DE202021106863U1 - A system for developing improved ferroelectric polymer dielectrics from PVDF-metal/PVDF-ceramic composites/nanocomposites - Google Patents

Abstract

A system for developing improved polymer-based ferroelectric polymer dielectrics from PVDF-metal/PVDF-ceramic composites, the system comprising:
an agate mortar and pestle for mixing a mixture of ferroelectric polymer and metallic/ceramic fillers for about 2 hours; and
discloses a hydraulic press for pressing mixture powder poured into a die to produce a plurality of samples of the powder mixture in the form of pellets using a cold pressing process at room temperature to develop polymer dielectrics.

Description

FIELD OF THE INVENTION

The present disclosure relates to a system for producing polymer nanocomposites from PVDF with metallic micron/nano fillers and nano-ceramic fillers, e.g. with nano-nickel and n-BaTiO3, as polymer dielectrics for use in electronic packages, electronic components made with such dielectric materials, and for dielectric materials in capacitor applications.

BACKGROUND OF THE INVENTION

Polymeric dielectrics have been researched for 20 years for their development as energy storage materials for capacitors to replace the traditional ceramics such as BaTiO3, PMN-PT, PZT, etc., which contain lead (Pb) as a toxicant, have design problems, longer processing and higher Requiring energy consumption in their synthesis, etc. In the development of these polymer dielectrics, PVDF-based ferroelectric polymer dielectrics have been researched in order to obtain superior polymer dielectrics. But this polymer PVDF loses its spherulites through the traditional hot forming process, reducing the interfaces between the natural spherulites present in the polymer PVDF, reducing their efficiency as better polymer dielectrics.

Today, polymer-based composites are of great importance in the field of polymer dielectrics as energy storage materials, since they can overcome the disadvantages of dielectric/ferroelectric ceramics. Insulating ferroelectric polymers reinforced with conductive fillers/ferroelectric ceramic fillers can achieve high dielectric constant with low loss tangent. The development of various polymer composites for energy storage and other applications can be gleaned from the various prior art reports.

In a prior art solution ( W02016142848A1 ) a polymer nanocomposite, a method and its applications are disclosed. The disclosure describes the development of methods for developing polymer-ceramic composites for high-dielectric-constant applications, where the non-ferroelectric polymers, e.g. B. epoxy, and ceramic fillers, z. B. laboratory lead magnesium niobate titanate (PMN-PT), were used to find materials with a dielectric constant of ~150.

In another prior art solution ( US9556321B2 ) High-dielectric-constant composites and methods of manufacture are disclosed. The method describes the development of high dielectric constant, high dielectric strength polymer composites composed of barium titanate/barium strontium titanate (BST) with the polymer [formed from a trialkoxysilane selected from a group consisting of triethoxyvinylsilane, vinyltrimethoxysilane and aminopropyltriethoxysilane]. a dielectric constant in the order of 100-550 for operation in high power, high energy density systems.

In another prior art solution ( US8729182B2 ) nanocomposites with high energy density and corresponding manufacturing processes are disclosed. The process develops high-energy-density polymer nanocomposites made from BaTiO3 and TiO2 with non-ferroelectric polymers, e.g. B. isotactic polypropylene, by in situ polymerization.

In another prior art solution ( US20130317170A1 ) a nanocomposite of metallic aluminum nanoparticles and polymers for energy storage is disclosed. The nanoparticle composition includes a substrate comprising aluminum nanoparticles, an Al2O3 component coating the aluminum nanoparticles, and a metallocene catalyst component associated with the Al2O3 component; and a polyolefin component bonded to the substrate.

In another prior art solution ( US20110315914A1 ) a nanocomposite with high dielectric constant is disclosed. The disclosure describes high-dielectric-constant polymer nanocomposites containing at least one ferroelectric filler and at least one non-ferroelectric filler, e.g. B. barium titanate nanocrystals and zinc oxide nanorods and/or nanowires dispersed in a non-ferroelectric polymer, e.g. B. an epoxy matrix.

