WO2009115506A2 - Metallic nanoparticles stabilised with derivatisied polyethylenimines or polyvinylamines - Google Patents

Abstract

The invention relates to metal-nanoparticles and to methods for the production thereof in which a metallic salt solution is reduced by means of a reducing agent in the presence of the derivatised polyethylenimines or polyvinylamines. Metal salt solutions of two or more different metals can be reduced at the same time or successively. The metallic nanoparticles are obtained from two or more different metals. Metals are preferably silver, palladium and platinum. Suitable reducing agents are, for example, formic acid, formaldehyde, diethanolamine, 5-pentenic acids and sodium borohydride. Silver can be used in the form of silver oxide and/or silver nitrate, palladium can be used in the form of alkali tetrachloropalladate or palladium(ll)nitrate and platinum can be used in the form of alkali tetrachloroplatinate or tetraamine platinum(ll)nitrate.

Description

 Metal nanoparticles stabilized with derivatized polyethylenimines or polyvinylamines

description

The invention relates to metal nanoparticles stabilized with derivatized polyethylenimines or polyvinylamines.

The utility of metallic nanoparticles in a wide variety of applications, such as fibers, paints, films, binders, adhesives, and resins, has been widely documented. Metallic nanoparticles can be used as catalysts or in printing inks, as precursors for printing electronic circuits or for soldering, or they are used because of their special optical, photonic, magnetic or chemical properties. Silver nanoparticles are additionally known for their ability to to rid aqueous solutions of harmful microorganisms. Biotin-bound silver nanoparticles are known as highly sensitive sensors.

A major problem associated with the use of metal nanoparticles is their inherent instability which results in coagulation and, ultimately, precipitation of dendritic metal particles which are significantly larger than 100 nm. This is also disadvantageous for the applications outlined above, in that the nanodisperse system has the highest efficiency, and agglomeration, for example, reduces the catalytic activity or the biocidal effect or leads to an increase in the sintering temperature when used in printing inks. It is also desirable that all nanoparticles are in contact with the surrounding medium to be fully effective.

It is known to stabilize metal nanoparticles against agglomeration and precipitation from liquid media.

A. Dawn et al., Langmuir 2007, 23, 5231 to 5237 describe the preparation of monodisperse silver nanoparticles in the presence of poly-o-methoxyaniline (POMA) as a reducing and stabilizing polymer. An aqueous silver nitrate solution is added to a solution of POMA in chloroform, and the silver nanoparticles are formed at the phase interface. Depending on the aging time (between 8 and 21 days), nanoparticles with a mean diameter between 12.0 and 21, 9 nm are formed. Only very dilute solutions of POMA and silver nitrate are used. T. Sato et al., Macromol. Mat. Eng. 2006, 291, pages 162 to 172, describe the preparation of copolymer-stabilized silver nanoparticles by adding a methanolic silver nitrate solution to a solution of divinylbenzene-ethyl acrylate copolymer in tetrahydrofuran and reduction with NaBH ₄ . The reaction mixture is finally added to methanol and the precipitated silver-containing copolymer is isolated.

J.H. Yeum et al., Fibers and Polymers 2005, Vol. 4, pages 277 to 283 describe the preparation of PMMA / silver nanocomposite microspheres by suspension polymerization of methyl methacrylate in the presence of silver nanoparticles and polyvinyl alcohol as suspending aid. In this case, commercially available aqueous dispersions of silver nanoparticles with diameters of about 15 to 30 nm are used.

J. -W. Kim et al., Polymer 45, 2004, pp. 4741-4747, describe the deposition of colloidal silver on suspension-polymerized microspheres of ethylene glycol dimethacrylate / acrylonitrile copolymer. In this case, an aqueous silver nitrate solution is added to the aqueous copolymer solution and reduced with aqueous hydrazine solution. Porous microspheres with micron particle diameters are obtained which have the silver nanoparticles with diameters in the range of 10 to 50 nm at the inner and outer surfaces. The antibacterial effect of the microspheres is also investigated.

Y. Lu et al., Polymeric Materials: Science & Engineering 2006, 94, pages 264-265 describe metallic nanoparticles embedded in the polymeric network of a core / shell particle. The colloidal core consists of polystyrene, the shell of poly (N-isopropylacrylamide) which is crosslinked by N, N'-methylbisacrylamide. The core / shell particles contain 10.4% by weight of silver nanoparticles in a size of 8.5 ± 1.5 nm. The silver nanoparticles are obtained by reduction of silver nitrate in an aqueous suspension containing the Contains core / shell particles, prepared with sodium borohydride.

Gautam et al., Synthetic Metals, 157 (2007), pp. 5-10, describe the preparation of silver nanoparticles having a particle size in the range of 10 to 30 nm. An aqueous silver nitrate solution is reduced with polyvinyl alcohol (PVA) PVA simultaneously stabilizes the nanoparticles formed. The silver-PVA nanocolloid solution is aged at 2 to 5 ° C for 30 to 50 hours, heated and poured into thin layers of 1 to 5 mm thick. After burning off the polymer at 300 to 400 ⁰ C in air remains a finely divided powder of silver nanoparticles. At silver concentrations of> 5% by weight, agglomeration of the primary particles occurs.

Silver nanoparticles may also be formed by reduction of silver cations in the presence of polyvinylpyrrolidone (PVP) with sodium borohydride, citric acid or sodium citrate as described in Karpov et al., Colloid Journal 2007, Vol. 69, pp. 170-179, and U.S. Pat cited therein.

WO 2005/077329 describes a method in which silver nanoparticles are deposited on the surface of porous polymer particles. The polymer particles are produced by emulsion polymerization in the presence of an emulsifier and stabilizer, preferably gelatin, starch, hydroethyl cellulose, carboxymethyl cellulose, polyvinyl pyrolidone, polyvinyl alkyl ether, polyvinyl alcohol or polydimethylsiloxane / polystyrene block copolymer. The silver nanoparticles are then deposited by reduction of silver salts, for example with hydrazine, LiAIBH ₄ , NaBH ₄ or ethylene oxide. The silver / polymer composite nanospheres are used in cosmetic compositions.

CC. Chen et al., Langmuir 2007, 23, pages 6801-6806 describe the preparation of gold nanoparticles using alkylated polyethylenimines as reducing agents and stabilizers employing a 1,2-epoxydecane-commercialized linear polyethylenimine. The gold particles are prepared by reducing the metal ions, which are in the form of an aqueous solution of HAuCl ₄ , by stirring at room temperature. In this case, the alkylated polyethyleneimine, which is dealkylated by oxidation, acts as a reducing agent and at the same time as a stabilizer for the gold nanoparticles formed.

WO 2004/086044 describes biotin-bound silver nanoparticles as a highly sensitive sensor.

DE 10 2006 017 696 A1 describes a process for the preparation of metal particle sols having a metal particle content of ≥ 1 g / l, in which a metal salt solution containing a solution containing hydroxyl ions, which by dissolving bases such as LiOH, NaOH, KOH, aliphatic or aromatic amines in Water is reacted, and the resulting solution is reduced with a reducing agent in the presence of a dispersant which stabilizes the particles formed, is reduced.

