EP1922369A1 - Surface-modified nanoparticles from aluminum oxide and oxides of elements of the first and second main group of the periodic system and the production thereof - Google Patents

Surface-modified nanoparticles from aluminum oxide and oxides of elements of the first and second main group of the periodic system and the production thereof

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Publication number
EP1922369A1
EP1922369A1 EP06776873A EP06776873A EP1922369A1 EP 1922369 A1 EP1922369 A1 EP 1922369A1 EP 06776873 A EP06776873 A EP 06776873A EP 06776873 A EP06776873 A EP 06776873A EP 1922369 A1 EP1922369 A1 EP 1922369A1
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EP
European Patent Office
Prior art keywords
nanoparticles
agglomerates
oxides
modified
modified nanoparticles
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.)
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Application number
EP06776873A
Other languages
German (de)
French (fr)
Inventor
Norbert RÖSCH
Ernst Krendlinger
Anja Heinze
Karl Zeisberger
Peter Klug
Waltraud Simsch
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.)
Archroma IP GmbH
Original Assignee
Clariant International Ltd
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Filing date
Publication date
Priority claimed from DE102005039435A external-priority patent/DE102005039435A1/en
Priority claimed from DE102005039436A external-priority patent/DE102005039436B4/en
Priority claimed from DE102006012319A external-priority patent/DE102006012319A1/en
Priority claimed from DE200610020516 external-priority patent/DE102006020516A1/en
Application filed by Clariant International Ltd filed Critical Clariant International Ltd
Publication of EP1922369A1 publication Critical patent/EP1922369A1/en
Withdrawn legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
    • C09C1/40—Compounds of aluminium
    • C09C1/407—Aluminium oxides or hydroxides
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
    • C09C1/40—Compounds of aluminium
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F7/00—Compounds of aluminium
    • C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F7/00—Compounds of aluminium
    • C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
    • C01F7/021—After-treatment of oxides or hydroxides
    • C01F7/023—Grinding, deagglomeration or disintegration
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/04—Physical treatment, e.g. grinding, treatment with ultrasonic vibrations
    • C09C3/041—Grinding
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
    • C09C3/12—Treatment with organosilicon compounds
    • 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
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/50—Solid solutions
    • C01P2002/52—Solid solutions containing elements as dopants
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/30—Particle morphology extending in three dimensions
    • C01P2004/32—Spheres
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/50—Agglomerated particles
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
    • Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
    • Y10T428/2991—Coated
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
    • Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
    • Y10T428/2991—Coated
    • Y10T428/2993—Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.]
    • Y10T428/2995—Silane, siloxane or silicone coating

Definitions

  • the present invention relates to surface-modified nanoparticles, and their preparation, wherein the nanoparticles consist of Al 2 O 3 with fractions of oxides of the elements of the I. and II. Main group of the Periodic Table.
  • Fine alumina powders are used in particular for ceramic applications, for matrix reinforcement of organic or metallic layers, as fillers, polishing powders, for the production of abrasives, as additives in paints and laminates as well as for other special applications.
  • the alumina powders are often surface-modified with silanes for better adaptation to the resin layers. Both the adhesion and the optical property are improved. This manifests itself in a decrease in turbidity.
  • silane-modified fumed alumina for use in toners (DE 42 02 694).
  • Nanoparticles of Al 2 O 3 whose surface is modified with silanes are described in WO 02/051376. In their preparation, one starts from a commercially available Al 2 O 3 , which is then treated with a silane. Production of the nanoparticles and their modification are thus carried out in two separate steps. Commercially available nanocorundum (0C-Al 2 O 3 ) is present as a powder. Due to the high surface energy, however, nanoparticles always accumulate to form larger agglomerates, so that in reality they are not true nanoparticles. Accordingly, the particles coated with silanes according to WO 02/051 376 are correspondingly large.
  • EP 1 123 354 (IOM Amsterdam) describes polymerisable metal oxide particles which are modified with various compounds which have a reactive, wear functional group. Suitable modifiable compounds include silanes.
  • the metal oxide particles here exclusively oxides of a metal or metalloid of the third to sixth main group, the first to eighth subgroup of the periodic table or the lanthanides are used, mixed oxides with a proportion of oxides of the first and second main groups are not described.
  • WO 2004/069400 (InM Saar Hampshiren) describes a process for the preparation of a functional colloid, in which particles are mechanically comminuted in a dispersant in the presence of a modifier, so that the modifier is at least partially chemically bound to the comminuted colloid particles. This method is based on homogeneous particles, the deagglomeration of agglomerates from existing nanoparticles is not disclosed.
  • No. 6,896,958 B1 (nanophase) describes a process in which nanocrystalline substances from the group of ceramic or metallic substances are dispersed in a solvent and treated with siloxanes. The resulting dispersions are used in crosslinkable resins to improve the scratch resistance.
  • surface-modified nanoparticles in the form of mixed oxides of Al 2 O 3 containing oxides of elements from the first and second main groups of the Periodic Table, are particularly easy to produce by deagglomeration of agglomerates of these mixed oxides in a solvent with the addition of a coating agent to let.
  • the coating agents used are preferably silanes or siloxanes.
  • the invention relates to surface-modified nanoparticles consisting of 50-99.9% by weight of aluminum oxide and 0.1-50% by weight of oxides of elements of the 1st or 2nd main group of the Periodic Table, these nanoparticles having a coating agent on the surface are modified.
  • the alumina in these mixed oxides is preferably present for the most part in the rhombohedral ⁇ -modification (corundum).
  • the mixed oxides according to the present invention preferably have a crystal it size of less than 1 micron, preferably less than 0.2 microns and more preferably between 0.001 and 0.09 microns. Particles of this size according to the invention will be referred to below as mixed oxide nanoparticles.
  • the mixed oxide nanoparticles according to the invention can be prepared by different processes described below. These process descriptions refer to the production of pure alumina particles, but it goes without saying that in all these process variants in addition to Al-containing starting compounds and those compounds from elements of the I. or II. Main group of the Periodic Table must be present to form the mixed oxides according to the invention. For this purpose, especially the chlorides, but also the oxides, oxychlorides, carbonates, sulfates or other suitable salts come into question. The amount of such oxide formers is such that the finished nanoparticles contain the aforementioned amounts of oxide MeO.
  • agglomerates of these mixed oxides are used, which are then deagglomerated to the desired particle size.
  • These agglomerates can be prepared by methods described below.
  • Such agglomerates can be prepared, for example, by various chemical syntheses. These are usually precipitation reactions (hydroxide precipitation, hydrolysis of organometallic compounds) with subsequent calcination. Crystallization seeds are often added to reduce the transition temperature to the ⁇ -alumina. The sols thus obtained are dried and thereby converted into a gel. The further calcination then takes place at temperatures between 350 0 C and 650 0 C. For the conversion to Ct-Al 2 O 3 must then be annealed at temperatures around 1000 0 C. The processes are described in detail in DE 199 22 492. Another way is the aerosol process. The desired molecules are obtained from chemical reactions of a Precursorgases or by rapid cooling of a supersaturated gas.
  • the formation of the particles occurs either through collision or the constant equilibrium evaporation and condensation of molecular clusters.
  • the newly formed particles grow by further collision with product molecules (condensation) and / or particles (coagulation). If the coagulation rate is greater than that of the new growth or growth, agglomerates of spherical primary particles are formed.
  • Nanoparticles are formed here by the decomposition of Precursormolekülen in the flame at 1500 0 C - 2500 0 C.
  • AICb So far only the corresponding clay could be produced.
  • Flame reactors are now used industrially for the synthesis of submicroparticles such as carbon black, pigment Ti ⁇ 2, silica and alumina.
  • Small particles can also be formed from drops with the help of centrifugal force, compressed air, sound, ultrasound and other methods.
  • the drops are then converted into powder by direct pyrolysis or by in situ reactions with other gases.
  • the spray and freeze drying should be mentioned.
  • precursor drops are transported through a high temperature field (flame, oven), resulting in rapid evaporation of the volatile component or initiating the decomposition reaction to the desired product.
  • the desired particles are collected in filters.
  • the production of BaTiO 3 from an aqueous solution of barium acetate and titanium lactate can be mentioned here.
  • the nanoparticles must be released. This is preferably done by grinding or by treatment with ultrasound. According to the invention, this deagglomeration takes place in the presence of a
  • Solvent and a coating agent preferably a silane, which saturates the resulting active and reactive surfaces by a chemical reaction or physical attachment during the milling process and thus prevents reagglomeration.
  • the nano-mixed oxide remains as a small particle. It is also possible to add the coating agent after deagglomeration.
  • agglomerates are used which, as described in Ber. DKG 74 (1997) no. 11/12, pp. 719-722, as previously described.
  • the starting point here is aluminum chlorohydrate, which has the formula Al 2 (OH) x Cl y , where x is a number from 2.5 to 5.5 and y is a number from 3.5 to 0.5 and the sum of x and y always 6.
  • This aluminum chlorohydrate is mixed with crystallization seeds as an aqueous solution, then dried and then subjected to a thermal treatment (calcination). Preference is given to starting from about 50% aqueous solutions, as they are commercially available.
  • Such a solution is mixed with nuclei which promote the formation of the ⁇ -modification of Al 2 O 3 . In particular, such nuclei cause a lowering of the temperature for the formation of the ⁇ -modification in the subsequent thermal treatment.
  • germs are preferably in question finely disperse corundum, diaspore or hematite. Particular preference is given to taking very finely divided ⁇ -Al 2 O 3 nuclei having an average particle size of less than 0.1 ⁇ m. In general, 2 to 3 wt .-% of germs based on the resulting alumina from.
  • This starting solution additionally contains oxide formers in order to produce the oxides MeO in the mixed oxide.
  • oxide formers especially the chlorides of the elements of the I. and II. Main group of the Periodic Table, in particular the chlorides of the elements Ca and Mg, but also other soluble or dispersible salts such as oxides, oxychlorides, carbonates or sulfates.
  • the amount of oxide generator is such that the finished nanoparticles contain 0.01 to 50% by weight of the oxide MeO.
  • the oxides of I. and II. Main group may be present as a separate phase in addition to the alumina or with this real mixed oxides such. Form spinels etc.
  • the term "mixed oxides" in the context of this invention should be understood to include both types.
  • This suspension of aluminum chlorohydrate, germs and oxide formers is then evaporated to dryness and subjected to a thermal treatment (calcination).
  • This calcination is carried out in suitable devices, for example in push-through, chamber, tube, rotary kiln or microwave ovens or in a fluidized bed reactor.
  • suitable devices for example in push-through, chamber, tube, rotary kiln or microwave ovens or in a fluidized bed reactor.
  • the temperature for the calcination should not exceed 1400 0 C.
  • the lower temperature limit depends on the desired yield of nanocrystalline mixed oxide, the desired residual chlorine content and the content of Germinate.
  • the formation of the nanoparticles begins at about 500 0 C, but to keep the chlorine content low and the yield of nanoparticles high, but you will work preferably at 700 to 1100 0 C, in particular at 1000 to 1100 0 C.
  • agglomerates accumulate in the form of nearly spherical nanoparticles. These particles consist of Al 2 O 3 and MeO. The content of MeO acts as an inhibitor of crystal growth and keeps the crystallite size small. As a result, the agglomerates, as obtained by the calcination described above, clearly differ from the particles used in the process described in WO 2004/069 400, which are coarser, inherently homogeneous particles and not agglomerates of pre-fabricated nanoparticles.
  • the agglomerates are preferably comminuted by wet grinding in a solvent, for example in an attritor mill, bead mill or stirred mill.
  • a solvent for example in an attritor mill, bead mill or stirred mill.
  • a suspension of nanoparticles with a d90 value of approximately 50 nm is obtained.
  • Another possibility for deagglomeration is sonication.
  • the deagglomeration in Make the presence of the coating agent, for example by adding the coating agent during grinding in the mill.
  • a second possibility consists of first destroying the agglomerates of the nanoparticles and then treating the nanoparticles, preferably in the form of a suspension in a solvent, with the coating agent.
  • Suitable solvents for deagglomeration are both water and customary solvents, preferably those which are also used in the paint industry, such as, for example, C 1 -C 4 -alcohols, in particular methanol, ethanol or isopropanol, acetone, tetrahydrofuran, butyl acetate.
  • an inorganic or organic acid such as HCl, HNO 3 , formic acid or acetic acid should be added to stabilize the resulting nanoparticles in the aqueous suspension.
  • the amount of acid may be 0.1 to 5 wt .-%, based on the mixed oxide.
  • aqueous suspension of the acid-modified nanoparticles is then preferably the grain fraction having a particle diameter of less than 20 nm separated by centrifugation.
  • the coating agent preferably a silane or siloxane
  • the nanoparticles thus treated precipitate are separated and dried to a powder, for example by freeze-drying.
  • Suitable coating agents are preferably silanes or siloxanes or mixtures thereof.
