Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K9/00—Use of pretreated ingredients
  • C08K9/08—Ingredients agglomerated by treatment with a binding agent
• • 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
  • 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
  • C09C1/28—Compounds of silicon
  • C09C1/30—Silicic acid
  • C09C1/3072—Treatment with macro-molecular organic compounds
• • 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
  • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
  • C09C3/10—Treatment with macromolecular organic compounds
• • 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

Definitions

• the present invention relates to surface-modified particles that are dispersible in organic solvents and their use for incorporation into polymers, paints and coatings.
• Inorganic particles in particular nanoparticles, are usually prepared in aqueous dispersion and often have to be converted into organic media. If, for example, the hydrophilic nanoparticles are brought too quickly into a non-polar environment, it occurs
• the object of the present invention is to provide processes for the production of surface-modified particles in which particles,
• the object of the present invention is achieved by surface-modified inorganic particles having attached to the surface of the particle random copolymers of at least one monomer having hydrophobic radicals and at least one monomer having hydrophilic radicals, characterized in that they are obtainable by a method in which Step a) in a solvent mixture containing water, at least one water-immiscible organic solvent and at least one other acting as a solubilizer, organic solvent, inorganic particles and random copolymers of at least one monomer having hydrophobic radicals and at least one monomer having hydrophilic radicals with each other, under covalent or non-covalent (physical) attachment of the random copolymer of at least one monomer having hydrophobic radicals and at least one monomer having hydrophilic radicals to the surface of the inorganic Particles are reacted, and in a step b) water and / or methanol is added to form a biphasic system and the phases are separated, wherein the surface-modified inorganic particles are dis
• the resulting surface-modified particles have the advantage that they are either dispersed in a non-polar solvent, or after optional separation again in nonpolar solvents or application systems, such as paints or varnishes can be redispersed.
• the particles thus obtained are particularly advantageous in terms of incorporation into hydrophobic polymers, solvents or paints, since the particles can be distributed homogeneously in the polymer, solvent or paint by simple measures. This allows improved properties such as increased transparency or better mechanical stability compared to systems with inhomogeneous distribution.
• Essential for the properties of the particles according to the invention is the process for their preparation, which is also the subject of the present invention. Only by this method, the surface-modified particles of the invention are accessible, which have the redispersibility in nonpolar solvents as a special property. For this reason, a process for the preparation of surface-modified particles with random copolymers bound to the surface of the particles of at least one monomer having hydrophobic radicals and at least one monomer having hydrophilic radicals, characterized in that in a step a) in a solvent mixture containing water, at least one water-immiscible, organic solvent and at least one further acting as a solubilizer, organic solvent, inorganic particles and random copolymers of at least one monomer having hydrophobic radicals and at least one monomer having hydrophilic radicals are reacted together, and in a step b) Water is added to form a biphasic system and the phases are separated, wherein the surface-modified inorganic particles are dispersed in the non-polar solvent
• the inorganic particles to be modified and the random copolymers to be used are reacted with one another in a ternary solvent system.
• the solvent system comprises at least one nonpolar solvent, water and at least a third, acting as a solubilizer between the non-polar solvent and water, organic solvent, so that the mixture is a single-phase system.
• Suitable non-polar solvents are hydrocarbons and halogenated hydrocarbons and / or mixtures thereof.
• the nonpolar solvents are preferably alkanes and cyclic alkanes, in particular hexane, heptane, octane, nonane and / or cyclohexane.
• organic solvents are polar protic and aprotic solvents, preferably alcohols and ethers, more preferably ethanol, methanol and isopropanol.
• the solvent system is monophasic, that is, there is only one phase in total.
• the amount of organic solvent acting as a solubilizer is chosen so that a phase separation is achieved by further addition of water.
• the amount depends on the nonpolar solvent or solvent mixture used and its quantitative ratio to water. In general, it is subject to the expertise of the skilled person, depending on the nature of
• Solvent suitable mixing ratios that lead to the formation of a monophasic solvent system, for example, from G. Wypych: Handbook of solvents, ChemTec Publishing 2001, R. Koningsveld, WH Stockmayer, N. Nies: Polymer phase diagrams, Oxford Univ. Press 2001 or PW Atkins, Julio de Paula, Atkin ' s physical chemistry, Oxford Univ. Press 2002.