WJ Liang et al., J. CoI. Interf. Be. 2006, 294 (2), 371-375 describe the use of polyethyleneimine / polyoxypropylenediamine copolymer for the preparation of tin nanoparticles. The stabilizing effect is due to the formation of spherical polymer micelles, which is caused by the addition of H ₂ PtCl ₆ . The reduced Pt (O) particles are trapped on the outside of the micelles in the polyethyleneimine block surrounding the polyoxypropylene block.

The processes of the prior art usually lead to systems in which the metal nanoparticles are embedded in the polymer particles and thus can not develop their special properties. Examples of such specific properties are the macroscopic conductivity, the biocidal efficacy, the optical resonance, the magnetic properties, the catalytic properties and the ability to sinter together to form conductive structures of the metal nanoparticles. Also, many of the prior art processes are cumbersome and involve multi-step syntheses and / or sophisticated purification procedures to obtain the final product. Also, with many prior art methods, only a low concentration of metal nanoparticles is obtained.

The object of the present invention is to provide a process for producing metal nanoparticles, which is suitable for producing highly concentrated aqueous solutions of metal nanoparticles, in particular silver, platinum and palladium nanoparticles, without it comes to agglomeration of the metal nanoparticles.

The object is achieved by metal nanoparticles stabilized with derivatized polyethylenimines or polyvinylamines and a process for the preparation thereof, in which a metal salt solution is reduced in the presence of the derivatized polyethylenimines or polyvinylamines with a reducing agent.

Suitable polyethyleneimines or polyvinylamines whose derivatives can be used according to the invention are described below under A to F.

A homopolymers of ethyleneimine (aziridine)

As polyethyleneimines polyethyleneimine homopolymers can be used, which may be present in uncrosslinked or crosslinked form. The polyethyleneimine homopolymers can be prepared by known processes, as described, for example, in Rompps Chemie Lexikon, 8th ed. 1992, pp. 3532-3533, or in Ullmanns Enzyklopadie der Technischen Chemie, 4th edition 1974, Vol. 8, p. 212. 213 and the literature cited therein. They have a molecular weight in the range of approx. 200 to 1,000,000 g / mol. Corresponding commercial products are available under the name Lu pasol ^® from BASF SE or the name Epomin ^® from Nippon Shokubai.

B graft polymers of polyamidoamines with ethyleneimine

Polyethyleneimines for the purposes of the present invention are also polymers comprising ethyleneimine units which are obtainable by grafting polyamidoamines with ethyleneimine. These can be crosslinked with the crosslinkers mentioned under A.

Grafted polyamidoamines are known, for example, from US Pat. No. 4,144,123 or DE-B-2,434,816. The polyamidoamines are obtainable, for example, by condensation of

(I) Polyalkylenpolyaminen, which may be in admixture with diamines, with

(ii) at least dibasic carboxylic acids such as oxalic acid, malonic acid, succinic acid, maleic acid, fumaric acid, itaconic acid, adipic acid, tartaric acid, citric acid, propane tricarboxylic acid, butanetetracarboxylic acid, glutaric acid, suberic acid, sebacic acid, terephthalic acid and their esters, acid chlorides or anhydrides mixed with up to 50 mol% of monobasic amino acids, monohydric hydroxycarboxylic acids and / or monobasic carboxylic acids,

in the molar ratio of (i) to (ii) of 1: 0.5 to 1: 2.

Polyalkylenepolyamines are compounds which contain at least 3 basic nitrogen atoms in the molecule, for example diethylenetriamine, dipropylenetriamine, triethylenetetramine, tripropylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N- (2-aminoethyl) -1,3-propanediamine and N, N 'Bis (3-aminopropyl) ethylene diamine.

Examples of suitable diamines are 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, 1,8-diaminooctane, isophoronediamine, 4,4'-diaminodiphenylmethane, 1,4-bis - (3-aminopropyl) piperazine, 4,9-dioxadodecane-1, 12-diamine, 4,7,10-trioxatridecane-1, 13-diamine or a, z-diamino compounds of polyalkylene oxides. The condensation of the compounds (i) and (ii) takes place as described, for example, in EP-B 0 703 972.

The graft polymers generally contain 10 to 90 wt .-% of polyamidoamines as graft and 90 to 10 wt .-% of ethyleneimine as a graft.

C graft polymers of polyvinylamines with ethyleneimine

Polyethyleneimines for the purposes of the present invention are also polymers containing ethyleneimine units which are obtainable by grafting polyvinylamines with ethyleneimine or oligomers of ethyleneimine. Polyvinylamines are obtained by complete or partial saponification of polymers of open-chain N-vinylcarboxamides of the general formula (I)

(I) where R ¹ , R ² = H or C ¹ to C 6 alkyl,

and are described in more detail under E and F (see below). The saponification degree is generally 5 to 100%. The graft polymers can be crosslinked.

The graft polymers generally contain 10 to 90 wt .-% of polyvinylamine as a graft and 90 to 10 wt .-% of ethyleneimine as a graft.

D Polymers of the higher homologs of ethyleneimine

For the purposes of the present invention, polyethyleneimines also include the polymers corresponding to the compounds listed under A to C of higher homologs of ethyleneimine, such as propyleneimine (2-methylaziridine), 1- or 2-butylenimine (2-ethylaziridine or 2,3-dimethylaziridine ), Understood. However, the polymers of ethyleneimine are preferred.

E At least partial N-vinylcarboxamide homopolymerization Polyvinylamines are at least tesivoten N-Vinyicarbonsäureamid- homo polymers. For their preparation, it is for example of open-chain N-vinylcarboxamides of the above formula (1). Suitable monomers are, for example, N-vinyl formamide (R = R 1 = H in the formula I), N-vinyl-N-methylformamide (R '= methyl, R ^: - H m formula I) ₁ N-vinylacetamide (R') = H, R ^ = methyl in formula I). N-vinyl! -N-meihy! Acelamad (R '= R ^? = Methyl in formula I) and N-vinyl-N-ethyl acetarmd (Ri = ethyl, R ² = methyl in formula I). Preference is given to N-vinylformamide.

F At least teiiverseifte N-Vinyicarbonsäureamid Copoiymerisate

Polyvinylamines in the context of the invention are also the copolymers of (a) 0.1 to 100% by moles of N-vinylcarboxamides of the formula (I) and (b) 0 to 99.9% by moles of Vmyiformsal, Vinyiaeetal, VmylpropionaL Vinyiaikohoi, N-vinyl urea & loff. N-vinylpyrrolidone, N-vinylpiperidone, N-vinylmicrolactam, N, N-divinylideneurea Lind / or N ~ Vinyi ~ Imldazoi. where the sum of (a) and (b) gives 100 moL%, which are at least partially solved.

Preferred polyethyleneimines whose derivatives are used according to the invention are the homopolymers of ethyleneimine described under A and the graft polymers of polyamidoamines described under B with ethyleneimine. Preferred polyethyleneimines and graft polymers of polyamidoamines with ethyleneimine are those having a molecular weight in the range from 500 to 2,000,000 g / mol, more preferably from 1,000 to 100,000 g / mol, in particular from 5,000 to 50,000 g / mol.