  • suitable coating agents are all substances which can bind physically to the surface of the mixed oxides (adsorption) or which can bond to form a chemical bond on the surface of the mixed oxide particles. Since the surface of the mixed oxide particles is hydrophilic and free hydroxy groups are available, suitable coating agents are alcohols, compounds having amino, hydroxyl, carbonyl, carboxyl or mercapto functions, silanes or siloxanes. Examples of such coating compositions are polyvinyl alcohol, mono-, di- and tricarboxylic acids, Amino acids, amines, waxes, surfactants, hydroxycarboxylic acids, organosilanes and organosiloxanes.
  • Suitable silanes or siloxanes are compounds of the formulas
  • R, R ', R ", R 1 " identical or different from each other, an alkyl radical having 1-18 C atoms or a phenyl radical or an alkylphenyl or a phenylalkyl radical having 6 - 18 C-atoms or a radical of the general formula - ( C m H 2m -O) pC q H 2 q + i or a radical of the general formula -C 3 H 2s Y or a radical of the general formula -XZn,
  • n is an integer meaning 1 ⁇ n ⁇ 1000, preferably 1 ⁇ n ⁇ 100
  • m is an integer 0 ⁇ m ⁇ 12
  • p is an integer 0 ⁇ p ⁇ 60
  • q is an integer 0 ⁇ q ⁇ 40
  • r is an integer 2 ⁇ r ⁇ 10 and s is an integer 0 ⁇ s ⁇ 18 and
  • Y is a reactive group, for example ⁇ , ⁇ -ethylenically unsaturated groups, such as (meth) acryloyl, vinyl or allyl groups, amino, amido, ureido, hydroxyl, epoxy, isocyanato, mercapto, sulfonyl, Phosphonyl, trialkoxylsilyl, alkyldialkoxysilyl, dialkylmonoalkoxysilyl, anhydride and / or carboxyl groups, imido, imino, sulfite, sulfate, sulfonate, phosphine, phosphite, phosphate, phosphonate groups, and X is a t-functional Oligomer with t an integer 2 ⁇ t ⁇ 8 and Z in turn a remainder
  • R [-Si (R 1 R 11 KH n Si (R 1 R 11 JR 1 ”) or cyclo - [-Si (R'R") - O-] r Si (R 1 R 11 JO- represents as defined above.
  • the t-functional oligomer X is preferably selected from:
  • radicals of oligoethers are compounds of the type - (C a H 2a -O) b - C a H 2a - or O- (C a H2a-O) b -CaH 2a -O with 2 ⁇ a ⁇ 12 and 1 ⁇ b ⁇ 60, z.
  • residues of oligoesters are compounds of the type -C b H 2b - (C (CO) C a H 2 a- (CO) O- C b H 2b -) c- or -OC b H 2b - (C ( CO) C a H 2a - (CO) OC b H 2b -) c -O- with a and b different or equal to 3 ⁇ a ⁇ 12, 3 ⁇ b ⁇ 12 and 1 ⁇ c ⁇ 30, z.
  • silanes of the type defined above are, for. Hexamethyldisiloxane, octamethyltrisiloxane, other homologous and isomeric compounds of the series Si n O n-1 (CH 3 ) 2 n + 2, where n is an integer 2 ⁇ n ⁇ 1000, e.g. B. Polydimethylsiloxane 200® fluid (2O cSt).
  • ⁇ -OH groups are also the corresponding difunctional compounds with epoxy, isocyanato, vinyl, AIIyI- and di (meth) acryloyl used, for.
  • R is an alkyl, such as. For example, methyl, ethyl, n-propyl, i-propyl, butyl n 1 to 20.
  • R is an alkyl, such as. Methyl, ethyl, n-propyl, i-propyl, butyl,
  • R 1 is an alkyl, such as. Methyl, ethyl, n-propyl, i-propyl, butyl,
  • R ' is a cycloalkyl n is an integer from 1 - 20 x + y 3 x 1 or 2 y 1 or 2 1 O
  • Preferred silanes are the silanes listed below: triethoxysilane, octadecyltimethoxysilane, 3- (trimethoxysilyl) -propylmethacrylate, 3- (trimethoxysilyl) -propylacrylate, 3- (trimethoxysilyl) -methylmethacrylate, 3- (trimethoxysilyl) -methylacrylate, 3- (trimethoxysilyl) ethylmethacrylate, 3- (trimethoxysilyl) -ethylacrylate, 3- (trimethoxysilyl) -pentylmethacrylate, 3- (trimethoxysilyl) -pentylacrylate, 3- (trimethoxysilyl) -hexylmethacrylate, 3- (trimethoxysilyl) -hexylacrylate, 3- (trimethoxysilyl) -butylmethacrylate , 3- (trimeth
  • Tetramethoxysilanes Tetramethoxysilanes, tetraethoxysilanes, oligomeric tetraethoxysilanes (DYNASIL® 40 from Degussa), tetra-n-propoxysilanes, 3-glycidyloxypropyltrimethoxysilanes, 3-glycidyloxypropyltriethoxysilanes, 3-methacryloxypropyltrimethoxysilanes, vinyltrimethoxysilanes, vinyltriethoxysilanes, 3-mercaptopropyltrimethoxysilanes,
  • 3-aminopropyltriethoxysilanes 3-aminopropyltrimethoxysilanes, 2-aminoethyl-3-aminopropyltrimethoxysilanes, triaminofunctional propyltrimethoxysilanes (DYN AS YLAN® TRIAMINO from Degussa), N- (n-butyl-3-aminopropyltrimethoxysilanes, 3-aminopropylmethyldiethoxysilanes.
  • the coating compositions in particular the silanes or siloxanes, are preferably added in molar ratios of mixed oxide nanoparticles to silane of from 1: 1 to 10: 1.
  • the amount of solvent in the deagglomeration is generally 80 to 90 wt .-%, based on the total amount of mixed oxide nanoparticles and solvent.
  • the deagglomeration by grinding and simultaneous modification with the coating agent is preferably carried out at temperatures of 20 to 150 0 C, more preferably at 20 to 9O 0 C.
  • the suspension is subsequently separated from the grinding beads.
  • the suspension can be heated to complete the reaction for up to 30 hours. Finally, the solvent is distilled off and the remaining residue is dried. It may also be advantageous to leave the modified mixed oxide nanoparticles in the solvent and to use the dispersion for other applications.
  • the coating oxide-modified mixed oxide nanoparticles prepared in this way can be incorporated into transparent surface finishes or coatings, thereby achieving improved scratch protection. Modification with the coating agents allows the mixed oxide nanoparticles to be readily dispersed in non-aqueous systems. In addition, the coatings show less clouding compared to layers containing unmodified nanoparticles. Examples:
  • Magnesium chloride mixture was crushed in a mortar, resulting in a coarse powder.
  • the powder was calcined in a rotary kiln at 1050 0 C.
  • the contact time in the hot zone was a maximum of 5 min.
  • a white powder was obtained whose grain distribution corresponded to the feed material.
  • An X-ray structure analysis shows that predominantly ⁇ -alumina is present.
  • the images of the SEM image taken showed crystallites in the range 10 - 80 nm (estimate from SEM image), which are present as agglomerates.
  • the residual chlorine content was only a few ppm.
  • Zirconia (stabilized with yttrium) and had a size of 0.3 mm.
  • Example 1 40 g of the oxide mixture (MgO-doped corundum) from Example 1 was suspended in 160 g of methanol and deagglomerated in a vertical stirred ball mill from Netzsch (type PE 075). After 3 hours, the suspension was separated from the beads and transferred to a round bottom flask with reflux condenser. To the suspension was added 40 g of trimethoxy-octylsilane and heated at reflux for 2 h. After removal of the solvent, the coated oxide mixture was isolated and dried in a drying oven for another 20 h at 110 0 C. The product thus obtained is identical to the sample from Example 1.
  • the oxide mixture MgO-doped corundum
  • Example 2 40 g of the oxide mixture (MgO-doped corundum) from Example 1 was suspended in 160 g of methanol and deagglomerated in a vertical stirred ball mill from Netzsch (type PE 075). After 2 h, 20 g of 3- (trimethoxysilyl) propyl methacrylate (Dynasilan Memo, Degussa) were added and the suspension was deagglomerated in the stirred ball mill for a further 2 h. Subsequently, the suspension was separated from the beads and transferred to a round bottom flask with reflux condenser. Reflux was continued for an additional 2 hours before the solvent was distilled off.
  • the oxide mixture MgO-doped corundum
  • Example 2 40 g of the oxide mixture (MgO-doped corundum) from Example 1 was suspended in 160 g of methanol and deagglomerated in a vertical stirred ball mill from Netzsch (type PE 075). After 2 h, 20 g
  • Example 5 40 g of the oxide mixture (doped with MgO corundum) from Example 1 was suspended in 160 g of acetone and disagglomerated in a vertical stirred ball mill from. Netzsch (type PE 075). After 2 h, 20 g of aminopropyltrimethoxysilane (Dynasilan Ammo, Degussa) were added and the suspension was deagglomerated in the stirred ball mill for a further 2 h. Subsequently, the suspension was separated from the beads and transferred to a round bottom flask with reflux condenser. Reflux was continued for an additional 2 hours before the solvent was distilled off.
  • Example 5 40 g of the oxide mixture (doped with MgO corundum) from Example 1 was suspended in 160 g of acetone and disagglomerated in a vertical stirred ball mill from. Netzsch (type PE 075). After 2 h, 20 g of aminopropyltrimethoxysilane (Dyna
  • Example 2 40 g of the oxide mixture (doped with MgO corundum) from Example 1 was suspended in 160 g of acetone and disagglomerated in a vertical stirred ball mill from. Netzsch (type PE 075). After 2 h, 20 g of glycidyltrimethoxysilane (Dynasilan Glymo, Degussa) were added and the suspension was deagglomerated for a further 2 hours in the recycle ball mill. Subsequently, the suspension was separated from the beads and transferred to a round bottom flask with reflux condenser. Reflux was continued for an additional 2 hours before the solvent was distilled off.
  • glycidyltrimethoxysilane Dynasilan Glymo, Degussa
  • Example 2 40 g of the oxide mixture (MgO doped corundum) from Example 1 was suspended in 160 g of n-butanol and disagglomerated in a vertical stirred ball mill from Netzsch (type PE 075). After 2 h, a mixture of 5 g of aminopropyltrimethoxysilane (Dynasilan Glymo; Degussa) and 15 g of octyltriethoxysilane was added and the suspension was deagglomerated in the stirred ball mill for a further 2 h. The suspension remains stable for weeks without evidence of sedimentation of the coated mixed oxide.
  • the oxide mixture MgO doped corundum

Abstract

The invention relates to mixed oxide nanoparticles from aluminum oxide or oxides of the elements of the first and second main group of the periodic system. These mixed oxide nanoparticles are surface-modified with a coating agent, preferably a silane or siloxane.

Description

Beschreibung description
Oberflächenmodifizierte Nanopartikel aus Aluminiumoxid und Oxiden von Elementen der I. und II. Hauptgruppe des Periodensystems sowie deren HerstellungSurface-modified nanoparticles of aluminum oxide and oxides of elements of the I. and II. Main group of the Periodic Table and their preparation
Die vorliegende Erfindung betrifft oberflächenmodifizierte Nanopartikel, sowie deren Herstellung, wobei die Nanopartikel aus AI2O3 mit Anteilen von Oxiden der Elemente der I. und II. Hauptgruppe des Periodensystems bestehen.The present invention relates to surface-modified nanoparticles, and their preparation, wherein the nanoparticles consist of Al 2 O 3 with fractions of oxides of the elements of the I. and II. Main group of the Periodic Table.
Feine Aluminiumoxidpulver werden insbesondere für keramische Anwendungen, zur Matrixverstärkung organischer oder metallischer Schichten, als Füllstoffe, Polierpulver, für die Herstellung von Schleifmittel, als Additive in Lacken und Laminaten sowie für weitere Spezialanwendungen eingesetzt. Für den Einsatz in Laminaten werden die Aluminiumoxidpulver häufig noch mit Silanen oberflächenmodifiziert, um eine bessere Adaption an die Harzschichten zu erreichen. Es wird dabei sowohl die Haftung als auch die optische Eigenschaft verbessert. Dies äußert sich dann in einer Abnahme der Trübung. Bekannt ist auch ein mit Silan modifiziertes pyrogenes Aluminiumoxid für den Einsatz in Tonern (DE 42 02 694).Fine alumina powders are used in particular for ceramic applications, for matrix reinforcement of organic or metallic layers, as fillers, polishing powders, for the production of abrasives, as additives in paints and laminates as well as for other special applications. For use in laminates, the alumina powders are often surface-modified with silanes for better adaptation to the resin layers. Both the adhesion and the optical property are improved. This manifests itself in a decrease in turbidity. Also known is a silane-modified fumed alumina for use in toners (DE 42 02 694).
