PBMA is adjusted, that is, composite dielectric films with different required dielectric constants are prepared.

The present invention has the following beneficial effects:

a. The organic PBMA filler overcomes many problems in the background technology. It has intermediate polarizability, exhibits high dielectric constant, low dielectric loss, good transparency, good flexibility, and has Higher mechanical properties.

b. The dielectric constant difference between the filler and the matrix is small, and it has good compatibility with the polymer substrate, so the composite dielectric film has good dielectric properties, and its dielectric loss does not increase significantly, still Maintained in a lower position, is a new type of high dielectric composite material.

c. The film can obviously change the dielectric properties of the material by adjusting the mass ratio of the organic filler PBMA, so as to prepare the required high dielectric constant film.

d. The preparation process of the film is simple, the compounding temperature is low, and it is environmentally friendly. The shape and size of the mold can be changed according to requirements, so that it is suitable for different electronic devices and energy storage materials.

The composite thin film of the present invention has relatively stable dielectric properties with changes in frequency, and no great mutation occurs. The dielectric constant of the composite film can be increased to about 45.

specific embodiment

Describe product and preparation method among the present invention by specific embodiment below. Unless otherwise specified, the technical means used in the present invention are methods known to those skilled in the art. In addition, the embodiments should be considered as illustrative rather than limiting the scope of the invention, the spirit and scope of which is defined only by the claims. For those skilled in the art, on the premise of not departing from the essence and scope of the present invention, various changes or modifications to the conditions such as ratios and solvents in these embodiments also belong to the protection category of the present invention.

The present invention will be further described below in conjunction with specific examples, but it is not meant to limit the protection scope of the present invention.

Example 1:

a. After mixing 0.0100g of organic PBMA, 0.1000g of polyvinylidene fluoride-trifluoroethylene copolymer [P(VDF-TrFE)] and 1.0005g of solvent DMF, ultrasonically stir and disperse evenly to form a stable sol. For: organic PBMA 10%, polymer 90%;

b. The sol prepared in step a was cast on a mold at 80°C to form a film, dried for 18 hours; then cooled naturally and annealed at 120°C for 8 hours to prepare a PBMA/P(VDF-TrFE) composite dielectric film. At 1000Hz, the dielectric constant can reach 16, the dielectric loss is 0.21, and the breakdown field strength is 322MV/m.

Example 2:

a. After mixing 0.0200g of organic PBMA, 0.1000g of polyvinylidene fluoride-trifluoroethylene copolymer [P(VDF-TrFE)] and 1.0005g of solvent DMF, ultrasonically stir and disperse evenly to form a stable sol. For: organic PBMA is 20%, polymer is 80%;

b. The sol prepared in step a was cast on a mold at 80°C to form a film, dried for 18 hours; then cooled naturally and annealed at 120°C for 8 hours to prepare a PBMA/P(VDF-TrFE) composite dielectric film. At 1000Hz, the dielectric constant can reach 23, the dielectric loss is 0.29, and the breakdown field strength is 243 MV/m.

Example 3:

a. After mixing 0.0300g of organic PBMA, 0.1000g of polyvinylidene fluoride-trifluoroethylene copolymer [P(VDF-TrFE)] and 1.0005g of solvent DMF, ultrasonically stir and disperse evenly to form a stable sol. For: organic PBMA is 30%, polymer is 70%;

b. The sol prepared in step a was cast on a mold at 80°C to form a film, dried for 18 hours; then cooled naturally and annealed at 120°C for 8 hours to prepare a PBMA/P(VDF-TrFE) composite dielectric film. At 1000Hz, the dielectric constant can reach 21, the dielectric loss is 0.30, and the breakdown field strength is 259MV/m.

Example 4:

This set of examples is comparative examples. After mixing 0.1000g of polyvinylidene fluoride-trifluoroethylene copolymer [P(VDF-TrFE)] and 1.0005g of solvent DMF, it was dispersed evenly by ultrasonic stirring to form a stable sol, and the prepared sol was cast on a mold at 80°C to form The film was dried for 18 hours; then cooled naturally and annealed at 120°C for 8 hours to prepare a P(VDF-TrFE) composite dielectric film. At 1000Hz, the dielectric constant can reach 15, the dielectric loss is 0.23, and the breakdown field strength is 300 MV/m.