The polyethyleneimines or polyvinylamines mentioned under A to F are derivatized by the reactive nitrogen atoms

(1) 1,4-addition (Michael addition) to alpha, beta-unsaturated carbonyl compounds. Suitable alpha, beta-unsaturated carbonyl compounds are acrylic acid and acrylic esters, for example alkyl acrylates and hydroxyalkyl acrylates, methacrylic acid and methacrylic acid esters, for example alkyl methacrylates and hydroxyalkyl methacrylates , Acrolein, arylamide and acrylonitrile;

(2) reaction with compounds nucleophilically substitutable by the imine nitrogen, preferably with hydrocarbon compounds, in particular alkyl compounds or alkylene compounds, which have one or two suitable leaving groups, for example acetate, brosylate, mesylate, nosylate, tosylate, trifluoroacetate, trifluorosulfonate, Chlorine, bromine or iodine; Examples are organic and inorganic halides, in particular alkyl halides, alkyl trifluoroacetates, Al kyl (bromine) toluenesulfonates and alkyl phenates such as methyl chloride, methyl trifluoroacetate, trimethylsilyl chloride and methyl bromotoluene sulfonate; and dihaloalkanes such as 1, 2-dichloroethane, 1, 3-dichloropropane, 1, 4-dichlorobutane and 1, 6-dichlorohexane;

(3) reaction with dialdehydes and / or diketones; suitable dialdehydes and diketones are, for example, glyoxal and 1, 3-pentanedione;

(4) reaction with epoxides, diepoxides, halohydrin ethers and / or bishalohydrin ethers; suitable diepoxides are, for example, 1,6-hexanediol bisglycidyl ether, and also bisglycidyl ethers of oligo- and polyethylene glycols; as well as reaction products of halohydrins, for example epichlorohydrin, with alkylene glycols and polyalkylene glycols having from 2 to 100 ethylene oxide or propylene oxide units;

(5) reaction with alkylene carbonates, for example ethylene carbonate or propylene carbonate, and bischloroformates, for example 2,2-dimethylpropylene-bischloroformate;

(6) reaction with polyalkylene glycol ethers;

(7) reaction with carboxylic acids and carboxylic acid esters in an amidation reaction;

(8) reaction with isocyanates; for example with diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate and diphenylmethane diisocyanate;

(9) reaction with formaldehyde and cyanide salts in a Strecker reaction;

(10) Reaction with formaldehyde and further reaction of the imines formed with further components by Strecker reaction, Mannich reaction or Eschweiler

Clarke reaction, carboxymethylation or phosphonomethylation.

Several derivatization reactions can be combined with each other. In this case, relatively high molecular weight polymers are obtained by crosslinking with polyfunctional compounds.

Preferred derivatization reactions are (1) 1,4-addition (Michael addition) to alpha, beta-unsaturated carbonyl compounds;

(4) reaction with diepoxides;

(8) Reaction with carboxylic acids or carboxylic acid esters.

In a specific embodiment, polyethyleneimines A are reacted with a diepoxide and / or bischlorohydrin ether and then reacted with one or more alpha, beta-unsaturated carbonyl compounds; for example, they are reacted with 1,6-hexanediol bisglycidyl ether or the bisglycidyl ether of a polyalkylene glycol and then reacted with (meth) acrylic acid, alkyl (meth) acrylate, for example methyl acrylate, and / or hydroxyalkyl (meth) acrylate, for example hydroxyethyl acrylate or 4-hydroxybutyl acrylate.

Preferred alkyl (meth) acrylates are the C ₁ -C ₆ -alkyl (meth) acrylates, preferred hydroxyalkyl (meth) acrylates are the hydroxy-C ₁ -C ₆ -alkyl (meth) acrylates.

In a further specific embodiment, polyethyleneimines A are reacted with a diepoxide and / or bischlorohydrin ether and subsequently reacted with a carboxylic acid ester, for example ethyl acetate.

In a further specific embodiment, polyethyleneimines A are reacted with acrylic acid, hydroxyalkyl acrylates, for example hydroxyethyl acrylate or 4-hydroxybutyl acrylate, and / or acrylamides, for example N-tert-butylacrylamide or N-isopropylacrylamide or other N-substituted acrylamides.

Preferred acrylamides are the N-Ci-C ₆ -alkylacrylamides.

In a further specific embodiment, polyamidoamines B are reacted with acrylic acid.

In a further specific embodiment, polyamidoamines B are reacted with a diepoxide and / or bischlorohydrin ether, for example the bisglycidyl ether of a polyalkylene glycol, and then reacted with acrylic acid.

The derivatization of the polyalkyleneimines is generally carried out at temperatures of - 30 ⁰ C to 300 ⁰ C in the gas phase, optionally under pressure, or in solution. The derivatization is preferably carried out in the same medium in which the preparation of the nanoparticles has also taken place. It is preferred at temperatures from 50 to 150 ⁰ C, in particular carried out at 75 to 95 ° C. Preferred reaction medium is water.

The metal nanoparticles are generally prepared by reduction of the corresponding metal salts with a reducing agent in the presence of the derivatized polyalkyleneimines or polyvinylamines. Suitable reducing agents may be organic or inorganic reducing agents. Examples are alcohols such as methanol or ethanol, amino alcohols such as 1, 2-aminoethanol, diethanolamine, aldehydes such as formaldehyde or acetaldehyde, ketones, carboxylic acids such as formic acid, acetic acid or oxalic acid, alkenoic acids such as 5-pentenoic acid, hydrazine or hydrazine derivatives, azo compounds such as AIBN (azobisisobutyronitrile), carboxylic anhydrides, amides, amines, ethers, esters, alkenes, dienes, thio compounds, mono- or polysaccharides, phosphorus or arsenic derivatives, hydrogen or carbon oxides. Suitable inorganic reducing agents are hydrogen, metals such as zinc, calcium and magnesium, and metal hydrides such as sodium borohydride, furthermore Sn (II) salts, Fe (II) salts, thiosulfates, thiosulfites, phosphites, phosphines, sulfides and disulfides.

Preference is given to formic acid, formaldehyde, diethanolamine, methanol, ethanol, 5-pentenoic acid, ascorbic acid, citric acid, lactic acid, oxalic acid, glucose, fructose and sodium borohydride. Particularly preferred organic reducing agents are formic acid or formaldehyde. This produces carbon dioxide, which can be easily removed from the reaction mixture. For example, carbon dioxide can be removed from the reaction mixture by stripping with air. Also particularly preferred are diethanolamine, 5-pentenoic acid, ascorbic acid and citric acid. Also preferred are ethanol, methanol, ethylene glycol, diethylene glycol, hydrazine and oxalic acid.

Preferred inorganic reducing agents are sodium borohydride, Sn (II) salts, Fe (II) salts, thiosulfates, thiosulfites, phosphites, phosphines, sulfides and disulfides.

In one embodiment of the process according to the invention, an alcohol is used both as a solvent and as a reducing agent. In addition to the alcohol, no further reducing agent is used. This method is basically described in Atf. Funct. Mater. 2003, 13 No.2: Synthesis of nanoscaled ZnO particles by thermolysis of metal salt precursor in diethylene glycol; J. Mater. Res. Vol. 10, no. 1: Synthesis of spherical ZnO nano particles by the hydrolysis of Zn acetate in diethylene glycol; J. SoI-GeI Be. Techn. 2004, 29, 71 - 79: Synthesis of monodisperse ZnO spheres with diameter of 5-10 nm via heating of Zn acetate in methanol, ethanol and 2-methoxyethanol. In contrast to the procedures described there, According to the reduction in the presence of derivatized polyethylenimines or polyvinylamines as additional stabilizers performed.