Nanopartikel aus AI2O3, deren Oberfläche mit Silanen modifiziert ist, sind in WO 02/051376 beschrieben. Bei deren Herstellung geht man von einem handelsüblichen AI2O3 aus, das dann mit einem Silan behandelt wird. Herstellung der Nanopartikel und deren Modifizierung erfolgen somit in zwei separaten Schritten. Handelsüblicher Nanokorund (0C-AI2O3) liegt als Pulver vor. Bedingt durch die hohe Oberflächenenergie lagern sich jedoch Nanopartikel immer zu größeren Agglomeraten zusammen, so dass es sich in Wirklichkeit nicht um echte Nanopartikel handelt. Dementsprechend groß sind auch die mit Silanen beschichteten Partikel gemäß WO 02/051 376.Nanoparticles of Al 2 O 3 whose surface is modified with silanes are described in WO 02/051376. In their preparation, one starts from a commercially available Al 2 O 3 , which is then treated with a silane. Production of the nanoparticles and their modification are thus carried out in two separate steps. Commercially available nanocorundum (0C-Al 2 O 3 ) is present as a powder. Due to the high surface energy, however, nanoparticles always accumulate to form larger agglomerates, so that in reality they are not true nanoparticles. Accordingly, the particles coated with silanes according to WO 02/051 376 are correspondingly large.
EP 1 123 354 (IOM Leipzig) beschreibt polymerisierbare Metalloxidpartikel, die mit verschiedenen Verbindungen modifiziert sind, welche eine reaktionsfähige, funktionelle Gruppe tragen. Als derartige modifizierbare Verbindungen kommen auch Silane infrage. Als Metalloxidpartikel werden hier ausschließlich Oxide eines Metalls oder Halbmetalls der dritten bis sechsten Hauptgruppe, der ersten bis achten Nebengruppe des Periodensystems oder der Lanthaniden eingesetzt, Mischoxide mit einem Anteil an Oxiden der ersten und zweiten Hauptgruppe sind nicht beschrieben.EP 1 123 354 (IOM Leipzig) describes polymerisable metal oxide particles which are modified with various compounds which have a reactive, wear functional group. Suitable modifiable compounds include silanes. The metal oxide particles here exclusively oxides of a metal or metalloid of the third to sixth main group, the first to eighth subgroup of the periodic table or the lanthanides are used, mixed oxides with a proportion of oxides of the first and second main groups are not described.
WO 2004/069400 (InM Saarbrücken) beschreibt ein Verfahren zur Herstellung eines Funktionskolloids, bei dem Partikel in einem Dispergiermittel in Anwesenheit eines Modifizierungsmittels mechanisch reaktiv zerkleinert werden, so dass das Modifizierungsmittel zumindest teilweise an die zerkleinerten Kolloidpartikel chemisch gebunden ist. Dieses Verfahren geht aus von homogenen Partikeln, die Desagglomeration von Agglomeraten aus bereits vorhandenen Nanopartikeln ist nicht offenbart.WO 2004/069400 (InM Saarbrücken) describes a process for the preparation of a functional colloid, in which particles are mechanically comminuted in a dispersant in the presence of a modifier, so that the modifier is at least partially chemically bound to the comminuted colloid particles. This method is based on homogeneous particles, the deagglomeration of agglomerates from existing nanoparticles is not disclosed.
US 6 896 958 B1 (Nanophase) beschreibt ein Verfahren, bei dem nanokristalline Stoffe aus der Gruppe der keramischen oder metallischen Stoffe in einem Lösungsmittel dispergiert und mit Siloxanen versetzt. Die erhaltenen Dispersionen werden in vernetzbaren Harzen zur Verbesserung der Kratzfestigkeit eingesetzt.No. 6,896,958 B1 (nanophase) describes a process in which nanocrystalline substances from the group of ceramic or metallic substances are dispersed in a solvent and treated with siloxanes. The resulting dispersions are used in crosslinkable resins to improve the scratch resistance.
Überraschend wurde nun gefunden, dass sich oberflächenmodifizierte Nanopartikel in Form von Mischoxiden aus AI2O3, mit einem Gehalt an Oxiden von Elementen aus der ersten und zweiten Hauptgruppe des Periodensystems durch Desagglomeration von Agglomeraten dieser Mischoxide in einem Lösungsmittel unter Zugabe eines Beschichtungsmittels besonders leicht herstellen lassen. Als Beschichtungsmittel werden bevorzugt Silane oder Siloxane eingesetzt.Surprisingly, it has now been found that surface-modified nanoparticles in the form of mixed oxides of Al 2 O 3 , containing oxides of elements from the first and second main groups of the Periodic Table, are particularly easy to produce by deagglomeration of agglomerates of these mixed oxides in a solvent with the addition of a coating agent to let. The coating agents used are preferably silanes or siloxanes.
Gegenstand der Erfindung sind oberflächenmodifizierte Nanopartikel bestehend aus 50 - 99,9 Gew.-% Aluminiumoxid und 0,1 - 50 Gew.-% Oxiden von Elementen der I. oder II. Hauptgruppe des Periodensystems, wobei diese Nanopartikel mit einem Beschichtungsmittel an der Oberfläche modifiziert sind. Das Aluminiumoxid in diesen Mischoxiden liegt bevorzugt zum überwiegenden Teil in der rhomboedrischen α-Modifikation (Korund) vor. Die Mischoxide gemäß der vorliegenden Erfindung haben vorzugsweise eine Kristall itgröße von kleiner 1 μm, bevorzugt kleiner 0,2 μm und besonders bevorzugt zwischen 0,001 und 0,09 μm. Erfindungsgemäße Partikel dieser Größenordnung sollen im folgenden als Mischoxid-Nanopartikel bezeichnet werden. Die erfindungsgemäßen Mischoxid-Nanopartikel können nach unterschiedlichen, im Folgenden beschriebenen Verfahren hergestellt werden. Diese Verfahrensbeschreibungen beziehen sich auf die Herstellung nur von reinen Aluminiumoxid-Partikeln, es versteht sich aber von selbst, dass bei all diesen Verfahrensvarianten neben Al-enthaltenden Ausgangsverbindungen auch solche Verbindungen aus Elementen der I. oder II. Hauptgruppe des Periodensystems anwesend sein müssen, um die erfindungsgemäßen Mischoxide zu bilden. Hierfür kommen vor allem infrage vorzugsweise die Chloride, aber auch die Oxide, Oxichloride, Carbonate, Sulfate oder andere geeignete Salze. Die Menge an solchen Oxidbildnern ist so bemessen, dass die fertigen Nanopartikel die zuvor genannten Mengen an Oxid MeO enthalten.The invention relates to surface-modified nanoparticles consisting of 50-99.9% by weight of aluminum oxide and 0.1-50% by weight of oxides of elements of the 1st or 2nd main group of the Periodic Table, these nanoparticles having a coating agent on the surface are modified. The alumina in these mixed oxides is preferably present for the most part in the rhombohedral α-modification (corundum). The mixed oxides according to the present invention preferably have a crystal it size of less than 1 micron, preferably less than 0.2 microns and more preferably between 0.001 and 0.09 microns. Particles of this size according to the invention will be referred to below as mixed oxide nanoparticles. The mixed oxide nanoparticles according to the invention can be prepared by different processes described below. These process descriptions refer to the production of pure alumina particles, but it goes without saying that in all these process variants in addition to Al-containing starting compounds and those compounds from elements of the I. or II. Main group of the Periodic Table must be present to form the mixed oxides according to the invention. For this purpose, especially the chlorides, but also the oxides, oxychlorides, carbonates, sulfates or other suitable salts come into question. The amount of such oxide formers is such that the finished nanoparticles contain the aforementioned amounts of oxide MeO.
Ganz allgemein geht man bei der Herstellung der erfindungsgemäßen Nanopartikel von größeren Agglomeraten dieser Mischoxide aus, die anschließend auf die gewünschte Partikelgröße desagglomeriert werden. Diese Agglomerate können hergestellt werden durch nachfolgend beschriebene Verfahren.Quite generally, in the preparation of the nanoparticles according to the invention, larger agglomerates of these mixed oxides are used, which are then deagglomerated to the desired particle size. These agglomerates can be prepared by methods described below.
Solche Agglomerate lassen sich beispielsweise durch verschiedene chemische Synthesen herstellen. Hierbei handelt es sich meist um Fällungsreaktionen (Hydroxidfällung, Hydrolyse metallorganischer Verbindungen) mit anschließender Kalzinierung. Dabei werden häufig Kristallisationskeime zugesetzt, um die Umwandlungstemperatur zum α-Aluminiumoxid herabzusetzen. Die so erhaltenen Sole werden getrocknet und dabei in ein Gel überführt. Die weitere Kalzinierung findet dann bei Temperaturen zwischen 3500C und 6500C statt. Für die Umwandlung zum Ct-AI2O3 muss dann bei Temperaturen um 10000C geglüht werden. Die Verfahren sind ausführlich in DE 199 22 492 beschrieben. Ein weiterer Weg ist das Aerosolverfahren. Dabei werden die gewünschten Moleküle aus chemischen Reaktionen eines Precursorgases oder durch schnelle Abkühlung eines übersättigten Gases erhalten. Die Bildung der Partikel erfolgt entweder durch Kollision oder die ständige im Gleichgewicht befindliche Verdampfung und Kondensation von Molekülclustern. Die neu gebildeten Teilchen wachsen durch weitere Kollision mit Produktmolekülen (Kondensation) und/oder Partikeln (Koagulation). Ist die Koagulationsrate größer als jene der Neubildung bzw. des Wachstums, entstehen Agglomerate von kugelförmigen Primärpartikeln.Such agglomerates can be prepared, for example, by various chemical syntheses. These are usually precipitation reactions (hydroxide precipitation, hydrolysis of organometallic compounds) with subsequent calcination. Crystallization seeds are often added to reduce the transition temperature to the α-alumina. The sols thus obtained are dried and thereby converted into a gel. The further calcination then takes place at temperatures between 350 0 C and 650 0 C. For the conversion to Ct-Al 2 O 3 must then be annealed at temperatures around 1000 0 C. The processes are described in detail in DE 199 22 492. Another way is the aerosol process. The desired molecules are obtained from chemical reactions of a Precursorgases or by rapid cooling of a supersaturated gas. The formation of the particles occurs either through collision or the constant equilibrium evaporation and condensation of molecular clusters. The newly formed particles grow by further collision with product molecules (condensation) and / or particles (coagulation). If the coagulation rate is greater than that of the new growth or growth, agglomerates of spherical primary particles are formed.
Flammenreaktoren stellen eine auf diesem Prinzip basierendeFlame reactors are based on this principle
Herstellungsvariante dar. Nanopartikel werden hier durch die Zersetzung von Precursormolekülen in der Flamme bei 15000C - 25000C gebildet. Als Beispiele seien die Oxidationen von TiCU; SICU und SJ2O(CH3)Θ in Methan/θ2-Flammen erwähnt, die zu TiO2- und Siθ2-Partikeln führen. Bei Einsatz von AICb konnte bislang nur die entsprechende Tonerde erzeugt werden. Flammenreaktoren werden heute großtechnisch für die Synthese von Submikropartikeln wie Ruß, Pigment-Tiθ2, Kieselsäure und Tonerde eingesetzt.Manufacturing variant dar. Nanoparticles are formed here by the decomposition of Precursormolekülen in the flame at 1500 0 C - 2500 0 C. As examples, the oxidations of TiCU; SICU and SJ2O (CH3) Θ in methane / θ 2 flames leading to TiO 2 and SiO 2 particles. When using AICb so far only the corresponding clay could be produced. Flame reactors are now used industrially for the synthesis of submicroparticles such as carbon black, pigment Tiθ2, silica and alumina.
Kleine Partikel können auch mit Hilfe von Fliehkraft, Druckluft, Schall, Ultraschall und weiteren Methoden auch aus Tropfen gebildet werden. Die Tropfen werden dann durch direkte Pyrolyse oder durch in situ Reaktionen mit anderen Gasen in Pulver umgewandelt. Als bekannte Verfahren sind die Sprüh- und Gefriertrocknung zu erwähnen. Bei der Spraypyrolyse werden Precursortropfen durch ein Hochtemperaturfeld (Flamme, Ofen) transportiert, was zu einer raschen Verdampfung der leicht flüchtigen Komponente führt oder die Zersetzungsreaktion zum gewünschten Produkt initiiert. Die gewünschten Partikel werden in Filtern gesammelt. Als Beispiel kann hier die Herstellung von BaTiθ3 aus einer wässrigen Lösung von Bariumacetat und Titanlactat genannt werden.Small particles can also be formed from drops with the help of centrifugal force, compressed air, sound, ultrasound and other methods. The drops are then converted into powder by direct pyrolysis or by in situ reactions with other gases. As known methods, the spray and freeze drying should be mentioned. In spray pyrolysis, precursor drops are transported through a high temperature field (flame, oven), resulting in rapid evaporation of the volatile component or initiating the decomposition reaction to the desired product. The desired particles are collected in filters. As an example, the production of BaTiO 3 from an aqueous solution of barium acetate and titanium lactate can be mentioned here.
Durch Mahlung kann ebenfalls versucht werden, Korund zu zerkleinern und dabei Kristallite im nano-Bereich zu erzeugen. Die besten Mahlergebnisse können mit Rührwerkskugelmühlen in einer Nassmahlung erzielt werden. Dabei müssen Mahlperlen aus einem Material verwendet werden, das eine größere Härte als Korund hat.By grinding can also be attempted to crush corundum and thereby produce crystallites in the nano range. The best grinding results can be achieved with stirred ball mills in a wet grinding. It must Grinding beads are used made of a material that has a greater hardness than corundum.
