EP2303956A1 - Matériau composite avec nanopoudre et utilisation du matériau composite - Google Patents

Matériau composite avec nanopoudre et utilisation du matériau composite

Info

Publication number
EP2303956A1
EP2303956A1 EP09772249A EP09772249A EP2303956A1 EP 2303956 A1 EP2303956 A1 EP 2303956A1 EP 09772249 A EP09772249 A EP 09772249A EP 09772249 A EP09772249 A EP 09772249A EP 2303956 A1 EP2303956 A1 EP 2303956A1
Authority
EP
European Patent Office
Prior art keywords
filler
powder
composite material
fraction
composite
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP09772249A
Other languages
German (de)
English (en)
Inventor
Gerhard Piecha
Matthias ÜBLER
Wilfried Albert
Mario Brockschmidt
Peter GRÖPPEL
Vicky Jablonski
Uwe Schönamsgruber
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Publication of EP2303956A1 publication Critical patent/EP2303956A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/01—Use of inorganic substances as compounding ingredients characterized by their specific function
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/011—Nanostructured additives
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/014—Additives containing two or more different additives of the same subgroup in C08K

Definitions

  • the invention relates to a composite material comprising at least one base material and at least one filler-powder mixture distributed in the base material, wherein the filler-powder mixture comprises a filler powder fraction and at least one further filler powder fraction, the filler powder Fraction has an average powder particle diameter (D 50 ) selected from the range of 1 ⁇ m to 100 ⁇ m, and a total filler content (degree of filling) of the filler-powder mixture in the composite material is more than 50% by weight.
  • D 50 average powder particle diameter
  • degree of filling degree of filling
  • the composite material is, for example, a thermoset cast resin system, as used in electrical engineering for producing high quality composite materials (e.g., insulating and bonding materials)
  • Construction materials is used. With the help of the fillers of the cast resin system electrical, mechanical and thermal properties of the resulting composite material can be adjusted. Such properties are, for example, the thermal conductivity, the linear thermal expansion coefficient, the modulus of elasticity or the fracture toughness of the composite material. Likewise, the reaction enthalpy that is released during the curing process of the composite material can be controlled.
  • Some of these properties depend on the level of filling, and thus the size of the surface to be wetted, which is introduced by the filler in the composite material.
  • volume effect dominates the influence on the Properties of the composite. This concerns in particular the electrical properties.
  • Surface effects that is, effects that occur due to the interface between the base material of the composite material or the composite and the filler, play only a minor role.
  • the described increase in viscosity can be achieved by increasing a processing temperature of the cast resin system or by the use of additives that increase the diligence ability of the cast resin system. Both solutions involve an undesirable limitation of the processability (eg of a process window) of the cast resin system as well as an increase in the cost of its processing. Likewise, a reduction in the degree of filling would counteract the increase in viscosity through the use of fine filler particles. But this is in terms of one the widest possible range of variation of the properties of the resulting composite undesirable.
  • WO 03/072646 A is a highly filled, yet flowable composite material, which consists of a filled with a filler casting resin system.
  • the base material of the cast resin system is, for example, an epoxy-based resin in the form of a mixture of resin and hardener.
  • the filler is a filler-powder mixture of fine, medium coarse and coarse filler-powder fractions.
  • the fine filler powder fraction is composed of powder particles having an average powder particle diameter in the range of 1 .mu.m to 10 .mu.m.
  • the average powder particle diameters of the medium coarse and coarse powder particle fractions are selected from the range of 10 ⁇ m to 100 ⁇ m and from the range of 100 ⁇ m to 1000 ⁇ m.
  • filling level By using several specifically matched filler fractions with different particle size distributions (filler-powder mixture with multimodal particle size distribution), it has been possible to increase the filling level by about 10% by weight and, to a lesser extent, also to increase a proportion of the fine filler powder fraction while maintaining the viscosity level of the potting compound.
  • Object of the present invention is to provide a composite material in which a high filler content is possible and at the same time a viscosity of the composite material remains low at a lower cost compared to the prior art.
  • a composite material comprising at least one base material and at least one distributed in the base material filler-powder mixture, wherein the filler-powder mixture comprises a filler powder fraction and at least one further filler powder fraction, the Filler-powder fraction has an average powder particle diameter selected from the range of 1 ⁇ m to 100 ⁇ m, and a total filler content of the filler-powder mixture in the composite material is more than 50% by weight.
  • the composite material is characterized in that the further filler powder fraction has a further average powder particle diameter selected from the range of 1 nm to 100 nm and a proportion of the further filler powder fraction on the filler powder mixture is selected from the range of 0.1% by weight to 50% by weight.
  • the composite material is a particle composite of base material and filler.
  • the base material represents a matrix in which the filler or the filler particles of the filler-powder mixture are distributed. Preferably, there is a homogeneous distribution of the filler particles in the base material.
  • the filler-powder mixture has a multimodal particle size distribution. At least one of the filler powder fractions has nanoscale filler particles.
  • the average powder particle diameter (D 50 ) of this filler powder fraction is selected in the range of 1 nm to 100 nm, and preferably in the range of 1 nm to 50 nm.
  • the viscosity of the composite material can be adjusted within a wide range.
  • the proportion of the further filler powder fraction in the filler-powder mixture from the range of 0.4 wt.% To 40 wt.% And in particular from the range of 0.5 wt.% To 20 % By weight selected.
  • the proportion of the further filler powder fraction of the filler-powder mixture and the total filler content of the filler-powder mixture in the composite material are chosen so that the further filler powder fraction with a proportion of not more than 10 Wt.% And in particular in a proportion from the range of 0.1 wt.% To 5 wt.% Contained in the composite material.
  • the further average powder particle diameter is selected from the range of 5 nm to 30 nm.
  • the average powder particle diameter is 20 nm.
  • the total filler content of the filler-powder mixture in the composite material is selected from the range of 60% by weight to 80% by weight.
  • a higher total filler content of For example, 90% by weight or 95% by weight are also conceivable.
  • the properties of the composite material and the composite material obtained from the composite material can be adjusted in a very wide range.