The metal nanoparticles are generally prepared by reduction at temperatures of - made 30 to 300 ° C and pressures between 10 mbar and 100 bar, preferably at temperatures of 0 to 100 ⁰ C, particularly preferably at 20 to 95 ° C. Preferably, working at atmospheric pressure, so that special vacuum devices or pressure vessels are not required.

For example, the temperature of the reduction of the metal salt solution can be selected so that the reaction is completed at the latest after 24 hours, preferably at the latest after 10 hours, and in particular after 5 hours at the latest. For example, this temperature may be in the case of silver as metal and formic acid as a reducing agent of 30 to 50 ⁰ C.

The metal nanoparticles stabilized according to the invention can consist of copper, silver, gold, palladium, nickel, platinum, rhodium, iron, bismuth, iridium, ruthenium or rhenium or also of two or more of these metals. These metals may be in the form of their oxides, nitrates, phosphates, sulfates, sulfites, phosphonites, nitrites, borates, aluminates, silicates, cyanides, isocyanates, thioisocyanates, halides, perchlorates, periodates, perbromates, chlorates, iodates, bromates, hypochlorites or even in Form of complex compounds are present. Examples of suitable complex compounds are silver-ammonia complexes, diaminodichloropalladate, tetrachloropalladate or tetrachloroplatinate. It is also possible to use salts of a plurality of different metals which can be reduced simultaneously or in succession.

Preferred metals are copper, silver, gold, nickel, palladium, platinum, cobalt, rhodium, iridium, iron, ruthenium and osmium. Particularly preferred are copper, silver, palladium and platinum. Silver is used, for example, in the form of silver oxide, silver acetate, silver nitrate or a silver oxide / silver nitrate mixture, palladium as alkali metal tetrachloro palladate, palladium (II) nitrate, palladium (II) acetate, tetraaminopalladium (II) nitrate, ammonium hexachloropalladate (IV), Diaminopalladium (II) chloride, bis (triphenylphosphine) palladium (II) chloride, bis (2,4-pentanedionato) palladium (II), 1,2-bis (diphenylphosphino) -ethanadium palladium (II) chloride, bis-triphenylphosphine palladium (II ) chloride, platinum as the alkali metal tetrachloroplatinate, bis (2,4-pentanedionato) platinum (II), hexachloroplatinic (IV) acid hydrate, tetraamine platinum (II) chloride, platinum (IV) nitrate, tetraamine platinum (II) nitrate, Platinum (II) acetate and rhodium as Hexachlorrhodium (lll) acetate, rhodium (III) acetate, rhodium (III) oxyhydrate, chorotrisis (triphenyl) phosphinrhodium (l) or acetylacetonato (cyclooctadiene) rhodium (l) used. The reduction can be carried out in organic solvents such as alcohols, polyols, esters, chlorinated hydrocarbons, phenols, DMSO, DMF, NMP and ethers such as THF, dioxane or dioxolane. Other reaction media are conceivable, such as molten salts or ionic liquids. Preferred solvent Water or aqueous-organic solvent mixtures, glycol and diethylene glycol, particularly preferred are water and aqueous-organic solvent mixtures.

If the reduction is carried out in an alcohol, the alcohol can act as a reducing agent. Suitable monohydric alcohols are ethanol, methanol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, t-butanol, n-pentanol, i-pentanol, 2-methylbutanol, sec-pentanol, t-butanol. Pentanol, 3-methoxybutanol, n-hexanol, 3-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, 3-heptanol, n-octanol, 2-ethylhexanol, sec-octanol, n-nonyl alcohol, 2, 6-dimethylheptanol-4, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol and diacetone alcohol. Preferred monohydric alcohols are selected from glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, Ethylenglykolmonopropyl- ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, Ethylenglykolmo- nophenylether, ethylene glycol mono-2-ethylbutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, Diethylenglykolmonopropylether, Diethylenglykolmo- nobutylether, diethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene lenglykolmonoethylether, Propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether and dipropylene glycol monopropyl ether.

Preference is given to polyhydric alcohols, for example diols, which are preferably selected from the group consisting of 1, 2-ethanediol, 1, 2-propanediol, 1, 3-propanediol, 1, 2-butanediol, 1, 3-butanediol, 2.3 Butanediol, 1, 4-butanediol, but-2-en-1, 4-diol, 1, 2-pentanediol, 1, 5-pentanediol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 1 , 2-hexanediol, 1, 6-hexanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3-hexanediol, octanediol, 1, 10-decanediol, 1, 2-dodecanediol, 1 , 12-dodecanediol, neopentyl glycol, 3-methylpentan-1, 5-diol, 2,5-dimethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,2-cyclohexanediol, 1,4 Cyclohexanediol, 1,4-bis (hydroxymethyl) cyclohexane, hydroxylpivaloic acid neopentylglycol monoester, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis [4- (2-hydroxypropyl) phenyl] propane, diethylene glycol, dipropylene glycol, Triethylene glycol, tetraethylene glycol, tripropylene glycol, tetrapropylene glycol, 3-thiopentane-1, 5-diol, polyethylene glycols, polypropylene glycols and polytetrahydrofura n having a molecular weight of 200 to 10,000, diols based on block copolymers such as ethylene oxide / propylene oxide copolymers or polymers containing ethylene oxide or propylene oxide groups.

Other suitable diols are polyether homopolymers having OH functionality such as polyethylene glycol, polypropylene glycol and polybutylene glycol, binary copolymers such as ethylene glycol / propylene glycol and ethylene glycol / butylene glycol copolymers, non-branched ternary copolymers such as ethylene glycol / propylene glycol / ethylene glycol, propylene glycol / ethylene glycol / Propylene glycol and ethylene glycol / Buylenglykol / ethylene glycol copolymers. Other suitable diols are polyether block copolymers having OH functionality, such as binary block copolymers, such as polyethylene glycol / polypropylene glycol and polyethylene glycol / polybutylene glycol, non-branched ternary block copolymers with alkyl chains, such as polyethylene glycol / polypropylene glycol / polyethylene glycol, polypropylene glycol / polyethylene glycol / polypropylene glycol and polyethylene glycol / polybutylene glycol / polyethylene glycol terpolymers. Further suitable polyethers are described in DE 102 97 544, paragraphs [0039] to [0046].

The use of polyhydric alcohols having less than 10 carbon atoms is particularly preferred, especially those which are liquid at 25 ° C. and 1013 mbar, for example ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1, 2-butanediol, 1, 3-butanediol, 1, 4-butanediol, 2,3-butanediol, pentanediol, hexanediol and octanediol, with ethylene glycol and 1, 2-propanediol are particularly preferred.

Suitable polyhydric alcohols are furthermore triols, for example 1,1,1-tris (hydroxymethyl) ethane, 1,1,1-tris (hydroxymethyl) propane, 2-ethyl-2-hydroxymethyl-1,3-propanediol, 1, 2,6-hexanetriol, 1, 2,3-hexanetriol and 1, 2,4-butanetriol.

Furthermore, sugar alcohols such as glycerol, threitol, erythritol, pentaerythritol and pentitol can be used.