In another prior art solution ( US7609504B2 ) discloses a high-dielectric-constant metal-ceramic-polymer composite material and a method of making an embedded capacitor using the same. The patent describes the development of a high-dielectric-constant composite material composed of ferroelectric ceramics, e.g. B. BaTiO ₃ , PbTiO ₃ , CaTiO ₃ , SrTiO ₃ , PMN, PMN-PT, PZT, PZT-PT with metal particles, z. B. Cu, Ni, Ag, Ag, etc. z. B. Cu, Ni, Ag, Al, Zn, Co, Fe, Cr, Mn, on the order of microns in one non-ferroelectric polymer of polymethyl methacrylate (PMMA)/epoxy resins/bisphenol. The dielectric constant obtained was of the order of 100 with a loss tangent of 0.6.

In another prior art solution ( US9732175B2 ) Ceramic-polymer nanocomposites are disclosed. The patent describes a method for producing a polymer-ceramic nanocomposite by a complex in situ polymerisation process for ferroelectric polymers (tetrafluoroethylene, hexafluoropropylene or vinylidene fluoride).

In another prior art solution ( US9011627B2 ) discloses a method for producing capacitors and energy stores with a high dielectric constant and low leakage current. The patent describes a process for preparing a high-k dielectric material with low leakage current from non-ferroelectric polymers for capacitor and energy storage devices.

In view of the foregoing, it is clear that a system is needed to develop improved ferroelectric polymer dielectrics based on PVDF-metal/PVDF-ceramic composites/nanocomposites.

SUMMARY OF THE INVENTION

The present disclosure aims to provide a system for developing a high-k and low-leakage dielectric material composed of ferroelectric polymers for capacitors and energy storage devices.

In one embodiment, a system for developing improved polymer-based ferroelectric polymer dielectrics from PVDF-metal/PVDF-ceramic composites is disclosed. The system includes an agate mortar and pestle for mixing a mixture of ferroelectric polymer and metallic/ceramic fillers for about 2 hours. The system further includes a hydraulic press for compressing the mixture powder poured into a die to produce a plurality of samples of the powder mixture in the form of pellets using a room temperature cold pressing process to develop polymer dielectrics.

In another embodiment, the powder mixture is poured through a die/punch and pressed at a pressure of 10 MPa - 30 MPa by the hydraulic press for 10 minutes at room temperature to obtain the plurality of samples in the form of pellets with a diameter of 12 mm and a thickness of about 1 mm - 2 mm.

In another embodiment, the cold pressing process keeps the existing spherulites of the ferroelectric polymers, e.g. PVDF and also in their composites, alive, effectively creating higher charge storage at these natural spherulitic interfaces while sustaining the occurrence of polymer spherulite loss from PVDF conventional hot pressing is demonstrated, suggesting that hot pressing is less effective than the currently reported method.

In another embodiment, the effective role of the polymer spherulites of ferroelectric polymers in storing electrical charges was demonstrated through the use of a ferroelectric polymer [polyvinylidene fluoride (PVDF)] and a non-ferroelectric polymer [low density polyethylene (LDPE)].

In another embodiment, high purity (99.9%) metallic/ceramic fillers are selected, e.g. B. Metal powders including nickel (Ni) with an initial particle size of ~10 µm - 20 µm and nanocrystalline Ni (n-Ni) with a particle size of ~20 nm - 30 nm and the nano-BaTiO3 (n-BaTiO3) ceramic fillers with a particle size < 100 nm for the production of polymer nanocomposites.

In another embodiment, the PVDF/n-Ni polymer nanocomposites and the PVDF/n-BaTiO 3 polymer nanocomposites are processed such that the samples have a higher degree of homogeneity and are stabilized with respect to temperatures.

In another embodiment, processing to block a continuous network formation of the conductive/ceramic fillers is demonstrated to produce a blockage of the continuous conductive paths of the conductive fillers or the continuous network of ceramic fillers in the base polymer matrix.

An objective of the present disclosure is the fabrication of high performance polymer dielectrics from polymer nanocomposites composed of ferroelectric polymer PVDF and metal nanofillers/ferroelectric ceramic nanofillers.

Another object of the present disclosure is to keep the existing spherulites of the ferroelectric polymers and their composites alive and allow for higher charge storage at these natural interfaces.

Another object of the present invention is to provide a rapid and inexpensive system for the development of improved ferroelectric polymer dielectrics based on PVDF-metal/PVDF-ceramic composites.