Ein weiterer Weg zur Herstellung von Korund bei niedriger Temperatur stellt die Umwandlung von Aluminiumchlorohydrat dar. Dieses wird dazu ebenfalls mit Impfkeimen, bevorzugt aus Feinstkorund oder Hämatit, versetzt. Zur Vermeidung von Kristallwachstum müssen die Proben bei Temperaturen um 7000C bis maximal 9000C kaliziniert werden. Die Dauer der Kalzinierung beträgt hierbei mindestens vier Stunden. Nachteil dieser Methode ist deshalb der große Zeitaufwand und die Restmengen an Chlor im Aluminiumoxid. Die Methode wurde ausführlich beschrieben in Ber. DKG 74 (1997) No. 11/12, S. 719 - 722.Another way to produce corundum at low temperature is the conversion of aluminum chlorohydrate. This is also to seed with added, preferably from Feinstkorund or hematite. To avoid crystal growth, the samples at temperatures around 700 0 C to a maximum of 900 0 C must be kaliziniert. The duration of the calcination is at least four hours. Disadvantage of this method is therefore the large amount of time and the residual amounts of chlorine in the alumina. The method has been described in detail in Ber. DKG 74 (1997) no. 11/12, p. 719-722.
Aus diesen Agglomeraten müssen die Nanopartikel freigesetzt werden. Dies geschieht vorzugsweise durch Mahlen oder durch Behandlung mit Ultraschall. Erfindungsgemäß erfolgt diese Desagglomeration in Gegenwart einesFrom these agglomerates, the nanoparticles must be released. This is preferably done by grinding or by treatment with ultrasound. According to the invention, this deagglomeration takes place in the presence of a
Lösungsmittels und eines Beschichtungsmittels, bevorzugt eines Silans, das während des Mahlprozesses die entstehenden aktiven und reaktiven Oberflächen durch eine chemische Reaktion oder physikalische Anlagerung absättigt und somit die Reagglomeration verhindert. Das nano-Mischoxid bleibt als kleines Partikel erhalten. Es ist auch möglich, das Beschichtungsmittel nach erfolgter Desagglomeration zuzugeben.Solvent and a coating agent, preferably a silane, which saturates the resulting active and reactive surfaces by a chemical reaction or physical attachment during the milling process and thus prevents reagglomeration. The nano-mixed oxide remains as a small particle. It is also possible to add the coating agent after deagglomeration.
Vorzugsweise geht man bei der erfindungsgemäßen Herstellung der Mischoxide von Agglomeraten aus, die entsprechend den Angaben in Ber. DKG 74 (1997) No. 11/12, S. 719 - 722 hergestellt werden, wie zuvor beschrieben.Preferably, in the preparation of the mixed oxides according to the invention, agglomerates are used which, as described in Ber. DKG 74 (1997) no. 11/12, pp. 719-722, as previously described.
Ausgangspunkt hierbei ist Aluminiumchlorohydrat, dem die Formel AI2(OH)xCIy zukommt, wobei x eine Zahl von 2,5 bis 5,5 und y eine Zahl von 3,5 und 0,5 ist und die Summe von x und y stets 6 beträgt. Dieses Aluminiumchlorohydrat wird als wässrige Lösung mit Kristallisationskeimen vermischt, anschließend getrocknet und dann einer thermischen Behandlung (Kalzinierung) unterzogen. Bevorzugt geht man dabei von ca. 50 %igen wässrigen Lösungen aus, wie sie kommerziell verfügbar sind. Eine solche Lösung wird mit Kristallisationskeimen versetzt, die die Bildung der α-Modifikation des AI2O3 fördern. Insbesondere bewirken solche Keime eine Herabsetzung der Temperatur für die Bildung der α- Modifikation bei der nachfolgenden thermischen Behandlung. Als Keime kommen bevorzugt infrage feinstdisperser Korund, Diaspor oder Hämatit. Besonders bevorzugt nimmt man feinstdisperse α- Al2θ3-Keime mit einer mittleren Teilchengröße von weniger als 0,1 μm. Im Allgemeinen reichen 2 bis 3 Gew.-% an Keimen bezogen auf das entstehende Aluminiumoxid aus.The starting point here is aluminum chlorohydrate, which has the formula Al 2 (OH) x Cl y , where x is a number from 2.5 to 5.5 and y is a number from 3.5 to 0.5 and the sum of x and y always 6. This aluminum chlorohydrate is mixed with crystallization seeds as an aqueous solution, then dried and then subjected to a thermal treatment (calcination). Preference is given to starting from about 50% aqueous solutions, as they are commercially available. Such a solution is mixed with nuclei which promote the formation of the α-modification of Al 2 O 3 . In particular, such nuclei cause a lowering of the temperature for the formation of the α-modification in the subsequent thermal treatment. As germs are preferably in question finely disperse corundum, diaspore or hematite. Particular preference is given to taking very finely divided α-Al 2 O 3 nuclei having an average particle size of less than 0.1 μm. In general, 2 to 3 wt .-% of germs based on the resulting alumina from.
Diese Ausgangslösung enthält zusätzlich noch Oxidbildner, um die Oxide MeO in dem Mischoxid zu erzeugen. Hierfür kommen vor allem infrage die Chloride der Elemente der I. und II. Hauptgruppe des Periodensystems, insbesondere die Chloride der Elemente Ca und Mg, aber darüber hinaus auch andere lösliche oder dispergierbare Salze wie Oxide, Oxichloride, Carbonate oder Sulfate. Die Menge an Oxidbildner ist so bemessen, dass die fertigen Nanopartikel 0,01 bis 50 Gew.- % des Oxids MeO enthalten. Die Oxide der I. und II. Hauptgruppe können als separate Phase neben dem Aluminiumoxid vorliegen oder mit diesem echte Mischoxide wie z.B. Spinelle etc. bilden. Der Begriff "Mischoxide" im Rahmen dieser Erfindung ist so zu verstehen, dass er beide Typen mit einschließt.This starting solution additionally contains oxide formers in order to produce the oxides MeO in the mixed oxide. For this purpose, especially the chlorides of the elements of the I. and II. Main group of the Periodic Table, in particular the chlorides of the elements Ca and Mg, but also other soluble or dispersible salts such as oxides, oxychlorides, carbonates or sulfates. The amount of oxide generator is such that the finished nanoparticles contain 0.01 to 50% by weight of the oxide MeO. The oxides of I. and II. Main group may be present as a separate phase in addition to the alumina or with this real mixed oxides such. Form spinels etc. The term "mixed oxides" in the context of this invention should be understood to include both types.
Diese Suspension aus Aluminiumchlorohydrat, Keimen und Oxidbildnern wird dann bis zum Trocknen eingedampft und einer thermischen Behandlung (Kalzinierung) unterworfen. Diese Kalzinierung erfolgt in hierfür geeigneten Vorrichtungen, beispielsweise in Durchschub-, Kammer-, Rohr-, Drehrohr- oder Mikrowellenöfen oder in einem Wirbelschichtreaktor. Gemäß einer Variante des erfindungsgemäßen Verfahrens kann man auch so vorgehen, dass man die wässrige Suspension aus Aluminiumchlorohydrat, Oxidbildnern und Keimen ohne vorherige Entfernung des Wassers direkt in die Kalzinierungsapparatur einspritzt.This suspension of aluminum chlorohydrate, germs and oxide formers is then evaporated to dryness and subjected to a thermal treatment (calcination). This calcination is carried out in suitable devices, for example in push-through, chamber, tube, rotary kiln or microwave ovens or in a fluidized bed reactor. According to a variant of the method according to the invention, it is also possible to inject the aqueous suspension of aluminum chlorohydrate, oxide formers and germs directly into the calcining apparatus without prior removal of the water.
Die Temperatur für die Kalzinierung soll 14000C nicht übersteigen. Die untere Temperaturgrenze ist abhängig von der gewünschten Ausbeute an nanokristallinem Mischoxid, vom gewünschten Restchlorgehalt und dem Gehalt an Keimen. Die Bildung der Nanopartikel setzt bereits bei ca. 5000C ein, um jedoch den Chlorgehalt niedrig und die Ausbeute an Nanopartikeln hoch zu halten, wird man jedoch bevorzugt bei 700 bis 11000C, insbesondere bei 1000 bis 11000C arbeiten.The temperature for the calcination should not exceed 1400 0 C. The lower temperature limit depends on the desired yield of nanocrystalline mixed oxide, the desired residual chlorine content and the content of Germinate. The formation of the nanoparticles begins at about 500 0 C, but to keep the chlorine content low and the yield of nanoparticles high, but you will work preferably at 700 to 1100 0 C, in particular at 1000 to 1100 0 C.
Es hat sich überraschend herausgestellt, dass für die Kalzinierung im Allgemeinen 0,5 bis 30 Minuten, vorzugsweise 0,5 bis 10, insbesondere 2 bis 5 Minuten ausreichen. Bereits nach dieser kurzen Zeit kann unter den oben angegebenen Bedingungen für die bevorzugten Temperaturen eine ausreichende Ausbeute an Nanopartikeln erreicht werden. Man kann jedoch auch entsprechend den Angaben in Ber. DKG 74 (1997) No. 11/12, S. 722 4 Stunden lang bei 700°C oder 8 Stunden lang bei 5000C kalzinieren.It has surprisingly been found that for the calcination 0.5 to 30 minutes, preferably 0.5 to 10, in particular 2 to 5 minutes are generally sufficient. Already after this short time under the conditions given above for the preferred temperatures, a sufficient yield of nanoparticles can be achieved. However, one can also according to the information in Ber. DKG 74 (1997) no. 11/12, p. 722 calcining for 4 hours at 700 ° C or 8 hours at 500 0 C.
Bei der Kalzinierung fallen Agglomerate in Form von nahezu kugelförmigen Nanopartikeln an. Diese Partikel bestehen aus AI2O3 und MeO. Der Gehalt an MeO wirkt als Inhibitor für das Kristallwachstum und hält die Kristallitgröße klein. Dadurch unterscheiden sich die Agglomerate, wie sie durch die oben beschriebene Kalzinierung erhalten werden, deutlich von den Partikeln, wie sie bei dem in WO 2004/069 400 beschriebenen Verfahren eingesetzt werden, wo es sich um gröbere, in sich homogene Teilchen und nicht um Agglomerate von bereits vorgefertigten Nanopartikeln handelt.During calcination, agglomerates accumulate in the form of nearly spherical nanoparticles. These particles consist of Al 2 O 3 and MeO. The content of MeO acts as an inhibitor of crystal growth and keeps the crystallite size small. As a result, the agglomerates, as obtained by the calcination described above, clearly differ from the particles used in the process described in WO 2004/069 400, which are coarser, inherently homogeneous particles and not agglomerates of pre-fabricated nanoparticles.
Zur Gewinnung von Nanopartikeln werden die Agglomerate vorzugsweise durch Nassmahlung in einem Lösungsmittel zerkleinert, beispielsweise in einer Attritormühle, Perlmühle oder Rührwerksmühle. Dabei erhält man Mischoxid- Nanopartikel, die eine Kristallitgröße von kleiner 1 μm, bevorzugt kleiner 0,2 μm, besonders bevorzugt zwischen 0,001 und 0,9 μm aufweisen. So erhält man beispielsweise nach einer sechsstündigen Mahlung eine Suspension von Nanopartikeln mit einem d90-Wert von ungefähr 50 nm. Eine andere Möglichkeit der Desagglomeration ist die Beschallung mit Ultraschall.To obtain nanoparticles, the agglomerates are preferably comminuted by wet grinding in a solvent, for example in an attritor mill, bead mill or stirred mill. This gives mixed oxide nanoparticles which have a crystallite size of less than 1 μm, preferably less than 0.2 μm, more preferably between 0.001 and 0.9 μm. For example, after six hours of grinding, a suspension of nanoparticles with a d90 value of approximately 50 nm is obtained. Another possibility for deagglomeration is sonication.
Für die erfindungsgemäße Modifizierung der Oberfläche dieser Nanopartikel mit Beschichtungsmitteln, wie z. B. Silanen oder Siloxanen gibt es zwei Möglichkeiten. Gemäß der ersten bevorzugten Variante kann man die Desagglomeration in Gegenwart des Beschichtungsmittels vornehmen, beispielsweise indem man das Beschichtungsmittel während des Mahlens in die Mühle gibt. Eine zweite Möglichkeit besteht darin, dass man zuerst die Agglomerate der Nanopartikel zerstört und anschließend die Nanopartikel, vorzugsweise in Form einer Suspension in einem Lösungsmittel, mit dem Beschichtungsmittel behandelt.For the inventive modification of the surface of these nanoparticles with coating agents such. As silanes or siloxanes there are two possibilities. According to the first preferred variant, the deagglomeration in Make the presence of the coating agent, for example by adding the coating agent during grinding in the mill. A second possibility consists of first destroying the agglomerates of the nanoparticles and then treating the nanoparticles, preferably in the form of a suspension in a solvent, with the coating agent.