  • the composite material is particularly suitable as a casting material for use in a casting process.
  • the composite material can be used very well in the pressure gelling technique.
  • the individual filler-powder fractions can be multi-modal. This means that they in turn can be composed of several fractions with different particle size distributions.
  • the filler powder fraction or the further filler powder fraction is bi- or trimodal.
  • the filler-powder fractions may consist of the same or different materials. According to a particular embodiment, therefore, the filler powder fractions have powder particles with the same or different chemical composition. Thus, for example, it is conceivable to add nanoscale quartz powder or fused silica (SiO 2 ) merely to adjust the viscosity of the composite material. The electrical properties of the resulting composite are adjusted by the microsized filler powder fraction.
  • the micro-scale filler is a barium titanate or a lead zirconate titanate (PZT). It is also conceivable that at least one of the filler-powder fractions consists of mixtures of powder particles of different chemical compositions.
  • the micro-scale filler-powder fraction could be a mixture of powder particles with chemical compositions of the barium-calcium-strontium-titanate system (Ba x Ca x Sr y x - y TiOs).
  • the nanoscale further filler powder fraction could be a Mixture of powder particles of silicon dioxide and alumina (Al 2 O 3 ) be.
  • Aluminum Oxyhydrate (AlO (OH)) is also conceivable as a material of the nano-scale further filler powder fraction.
  • the materials mentioned could also be used for the micro-scale filler-powder fraction.
  • the chemical composition of the powder particles is selected from the group of metal carbonate, metal carbide, metal nitride, metal oxide and metal sulfide.
  • metal carbonates for example dolomite (CaCO 3) t, can be used to reduce the flammability of the resulting composite.
  • Al 2 O 3 , TiO 2 , Fe 2 O 3 , Fe 3 O 4 , CeO 2 or ZrO 2 are suitable for optimizing the various thermal properties.
  • the nitrides AlN, BN, B 3 N 4 or Si 3 N 4 are suitable for increasing the hardness of the resulting composite material.
  • An improvement of the thermal conductivity is with the
  • the compounds used can, as can be seen from the examples, have only one anionic component in each case.
  • mixed compounds can be used which have a plurality of anionic components.
  • Such a mixed compound is, for example, a metal-oxi-sulfide.
  • the metal oxides may comprise a single type of metal.
  • the metal oxide has a mixed oxide with at least two different metals.
  • a mixed oxide is, for example, lead zirconate titanate, with the aid of which the electrical properties of the composite material and thus of the resulting
  • Composite can be adjusted in a wide range. Also materials of the already mentioned barium-calcium-strontium-titanate system are suitable, the adjust the electrical properties of the composite material.
  • mineral substances are also suitable materials for the filler-powder fractions.
  • Materials include mica and slate meal. These materials are used inter alia to reduce the combustibility of the composite material,
  • filler particles of the filler powder fraction and / or filler particles of the further filler powder fraction have a spherical, splintery, platelet-shaped and / or short-phase particle shape from the group. It has been found that, in particular, the spherical particle shape has a favorable influence on the viscosity of the composite material.
  • the filler-powder fractions may contain filler particles having a core-shell structure. Such particles are characterized by a radial gradient with respect to their composition.
  • filler-powder fractions used can iron uncoated filler particles.
  • filler particles of the filler powder fraction and / or filler particles of the further filler powder fraction have a particle coating.
  • the filler particles are coated.
  • the coating can be organic or inorganic.
  • the coating can be applied to the coating process in a coating process
  • Particle surfaces of the powder particles are applied.
  • the base material may be inorganic in nature.
  • the base material is an organic material.
  • the organic base material is a crosslinkable or at least partially crosslinked polymer base material.
  • An underlying crosslinking reaction may be a polymerization, polyaddition or polycondensation.
  • the crosslinking reaction can be initiated chemically, for example anionic or cationic. Likewise, a crosslinking reaction induced by light or by the application of heat is possible.
  • the composite material is used as potting compound.
  • the potting compound is used for example in a vacuum casting.
  • the potting compound has a liquid base material.
  • the liquid base material consists for example of di- or poly-epoxy compounds, hardener components based on amine, acid anhydride or isocyanate and an accelerator component for an anionic or cationic reaction initiation.
  • further additives may be included, for example defoamers, wetting aids, flexibilizers and the like.
  • the nano-scale further filler powder fraction can be used with the aid of a liquid. Particularly suitable is the use of a so-called suspension-batch mixture.
  • the composite material can also be used in the automatic pressure gelling technique. Due to the adjustability of the viscosity of the composite material, it is also particularly suitable for this technique.
  • the composite material is used as a molding compound.
  • the composite material is first brought into a desired shape by applying a pressure and then cured.
  • suitable viscosity of the composite material can be adjusted.
  • the composite material as described above is used for producing a composite material, preferably for producing a filled polymer material.
  • the polymer material comprises the base material of the composite material in cured form.
  • the filler-powder mixture is distributed.
  • the composite material is used as a construction material (structural material).
  • the construction material is produced.
  • a housing or the like is produced from the composite material.
  • the composite material is processed and then cured. The result is the housing with the composite material.
  • Powder particles of the further filler powder the workability ensured by a low viscosity of the composite material.
  • the composite material can be characterized by very good rheological properties and is therefore particularly suitable for use as potting compound.
  • Table 1 contains a summary of the starting materials used with their essential properties. These include the average particle diameter, the specific surface area.
  • the filler types A, B and C were used as a micro-scale filler powder fraction.
  • the filler type D was used as nano-scale further filler powder fraction. All filler types consist of SiO 2 .
  • Silbond® includes Quarzmehl permit the quartz works Frechen.
  • Table 2 contains filler-powder blends (types E to I) made from filler powder types A to D.
  • Type E represents a comparative powder mixture which does not belong to the invention and has only microscale filler powder fractions.
  • Epoxy-based composites were made from the filler-powder blends.
  • Table 3 contains the viscosity values of the composite materials as a function of the degree of filling.
  • Table 4 contains examples of acid anhydride cured epoxy potting systems depending on