In order to further clarify the advantages and features of the present disclosure, a more detailed description of the invention is provided by reference to specific embodiments that are illustrated in the accompanying figures. It is understood that these figures represent only typical embodiments of the invention and therefore should not be considered as limiting the scope of the invention. The invention will be described and illustrated with additional specificity and detail with the accompanying figures.

character list

• 1 zeigt ein Blockdiagramm eines Systems zur Entwicklung verbesserter ferroelektrischer Polymer-Dielektrika auf Polymerbasis aus PVDF-Metall/PVDF-Keramik-Verbundwerkstoffen/Nanokompositen gemäß einer Ausführungsform der vorliegenden Offenbarung;
• 2 zeigt einen Vergleich von FESEM-Bildern von kaltgepresstem reinem PVDF, die Sphärolithe und die ausgezeichneten Grenzflächen zwischen ihnen zeigen, mit heißgepresstem PVDF, dass keine Sphärolithe und Grenzflächen aufweist, gemäß einer Ausführungsform der vorliegenden Offenbarung;
• 3 zeigt einen Vergleich von FESEM-Bildern von kaltgepresstem reinem LDPE und heißgeformtem LDPE, die das Nichtvorhandensein von Sphärolithen und Grenzflächen gemäß einer Ausführungsform der vorliegenden Offenbarung zeigen;
• 4 zeigt einen Vergleich des dielektrischen Verhaltens von reinem PVDF, das durch Kalt- und Heißpressen hergestellt wurde und im Einschub: Sphärolithe aus kaltgepresstem PVDF gemäß einer Ausführungsform der vorliegenden Offenbarung;
• 5 zeigt FESEM-Bilder von kaltgepressten PVDF/Nanonickel-Verbundwerkstoffen gemäß einer Ausführungsform der vorliegenden Offenbarung;
• 6 zeigt FESEM-Bilder von kaltgepresstem reinem PVDF und PVDF/n-BaTi03-Nanokompositen in Übereinstimmung mit einer Ausführungsform der vorliegenden Offenbarung;
• 7 zeigt die Veränderung der relativen Kristallinität von reinem PVDF (a) Röntgendiffraktometrische Daten von kaltgepressten und heißgepressten Proben, und im Einschub: Größere Ansicht, die die Veränderung der kristallinen Peakfläche zeigt (b) FTIR-Daten von Kalt- und Heißpressproben in Übereinstimmung mit einer Ausführungsform der vorliegenden Offenbarung;
• 8 zeigt Differential-Scanning-Kalorimetrie (DSC) Diagramme der kaltgepressten PVDF/n-Ni-Verbundwerkstoffe, die ihre Stabilität mit steigender Temperatur in Übereinstimmung mit einer Ausführungsform der vorliegenden Offenbarung zeigen;
• 9 zeigt mikroskopische Aufnahmen von kaltgepresstem reinem PVDF und PVDF/µ-Ni-Verbundwerkstoffen mit unterschiedlichen f_con Werten gemäß einer Ausführungsform der vorliegenden Offenbarung;
• 10 zeigt mikroskopische Aufnahmen von heißgeformtem reinem PVDF und PVDF/µ-Ni-Verbundwerkstoffen mit unterschiedlichem f_con gemäß einer Ausführungsform der vorliegenden Offenbarung;
• 11 zeigt mikroskopische Aufnahmen von kaltgepresstem reinem PVDF und PVDF/n-Ni-Verbundwerkstoffen mit unterschiedlichen f_con Werten gemäß einer Ausführungsform der vorliegenden Offenbarung; und
• 12 zeigt mikroskopische Aufnahmen der Verbundstoffe, die verschiedenen f_con von heißgeformten PVDF/n-Ni-Verbundstoffen gemäß einer Ausführungsform der vorliegenden Offenbarung entsprechen.

These and other features, aspects, and advantages of the present disclosure will be better understood when the following detailed description is read with reference to the accompanying figures, in which like characters represent like parts throughout the figures, wherein:

• 1 Figure 12 shows a block diagram of a system for developing improved polymer-based ferroelectric polymer-dielectrics from PVDF-metal/PVDF-ceramic composites/nanocomposites according to an embodiment of the present disclosure;
• 2 12 shows a comparison of FESEM images of cold-pressed virgin PVDF showing spherulites and the excellent interfaces between them, with hot-pressed PVDF showing no spherulites and interfaces, according to an embodiment of the present disclosure;
• 3 12 shows a comparison of FESEM images of cold-pressed virgin LDPE and hot-formed LDPE showing the absence of spherulites and interfaces according to an embodiment of the present disclosure;
• 4 12 shows a comparison of the dielectric behavior of virgin PVDF prepared by cold and hot pressing and in inset: spherulites from cold pressed PVDF according to an embodiment of the present disclosure;
• 5 12 shows FESEM images of cold-pressed PVDF/nano-nickel composites according to an embodiment of the present disclosure;
• 6 12 shows FESEM images of cold-pressed bare PVDF and PVDF/n-BaTiO 3 nanocomposites, in accordance with an embodiment of the present disclosure;
• 7 shows the change in relative crystallinity of pure PVDF (a) X-ray diffraction data from cold-pressed and hot-pressed samples, and in the inset: larger view showing the change in crystalline peak area (b) FTIR data from cold- and hot-pressed samples in accordance with one embodiment the present disclosure;
• 8th Figure 12 shows differential scanning calorimetry (DSC) plots of cold-pressed PVDF/n-Ni composites showing their stability with increasing temperature, in accordance with an embodiment of the present disclosure;
• 9 12 shows photomicrographs of cold-pressed virgin PVDF and PVDF/μ-Ni composites with different f _con values according to an embodiment of the present disclosure;
• 10 12 shows photomicrographs of hot-formed virgin PVDF and PVDF/µ-Ni composites with different f _con according to an embodiment of the present disclosure;
• 11 12 shows photomicrographs of cold-pressed virgin PVDF and PVDF/n-Ni composites with different f _con values according to an embodiment of the present disclosure; and
• 12 12 shows photomicrographs of composites corresponding to different f _con of hot-formed PVDF/n-Ni composites according to an embodiment of the present disclosure.

Those skilled in the art will understand that the elements in the figures are presented for simplicity and are not necessarily drawn to scale. For example, the flow charts illustrate the method of key steps to enhance understanding of aspects of the present disclosure. Furthermore, one or more components of the device may be represented in the figures by conventional symbols, and the figures only show the specific details relevant to an understanding of the embodiments of the present disclosure to avoid deleting the figures with details to overload, which are easily recognizable to those skilled in the art familiar with the present description.

DETAILED DESCRIPTION:

For the purposes of promoting an understanding of the invention, reference will now be made to the embodiment illustrated in the figures and specific language will be used to describe the same. It should be understood, however, that no limitation on the scope of the invention is intended, and such alterations and further modifications to the illustrated system and such further applications of the principles of the invention set forth therein are contemplated as would occur to those skilled in the art invention would normally come to mind.

Those skilled in the art will understand that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not to be taken as limiting.

When this specification refers to "an aspect," "another aspect," or the like, it means that a particular feature, structure, or characteristic described in connection with the embodiment is present in at least one embodiment included in the present disclosure. Therefore, the phrases "in one embodiment," "in another embodiment," and similar phrases throughout this specification may or may not all refer to the same embodiment.

The terms "comprises," "including," or other variations thereof are intended to cover non-exclusive inclusion such that a method or method that includes a list of steps includes not only those steps, but may also include other steps that are not expressly stated or pertaining to any such process or method. Likewise, any device or subsystem or element or structure or component preceded by "comprises...a" does not, without further limitation, exclude the existence of other devices or other subsystem or other element or other structure or other component or additional device or additional subsystems or additional elements or additional structures or additional components.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art to which this invention pertains. The system, methods, and examples provided herein are for purposes of illustration only and are not intended to be limiting.

Embodiments of the present disclosure are described in detail below with reference to the attached figures.

1 10 shows a block diagram of a system for developing improved ferroelectric polymer dielectrics based on PVDF-metal/PVDF-ceramic composites according to an embodiment of the present disclosure. The system facilitates the development of polymer dielectrics from two-component polymer composites composed of ferroelectric polymer PVDF and metallic nanofillers/ferroelectric ceramic nanofillers. The additional presence of spherulites made of cold-pressed polymer composites results in effective charge storage at the interfaces of the spherulites. The system 100 includes an agate mortar and pestle 102 for mixing a mixture of ferroelectric polymer and metallic/ceramic fillers for about 2 hours.

In one embodiment, a hydraulic press 104 is mechanically connected to the agate mortar 100 and ram 102 to compress the powder mixture poured into a die/punch 106 to form a plurality of samples of the powder mixture into pellets using a room temperature cold pressing process the development of polymer dielectrics.