• the inorganic particles and the random copolymers to be used are reacted with each other.
• the random copolymers to be used can first be dissolved in the nonpolar solvent or solvent mixture and then mixed with the inorganic particles dispersed in the polar solvents.
• amphiphilic copolymers do not form an emulsion under the stated solvent conditions, which is due to dynamic
• Non-covalent attachment in the sense of the present invention means that the attachment is based essentially on physical interactions between copolymer and surface of the particles.
• the copolymers are covalently bonded to the surface of the particles, since this ensures a particularly strong binding of the copolymers to the surface of the particles.
• water is added to the abovementioned reaction mixture to form a biphasic system.
• the addition of water increases the amount of polar solvent to such an extent that segregation of the ternary solvent system occurs with formation a biphasic system of polar and nonpolar solvent (s).
• polar and nonpolar solvent s
• the surface modification of the particles with the statistical copolymers to be used they are dispersed in the nonpolar solvent or solvent mixture.
• the previously hydrophilic inorganic particles were modified to such an extent that they are dispersed in nonpolar solvents or, if appropriate after separation from the nonpolar solvent and, if appropriate, drying, can be redispersed in organic, in particular nonpolar, solvents.
• the dried surface-modified particles obtained in this way are also the subject of the present invention.
• the reaction preferably takes place in the temperature range from 20 to 100 ° C. for 1 to 20 minutes.
• For accelerated phase separation is preferably cooled to 0 0 C after the addition of water.
• the particles can be dried and redispersed again in an organic, in particular non-polar solvent. Turbidity measurements after redispersion show the same values as before drying. This shows that the particles can be dried and redispersed without agglomeration.
• the measurement of turbidity is carried out in the context of the present invention by means of UV / VIS / NIR spectrometer Lambda 900 with integration sphere (150 mm). The dispersions are measured at a layer thickness of 0.5 cm in transmission. The directional and diffuse components are calculated. The lower the diffuse component of the transmittance, the less turbid and therefore more transparent the sample appears. The visual appearance of the samples is transparent (opalescent).
• the statistical copolymers to be used according to the invention preferably have a molar ratio of structural units having hydrophobic radicals to structural units having hydrophilic radicals in the random copolymer in the range 1: 10 to 500: 1, preferably in the range 1: 1 to 100: 1 and particularly preferably in the range 7: 3 to 10: 1.
• the determination of the weight average molecular weight M w is carried out by gel permeation chromatography GPC, as known from the literature, for example from Vollmert B., "Outline of Macromolecular Chemistry” Volume 3, E-Volmert Verlag, Düsseldorf, 1988 or Lechner, MD, Gerhke, K ., Nordmeier EH “Macromolecular Chemistry” Birkhäuser Verlag, Berlin,
• GPC measurements are carried out against a respectively selected Standard (PMMA, PS, PC, PI, etc) in a suitable solvent in a corresponding column at 3O 0 C. Detection takes place via an ERC RI-101 differential refractometer from Ercatech AG or a SOMA S-3702 UV detector from Soma, Japan.
• X and Y correspond to the radicals of conventional nonionic or ionic monomers
• R 1 is hydrogen or a hydrophobic side group, preferably selected from the branched or unbranched alkyl radicals at least 4 carbon atoms in which one or more, preferably all H atoms may be replaced by fluorine atoms
• R 2 is a hydrophilic side group, preferably an amino, ammonium, phosphonate, sulfonate, polyol or polyether Ran, ran means that the repeating unit in random order in the
• terpolymers can also be used.
• the formula I must then be supplemented accordingly, for example to formula Ia
• X, Y and Z correspond to the radicals of conventional nonionic or ionic monomers Q and
• R 1 is hydrogen or a hydrophobic side group, preferably selected from the branched or unbranched alkyl radicals having at least 4 carbon atoms in which one or more, preferably all H atoms may be replaced by fluorine atoms, and5 R 2 and R 3 are independently for a hydrophilic
• Side group which preferably has an amino, ammonium, phosphonate, sulfonate, polyol or polyether radical, ran means that the repeating unit occurs in a random sequence in the polymer, Q and wherein within a molecule -XR 1 , - YR 2 and -ZR 3 may each have several different meanings, meet the requirements of the invention in a special way.