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Nanotechnology (AREA)
  • Physics & Mathematics (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Composite Materials (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

L’invention concerne un matériau composite, comprenant au moins un matériau de base et au moins un mélange de poudre-matière de remplissage réparti dans le matériau de base. Le mélange de poudre-matière de remplissage comprenant une fraction de poudre-matière de remplissage et au moins une autre fraction de poudre-matière de remplissage, la fraction de poudre-matière de remplissage présentant un diamètre de particule de poudre moyen (D50) choisi dans la plage de 1 µm à 100 µm et un pourcentage total de matière de remplissage (taux de remplissage) du mélange poudre-matière de remplissage dans le matériau composite étant de plus de 50 % en poids. Le matériau composite est caractérisé en ce que l’autre fraction de poudre-matière de remplissage présente un autre diamètre de particule de poudre moyen choisi dans la plage de 1 nm à 50 nm et un pourcentage de l’autre fraction de poudre-matière de remplissage dans le mélange poudre-matière de remplissage est choisi dans la plage de 0,1 % en poids à 50 % en poids. Il s’est avéré qu’en présence de particules de matière de remplissage à l’échelle nanométrique, on peut obtenir un taux de remplissage plus élevé pour une viscosité moindre. Le matériau composite convient en particulier comme masse de scellement (système de résine coulée).
EP09772249A 2008-06-30 2009-05-29 Matériau composite avec nanopoudre et utilisation du matériau composite Withdrawn EP2303956A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102008030904A DE102008030904A1 (de) 2008-06-30 2008-06-30 Verbundmaterial mit Nano-Pulver und Verwendung des Verbundmaterials
PCT/EP2009/056612 WO2010000549A1 (fr) 2008-06-30 2009-05-29 Matériau composite avec nanopoudre et utilisation du matériau composite