Als Lösungsmittel für die Desagglomeration kommen in Frage sowohl Wasser als auch übliche Lösungsmittel, vorzugsweise solche, die auch in der Lackindustrie genommen werden, wie zum Beispiel C-i-C-i-Alkohole, insbesondere Methanol, Ethanol oder Isopropanol, Aceton, Tetrahydrofuran, Butylacetat. Erfolgt die Desagglomeration in Wasser, sollte eine anorganische oder organische Säure, beispielsweise HCl, HNO3, Ameisensäure oder Essigsäure zugegeben werden, um die entstehenden Nanopartikel in der wässrigen Suspension zu stabilisieren. Die Menge an Säure kann 0,1 bis 5 Gew.-%, bezogen auf das Mischoxid, betragen. Aus dieser wässrigen Suspension der sauer modifizierten Nanopartikel wird dann bevorzugt die Kornfraktion mit einem Teilchendurchmesser von weniger als 20 nm durch Zentrifugieren abgetrennt. Anschließend wird bei erhöhter Temperatur, beispielsweise bei ca. 1000C das Beschichtungsmittel, vorzugsweise ein Silan oder Siloxan, zugegeben. Die so behandelten Nanopartikel fallen aus, werden abgetrennt und zu einem Pulver getrocknet, beispielsweise durch Gefriertrocknung.Suitable solvents for deagglomeration are both water and customary solvents, preferably those which are also used in the paint industry, such as, for example, C 1 -C 4 -alcohols, in particular methanol, ethanol or isopropanol, acetone, tetrahydrofuran, butyl acetate. When deagglomerating in water, an inorganic or organic acid such as HCl, HNO 3 , formic acid or acetic acid should be added to stabilize the resulting nanoparticles in the aqueous suspension. The amount of acid may be 0.1 to 5 wt .-%, based on the mixed oxide. From this aqueous suspension of the acid-modified nanoparticles is then preferably the grain fraction having a particle diameter of less than 20 nm separated by centrifugation. Subsequently, at elevated temperature, for example at about 100 ° C., the coating agent, preferably a silane or siloxane, is added. The nanoparticles thus treated precipitate, are separated and dried to a powder, for example by freeze-drying.
Als geeignete Beschichtungsmittel kommen hierbei vorzugsweise Silane oder Siloxane oder deren Mischungen infrage.Suitable coating agents here are preferably silanes or siloxanes or mixtures thereof.
Darüber hinaus sind als Beschichtungsmittel alle Stoffe geeignet, die an der Oberfläche der Mischoxide physikalisch anbinden können (Adsorption) oder die durch die Bildung einer chemischen Bindung an der Oberfläche der Mischoxid- Partikel anbinden können. Da die Oberfläche der Mischoxid-Partikel hydrophil ist und freie Hydroxygruppen zur Verfügung stehen, kommen als Beschichtungsmittel Alkohole, Verbindungen mit Amino-, Hydroxy-, Carbonyl-, Carboxyl- oder Mercapto-Funktionen, Silane oder Siloxane infrage. Beispiele für solche Beschichtungsmittel sind Polyvinylalkohol, Mono-, Di- und Tricarbonsäuren, Aminosäuren, Amine, Wachse, Tenside, Hydroxycarbonsäuren, Organosilane und Organosiloxane.In addition, suitable coating agents are all substances which can bind physically to the surface of the mixed oxides (adsorption) or which can bond to form a chemical bond on the surface of the mixed oxide particles. Since the surface of the mixed oxide particles is hydrophilic and free hydroxy groups are available, suitable coating agents are alcohols, compounds having amino, hydroxyl, carbonyl, carboxyl or mercapto functions, silanes or siloxanes. Examples of such coating compositions are polyvinyl alcohol, mono-, di- and tricarboxylic acids, Amino acids, amines, waxes, surfactants, hydroxycarboxylic acids, organosilanes and organosiloxanes.
Als Silane bzw. Siloxane kommen infrage Verbindungen der FormelnSuitable silanes or siloxanes are compounds of the formulas
a) R [-Si (R'R")-O-]n Si (R1R11J-R1" oder cyclo-[-Si (R'R")-O-]r Si (R1R11J-O-a) R [-Si (R'R ") - O-] n Si (R 1 R 11 JR 1 " or cyclo - [-Si (R'R ") - O-] r Si (R 1 R 11 JO -
worinwherein
R, R', R", R1"- gleich oder verschieden voneinander einen Alkylrest mit 1 - 18 C- Atomen oder einen Phenylrest oder einen Alkylphenyl- oder einen Phenylalkylrest mit 6 - 18 C-Atomen oder einen Rest der allgemeinen Formel -(CmH2m-O)p-CqH2q+i oder einen Rest der allgemeinen Formel -C3H2sY oder einen Rest der allgemeinen Formel -XZn,R, R ', R ", R 1 " - identical or different from each other, an alkyl radical having 1-18 C atoms or a phenyl radical or an alkylphenyl or a phenylalkyl radical having 6 - 18 C-atoms or a radical of the general formula - ( C m H 2m -O) pC q H 2 q + i or a radical of the general formula -C 3 H 2s Y or a radical of the general formula -XZn,
n eine ganze Zahl mit der Bedeutung 1 < n ≤ 1000, bevorzugt 1 < n < 100, m eine ganze Zahl 0 ≤ m ≤ 12 und p eine ganze Zahl 0 ≤ p ≤ 60 und q eine ganze Zahl 0 < q ≤ 40 und r eine ganze Zahl 2 < r ≤ 10 und s eine ganze Zahl 0 ≤ s ≤ 18 undn is an integer meaning 1 <n ≦ 1000, preferably 1 <n <100, m is an integer 0 ≦ m ≦ 12 and p is an integer 0 ≦ p ≦ 60 and q is an integer 0 <q ≦ 40 and r is an integer 2 <r ≤ 10 and s is an integer 0 ≤ s ≤ 18 and
Y eine reaktive Gruppe, beispielsweise α,ß-ethylenisch ungesättigte Gruppen, wie (Meth)Acryloyl-, Vinyl- oder Allylgruppen, Amino-, Amido-, Ureido-, Hydroxyl-, Epoxy-, Isocyanato-, Mercapto-, Sulfonyl-, Phosphonyl-, Trialkoxylsilyl-, Alkyldialkoxysilyl-, Dialkylmonoalkoxysilyl-, Anhydrid- und/oder Carboxylgruppen, Imido-, Imino-, Sulfit-, Sulfat-, Sulfonat-, Phosphin-, Phosphit-, Phosphat-, Phosphonatgruppen und X ein t-funktionelles Oligomer mit t eine ganze Zahl 2 < t ≤ 8 und Z wiederum einen RestY is a reactive group, for example α, β-ethylenically unsaturated groups, such as (meth) acryloyl, vinyl or allyl groups, amino, amido, ureido, hydroxyl, epoxy, isocyanato, mercapto, sulfonyl, Phosphonyl, trialkoxylsilyl, alkyldialkoxysilyl, dialkylmonoalkoxysilyl, anhydride and / or carboxyl groups, imido, imino, sulfite, sulfate, sulfonate, phosphine, phosphite, phosphate, phosphonate groups, and X is a t-functional Oligomer with t an integer 2 <t ≤ 8 and Z in turn a remainder
R [-Si (R1R11KHn Si (R1R11J-R1" oder cyclo-[-Si (R'R")-O-]r Si (R1R11J-O- darstellt, wie vorstehend definiert.R [-Si (R 1 R 11 KH n Si (R 1 R 11 JR 1 ") or cyclo - [-Si (R'R") - O-] r Si (R 1 R 11 JO- represents as defined above.
Das t-funktionelle Oligomer X ist dabei bevorzugt ausgewählt aus:The t-functional oligomer X is preferably selected from:
Oligoether, Oligoester, Oligoamid, Oligourethan, Oligoharnstoff, Oligoolefin,Oligoether, oligoester, oligoamide, oligourethane, oligourea, oligoolefin,
Oligovinylhalogenid, Oligovinylidendihalogenid, Oligoimin, Oligovinylalkohol, Ester, Acetal oder Ether von Oligovinylalkohol, Cooligomere von Maleinsäureanhydrid, Oligomere von (Meth)acrylsäure, Oligomere von (Meth)acrylsäureestem, Oligomere von (Meth)acrylsäureamiden, Oligomere von (Meth)acrylsäureimiden, Oligomere von (Meth)acrylsäurenitril, besonders bevorzugt Oligoether, Oligoester, Oligourethane.Oligovinyl halide, oligovinylidenedihalogenide, oligoimine, oligovinylalcohol, esters, acetal or ethers of oligovinyl alcohol, cooligomers of maleic anhydride, oligomers of (meth) acrylic acid, oligomers of (meth) acrylic acid esters, oligomers of (meth) acrylic acid amides, oligomers of (meth) acrylic acid imides, oligomers of (Meth) acrylonitrile, particularly preferably oligoether, oligoester, oligourethane.
Beispiele für Reste von Oligoethern sind Verbindungen vom Typ -(CaH2a-O)b- CaH2a- bzw. O-(CaH2a-O)b-CaH2a-O mit 2 < a < 12 und 1 < b < 60, z. B. ein Diethylenglykol-, Triethylenglykol- oder Tetraethylenglykol-Rest, ein Dipropylenglykol-, Tripropylenglykol-, Tetrapropylenglykol-Rest, ein Dibutylenglykol-, Tributylenglykol- oder Tetrabutylenglykol-Rest. Beispiele für Reste von Oligoestern sind Verbindungen vom Typ -CbH2b-(C(CO) CaH2a-(CO) O- CbH2b-)c- bzw. -O-CbH2b-(C(CO) CaH2a-(CO) O-CbH2b-)c-O- mit a und b unterschiedlich oder gleich 3 < a < 12, 3 < b < 12 und 1 < c < 30, z. B. ein Oligoester aus Hexandiol und Adipinsäure. b) Organosilane des Typs (RO)3Si(CH2)m-R' R = Alkyl, wie Methyl-, Ethyl-, Propyl- m = 0,1 - 20 R1 = Methyl-, Phenyl,Examples of radicals of oligoethers are compounds of the type - (C a H 2a -O) b - C a H 2a - or O- (C a H2a-O) b -CaH 2a -O with 2 <a <12 and 1 <b <60, z. A diethylene glycol, triethylene glycol or tetraethylene glycol residue, a dipropylene glycol, tripropylene glycol, tetrapropylene glycol residue, a dibutylene glycol, tributylene glycol or tetrabutylene glycol residue. Examples of residues of oligoesters are compounds of the type -C b H 2b - (C (CO) C a H 2 a- (CO) O- C b H 2b -) c- or -OC b H 2b - (C ( CO) C a H 2a - (CO) OC b H 2b -) c -O- with a and b different or equal to 3 <a <12, 3 <b <12 and 1 <c <30, z. B. an oligoester of hexanediol and adipic acid. b) organosilanes of the type (RO) 3 Si (CH 2 ) m -R 'R = alkyl, such as methyl, ethyl, propyl, m = 0.1-20 R 1 = methyl, phenyl,
-C4F9; OCF2-CHF-CF3, -C6Fi3, -0-CF2-CHF2 -C 4 F 9 ; OCF 2 -CHF-CF 3 , -C 6 Fi 3 , -O-CF 2 -CHF 2
-NH2, -N3, SCN, -CH=CH2, -NH-CH2-CH2-NH2,-NH 2 , -N 3 , SCN, -CH = CH 2 , -NH-CH 2 -CH 2 -NH 2 ,
-N-(CH2-CH2-NH2)2 -N- (CH 2 -CH 2 -NH 2 ) 2
-0OC(CH3)C = CH2 -OCH2-CH(O)CH2 -OCO (CH 3 ) C = CH 2 -OCH 2 -CH (O) CH 2
-NH-CO-N-CO-(CH2)5 -NH-CO-N-CO- (CH 2 ) 5
-NH-COO-CH3, -NH-COO-CH2-CH3, -NH-(CH2)3Si(OR)3 -NH-COO-CH 3 , -NH-COO-CH 2 -CH 3 , -NH- (CH 2 ) 3 Si (OR) 3
-Sx-(CH2)3)Si(OR)3 -SH-S x - (CH 2 ) 3 ) Si (OR) 3 SH
-NR1R11R"1 (R1 = Alkyl, Phenyl; R" = Alkyl, Phenyl; R"1 = H, Alkyl, Phenyl,-NR 1 R 11 R " 1 (R 1 = alkyl, phenyl; R" = alkyl, phenyl; R " 1 = H, alkyl, phenyl,
Benzyl,benzyl,
C2H4NR1"1 mit R1111 = A, Alkyl und R = H, Alkyl).C 2 H 4 NR 1 " 1 with R 1111 = A, alkyl and R = H, alkyl).