• Particularly preferred according to the invention are those polymers in which R 2 is a polyethylene oxide chain.
• polymers according to formula I are particularly preferred in which Y is pyridyl and R 2 is preferably a hydrophilic side group, the one
• R 2 is particularly preferred
• R 2 is preferably a side group - (CH 2 ) m - (N + (CH 3 ) 2 ) - (CH 2 ) n -SO 3 - or one Side group - (CH 2) m - (N + (CH 3) 2 MCH 2 ) n-PO 3 2- , where m is an integer from the range of 1 to 30, preferably from the range 1 to 6, particularly preferably 2, and n is an integer from the range of 1 to 30, preferably from the range 1 to 8, particularly preferably 3, advantageously use.
• the copolymers are amphiphilic copolymers based on 2-ethylhexyl methacrylate and polyethylene glycol methacrylate.
• the ratio of ethylhexyl methacrylate to polyethylene glycol methacrylate is 99: 1 to 60:40, in particular 95: 5 to 70:30, more preferably 93: 7 to 85:15 (data in mol .-%).
• the copolymers mentioned can be prepared according to the following scheme:
• EHMA ethylhexyl methacrylate
• PEGMA polyethylene glycol methacrylate
• the copolymers are amphiphilic copolymers based on 2-ethylhexyl methacrylate (EHMA) and 4-vinylpyridine (4-VP), wherein preferably the pyridine units contained in the polymer produced are further functionalized by means of 1,3-propane sultone ,
• EHMA 2-ethylhexyl methacrylate
• 4-VP 4-vinylpyridine
• the ratio of ethylhexyl methacrylate to 4-vinylpyridine is 99: 1 to 60:40, in particular 98: 2 to 85:15 (in mol%).
• the copolymers mentioned can be prepared according to the following scheme:
• ethylhexyl methacrylate (EHMA) and 4-vinylpyridine (4-VP) are copolymerized by known processes, preferably free-radically in toluene, for example by addition of AIBN and optionally in the presence of a regulator (chain transfer agent), for example mercaptoethanol.
• a regulator chain transfer agent
• the pyridine units contained in the copolymer are reacted by means of 1, 3-propane sultone.
• These copolymers are preferably suitable for the functionalization of SiO 2 nanoparticles, cerium oxide and / or aluminum oxide nanoparticles, very particularly preferably for the functionalization of cerium oxide and / or aluminum oxide nanoparticles.
• the copolymers are preferably terpolymers consisting of the monomers 2- (ethylhexyl) methacrylate (EHMA), poly (ethylene glycol) methacrylate (PEOMA) and 2-
• DMAEMA (Dimethylaminoethyl) methacrylate
• the dialkylamino group introduced by DMAEMA into the copolymer is capable of undergoing hydrogen bonding, which becomes particularly important when incorporation of the nanoparticles of the invention into a polymer capable of forming hydrogen bonds, for example, polyurethanes.
• copolymers may contain styrene, vinylpyrrolidone, vinylpyridine, halogenated styrene or methoxystyrene, these examples being not limiting.
• styrene vinylpyrrolidone
• vinylpyridine vinylpyridine
• halogenated styrene methoxystyrene
• Invention polymers are used, which are characterized in that at least one structural unit is an oligo- or polymer, preferably a macromonomer, with polyethers, polyolefins and polyacrylates are particularly preferred as macromonomers.
• Suitable particles are selected from the group comprising hydrophilic and hydrophobic, in particular hydrophilic particles, in particular nanoparticles, based on oxides, hydroxides, phosphates, sulfides, sulfates, carbonates of silicon, titanium, zinc, aluminum, cerium, cobalt, chromium, nickel , Iron, yttrium and / or zirconium, or with oxides or hydroxides of silicon coated metals, such as Ag, Cu, Fe, Au, Pd, Pt or alloys.
• the particles based on oxides, hydroxides, sulfides, sulfates, carbonates of titanium, zinc, aluminum, cerium, cobalt, chromium, nickel, iron, yttrium and / or zirconium may optionally be coated with oxides or hydroxides of silicon.
• the individual oxides can also be present as mixtures.
• the particles preferably have an average particle size, determined by means of a Malvern ZETASIZER 3000 (dynamic light scattering) or transmission electron microscope, of from 3 to 200 nm, in particular from 20 to 80 nm and very particularly preferably from 30 to 50 nm.