The derivatization of the polyethyleneimines or polyvinylamines and the preparation of the nanoparticles can be carried out as a so-called one-pot reaction without isolation of intermediates in one and the same reaction medium. In this case, the polyethylenimine or polyvinylamine is first derivatized by reaction with the derivatizing agent (s), and then the metal nanoparticles are generated in the presence of the derivatized polyethylenimines or polyvinylamines by adding metal salt and reducing agent. It is also possible to reduce metal salt solutions of two or more different metals simultaneously or in succession, metal nanoparticles of two or more different metals being obtained. be. In this case, successive reduction steps can be carried out with different reducing agents.

The invention is further illustrated by the following examples.

Examples of characterization

The metal nanoparticles prepared below were characterized as follows:

UV-vis spectra were recorded between 200 and 800 nm using a Hewlett-Packard 8453 spectrometer in absorption mode in 1 cm glass cuvettes, with a suitable dilution selected.

TE M images were generated using a FEI CM120 device operating at 100kV, and the result was captured using a Gatan bioscan digital camera.

DLS (Dynamic Light Scattering) spectra were recorded on a Malvern ZetasizerNano S device at 23 ° C and at an angle of 173 °. The evaluation of the measurement data was carried out according to ISO standard 13321: 1996E. The obtained autocorrelation function was logarithmized and approximated with a third order polynomial. The mean z-value was calculated from the quadratic coefficients using temperature, viscosity, refractive index and laser light wavelength as constants in the Stokes-Einstein relation. The distribution was calculated using the Malvern software (CONTIN procedure by S. Provencher).

Synthesis of the polyethylenimine derivatives

Starting from polyethyleneimine having a weight-average molecular weight M _w of 25,000 g / mol, derivatives were prepared. The synthesis of the derivatives was carried out in aqueous solution. The determination of the sales was carried out by NMR spectroscopy, HPLC, GC (methacrylic acid and its esters) and Preußmann test (Epoxies, R. Preußmann, Arzneimittel-Forschung 1969, 19, pages 1059 to 1073). The characterization of the products was carried out by determining the K value of 1% strength by weight solutions according to Fikentscher (H. Fikentscher, Cellulose Chemistry 1932, 13, pages 58 to 64). To determine the solids (FG), the samples were dried for 2 hours at 120 ^° C. under reduced pressure. The yields are based on the amounts of substance used. example 1

750 g of a 56% strength aqueous solution of polyethyleneimine (M _w = 25,000) are placed in a four-necked flask with intensive stirrer and reflux condenser and heated to an internal temperature of 95 ° C. with stirring. This air is constantly introduced. When the temperature of 95 ° C is reached, 280.8 g of acrylic acid are added dropwise within 2 hrs. At the same time, 280.8 g demineralized water are added dropwise in 2 hours. Thereafter, the experiment is stirred for 6 hrs. At 95 ° C. The experiment is cooled to 80 ^° C. and diluted with a further 200 ml of water. The product is a yellow, clear solution. The K value is 27.9; Solids content (FG): 42%; Yield: 99%.

Example 2

150 g of a 56% aqueous solution of polyethyleneimine (M _w = 25,000) and 202.3 g of demineralized water are introduced into a four-necked flask with intensive stirrer and reflux condenser and heated to an internal temperature of 95 ° C. with stirring. This air is constantly introduced. When the temperature of 95 ° C is reached, 70.3 g of acrylic acid are added dropwise within 2 hrs. At the same time, 280.8 g demineralized water are added dropwise in 2 hours. Thereafter, the experiment is stirred for 6 hrs. At 95 ° C. The product is a slightly yellow, viscous solution. The K value is 17.65 (1% in H ₂ O); Sales: 100%; FG: 37.7%.

Example 3

150 g of a 24.9% aqueous solution of polyethyleneimine (M _w = 25,000, crosslinked with 4.55% bis-glycidyl ether of a polyethylene glycol of average molecular weight of 2000) and 202.3 g of demineralized water are placed in a four-necked flask with intensive stirrer and reflux condenser and heated with stirring to an internal temperature of 95 ° C. This air is constantly introduced. When the temperature of 95 ° C is reached, 66.5 g of acrylic acid are added dropwise within 2 hrs. Thereafter, the experiment is stirred for 6 hrs. At 95 ° C. The product is a slightly yellow, viscous solution. The K value is 21, 97; Yield: 100%; FG: 39.8% (after 2 hrs. At 120 ⁰ C in vacuo).

Example 4

100 g of a 56% strength aqueous solution of polyethyleneimine (M _w = 25,000) and 134.9 g of demineralized water are introduced into a four-necked flask with intensive stirrer and reflux condenser and heated to an internal temperature of 75 ° C. with stirring. This air is constantly introduced. When the temperature of 75 ° C is reached, a mixture of 65.61 g of acrylic acid and 1 1, 19 g of methyl acrylate is added dropwise within 2 hours via a dropping funnel. Thereafter, the experiment is stirred for 5 hrs. At 95 ° C and then heated to 95 ° C for about 3 hrs. The product is a slightly orange colored, viscous solution. The K value is 19.1; FG: 42.0%; Yield (acrylic acid): 90%; Yield (methacrylate): 85%.

Example 5 100 g of a 56% strength aqueous solution of polyethyleneimine (M _w = 25,000) and 134.9 g of demineralized water are placed in a four-necked flask with intensive stirrer and reflux condenser and heated to an internal temperature of 75 ° C. with stirring. This air is constantly introduced. When the temperature of 75 ° C is reached, a mixture of 70.29 g of acrylic acid and 5.60 g of methyl acrylate is added dropwise within 2 hours via a dropping funnel. Thereafter, the experiment is stirred for 5 hrs. At 95 ° C and then heated to 95 ° C for about 3 hrs. The result is a very viscous, clear, yellow solution. The K value is 17.3 (1% in H ₂ O); FG: 42.96% (after 2 hrs. At 120 ⁰ C in vacuo); Yield (acrylic acid): 96%; Yield (methacrylate): 99.5%.

Example e

100 g of a 56% strength aqueous solution of polyethyleneimine (M _w = 25,000) and 134.9 g of demineralized water are introduced into a four-necked flask with intensive stirrer and reflux condenser and heated to an internal temperature of 75 ° C. with stirring. This air is constantly introduced. When the temperature of 75 ° C is reached, 56.23 g of acrylic acid within 90 minutes via a dropping funnel. added dropwise. Subsequently, 22.38 g of methyl acrylate within 30 min. added dropwise. Thereafter, the experiment is stirred for 5 hours at 75 ° C and then heated to internal temperature: 95 ° C for about 3 hrs. The result is a very viscous, clear, yellow solution. The K value is 16.2; FG: 41, 4%. Yield (acrylic acid): 97%; Yield (methacrylate): 97%.