Beispiele für Silane der oben definierten Art sind z. B. Hexamethyldisiloxan, Octamethyltrisiloxan, weitere homologe und isomere Verbindungen der Reihe SinOn-1 (CH3)2n+2, wobei n eine ganze Zahl 2 < n < 1000 ist, z. B. Polydimethylsiloxan 200® fluid (2O cSt).Examples of silanes of the type defined above are, for. Hexamethyldisiloxane, octamethyltrisiloxane, other homologous and isomeric compounds of the series Si n O n-1 (CH 3 ) 2 n + 2, where n is an integer 2 <n <1000, e.g. B. Polydimethylsiloxane 200® fluid (2O cSt).
Hexamethyl-cyclo-trisiloxan, Octamethyl-cyclo-tetrasiloxan, weitere homologe und isomere Verbindungen der ReiheHexamethyl-cyclo-trisiloxane, octamethyl-cyclo-tetrasiloxane, other homologous and isomeric compounds of the series
(Si-O)r(CH3)2r. wobei r eine ganze Zahl 3 < r ≤ 12 ist,(Si-O) r (CH 3 ) 2r. where r is an integer 3 <r ≤ 12,
Dihydroxytetramethydisiloxan, Dihydroxyhexamethyltrisiloxan,Dihydroxytetramethydisiloxane, dihydroxyhexamethyltrisiloxane,
Dihydroxyoctamethyltetrasiloxan, weitere homologe und isomere Verbindungen der ReiheDihydroxyoctamethyltetrasiloxane, other homologous and isomeric compounds of the series
HO-[(Si-O)n(CH3)2n]-Si(CH3)2-OH oder HO-[(Si-O)n(CH3)2n]-[Si-O)m(C6H5)2m]-Si(CH3)2-OH, wobei m eine ganze Zahl 2 < m ≤ 1000 ist, bevorzugt sind die α,ω-Dihydroxypolysiloxane, z. B. PolydimethylsiloxanHO - [(Si-O) n (CH 3 ) 2 n] -Si (CH 3 ) 2 -OH or HO - [(Si-O) n (CH 3 ) 2n] - [Si-O) m (C 6 H 5 ) 2m] -Si (CH 3 ) 2-OH, where m is an integer 2 <m ≤ 1000, preferably the α, ω-dihydroxypolysiloxanes, z. B. polydimethylsiloxane
(OH-Endgruppen, 90-150 cST) oder Polydimethylsiloxan-co-diphenylsiloxan,(OH end groups, 90-150 cSt) or polydimethylsiloxane-co-diphenylsiloxane,
(Dihydroxy-Endgruppen, 60 cST). Dihydrohexamethytrisiloxan, Dihydrooctamethyltetrasiloxan weitere homologe und isomere Verbindungen der Reihe(Dihydroxy end groups, 60 cST). Dihydrohexamethytrisiloxane, Dihydrooctamethyltetrasiloxan other homologous and isomeric compounds of the series
H-[(Si-O)n(CH3)2n]-Si(CH3)2-H, wobei n eine ganze Zahl 2 < n ≤ 1000 ist, bevorzugt sind die α,ω-H - [(Si-O) n (CH 3 ) 2n ] -Si (CH 3 ) 2 -H, where n is an integer 2 <n ≦ 1000, preferably the α, ω-
Dihydropolysiloxane, z. B. Polydimethylsiloxan (Hydrid-Endgruppen, Mn = 580). Di(hydroxypropyl)hexamehtyltrisiloxan, Dihydroxypropyl)octamethyltetrasiloxan, weitere homologe und isomere Verbindungen der Reihe HO-(CH2)u[(Si-Dihydropolysiloxanes, e.g. B. polydimethylsiloxane (hydride end groups, M n = 580). Di (hydroxypropyl) hexamethyltrisiloxane, dihydroxypropyl) octamethyltetrasiloxane, other homologous and isomeric compounds of the series HO- (CH 2 ) u [(Si)
O)n(CH3)2(CH2)u-OH, bevorzugt sind die α,ω-Dicarbinolpolysiloxane mit 3 ≤ u <O) n (CH 3 ) 2 (CH 2 ) u -OH, preferred are the α, ω-dicarbinol polysiloxanes with 3 ≤ u <
18, 3 < n < 1000 oder ihre Polyether-modifizierten Nachfolgeverbindungen auf Basis der Ethylenoxid (EO) und Propylenoxid (PO) als Homo- oder Mischpolymer HO-(EO/PO)v-(CH2)u[(Si-O)t(CH3)2t]-Si(CH3)2(CH2)u-(EO/PO)v-OH, bevorzugt sind α,ω-Di(carbinolpolyether)-polysiloxane mit 3 < n ≤ 1000, 3 ≤ u ≤ 18, 1 < v ≤ 50.18, 3 <n <1000 or their polyether-modified successor compounds Base of ethylene oxide (EO) and propylene oxide (PO) as homo- or mixed polymer HO- (EO / PO) v - (CH 2 ) u [(Si-O) t (CH 3 ) 2t ] -Si (CH 3 ) 2 (CH 2 ) u- (EO / PO) v -OH, preference is given to α, ω-di (carbinol polyether) polysiloxanes having 3 <n ≦ 1000, 3 ≦ u ≦ 18, 1 <v ≦ 50.
Statt α,ω-OH-Gruppen kommen ebenfalls die entsprechenden difunktionellen Verbindungen mit Epoxy-, Isocyanato-, Vinyl-, AIIyI- und Di(meth)acryloylgruppen zum Einsatz, z. B. Polydimethylsiloxan mit Vinylendgruppen (850 - 1150 cST) oder TEGORAD 2500 der Fa. Tego Chemie Service.Instead of α, ω-OH groups are also the corresponding difunctional compounds with epoxy, isocyanato, vinyl, AIIyI- and di (meth) acryloyl used, for. B. Polydimethylsiloxan with vinyl end groups (850 - 1150 cST) or TEGORAD 2500 from. Tego Chemie Service.
Es kommen auch die Veresterungsprodukte von ethoxylierten/propoxylierten Trisiloxanen und höheren Siloxanen mit Acrylsäurecopolymeren und/oder Maleinsäurecopolymeren als modifizierende Verbindung infrage, z. B. BYK Silclean 3700 der Fa. Byk Chemie oder TEGO® Protect 5001 der Fa. Tego Chemie Service GmbH.There are also the esterification of ethoxylated / propoxylated trisiloxanes and higher siloxanes with acrylic acid copolymers and / or maleic acid copolymers as a modifying compound in question, z. B. BYK Silclean 3700 from Byk Chemie or TEGO® Protect 5001 from Tego Chemie Service GmbH.
Statt α,ω-OH-Gruppen kommen ebenfalls die entsprechenden difunktionellen Verbindungen mit -NHR"" mit R"" = H oder Alkyl zum Einsatz, z. B. die allgemein bekannten Aminosiliconöle der Firmen Wacker, Dow Corning, Bayer, Rhodia etc. zum Einsatz, die statistisch auf der Polysiloxankette verteilte (Cyclo)- Alkylaminogruppen oder (Cyclo)-Alkyliminogruppen auf ihrer Polymerkette tragen.Instead of α, ω-OH groups are also the corresponding difunctional compounds with -NHR "" with R "" = H or alkyl used, for. For example, the well-known aminosilicone oils from Wacker, Dow Corning, Bayer, Rhodia, etc., which carry randomly distributed (cyclo) -alkylamino groups or (cyclo) -alkylimino groups on their polymer chain on the polysiloxane chain.
c) Organosilane des Typs (RO)3Si(CnH2n+! ) und (RO)3Si(CnH2n+I), wobeic) organosilanes of the type (RO) 3 Si (C n H 2n +!) and (RO) 3 Si (C n H 2n + I), where
R ein Alkyl, wie z. B. Methyl, Ethyl-, n-Propyl-, i-Propyl, Butyl- n 1 bis 20.R is an alkyl, such as. For example, methyl, ethyl, n-propyl, i-propyl, butyl n 1 to 20.
Organosilane des Typs R'x(RO)ySi(CnH2n+1 ) und (RO)3Si(CnH2n+1 ), wobeiOrganosilanes of the type R'x (RO) ySi (CnH2n + 1) and (RO) 3Si (CnH2n + 1), wherein
R ein Alkyl, wie z. B. Methyl-, Ethyl-, n-Propyl-, i-Propyl-, Butyl-,R is an alkyl, such as. Methyl, ethyl, n-propyl, i-propyl, butyl,
R1 ein Alkyl, wie z. B. Methyl-, Ethyl-, n-Propyl-, i-Propyl-, Butyl-,R 1 is an alkyl, such as. Methyl, ethyl, n-propyl, i-propyl, butyl,
R' ein Cycloalkyl n eine ganze Zahl von 1 - 20 x+y 3 x 1 oder 2 y 1 oder 2 1 OR 'is a cycloalkyl n is an integer from 1 - 20 x + y 3 x 1 or 2 y 1 or 2 1 O
Organosilane des Typs (RO)3Si(CH2)m-R\ wobei R ein Alkyl, wie z. B. Methyl-, Ethyl-, Propyl-, m eine Zahl zwischen 0,1 - 20Organosilanes of the type (RO) 3 Si (CH 2) m R where R is an alkyl, such as. As methyl, ethyl, propyl, m is a number between 0.1 - 20
R1 Methyl-, Phenyl, -C4F9; OCF2-CHF-CF3, -C6F13, -0-CF2-CHF2, -NH2, -N3, -SCN, -CH=CH2, -NH-CH2-CH2-NH2, -N-(CH2-CH2-NH2J2,R 1 is methyl, phenyl, -C 4 F 9 ; OCF 2 -CHF-CF 3 , -C 6 F 13 , -O-CF 2 -CHF 2 , -NH 2 , -N 3 , -SCN, -CH = CH 2 , -NH-CH 2 -CH 2 -NH 2 , -N- (CH 2 -CH 2 -NH 2 J 2 ,
-0OC(CH3)C = CH2, -OCH2-CH(O)CH2, -NH-CO-N-CO-(CH2)5,-OOC (CH 3 ) C = CH 2 , -OCH 2 -CH (O) CH 2 , -NH-CO-N-CO- (CH 2 ) 5 ,
-NH-COO-CH3, -NH-COO-CH2-CH3,-NH-COO-CH 3 , -NH-COO-CH 2 -CH 3 ,
-NH-(CH2J3Si(OR)3, -Sx-(CH2)3)Si(OR)3, -SH-NR1R11R"1 (R1 = Alkyl, Phenyl; R" = Alkyl, Phenyl; R"1 = H, Alkyl, Phenyl, Benzyl, C2H4NR1111R'"" mit R"" = A, Alkyl und R""1 = H, Alkyl) bedeutet.-NH- (CH 2 J 3 Si (OR) 3 , -S x - (CH 2 ) 3 ) Si (OR) 3 , -SH-NR 1 R 11 R " 1 (R 1 = alkyl, phenyl; R" R 1 = H, alkyl, phenyl, benzyl, C 2 H 4 NR 1111 R '"" with R "" = A, alkyl and R "" 1 = H, alkyl).