In another embodiment, the powder mixture is poured through a die/punch 106 and pressed at a pressure of 10 MPa - 30 MPa by the hydraulic press 104 for 10 minutes at room temperature to form the plurality of samples in the form of 12 mm and a thickness of about 1 mm - 2 mm.

In another embodiment, the cold-pressing process keeps alive the existing spherulites of the ferroelectric polymers and also their composites, causing higher charge storage at these natural interfaces.

In another embodiment, the effective role of the polymer spherulites of ferroelectric polymers in storing electrical charges was demonstrated through the use of a ferroelectric polymer [polyvinylidene fluoride (PVDF)] and a non-ferroelectric polymer [low density polyethylene (LDPE)].

In another embodiment, high purity (99.9%) metallic/ceramic fillers are selected, eg, metal powders including nickel (Ni) with an initial particle size of ~10 µm - 20 µm) and nanocrystalline Ni (n-Ni) with a particle size of ~20 nm - 30 nm as well as ceramic fillers made of nano-BaTiO3 (n-BaTiO3) with a particle size < 100 nm for the production of polymer composites.

In another embodiment, processing to produce PVDF/n-Ni polymer nanocomposites and PVDF/n-BaTiO 3 polymer nanocomposites with a higher degree of homogeneity and temperature-stabilized samples is demonstrated.

In another embodiment, processing to block a continuous network formation of the conductive/ceramic fillers is demonstrated to produce a blockage of the continuous conductive paths of the conductive fillers or the continuous network of ceramic fillers in the base polymer matrix.

An objective of the present disclosure is the fabrication of high performance polymer dielectrics from polymer nanocomposites composed of ferroelectric polymer PVDF and metal nanofillers/ferroelectric ceramic nanofillers.

In another embodiment, the metallic fillers of nano-Ni metal particles are mixed with the PVDF for about 2 hours and the multiple samples are compacted at room temperature and a pressure of 10 MPa-30 MPa with the hydraulic press 104 in the form of pellets with a 11 mm in diameter and 1.5 mm thick.

In another embodiment, the ceramic fillers made of n-BaTiO3 (Aldrich) with a particle size <100 nm are mixed with the PVDF at different volume fractions of n-BaTiO3[f _BaTiO3 ] for 2 hours and the large number of samples in the form of pellets Room temperature consolidation taken at a pressure of 10 MPa - 30 MPa using hydraulic press 104.

Flexible high-dielectric-constant ferroelectric polymer nanocomposites (PNC) are the latest materials under development that require commercialization. The incorporation of conductive nanofillers such as metal nanopowders, ferroelectric ceramic nanopowders, carbon nanotubes, graphene, graphite, carbon black, other carbon nanostructures, etc. into a ferroelectric polymer matrix, e.g. B. PVDF, is the common development method when it comes to the development of polymer dielectrics.

In developing these PNCs, hot casting of the polymer/filler mixture is the traditional process, with scientists focusing on the type of fillers to create more interfaces in the PNC and improve the dielectric constant of the PNC for their applications as dielectric materials in Increase capacitors and other electronic packages. In conventional hot forming, the melting of the polymer causes the fillers to agglomerate and the continuous network of conductive fillers in the matrix results in the formation of continuous conductive paths, thereby losing the property of storing electric charge and making the sample very heterogeneous/conductive will. Some of the interesting PNC for energy storage applications manufactured by the traditional hot casting process can be listed as follows. With the aim of developing high-dielectric materials, non-ferroelectric polymer-based PNCs were also tested. Ferroelectric polymers, e.g. B. PVDF-based polymer-ceramics from PVDF/BaTiO3 composite materials were produced with the aim of developing high-dielectric materials. Ferroelectric polymers, PVDF-based organic and inorganic (metal/carbon structures) percolative PNC have also been fabricated with the aim of developing high dielectric materials.

Therefore, with the aim of keeping these networks of conductive fillers blocked by an insulating layer of the polymer and maintaining the homogeneity of the samples, thereby increasing their ability to store the electric charge, a new method for the development of polymer composites has to be developed. The present invention relates to the production of high-K dielectric polymer materials in which the spherulites of these ferroelectric polymers, which consist of PVDF/n-Ni, PVDF/µ-Nί and PVDF/n-BaTiO3, are retained by the cold pressing process. The individual steps are described below.