Example 5:

a. After mixing 0.0100g of organic PBMA, 0.1000g of polyvinylidene fluoride-trifluoroethylene-chlorofluoroethylene copolymer [P(VDF-TrFE-CFE)] and 1.0005g of solvent DMF, ultrasonically stir and disperse evenly to form a stable Sol, the proportion of the ingredients consists of: organic PBMA is 10%, polymer is 90%;

b. The sol prepared in step a was cast on a mold at 80°C to form a film, dried for 18 hours; then cooled naturally and annealed at 120°C for 8 hours to prepare a PBMA/P(VDF-TrFE-CFE) composite dielectric film. At 1000Hz, the dielectric constant can reach 45, the dielectric loss is 2.5, and the breakdown field strength is 322 MV/m.

Embodiment 6:

a. After mixing 0.0200g of organic PBMA, 0.1000g of polyvinylidene fluoride-trifluoroethylene-chlorofluoroethylene copolymer [P(VDF-TrFE-CFE)] and 1.0005g of solvent DMF, ultrasonically stir and disperse evenly to form a stable Sol, the proportion of the ingredients is composed of: organic PBMA is 20%, polymer is 80%;

b. The sol prepared in step a was cast on a mold at 80°C to form a film, dried for 18 hours; then cooled naturally and annealed at 120°C for 8 hours to prepare a PBMA/P(VDF-TrFE-CFE) composite dielectric film. At 1000Hz, the dielectric constant can reach 34, the dielectric loss is 1.6, and the breakdown field strength is 203 MV/m.

Embodiment 7:

a. After mixing 0.0300g of organic PBMA, 0.1000g of polyvinylidene fluoride-trifluoroethylene-chlorofluoroethylene copolymer [P(VDF-TrFE-CFE)] and 1.0005g of solvent DMF, ultrasonically stir and disperse evenly to form a stable Sol, the proportion of the ingredients consists of: organic PBMA is 30%, polymer is 70%;

b. The sol prepared in step a was cast on a mold at 80°C to form a film, dried for 18 hours; then cooled naturally and annealed at 120°C for 8 hours to prepare a PBMA/P(VDF-TrFE-CFE) composite dielectric film. At 1000Hz, the dielectric constant can reach 40, the dielectric loss is 1.2, and the breakdown field strength is 202 MV/m.

Embodiment 8:

This set of examples is comparative examples. After mixing 0.1000g polyvinylidene fluoride-trifluoroethylene-chlorofluoroethylene copolymer [P(VDF-TrFE-CFE)] and 1.0005g solvent DMF, the ultrasonic stirring is dispersed evenly to form a stable sol, and the prepared sol is placed in the mold Cast at 80°C to form a film, dry for 18 hours; then cool naturally and anneal at 120°C for 8 hours to prepare a P(VDF-TrFE-CFE) composite dielectric film. At 1000Hz, the dielectric constant can reach 35, the dielectric loss is 2.0, and the breakdown field strength is 294 MV/m.

The embodiments of the present invention have been described in detail above. All embodiments are implemented on the premise of the technical solutions of the present invention, and detailed implementation methods and specific operating procedures are provided, but the protection scope of the present invention is not limited to the above-mentioned implementation. example.

Claims (5)

1. Vinalac 5920 (PBMA)/polyvinylidene fluoride compound dielectric film, it is characterized in that, described compound dielectric film is made up of fluoropolymer and organic filler PBMA, and its mass percent is: organic filler PBMA10%-30%, fluoropolymer 70%-90%.

2. Vinalac 5920 according to claim 1 (PBMA)/polyvinylidene fluoride compound dielectric film, is characterized in that, described organic PBMA is commercial goods.

3. Vinalac 5920 according to claim 1 (PBMA)/polyvinylidene fluoride compound dielectric film, it is characterized in that, described fluoropolymer is the one in polyvinylidene difluoride (PVDF)-trifluoro-ethylene [P (VDF-TrFE)], polyvinylidene difluoride (PVDF)-trifluoro-ethylene-chlorine vinyl fluoride [P (VDF-TrFE-CFE)] multipolymer.

4. a kind of Vinalac 5920 (PBMA)/polyvinylidene fluoride compound dielectric film according to claim 1, it is characterized in that, its preparation method is: by PBMA, after polyvinylidene difluoride (PVDF) based polyalcohol and solvent DMF mix, ultrasonic agitation is uniformly dispersed, form stable colloidal sol. by colloidal sol 80 DEG C of casting film-formings on mould of preparation, dry 18h; Again through naturally cooling, 120 DEG C of annealing 8h, namely prepare Vinalac 5920 (PBMA)/polyvinylidene fluoride compound dielectric film.

5. the preparation method of a kind of Vinalac 5920 (PBMA)/polyvinylidene fluoride compound dielectric film according to claim 4, is characterized in that, the mass ratio of described PBMA and fluoropolymer total mass and DMF is 1:7-10.