Bevorzugte Silane sind die im Folgenden aufgeführten Silane: Triethoxysilan, Octadecyltimethoxisilan, 3-(Trimethoxysilyl)-propylmethacrylate, 3-(Trimethoxysilyl)-propylacrylate, 3-(Trimethoxysilyl)-methylmethacrylate, 3-(Trimethoxysilyl)-methylacrylate, 3-(Trimethoxysilyl)-ethylmethacrylate, 3-(Trimethoxysilyl)-ethylacrylate, 3-(Trimethoxysilyl)-pentylmethacrylate, 3-(Trimethoxysilyl)-pentylacrylate, 3-(Trimethoxysilyl)-hexylmethacrylate, 3-(Trimethoxysilyl)-hexylacrylate, 3-(Trimethoxysilyl)-butylmethacrylate, 3-(Trimethoxysilyl)-butylacrylate, 3-(Trimethoxysilyl)-heptylmethacrylate, 3-(Trimethoxysilyl)-heptylacrylate, 3-(Trimethoxysilyl)-octylmethacrylate, S-fTrimethoxysilyO-octylacrylate, Methyltrimethoxysilane, Methyltriethoxysilane, Propyltrimethoxisilane, Propyltriethoxisilane, Isobutyltrimethoxisilane, Isobutyltriethoxysilane, Octyltrimethoxysilane, Octyltriethoxysilane, Hexadecyltrimethoxysilane, Phenyltrimethoxysilane, Phenyltriethoxysilane,Preferred silanes are the silanes listed below: triethoxysilane, octadecyltimethoxysilane, 3- (trimethoxysilyl) -propylmethacrylate, 3- (trimethoxysilyl) -propylacrylate, 3- (trimethoxysilyl) -methylmethacrylate, 3- (trimethoxysilyl) -methylacrylate, 3- (trimethoxysilyl) ethylmethacrylate, 3- (trimethoxysilyl) -ethylacrylate, 3- (trimethoxysilyl) -pentylmethacrylate, 3- (trimethoxysilyl) -pentylacrylate, 3- (trimethoxysilyl) -hexylmethacrylate, 3- (trimethoxysilyl) -hexylacrylate, 3- (trimethoxysilyl) -butylmethacrylate , 3- (trimethoxysilyl) butyl acrylates, 3- (trimethoxysilyl) heptyl methacrylates, 3- (trimethoxysilyl) heptyl acrylates, 3- (trimethoxysilyl) octyl methacrylates, S-trimethoxysily O-octyl acrylates, methyltrimethoxysilanes, methyltriethoxysilanes, propyltrimethoxysilanes, propyltriethoxysilanes, isobutyltrimethoxysilanes, isobutyltriethoxysilanes , Octyltrimethoxysilanes, octyltriethoxysilanes, hexadecyltrimethoxysilanes, phenyltrimethoxysilanes, phenyltriethoxysilanes,
Tridecafluoro-1 ,1 ,2,2-tetrahydrooctyltriethoxysilane,Tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane,
Tetramethoxysilane, Tetraethoxysilane, Oligomeric tetraethoxysilane (DYNASIL® 40 Fa. Degussa), Tetra-n-propoxysilane, 3-Glycidyloxypropyltrimethoxysilane, 3-Glycidyloxypropyltriethoxysilane, 3-Methacryloxylpropyltrimethoxysilane, Vinyltrimethoxysilane, Vinyltriethoxysilane, 3-Mercaptopropyltrimethoxysilane,Tetramethoxysilanes, tetraethoxysilanes, oligomeric tetraethoxysilanes (DYNASIL® 40 from Degussa), tetra-n-propoxysilanes, 3-glycidyloxypropyltrimethoxysilanes, 3-glycidyloxypropyltriethoxysilanes, 3-methacryloxypropyltrimethoxysilanes, vinyltrimethoxysilanes, vinyltriethoxysilanes, 3-mercaptopropyltrimethoxysilanes,
3-Aminopropyltriethoxysilane, 3-Aminopropyltrimethoxysilane, 2-Aminoethyl-3- aminopropyltrimethoxysilane, Triaminofunctional propyltrimethoxysilane (DYN AS YLAN® TRIAMINO Fa. Degussa), N-(n-Butyl-3- aminopropyltrimethoxysilane, 3-Aminopropylmethyldiethoxysilane.3-aminopropyltriethoxysilanes, 3-aminopropyltrimethoxysilanes, 2-aminoethyl-3-aminopropyltrimethoxysilanes, triaminofunctional propyltrimethoxysilanes (DYN AS YLAN® TRIAMINO from Degussa), N- (n-butyl-3-aminopropyltrimethoxysilanes, 3-aminopropylmethyldiethoxysilanes.
Die Beschichtungsmittel, hier insbesondere die Silane oder Siloxane werden vorzugsweise in molaren Verhältnissen Mischoxid-Nanopartikel zu Silan von 1 :1 bis 10:1 zugegeben. Die Menge an Lösungsmittel beim Desagglomerieren beträgt im Allgemeinen 80 bis 90 Gew.-%, bezogen auf die Gesamtmenge an Mischoxid- Nanopartikel und Lösungsmittel.The coating compositions, in particular the silanes or siloxanes, are preferably added in molar ratios of mixed oxide nanoparticles to silane of from 1: 1 to 10: 1. The amount of solvent in the deagglomeration is generally 80 to 90 wt .-%, based on the total amount of mixed oxide nanoparticles and solvent.
Die Desagglomerierung durch Mahlen und gleichzeitige Modifizierung mit dem Beschichtungsmittel erfolgt vorzugsweise bei Temperaturen von 20 bis 1500C, besonders bevorzugt bei 20 bis 9O0C.The deagglomeration by grinding and simultaneous modification with the coating agent is preferably carried out at temperatures of 20 to 150 0 C, more preferably at 20 to 9O 0 C.
Erfolgt die Desagglomeration durch Mahlen, wird die Suspension anschließend von den Mahlperlen abgetrennt.If deagglomeration is carried out by grinding, the suspension is subsequently separated from the grinding beads.
Nach der Desagglomeration kann die Suspension zur Vervollständigung der Reaktion noch bis zu 30 Stunden erhitzt werden. Abschließend wird das Lösungsmittel abdestilliert und der verbleibende Rückstand getrocknet. Es kann auch vorteilhaft sein, die modifizierten Mischoxid-Nanopartikel im Lösungsmittel zu belassen und die Dispersion für weitere Anwendungen zu verwenden.After deagglomeration, the suspension can be heated to complete the reaction for up to 30 hours. Finally, the solvent is distilled off and the remaining residue is dried. It may also be advantageous to leave the modified mixed oxide nanoparticles in the solvent and to use the dispersion for other applications.
Es ist auch möglich, die Mischoxid- Nanopartikel in den entsprechenden Lösungsmitteln zu suspendieren und die Reaktion mit dem Beschichtungsmittel nach der Desagglomeration in einem weiteren Schritt durchzuführen.It is also possible to suspend the mixed oxide nanoparticles in the corresponding solvents and to carry out the reaction with the coating agent after deagglomeration in a further step.
Die so hergestellten, mit Beschichtungsmittel modifizierten Mischoxid-Nanopartikel können in transparente Oberflächenlackierungen oder -beschichtungen eingearbeitet werden, wodurch man einen verbesserten Kratzschutz erreicht. Durch die Modifizierung mit den Beschichtungsmitteln können die Mischoxid- Nanopartikel in nichtwässrigen Systemen problemlos dispergiert werden. Außerdem zeigen die Beschichtungen eine geringere Eintrübung im Vergleich zu Schichten, die unmodifzierte Nanopartikel enthalten. Beispiele:The coating oxide-modified mixed oxide nanoparticles prepared in this way can be incorporated into transparent surface finishes or coatings, thereby achieving improved scratch protection. Modification with the coating agents allows the mixed oxide nanoparticles to be readily dispersed in non-aqueous systems. In addition, the coatings show less clouding compared to layers containing unmodified nanoparticles. Examples:
Beispiel 1 :Example 1 :
Eine 50 %ig wässrige Lösung von Aluminiumchlorohydrat wurde mitA 50% aqueous solution of aluminum chlorohydrate was added
Magnesiumchlorid versetzt, dass nach der Kalzinierung das Verhältnis von Aluminiumoxid zu Magnesiumoxid 99,5 : 0,5 % betrug. Außerdem wurden der Lösung 2 % Kristallisationskeime einer Suspension aus Feinstkorund zugesetzt. Nachdem die Lösung durch Rühren homogenisiert wurde, erfolgte die Trocknung in einem Rotationsverdampfer. Das feste Aluminiumchlorohydrat-Magnesium chloride added that after calcination, the ratio of alumina to magnesium oxide was 99.5: 0.5%. In addition, 2% of nuclei were added to the solution to a suspension of fines. After the solution was homogenized by stirring, the drying was carried out in a rotary evaporator. The solid aluminum chlorohydrate
Magnesiumchlorid-Gemisch wurde in einer Reibschale zerkleinert, wobei ein grobes Pulver entstand.Magnesium chloride mixture was crushed in a mortar, resulting in a coarse powder.
Das Pulver wurde in einem Drehrohrofen bei 10500C kalziniert. Die Kontaktzeit in der heißen Zone betrug maximal 5 min. Es wurde ein weißes Pulver erhalten, dessen Kornverteilung dem Aufgabegut entsprach.The powder was calcined in a rotary kiln at 1050 0 C. The contact time in the hot zone was a maximum of 5 min. A white powder was obtained whose grain distribution corresponded to the feed material.
Eine Röntgenstrukturanalyse zeigt, dass überwiegend α-Aluminiumoxid vorliegt.An X-ray structure analysis shows that predominantly α-alumina is present.
Die Bilder der durchgeführten REM-Aufnahme (Rasterelektronenmikroskop) zeigten Kristallite im Bereich 10 - 80 nm (Abschätzung aus REM-Aufnahme), die als Agglomerate vorliegen. Der Restchlorgehalt betrug nur wenige ppm.The images of the SEM image taken (scanning electron microscope) showed crystallites in the range 10 - 80 nm (estimate from SEM image), which are present as agglomerates. The residual chlorine content was only a few ppm.
In einem weiteren Schritt wurden 40 g dieses mit Magnesiumoxid dotierten Korundpulvers in 160 g Isopropanol suspendiert. Der Suspension wurden 40 gIn a further step, 40 g of this magnesium oxide-doped corundum powder were suspended in 160 g of isopropanol. The suspension was 40 g
Trimethoxy-octylsilan zugegeben und einer vertikalen Rührwerkskugelmühle derTrimethoxy-octylsilane added and a vertical stirred ball mill of
Fa. Netzsch (Typ PE 075) zugeführt. Die eingesetzten Mahlperlen bestanden ausNetzsch (type PE 075) supplied. The grinding beads used consisted of
Zirkoniumoxid (stabilisiert mit Yttrium) und wiesen eine Größe von 0,3 mm auf.Zirconia (stabilized with yttrium) and had a size of 0.3 mm.
Nach drei Stunden wurde die Suspension von den Mahlperlen abgetrennt und unter Rückfluss für weitere 4 h gekocht. Anschließend wurde das Lösungsmittel abdestilliert und der zurückbleibende feuchte Rückstand im Trockenschrank beiAfter three hours, the suspension was separated from the milling beads and boiled under reflux for a further 4 h. The solvent was then distilled off and the residual moist residue in the drying oven at
1100C weitere 20 h getrocknet. Beispiel 2:110 0 C dried for a further 20 h. Example 2:
40 g des Oxidgemischs (mit MgO dotierter Korund) aus Beispiel 1 wurde in 160 g Methanol suspendiert und in einer vertikalen Rührwerkskugelmühle der Fa. Netzsch (Typ PE 075) desagglomeriert. Nach 3 h wurde die Suspension von den Perlen abgetrennt und in einen Rundkolben mit Rückflusskühler überführt. Der Suspension wurden 40 g Trimethoxy-octylsilan zugegeben und unter Rückfluss auf 2 h erhitzt. Nach Entfernung des Lösungsmittels wurde das beschichtete Oxidgemisch isoliert und im Trockenschrank für weitere 20 h bei 1100C getrocknet. Das so erhaltene Produkt ist identisch zur Probe aus Beispiel 1.40 g of the oxide mixture (MgO-doped corundum) from Example 1 was suspended in 160 g of methanol and deagglomerated in a vertical stirred ball mill from Netzsch (type PE 075). After 3 hours, the suspension was separated from the beads and transferred to a round bottom flask with reflux condenser. To the suspension was added 40 g of trimethoxy-octylsilane and heated at reflux for 2 h. After removal of the solvent, the coated oxide mixture was isolated and dried in a drying oven for another 20 h at 110 0 C. The product thus obtained is identical to the sample from Example 1.
Beispiel 3:Example 3:
40 g des Oxidgemischs (mit MgO dotierter Korund) aus Beispiel 1 wurde in 160 g Methanol suspendiert und in einer vertikalen Rührwerkskugelmühle der Fa. Netzsch (Typ PE 075) desagglomeriert. Nach 2 h wurden 20 g 3-(Trimethoxysilyl)-propyl-methacrylat (Dynasilan Memo; Degussa) zugegeben und die Suspension für weitere 2 h in der Rührwerkskugelmühle desagglomeriert. Anschließend wurde die Suspension von den Perlen abgetrennt und in einen Rundkolben mit Rückflusskühler überführt. Für weitere 2 h wurde unter Rückfluss erhitzt, bevor das Lösungsmittel abdestilliert wurde.40 g of the oxide mixture (MgO-doped corundum) from Example 1 was suspended in 160 g of methanol and deagglomerated in a vertical stirred ball mill from Netzsch (type PE 075). After 2 h, 20 g of 3- (trimethoxysilyl) propyl methacrylate (Dynasilan Memo, Degussa) were added and the suspension was deagglomerated in the stirred ball mill for a further 2 h. Subsequently, the suspension was separated from the beads and transferred to a round bottom flask with reflux condenser. Reflux was continued for an additional 2 hours before the solvent was distilled off.