Step 1: The polymers, polyvinylidene fluoride (PVDF), low density polyethylene (LDPE) and high purity (99.9%) metal powders such as nickel (Ni) with an initial particle size of ~(10 µm -20 µm) are sourced from Alfa Assar .

Step 2: The purchased Ni(m-Ni) is also milled for 60 hours to obtain nanocrystalline Ni(n-Ni) with particle size ~20nm-30nm. Milling was performed in toluene and tungsten carbide milling media, using the Ball to powder weight ratio was 10:1 at a milling speed of 300 rpm.

Step 3: The polymeric PVDF and the purchased Ni metal particles are mixed by mixing with an agate mortar/pestle for 2 hours and the final samples are pressed in the form of pellets at room temperature under a pressure of 30 MPa using a hydraulic press 104 in Solidified in the form of pellets with a diameter of 11 mm and a thickness of 1.5 mm under a pressure of 8 MPa at room temperature.

Step 4: The powders of PVDF polymer and n-Ni metal particles are mixed with an agate mortar/pestle for 2 hours and the final samples are pelletized at room temperature (300K) under a pressure of 30 MPa with the help a hydraulic press 104, in the form of pellets 11 mm in diameter and 1.5 mm thick under a pressure of 8 MPa at room temperature.

Step 5: The composite powders of PVDF (Alfa Assar) and n-BaTiO3 (Aldrich) with a particle size < 100 nm are prepared with different volume fractions of n-BaTiO3[f _BaTiO3 ] by mixing for 2 hours with an agate mortar/pestle, and the Final samples are consolidated in the form of pellets at room temperature under a pressure of 30 MPa using a hydraulic press 104.

Step 6: Powders of PVDF/n-Ni and LDPE/n-Ni were mixed for 2 hours using a mortar and pestle, and the mixed powders were heated by the conventional method at a temperature of 200°C and 130°C (above the melting temperature of the polymers) hot molded at a pressure of 10 MPa. Several samples with a diameter of 13 mm and a thickness of 1.6 mm were prepared in order to get as close as possible to the value of fc.

2 Figure 12 shows the FESEM image of cold-pressed bare PVDF showing spherulites and the excellent interfaces between them, while the hot-formed PVDF shows no spherulites and interfaces. 3 shows the comparison of the FESEM images of cold-pressed pure LDPE and hot-pressed LDPE, which show no spherulites and interfaces. 4 shows the comparison of the dielectric behavior of pure PVDF produced by cold pressing and hot pressing, inset: spherulites of cold pressed PVDF.

5 shows the FESEM images of cold-pressed PVDF/nano-nickel composites. 6 shows the FESEM images of cold-pressed bare PVDF and PVDF/n-BaTiO3 nanocomposites. 7 shows the change in relative crystallinity of pure PVDF (a) X-ray diffraction data from cold and hot pressed samples, and in the inset: larger view showing the change in crystalline peak area (b) FTIR data from cold and hot pressed samples. 8th Figure 1 shows the Differential Scanning Calorimetry (DSC) plots of the cold-pressed PVDF/n-Ni composites, showing their stability with increasing temperature.

9 shows micrographs of cold-pressed pure PVDF and PVDF/µ-Ni composites with different f _con . 10 shows micrographs of hot-pressed pure PVDF and PVDF/µ-Ni composites with different f _con . 11 shows micrographs of cold pressed pure PVDF and PVDF/n-Ni composites with different f _con . 12 shows the micrographs of the composites with different f _con of series D, ie hot pressed PVDF/n-Ni composites.

The static dielectric constant of ∼300-2000 with a reduced loss tangent of ~0.05-10 opens the applicability of these materials made by the current process as electronic packaging materials.

The developed system facilitates the fabrication of nanonickel-reinforced ferroelectric polymer, e.g. PVDF, while avoiding a non-ferroelectric polymer matrix, resulting in a stable polymer nanocomposite with very high dielectric constant and low loss tangent. The nanocomposite is made by cold pressing the mechanically mixed PVDF and nano-Ni powders using an agate mortar 100 and pestle 102 . The developed system leads to very homogeneous samples. The developed system yields a polymer nanocomposite with higher interfaces, both artificial and natural, with higher charge storage capability, resulting in better polymer dielectrics. With the developed system, a polymer dielectric with a high dielectric constant and a low loss tangent is obtained, which is suitable for capacitor applications.