• the distribution of particle sizes is narrow, ie Fluctuation width is less than 10O% of the mean value, particularly preferably at most 50% of the mean value (according to particle distribution function, determined by dynamic light scattering).
• the measurements are carried out at room temperature. Measured at a laser wavelength of 633 nm.
• the sample volume is in all cases 3 ml at a concentration of 5% by weight of particles in butyl acetate.
• the samples are measured unfiltered. 0
• the wavelength is 632.8 nm.
• the particle concentration in the sample is 0.2 g / L, whereby 5 samples are obtained by means of a 0.45 ⁇ m filter be filtered before the measurement.
• nanoparticles based on silicon dioxide Preference is given to using nanoparticles based on silicon dioxide, aluminum oxide (Al 2 O 3 ) and cerium oxide (CeO 2 ). Particular preference is given to using nanoparticles based on silicon dioxide
• nanohektorites for example, from the company
• silica sols (SiO 2 in water) prepared from ion-exchanged c water glass are also particularly preferred.
• surface modified inorganic particles either in the form of a dispersion or as dried particles according to the present invention for incorporation into polymers, paints and coatings, Q is also a subject of the present invention.
• the incorporation into polymers and lacquers can be carried out by customary methods for the preparation of polymer preparations.
• the polymer material can be mixed with nanoparticles according to the invention, preferably with the dried particles, preferably in an extruder or kneader, and by mixing the nanoparticles with the nanoparticles
• Polymer output components of 2K coating systems can be incorporated into 2K coating systems.
• 2K paint systems are 2-component paint systems.
• Preferred polymers are polycarbonate (PC), polyethylene terephthalate (PETP), polyimide (PI), polystyrene (PS), polymethyl methacrylate (PMMA), polyolefins, preferably polybutadiene and polyisoprene and copolymers containing at least a portion of one of the polymers mentioned, and 2K coating systems. for example, comprising polyurethanes.
• a particular advantage of the particles according to the invention consists in the fact that, for the homogeneous distribution of the particles in a polymer, only a low energy input compared to the prior art is required.
• the polymers may also be dispersions of polymers, such as, for example, paints.
• the incorporation can be done by conventional mixing processes.
• the dispersions of the particles according to the invention obtained in the process in the non-polar solvent can often be used directly. In this way, an additional isolation step can be omitted and the production of the paint or the color is facilitated, the production costs are lowered.
• polymer preparations according to the invention containing the nanoparticles are also particularly suitable for coating surfaces.
• Surfaces coated with polymers, lacquers and paints containing surface modified inorganic particles according to the present invention, are also the subject of the present invention.
• Cyclohexane HPLC grade
• n-hexane HPLC grade
• ethanol HPLC grade
• 2-ethylhexyl) methacrylate 99%
• 2,2'-azobis (2-methyl-propionitrile) AIBN
• mercaptoethanol purchased from Acros and (polyethylene glycol) methacrylate (M - 360 g / mol) from Sigma- Aldrich.
• (2-Ethylhexyl) methacrylate and 2- (dimethylaminoethyl) methacrylate are dried over CaH 2 and then distilled in vacuo.
• (Polyethylene glycol) methacrylate, AIBN and mercaptoethanol are used as received. Dynamic light scattering is measured on a Malvern Zetasizer 3000.
• the synthesis of the copolymers is carried out by free-radical copolymerization of 2- (ethylhexyl) methacrylate (EHMA) and (polyethylene oxide) methacrylate (PEOMA).
• EHMA 2- (ethylhexyl) methacrylate
• PEOMA polyethylene oxide methacrylate
• EHMA, PEOMA, mercaptoethanol and toluene are presented and degassed this solution and then heated to 70 0 C.
• the AIBN dissolved in 1/12 of the amount of toluene, was added and then stirred at this temperature for 24 h. All weights are listed in the table below. After cooling the solution to room temperature, the resulting
• the polydispersity (PDI) of the copolymers is determined by GPC (gel permeation chromatography). The measurement is made against PMMA (polymethyl methacrylate) as the standard at a temperature of 30 0 C using the following columns: MZ-Gel SDplus 10E6, 10E4 and 500 of the MZ Analysentechnik GmbH.
• the eluent used is tetrahydrofuran (THF).