Beispiel 4:Example 4:
40 g des Oxidgemischs (mit MgO dotierter Korund) aus Beispiel 1 wurde in 160 g Aceton suspendiert und in einer vertikalen Rührwerkskugelmühle der Fa. Netzsch (Typ PE 075) desagglomeriert. Nach 2 h wurden 20 g Aminopropyl-trimethoxysilan (Dynasilan Ammo; Degussa) zugegeben und die Suspension für weitere 2 h in der Rührwerkskugelmühle desagglomeriert. Anschließend wurde die Suspension von den Perlen abgetrennt und in einen Rundkolben mit Rückflusskühler überführt. Für weitere 2 h wurde unter Rückfluss erhitzt, bevor das Lösungsmittel abdestilliert wurde. Beispiel 5:40 g of the oxide mixture (doped with MgO corundum) from Example 1 was suspended in 160 g of acetone and disagglomerated in a vertical stirred ball mill from. Netzsch (type PE 075). After 2 h, 20 g of aminopropyltrimethoxysilane (Dynasilan Ammo, Degussa) were added and the suspension was deagglomerated in the stirred ball mill for a further 2 h. Subsequently, the suspension was separated from the beads and transferred to a round bottom flask with reflux condenser. Reflux was continued for an additional 2 hours before the solvent was distilled off. Example 5:
40 g des Oxidgemischs (mit MgO dotierter Korund) aus Beispiel 1 wurde in 160 g Aceton suspendiert und in einer vertikalen Rührwerkskugelmühle der Fa. Netzsch (Typ PE 075) desagglomeriert. Nach 2 h wurden 20 g Glycidyl-trimethoxysilan (Dynasilan Glymo; Degussa) zugegeben und die Suspension für weitere 2 h in er Rückwerkskugelmühle desagglomeriert. Anschließend wurde die Suspension von den Perlen abgetrennt und in einen Rundkolben mit Rückflusskühler überführt. Für weitere 2 h wurde unter Rückfluss erhitzt, bevor das Lösungsmittel abdestilliert wurde.40 g of the oxide mixture (doped with MgO corundum) from Example 1 was suspended in 160 g of acetone and disagglomerated in a vertical stirred ball mill from. Netzsch (type PE 075). After 2 h, 20 g of glycidyltrimethoxysilane (Dynasilan Glymo, Degussa) were added and the suspension was deagglomerated for a further 2 hours in the recycle ball mill. Subsequently, the suspension was separated from the beads and transferred to a round bottom flask with reflux condenser. Reflux was continued for an additional 2 hours before the solvent was distilled off.
Beispiel 6:Example 6:
40 g des Oxidgemischs (mit MgO dotierter Korund) aus Beispiel 1 wurde in 160 g n-Butanol suspendiert und in einer vertikalen Rührwerkskugelmühle der Fa. Netzsch (Typ PE 075) desagglomeriert. Nach 2 h wurde ein Gemisch aus 5 g Aminopropyl-trimethoxysilan (Dynasilan Glymo; Degussa) und 15 g Octyltriethoxysilan zugegeben und die Suspension für weitere 2 h in der Rührwerkskugelmühle desagglomeriert. Die Suspension bleibt über Wochen stabil ohne Anzeichen einer Sedimentation des beschichteten Mischoxids. 40 g of the oxide mixture (MgO doped corundum) from Example 1 was suspended in 160 g of n-butanol and disagglomerated in a vertical stirred ball mill from Netzsch (type PE 075). After 2 h, a mixture of 5 g of aminopropyltrimethoxysilane (Dynasilan Glymo; Degussa) and 15 g of octyltriethoxysilane was added and the suspension was deagglomerated in the stirred ball mill for a further 2 h. The suspension remains stable for weeks without evidence of sedimentation of the coated mixed oxide.

Claims

Patentansprüche claims
1. Oberflächenmodifizierte Nanopartikel bestehend aus 50 - 99,9 Gew.-% Aluminiumoxid und 0,1 - 50 Gew.-% von Elementen der I. oder II. Hauptgruppe des Periodensystems, wobei diese Nanopartikel mit einem Beschichtungsmittel an der Oberfläche modifiziert sind.1. Surface-modified nanoparticles consisting of 50-99.9% by weight of aluminum oxide and 0.1-50% by weight of elements of the 1st or 2nd main group of the Periodic Table, these nanoparticles being modified with a coating agent on the surface.
2. Oberflächenmodifizierte Nanopartikel nach Anspruch 1 , dadurch gekennzeichnet, dass das Kristallgitter des Aluminiumoxids überwiegend in der rhomboedrischen α-Modifikation vorliegt.2. Surface-modified nanoparticles according to claim 1, characterized in that the crystal lattice of the aluminum oxide is present predominantly in the rhombohedral α-modification.
3. Oberflächenmodifizierte Nanopartikel nach den Ansprüchen 1 oder 2, dadurch gekennzeichnet, dass als Beschichtungsmittel Siloxane oder Silane verwendet werden.3. Surface-modified nanoparticles according to claims 1 or 2, characterized in that siloxanes or silanes are used as coating agents.
4. Oberflächenmodifizierte Nanopartikel nach den Ansprüchen 1 - 3, dadurch gekennzeichnet, dass die Mischoxide eine Kristallitgröße kleiner 1 μm, bevorzugt kleiner 0,2 μm, besonders bevorzugt zwischen 0,001 und 0,1 μm aufweisen.4. Surface-modified nanoparticles according to claims 1-3, characterized in that the mixed oxides have a crystallite size of less than 1 μm, preferably less than 0.2 μm, more preferably between 0.001 and 0.1 μm.
5. Verfahren zur Herstellung der oberflächenmodifizierten Nanopartikel gemäß Anspruch 1 , dadurch gekennzeichnet, dass man Agglomerate dieser Nanopartikel in Gegenwart eines organischen Lösungsmittels desagglomeriert und gleichzeitig oder anschließend mit einem Beschichtungsmittel, bevorzugt mit einem Silan oder Siloxan oder deren Mischungen behandelt.5. A process for preparing the surface-modified nanoparticles according to claim 1, characterized in that agglomerates of these nanoparticles are deagglomerated in the presence of an organic solvent and treated simultaneously or subsequently with a coating agent, preferably with a silane or siloxane or mixtures thereof.
6. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass man die Agglomerate durch Mahlen desagglomeriert.6. The method according to claim 5, characterized in that the agglomerates are deagglomerated by grinding.
7. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass man die Agglomerate durch Ultraschall zerstört.7. The method according to claim 5, characterized in that destroying the agglomerates by ultrasound.
8. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass man die Agglomerate durch Mahlen in Rührwerkskugelmühlen desagglomeriert. 8. The method according to claim 5, characterized in that the agglomerates are disagglomerated by grinding in stirred ball mills.
9. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass man die Agglomerate durch Mahlen oder durch Einwirken von Ultraschall bei 20 bis 900C desagglomeriert.9. The method according to claim 5, characterized in that the agglomerates are deagglomerated by milling or by the action of ultrasound at 20 to 90 0 C.
10. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass man die Desagglomeration in einem CrC4-Alkohol als Lösungsmittel vornimmt.10. The method according to claim 5, characterized in that one carries out the deagglomeration in a CrC 4 alcohol as a solvent.
11. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass man die Desagglomeration in Aceton, Tetrahydrofuran, Butylacetat und sonstigen in der Lackindustrie eingesetzten Lösungsmitteln durchführt.11. The method according to claim 5, characterized in that one carries out the deagglomeration in acetone, tetrahydrofuran, butyl acetate and other solvents used in the paint industry.
12. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass das molare Verhältnis von Nanopartikel zu Beschichtungsmittel 1 :1 bis 10:1 beträgt. 12. The method according to claim 5, characterized in that the molar ratio of nanoparticles to coating agent 1: 1 to 10: 1.
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Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007009658A1 (en) * 2005-07-16 2007-01-25 Clariant Finance (Bvi) Limited Nanoparticles of alumina and oxides of elements of main groups i and ii of the periodic table, and their preparation
DE102005033393B4 (en) * 2005-07-16 2014-04-03 Clariant International Limited Process for the preparation of nanocrystalline α-Al 2 O 3
WO2007020063A2 (en) * 2005-08-18 2007-02-22 Clariant International Ltd Coating materials containing mixed oxide nanoparticles consisting of 50-99.9 % by weight al203 and 0.1-50 % by weight oxides of elements of main groups i or ii of the periodic table
DE102006032582A1 (en) * 2006-07-13 2008-01-24 Clariant International Limited Process for the production of nanoparticles from aluminum spinels and their use
DE102007008468A1 (en) * 2007-02-19 2008-08-21 Clariant International Ltd. Laminates containing metal oxide nanoparticles
KR100947891B1 (en) 2007-11-15 2010-03-17 한국과학기술연구원 Surface modifiers and process for surface modifications of particles of metal oxide using the same
US8323360B2 (en) 2008-06-30 2012-12-04 3M Innovative Properties Company Method of crystallization
KR102126126B1 (en) * 2018-09-28 2020-06-23 한국자동차연구원 Method for nano coating an inorganic filler and thermal dissipation composite material and sheet using the inorganic filler prepared therefrom
KR102605719B1 (en) * 2020-12-23 2023-11-22 중앙대학교 산학협력단 Surface modification method of inorganic particles using ball milling process and surface modificated inorganic particles modificated by the method

Family Cites Families (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5037806A (en) * 1973-06-27 1975-04-08
AT389884B (en) * 1986-10-03 1990-02-12 Treibacher Chemische Werke Ag METHOD FOR PRODUCING A Sintered Abrasive Material Based On Alpha-Al2o3
JPH06104816B2 (en) * 1990-02-09 1994-12-21 日本研磨材工業株式会社 Sintered alumina abrasive grains and method for producing the same
CN1068092A (en) * 1991-06-21 1993-01-20 瑞士隆萨股份公司 Production is the agglomerated material method of abrasive material particularly of matrix with the Alpha-alumina
DE4202694C1 (en) * 1992-01-31 1993-07-01 Degussa Ag, 6000 Frankfurt, De Silane surface-modified pyrogenic alumina, for use in toner - to increase charge stability, produced by spraying with silane mixt. free from solvent
JPH06321534A (en) * 1993-05-18 1994-11-22 Taimei Kagaku Kogyo Kk Production of crystallite alumina abrasive powder
CN1105698C (en) * 1993-11-12 2003-04-16 美国3M公司 Abrasive grain and method for making the same
JPH08267363A (en) * 1995-03-30 1996-10-15 Fuji Photo Film Co Ltd Abrasive body
US20030077221A1 (en) * 2001-10-01 2003-04-24 Shivkumar Chiruvolu Aluminum oxide powders
DE19846660A1 (en) * 1998-10-09 2000-04-13 Inst Oberflaechenmodifizierung Polymerizable metal oxide particles, e.g. useful in coating compositions, adhesives or sealants, comprise a metal oxide core functionalized with reactive groups
DE19922492A1 (en) * 1999-05-14 2000-11-16 Fraunhofer Ges Forschung Production of a nano-corundum used in the production of aluminum oxide sintered products uses chlorine-free inorganic precursors as starting material in a liquid medium to form a sol which is subsequently hydrolyzed
US6896958B1 (en) * 2000-11-29 2005-05-24 Nanophase Technologies Corporation Substantially transparent, abrasion-resistant films containing surface-treated nanocrystalline particles
DE10063092A1 (en) * 2000-12-18 2002-06-20 Henkel Kgaa Nanoscale materials in hygiene products
FR2831156B1 (en) * 2001-10-18 2004-02-20 Pechiney Aluminium BRUSHED CALCINE ALUMINA INTENDED TO ENTER IN THE COMPOSITION OF A PRECURSOR FOR REFRACTORY MATERIAL, AND PROCESS FOR OBTAINING SAID ALUMINA
US20030148042A1 (en) * 2001-12-28 2003-08-07 Zhikai Wang Ultrasonic method for the production of inorganic/organic hybrid nanocomposite
JP4132863B2 (en) * 2002-02-18 2008-08-13 株式会社ノリタケカンパニーリミテド Oxygen ion conductor molding raw material powder and method for producing the same
WO2003080743A2 (en) * 2002-03-19 2003-10-02 The Regents Of The University Of California Stabilized inorganic particles
TWI227719B (en) * 2002-11-22 2005-02-11 Far Eastern Textile Ltd Method of preparing a surface modifier for nanoparticles dispersion of inorganic oxide nanoparticles
DE10304849A1 (en) * 2003-02-06 2004-08-19 Institut für Neue Materialien gemeinnützige Gesellschaft mit beschränkter Haftung Chemomechanical production of functional colloids
JP4197141B2 (en) * 2003-08-22 2008-12-17 電気化学工業株式会社 Spherical alumina powder and use thereof
DE102005006870A1 (en) * 2005-02-14 2006-08-24 Byk-Chemie Gmbh Surface-modified nanoparticles, process for their preparation and their use
DE102005033393B4 (en) * 2005-07-16 2014-04-03 Clariant International Limited Process for the preparation of nanocrystalline α-Al 2 O 3
WO2007009658A1 (en) * 2005-07-16 2007-01-25 Clariant Finance (Bvi) Limited Nanoparticles of alumina and oxides of elements of main groups i and ii of the periodic table, and their preparation
DE102005039435A1 (en) * 2005-08-18 2007-03-01 Clariant International Limited Process for the preparation of silane-surface-modified nanocorundum
DE102005039436B4 (en) * 2005-08-18 2009-05-07 Clariant International Limited Coating compositions containing silane-modified nanoparticles
WO2007020063A2 (en) * 2005-08-18 2007-02-22 Clariant International Ltd Coating materials containing mixed oxide nanoparticles consisting of 50-99.9 % by weight al203 and 0.1-50 % by weight oxides of elements of main groups i or ii of the periodic table
US20090130217A1 (en) * 2006-03-17 2009-05-21 Clariant International Ltd. Cosmetic Composition Containing Nanoparticulate a-Alumina

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
None *
See also references of WO2007020064A1 *

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KR20080036156A (en) 2008-04-24
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US20090226726A1 (en) 2009-09-10
WO2007020064A1 (en) 2007-02-22

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