Used abbreviations:

• PVDF : Poly(vinylidene fluoride)
• LDPE : Low Density Polyethylene
• PNC : polymer nanocomposites
• PD : Polymer Dielectrics

The system is tested on more than 200 samples. The polymer composite mixture based on PVDF polymer, which is kept at room temperature under a pressure of 10 MPa to 30 MPa for 10-15 minutes, develops better polymer dielectrics than the conventional hot-molded polymer dielectrics.

The figures and the preceding description give examples of embodiments. Those skilled in the art will understand that one or more of the elements described may well be combined into a single functional element. Alternatively, certain elements can be broken down into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, the order of the processes described herein may be changed and is not limited to the manner described herein. Additionally, the actions of a flowchart need not be performed in the order shown; Also, not all actions have to be carried out. Also, the actions that are not dependent on other actions can be performed in parallel with the other actions. The scope of the embodiments is in no way limited by these specific examples. Numerous variations are possible, regardless of whether they are explicitly mentioned in the description or not, e.g. B. Differences in structure, dimensions and use of materials. The scope of the embodiments is at least as broad as indicated in the following claims.

Advantages, other benefits, and solutions to problems have been described above with respect to particular embodiments. However, the benefits, advantages, problem solutions, and components that can cause an advantage, benefit, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or component of any or all claims.

Reference List

100

System for the development of improved ferroelectric polymer dielectrics based on PVDF-metal/PVDF-ceramic composites

102

An agate mortar and pestle

104

A hydraulic press

106

A die/punch

402

cold press

404

hot press

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• WO 2016142848 A1 [0004]
• US9556321B2 [0005]
• US 8729182 B2 [0006]
• US20130317170A1 [0007]
• US20110315914A1 [0008]
• US7609504B2 [0009]
• US 9732175 B2 [0010]
• US9011627B2 [0011]

Claims (10)

A system for developing improved polymer-based ferroelectric polymer dielectrics from PVDF-metal/PVDF-ceramic composites, the system comprising: an agate mortar and pestle for mixing a mixture of ferroelectric polymer and metallic/ceramic fillers for about 2 hours; and discloses a hydraulic press for pressing mixture powder poured into a die to produce a plurality of samples of the powder mixture in the form of pellets using a cold pressing process at room temperature to develop polymer dielectrics. system after claim 1 , in which the powder mixture is poured through a die/punch and pressed with a pressure of 10-30 MPa by the hydraulic press for 10 minutes at room temperature to obtain several samples in the form of pellets with a diameter of 12 mm and a thickness of approx 1mm-2mm to produce. system after claim 1 , in which the process of cold pressing keeps alive the existing spherulites of the ferroelectric polymers and also their composites, increasing the charge storage at these natural interfaces. system after claim 1 , wherein the ferroelectric polymer is selected from a group of polyvinylidene fluoride (PVDF) and low density polyethylene (LDPE). system after claim 1 , where the metallic/ceramic fillers are selected from a group of high purity (99.9%) metal powders including nickel (Ni) with an initial particle size of ~10 µm -20 µm. system after claim 5 , wherein the Ni (µ-Ni) is milled for 60 hours to obtain nanocrystalline Ni (n-Ni) with a particle size of ~20nm-30nm, the milling being carried out in toluene and tungsten carbide milling media by using the Ball to powder weight ratio is maintained at 10:1 at a milling speed of 300 rpm. The system after claim 1 , wherein when processing the PVDF/n-Ni polymer nanocomposite sample with higher degree of homogeneity and stabilized samples with respect to temperatures can be obtained. system after claim 1 wherein the processing to block coherent network formation of the conductive fillers is to produce a blockage of the continuous conductive paths of the conductive fillers in the polymer matrix. system after claim 1 , in which the metallic fillers made of nano-Ni metal particles are mixed with the PVDF for about 2 hours and the multiple samples using the hydraulic press in the form of pellets with a diameter of 11 mm and a thickness of 1.5 mm under one pressure of 8 MPa at room temperature under solidification at a pressure of 30 MPa. system after claim 1 , where the ceramic fillers of n-BaTiO3 with a particle size <100 nm are mixed with the PVDF at a different volume fraction of n-BaTiO3[fBaTiO3] for 2 h and the majority of the samples in the form of pellets with solidification at room temperature and a pressure of 30 MPa using the hydraulic press.

Images