• the detection of the polymer fraction is carried out by means of an ERC RI-101 differential refractometer from Ercatech AG. Surface modification by means of latent biphasic ternary solvent systems:
• Dynamic light scattering gives a mean hydrodynamic diameter of about 37 nm and a narrow, monomodal size distribution. This is confirmed by SEM (scanning electron microscopy) images, whereby this results in a mean particle diameter of about 25 nm. The images are taken with the Zeiss Gemini 912 Zeiss machine.
• the functionalized particles are stable in solution, and do not change their diameter with increasing lifetime. Furthermore, the particles according to the invention are redispersible in the solvent used for the synthesis, since the hydrodynamic radius after redispersion does not differ significantly from that before the redispersion.
• the synthesis of the terpolymers is carried out by free-radical copolymerization of 2- (ethylhexyl) methacrylate (EHMA), poly (ethylene glycol) methacrylate (PEOMA) and 2- (dimethylaminoethyl) methacrylate (DMAEMA).
• EHMA 2- (ethylhexyl) methacrylate
• PEOMA poly (ethylene glycol) methacrylate
• DMAEMA 2- (dimethylaminoethyl) methacrylate
• the terpolymers obtained show molecular weights of 10,600 g / mol in the case of the terpolymer I and 10300 g / mol in the case of the terpolymer II.
• 300 mg of the terpolymer are mixed with 240 mg of a SiO 2 particle dispersion
• Particle I 300 mg terpolymer I and 240 mg of a 30% by weight SiO 2 particle dispersion in H 2 O.
• Particle II 300 mg terpolymer II and 240 mg of a 30% by weight SiO 2 particle dispersion in H 2 O.
• Example A 500 mg DP 680 BA 140 mg DD N 3390 BA / SN
• Example B 500 mg DP 680 BA 170 mg DD N 3390 BA / SN
• the copolymer is synthesized by radical copolymerization of 2- (ethylhexyl) methacrylate (EHMA) and 4-vinylpyridine (4-VP).
• EHMA 2- (ethylhexyl) methacrylate
• 4-VP 4-vinylpyridine
• the EHMA, the 4-VP, mercaptoethanol and toluene are presented and degassed this solution and then heated to 70 0 C.
• the AIBN dissolved in 1/12 of the amount of toluene, was added and then stirred at this temperature for 24 h. All weights are listed in the table below.
• the resulting copolymer is precipitated in methanol, the decanted supernatant solution and the residue dried under reduced pressure at 60 0 C for 14 h.
• the 4-vinylpyridine units contained in the copolymer are reacted by means of 1,3-propane sultone.
• 4.7 g of the copolymer are dissolved in 60 ml of chloroform and 0.826 g of 1, 3-propane sultone, dissolved in 15 ml of chloroform, at room temperature, slowly dropped.
• the reaction mixture is refluxed for 24 h.
• the reaction solution is then washed 3 times with 15 ml of 10% NaCl solution and the polymer was precipitated in methanol, the decanted supernatant solution and the residue dried under reduced pressure at 60 0 C for 14 h.
• the chosen amount of the copolymer is dissolved in 6 ml of n-heptane (or n-hexane, cyclohexane or toluene). 80 mg of an aqueous SiO 2 particle
• Dispersion solids content 30 wt .-%, particle size: 15 nm
• 100 mg of an aqueous Al 2 O 3 particle dispersion solids content 25 wt .-%, particle size: about 50 nm
• 120 mg of a aqueous Ce ⁇ 2 particle dispersion solids content 20 wt .-%, particle size: 10 nm
• the two solutions are mixed together, with no phase separation, and then allowed to stand for a further 3 minutes. After this time, 0.2 ml of H 2 O are added and the resulting mixture is mixed.
• the onset of phase by adding the H 2 O phase is accelerated by cooling the mixture for 10 minutes to 0 0 C.
• the functionalized particles are stable in solution and do not change in diameter over their lifetime, and can be redispersed in nonpolar organic solvents (e.g., n-alkanes, toluene, butyl acetate) without further agglomeration of the functionalized particles.
• nonpolar organic solvents e.g., n-alkanes, toluene, butyl acetate

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• 2006
  • 2006-12-11 DE DE200610058201 patent/DE102006058201A1/de not_active Withdrawn
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