Example 7

According to the procedure specified in US Pat. No. 4,144,123, Example 3, a polyamidoamine is prepared by condensing adipic acid with diethylenetriamine and subsequently grafted in aqueous solution with sufficient ethyleneimine so that the polyamidoamine per grafted nitrogen atom group contains 6.7 grafted ethyleneimine units. 321 g of a 62% aqueous solution of this polymer are placed in a four-necked flask with intensive stirrer and reflux condenser, diluted with 479 g of demineralized water and heated with stirring to an internal temperature of 95 ° C. This air is constantly introduced. When the internal temperature of 95 ° C is reached, 87 g of acrylic acid are added dropwise within 2 hrs. Thereafter, the experiment is stirred for 6 hrs. At 95 ° C. The experiment is cooled to 80 ^° C. and diluted with a further 200 ml of water. The product is a yellow, clear solution. K value: 21, 2; FG: 32.6%; Yield (acrylic acid): quantitative. Example 8

430 g of polyethyleneimine (M _w = 25,000) are placed in a four-necked flask equipped with a water separator, sparged with nitrogen and heated to 80 ^° C. with stirring. 600 g of acetic acid and 100 g of demineralized water are weighed into a dropping funnel and added slowly. Thereafter, the reaction mixture is slowly heated to an internal temperature of 160 ⁰ C and thereby distilled off water / acetic acid. After the internal temperature is 160 ⁰ C, the mixture for 1 hr. 30 min. stirred at 160 ⁰ C. Thereafter, the last residues of water / acetic acid are removed in vacuo. The product is bottled hot in glass bottles.

Example 9

100 g of a 56% strength aqueous solution of polyethyleneimine (M _w = 25,000) and 134.9 g of demineralized water are introduced into a four-necked flask with intensive stirrer and reflux condenser and heated to an internal temperature of 55 ° C. with stirring. When the temperature of 55 ° C is reached, are added via a dropping funnel 13 g of epoxyhexane via a syringe within 30 min. added. Now air is introduced. Thereafter, 65.6 g of acrylic acid are added via a dropping funnel within 2 hrs. The experiment is first stirred at 60 ⁰ C, then heated to 90 ⁰ C. After 12 hours of stirring, the reaction is complete. The result is a very viscous, clear, red solution. FG: 43.58%; Yield (acrylic acid): 99.3%.

Example 10

254.1 g of polyethyleneimine (M _w = 25,000) are weighed into a 1 l four-necked flask with intensive stirrer and reflux condenser, heated and stirred. Within 1 hr. 408.25 g of ethyl acetate are added dropwise and then the temperature is raised to 45 ° C.

This is followed by a slow increase in temperature up to 60 ^° C. After 7 hours, ethyl acetate and ethanol are distilled off from the reaction mixture. The viscous product is again heated to 60 ° C and mixed with 287.1 g of ethyl acetate. Now the experiment is heated to reflux and 8 hrs. 30 min. held backflow.

Subsequently, ethyl acetate and ethanol are distilled off.

Example 11

According to the method specified in US Pat. No. 4,144,123, Example 3, a polyamidoamine is prepared by condensation of adipic acid with diethylenetriamine and subsequently grafted in aqueous solution with sufficient ethyleneimine so that the polyamidoamine per grafted nitrogen atom contains 6.7 grafted ethyleneimine units. 362 g of a 62% aqueous solution of the polyamidoamine are placed in a four-necked flask with intensive stirrer and reflux condenser, with 540 g of deionized water diluted and heated with stirring to an internal temperature of 95 ° C. This air is constantly introduced. When the internal temperature of 95 ° C is reached, 98.1 g of acrylic acid are added dropwise within 2 hrs. Thereafter, the experiment is stirred for 12 hours at 95 ° C. The experiment is cooled to 80 ⁰ C and diluted with another 200 ml of water. The product is a viscous yellow solution. K value: 20.8; FG: 32.78%; Yield (acrylic acid): 99.7%.

Example 12

750 g of a 56% strength aqueous solution of polyethyleneimine (M _w = 25,000) are placed in a four-necked flask with intensive stirrer and reflux condenser and heated to an internal temperature of 95 ° C. with stirring. This air is constantly introduced. When the internal temperature of 95 ° C is reached, 280.8 g of acrylic acid are added dropwise within 2 hrs. At the same time, 280.8 g demineralized water are added dropwise in 2 hours. Thereafter, the experiment is stirred for 6 hrs. At 95 ° C. The experiment is cooled to 80 ^° C. and diluted with a further 200 ml of water. The product is a yellow, clear solution. K value: 27.9; FG: 41, 84%; Yield (acrylic acid): 99%.

Example 13

355 g of a 56% aqueous solution of polyethyleneimine (M _w = 25,000) and 178.4 g of deionized water are placed in a four-necked flask with intensive stirrer and reflux condenser and heated to an internal temperature of 95 ° C. with stirring. This air is constantly introduced. When the internal temperature of 95 ° C is reached, 166.6 g of acrylic acid are added dropwise within 2 hrs. Thereafter, the experiment is stirred for 6 hrs. At 95 ° C. The experiment is cooled to 80 ^° C. and diluted with a further 200 ml of water. The product is a yellow, viscous solution. K value: 16.3; FG: 38.13%. Yield (acrylic acid): 99%.

Example 14

425.8 g of a 56% aqueous solution of polyethyleneimine (M _w = 25 000) and 525.6 g of demineralized water are placed in a four-necked flask with intensive stirrer and reflux condenser and heated with stirring and nitrogen inlet to an internal temperature of 55 ° C. Subsequently, 48.6 g of a 22.3% aqueous solution of a bis-glycidyl ether of a polyethylene glycol of average molecular weight of 2000 within 10 min. dropwise. Then the temperature is increased with continuous passage of air to 95 ° C, and 199.5 g of acrylic acid are added dropwise within 2 hrs. Thereafter, the experiment is stirred for 6 hrs. At 95 ° C. The product is an orange, viscous solution. The K value is 18.2; FG: 38.8%; Yield (acrylic acid): 99.59%. Example 15

According to the method specified in US Pat. No. 4,144,123, Example 3, a polyamidoamine is prepared by condensing adipic acid with diethylenetriamine and subsequently grafted in aqueous solution with sufficient ethyleneimine so that the polyamidoamine per grafted nitrogen atom contains 6.7 grafted ethyleneimine units. This product is crosslinked by reaction with a single bismuth glycidyl ether of a polyethylene glycol of average molecular weight 2000 as described in Example 3 of US-A 4,144,123. An ethyleneimine unit-containing polymer having a broad molecular weight distribution (polydispersity of 400) is obtained. 800 g of a 24% aqueous solution of this stage are placed in a four-necked flask with intensive stirrer and reflux condenser and heated with stirring to an internal temperature of 95 ° C. This air is constantly introduced. When the temperature of 95 ° C is reached, 106.9 g of acrylic acid are added dropwise within 2 hrs. Thereafter, the experiment is stirred for 6 hrs. At 95 ° C. The product is a viscous, slightly cloudy, orange solution. K value: 50.3; FG: 31, 74%; Yield (acrylic acid): 98%.

Examples 16 to 32

The following examples show the broad applicability of the functionalization reaction. The reactions were carried out in a 100 L stainless steel reactor. Polyethyleneimine is introduced into the reactor and heated to 95.degree. The reactants are added over a period of 2 hours with vigorous stirring. The reaction mixture is then cooled to 25 ° C and analyzed unreacted reactants with headspace GC. In all cases, high sales are achieved.

Table 1

"PEI = polyethyleneimine, as a 25% solution in water

^* AA = acrylic acid

^* HEA = hydroxyethyl acrylate

^* 4-HBA = 4-hydroxybutyl acrylate

Examples 33 to 50

The reactions are carried out as described for Examples 16 to 32.