Publications (1)

Publication Number Publication Date
EP2303956A1 true EP2303956A1 (fr) 2011-04-06

Family

ID=40943780

Family Applications (1)

Application Number Title Priority Date Filing Date
EP09772249A Withdrawn EP2303956A1 (fr) 2008-06-30 2009-05-29 Matériau composite avec nanopoudre et utilisation du matériau composite

Country Status (5)

Country Link
US (1) US20110098383A1 (fr)
EP (1) EP2303956A1 (fr)
CN (1) CN102076749A (fr)
DE (1) DE102008030904A1 (fr)
WO (1) WO2010000549A1 (fr)

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DE202009017047U1 (de) * 2009-12-17 2011-05-05 Rehau Ag + Co. Titandioxidhaltige Zusammensetzung
DE102010014319A1 (de) 2010-01-29 2011-08-04 Siemens Aktiengesellschaft, 80333 Dämpfungsmasse für Ultraschallsensor, Verwendung eines Epoxidharzes
WO2011095208A1 (fr) * 2010-02-03 2011-08-11 Abb Research Ltd Système d'isolation électrique
DE102010015398A1 (de) * 2010-04-19 2011-10-20 Siemens Aktiengesellschaft Isolationsverbundmaterial zur elektrischen Isolation, Verfahren zur Herstellung und Verwendung desselben
US8958780B2 (en) * 2010-10-07 2015-02-17 Blackberry Limited Provisioning based on application and device capability
US9512036B2 (en) 2010-10-26 2016-12-06 Massachusetts Institute Of Technology In-fiber particle generation
DE102011083409A1 (de) 2011-09-26 2013-03-28 Siemens Aktiengesellschaft Isoliersysteme mit verbesserter Teilentladungsbeständigkeit, Verfahren zur Herstellung dazu
DE102012205650A1 (de) 2012-04-05 2013-10-10 Siemens Aktiengesellschaft Isolierstoff für rotierende Maschinen
DE102012211762A1 (de) * 2012-07-05 2014-01-09 Siemens Aktiengesellschaft Formulierung, Verwendung der Formulierung und Isoliersystem für rotierende elektrische Maschinen
US10406723B2 (en) 2013-03-13 2019-09-10 University Of Central Florida Research Foundation Dynamic in-fiber particle production with precise dimensional control
DE102019204191A1 (de) * 2019-03-27 2020-10-01 Siemens Aktiengesellschaft Gießharz, Formstoff daraus, Verwendung dazu und eine elektrische Isolierung

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US6054222A (en) * 1997-02-20 2000-04-25 Kabushiki Kaisha Toshiba Epoxy resin composition, resin-encapsulated semiconductor device using the same, epoxy resin molding material and epoxy resin composite tablet
DE10207401A1 (de) * 2001-03-30 2002-10-02 Degussa Hochgefüllte pastöse siliciumorganische Nano- und/oder Mikrohybridkapseln enthaltende Zusammensetzung für kratz- und/oder abriebfeste Beschichtungen
EP1249470A3 (fr) * 2001-03-30 2005-12-28 Degussa AG Composition fortement chargée en nano et/ou microcapsules hybrides à base de silice organique pâteuse pour des revêtements résistants aux rayures et à l'abrasion
AU2002361585B2 (en) * 2001-11-03 2005-08-25 Nanophase Technologies Corporation Nanostructured compositions
EP1478688A1 (fr) 2002-02-28 2004-11-24 Siemens Aktiengesellschaft Systeme de resine moulee a part de charge augmentee
DE502004007114D1 (de) * 2003-09-29 2008-06-26 Bosch Gmbh Robert Härtbares Reaktionsharzsystem
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DE102005032353B3 (de) * 2005-07-08 2006-08-24 Institut für Oberflächenmodifizierung e.V. Metallorganisches Nanopulver, Verfahren zu ihrer Herstellung sowie diese enthaltende Komposite
DE102007023557B4 (de) * 2007-05-21 2010-11-25 Siemens Ag Schutzbeschichtung und Verwendung davon für Fahrleitungsisolatoren
EP2131373B1 (fr) * 2008-06-05 2016-11-02 TRIDELTA Weichferrite GmbH Matériau magnétique doux et procédé de fabrication d'objets à partir de ce matériau magnétique doux

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Also Published As

Publication number Publication date
WO2010000549A1 (fr) 2010-01-07
CN102076749A (zh) 2011-05-25
US20110098383A1 (en) 2011-04-28
DE102008030904A1 (de) 2009-12-31

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