Table 2

^* TBAM = N-tert-butylacrylamide, 20% by weight in THF

^* AIPA = acrylic acid isopropylamide, 20% by weight in water

Example 51

1 11, 43 g of a 52.54 wt .-% aqueous solution of polyethyleneimine (M _w = 25 000 g / mol, crosslinked with 4.55% bisglycidyl ether of a polyethylene glycol having an average molecular weight of 2000 g / mol) and 201, 4 g of deionized water are placed in a four-necked flask with an intensive stirrer and reflux condenser and heated to 95 ^° C. with stirring. This air is continuously introduced. Once the temperature has reached 95 ° C, 73.54 g of 4-acryloylmorpholine are added dropwise over a period of 2 hours. The mixture is then stirred for a further 6 hours at 95 ° C and finally diluted with 139.7 g of deionized water. The product is an orange-colored, viscous solution with a solids content of 25.57%. Example 52

100 g of a 56 wt .-% aqueous solution of polyethyleneimine (M _w = 25 000 g / mol) and 400 g of deionized water are placed in a four-necked flask equipped with an intensive stirrer and reflux condenser and heated to 95 ° C with stirring. In the process, air is continuously introduced. Once the temperature reaches 95 ° C, 84.98 g of 2-

Acrylamidoglycolic acid added dropwise over a period of 2 hours.

At the same time, 100 g of deionized water are added dropwise over a period of 2 hours. The mixture is then further stirred at 95 ° C for 6 hours.

The product is a dark, red-brown, viscous solution with a solids content of 17.42%. The turnover is 100%.

Example 53

100 g of a 56 wt .-% solution of polyethyleneimine (M _w = 25 000 g / mol) and 325.94 g of deionized water are placed in a four-necked flask with an intensive stirrer and reflux condenser and heated to 95 ° C with stirring. This air is continuously introduced. Once the temperature has reached 95 ° C, 36.77 g of 4-acryloylmorpholine are added dropwise over a period of 2 hours. The mixture is then further stirred at 95 ° C for 6 hours. The product is a yellow solution with a solids content of 20.54%. The turnover is 100%.

Example 54

800 g of a 24 wt .-% aqueous solution of Lupasol ^® SK (M _w = 2 million g / mol) are introduced into a four-necked flask equipped with intensifier bar and reflux condenser and heated with stirring to 95 ° C. In this case, continuous air is introduced. Once the temperature has reached 95 ° C, 106.92 g of acrylic acid are added dropwise over a period of 2 hours. The mixture is then further stirred at 95 ° C for 6 hours. The product is an orange, viscous solution with a solids content of 31, 7%. The turnover is 100%.

Example 55

100 g of a 56 wt .-% solution of Lupasol ^® HF (M _w = 25 000 g / mol) and 134.86 g of deionized water are placed in a four-necked flask with an intensive stirrer and reflux condenser and heated to 95 ° C with stirring. This air is continuously introduced. As soon as the temperature has reached 95 ° C., 56.23 g of acrylic acid are distributed dropwise over a period of 1 hour and 26 minutes, and then 22.38 g of methyl acrylate are added in 34 minutes. The mixture is then further stirred at 95 ° C for 6 hours. The product is an orange, viscous solution with a solids content of 41.4%. The conversion is 100%, the K value 16.2. Example 56

7.5 parts of polyethyleneimine (M _w = 25 000 g / mol) are added as a 50 wt .-% solution in water to 4 parts of water and heated to 45 ° C. To the mixture is added 3 parts of a silver nitrate solution (500 g / L silver nitrate in water) followed by 4.1 parts of formic acid (55 g / L in water) or sodium borohydride solution (42 g / L in water). An orange solution and a white precipitate are formed. The UV-vis spectrum shows no absorption band in the range between 300 and 900 nm. As a result, no stable silver nanoparticles have been formed.

Example 57

20 parts of the polymer solution from Example 6 were placed in a glass reactor. With stirring, 42 parts of a silver nitrate solution was added over a period of 10 minutes. The resulting white pasty mass was heated to 40 ⁰ C within 30 minutes. Subsequently, 6 parts of 98% formic acid were slowly added. A vigorous CO ₂ evolution could be observed. After 24 h, the reaction was complete and the reactor contents were cooled to room temperature. The dark pasty mass at the reactor bottom was separated by decantation. The product had a silver content of 43% by weight. TEM analysis showed separate particles of silver crystallites on the surface of the polymer particles in contact with the reaction medium. A TEM image is shown in FIG.

Example 58

10 parts of the polymer solution from Example 14 were initially charged in a glass reactor. While stirring, 20 parts of a silver nitrate solution within 2 min. added. The obtained solid white pasty mass was within 20 min. heated to 40 ⁰ C. Subsequently, 3 parts of a 98 wt .-% formic acid were slowly added with vigorous stirring. As a result, CO ₂ evolution was observed. After 2 hours, another 30 parts of silver nitrate solution were added, then 4.5 parts of formic acid were added slowly. The reaction was continued for 16 hours. Then the reactor contents were cooled to room temperature. The dark pasty mass at the reactor bottom was isolated by decantation. The product had a silver content of 55 wt .-%, the supernatant contained 38 wt .-% silver. The TEM analysis showed separate particles with silver crystallites on the surface of the polymer particles which were in contact with the medium. Diluting the pasty mass by a factor of 100,000 with water did not precipitate silver, reflecting the high colloidal stability of these polymer-silver particle complexes. The original UV-vis spectrum with a Maximum at 410 nm and a small shoulder at 470 nm was retained. A TEM image is shown in FIG.

Example 59 In a glass reactor, 26.1 parts of silver oxide were suspended in 5 parts of the solution of Example 3. 3.5 parts of a 98% by weight formic acid were added all at once. A vigorous gas evolution was observed, at the same time the reaction mixture turned dark. Finally, the mixture was heated to 40 ⁰ C and left for 30 minutes at this temperature. The isolated dark brown pasty mass had a peak in the UV-vis spectrum at 410 nm, which is characteristic for small silver nanoparticles.

Example 60

In a glass reactor, 4 parts of silver oxide and 1 part of silver nitrate solution are suspended in a part of the solution of Example 14. Another 4 parts of the polymer solution of Example 14 are added in two equal portions, forming an off-white mixture. This is heated to 40 ⁰ C, and there are added 1, 5 parts of formic acid in 5 portions. After 2 hours the reaction is complete and the mixture is cooled to room temperature. The isolated dark brown pasty mass has a peak in the UV-vis spectrum at 410 nm, which is characteristic of small silver nanoparticles on.

Example 61

In a glass reactor, 1 part of the solution from Example 14 is diluted with 5 parts of water. A mixture of 4 parts silver oxide and 1 part silver nitrate is added and the mixture is heated to 40 ° C. Then 1.5 parts of formic acid are added in 5 portions. Finally, another 4 parts of the solution of Example 14 are added in two equal portions, forming an off-white mixture. This is heated to 40 ⁰ C. After 2 hours, the reaction is complete. The resulting dark solution has a peak in the UV-vis spectrum at 410 nm.

Example 62

In a glass reactor, 1 part of the solution of Example 14 and 2 parts of water are mixed. 4 parts of silver oxide and 1 part of silver nitrate are added to the mixture. Subsequently, 1.5 parts of formic acid are added in 5 portions. Subsequently, a further 4 parts of the solution from Example 14 are added in 2 equal portions. A whitish mixture is formed. This is heated to 40 ° C. After 2 hours, the reaction is complete. The resulting dark solution has a peak in the UV-vis spectrum at 410 nm. Example 63

In a glass reactor, 1 part of the solution from Example 14 is heated to 40 ⁰ C. 3.9 parts of silver acetate, followed by 1.5 parts of formic acid are added. After 2 hours of reaction, the reaction is complete. A dark pasty mass with a silver content of 62% by weight is obtained. The UV-vis spectrum shows a maximum at 410 nm. A solution diluted by a factor of 100,000 with water gives the same spectrum.

Example 64

A solution of the pasty mass from Example 58 with a silver content of 2 wt .-% is applied with a doctor blade to a glass substrate and dried at room temperature or at 250 ⁰ C in a vacuum. A film of 200 μm thickness is obtained. The dried at room temperature film can be redissolved in water. The dried at 250 ° C film has an electrical resistance of 2 MΩ over a length of 4 cm. After treatment in air at 300 ^° C. for 2 hours, a conductive film of sintered silver particles having a resistance of less than 1 Ω over a length of 4 cm is obtained.

Examples 65 to 133

General working instructions

Procedure A: x parts of water and y parts of aqueous silver nitrate solution (500 g / L) are placed in a reactor. The mixture is shaken at 500 rpm and heated to the reaction temperature of 45 ° C. The polymer solutions of Examples 1 to 6, 9, 1 1 and 16 to 29 are added at once. In some cases, a white precipitate is formed. Subsequently, a stoichiometric amount, based on the metal content, of formic acid (51 g / L) is added all at once.

Procedure B:

Like Procedure A, but the formic acid is added in 40 equal portions, evenly distributed over a period of 2 hours.

Procedure C:

Like Procedure A, but using an aqueous formaldehyde solution at a concentration of 33 g / L. Procedure D:

As procedure B, but using the aqueous formaldehyde solution.

FIG. 3 shows a TE M pick-up of example 74. FIG. 4 shows a TE M pick-up of example 84.

Table 3

Continuation Table 3

Continuation Table 3

Continuation Table 3

Continuation Table 3

w

Examples 135 and 136

The product of Example 3 (7.5 parts) having a solids content of 50 g / l was heated to 45 ° C. 5 parts of a solution of potassium tetrachloropalladate (100 g / l) were added all at once. A white precipitate forms, which slowly dissolves again during the reaction. Subsequently, a solution of sodium borohydride in water (4.1 parts containing 42 g / l sodium borohydride) was added. The reaction mixture was stirred for 4 hrs, taking a black color. TEM analysis showed the presence of metal nanoparticles. In another approach (Example 98), the sodium borohydride solution was added in 4 portions. The result was the same. A TE M Auf would take the polymer particles Figure 5 again. The polymer particles appear in lighter gray and the metal nanoparticles in darker gray on the surface of the polymer particles.

Examples 137 and 138 7.5 parts of the product of Example 3 having a solids content of 50 g / l were heated to 45 ° C. 5 parts of a solution of potassium tetrachloroplatinate (200 g / l) were added in one portion. Subsequently, 4.1 parts of a solution of formaldehyde in water (33.4 g / l) were added. The reaction mixture was stirred for 4 h, during which the solution turned black (Example 99). The TEM analysis shows the presence of metal nanoparticles. In a further batch (Example 100), a sodium borohydride solution in 4 portions was added. The results did not differ. A TEM image of the product obtained is shown in FIG.

Examples 139 to 145 x parts of a residual solution of potassium chloroplatinate and 7.5 ml of an aqueous solution of the reaction product of Example 14 were placed in a reactor. The mixture was stirred at 500 rpm and heated to the reaction temperature of 80 ⁰ C. Subsequently, a stoichiometric amount, based on the metal content, of diethanolamine (166.6 g / l) was added all at once. The reaction mixture was left at 80 ^° C. for 24 hours and stirred at 300 rpm for 5 minutes each hour. Finally, it was cooled to room temperature. Then, x parts of potassium chloropaladate were added. The mixture was stirred at 500 rpm and heated to the reaction temperature of 70 ° C. Subsequently, a stoichiometric amount based on the metal content of 5-pentenoic acid (83.4 g / l) was added at once. The resulting mixture was left at 70 ^° C. for 24 hours and stirred at 300 rpm for 5 minutes each hour. Finally, it was cooled to room temperature.

A TEM image of the product obtained is shown in FIG. 7.

B07 / 1023PC Table 4 summarizes the batch sizes and results of the TEM analysis.

Table 4

Examples 146 to 151

2.5 ml of a solution of tetraammineplatinum (II) nitrate (4.73% by weight of Pt) and 0.48 ml of polymer which has been diluted to a concentration of 10% by weight with demineralized water are placed in a Submitted reactor. The mixture is stirred at 500 rpm and heated to the reaction temperature of 85 ° C. Subsequently, 1, 19 ml of pentenoic acid (at a concentration of 103.3 g / l) added at once. The reaction mixture is left at 85 ° C. for 24 hours, stirring at 300 rpm for 5 minutes each hour. Finally, it is cooled to room temperature. The noble metal particles thus produced have diameters of 1 to 10 nm and a high crystallinity.

Table 5

Examples 152 to 156

0.1214 g of platinum acetylacetonate (98% pure) and 0.1070 g of palladium acetate (98% strength) are dissolved overnight in 7.54 g of diethylene glycol (99% pure). The solution is heated in a 50 ml flask together with another 10 g of diethylene glycol at 30 ⁰ C. After 1 hour

B07 / 1023PC Polymer A is added and then heated to 80 ⁰ C for 2 hours. After cooling to room temperature, the particle size distribution is determined with dynamic light scattering. The results are summarized in Table 6.

Table 6

Claims

claims

1. Metal nanoparticles stabilized with derivatized polyethylenimines or polyvinylamines.

2. Metal nanoparticles according to claim 1, characterized in that the polyethylenimines and polyvinylamines are selected from the group consisting of

A homopolymers of ethyleneimine (aziridine);

B graft polymers of polyamidoamines with ethyleneimine;

C graft polymers of polyvinylamines with ethyleneimine;

D polymers of higher homologs of ethyleneimine;

E at least partially saponified N-vinylcarboxamide homo polymers;

F at least partially saponified N-vinylcarboxamide copolymers,

3. Metal nanoparticles according to claim 1 or 2, characterized in that the polyalkyleneimines and polyvinylamines are derivatized at the nitrogen atoms by

(1) reaction with alpha, beta-unsaturated carbonyl compounds by Michael addition;

(2) reaction with organic or inorganic halides, alkyl trifluoroacetates, alkyl (bromo) toluenesulfonates and / or alkylphenolates;

(3) reaction with dialdehydes and / or diketones;

(4) reaction with epoxides, D / epoxides, halohydrin ethers and / or bishobiliohydrin ethers;

(5) reaction with alkylene carbonates or bischloroformates;

(6) reaction with polyalkylene glycol ethers;

(7) reaction with carboxylic acids or carboxylic acid esters by amidation reaction; B07 / 1023PC (8) reaction with isocyanates and diisocyanates;

(9) reaction with formaldehyde and cyanide salts in a Strecker reaction;

(10) Reaction with formaldehyde and further reaction of the formed imine with further components by Strecker reaction, Mannich reaction or Eschweiler-Clarke reaction, carboxymethylation or phosphono methylation.

4. Metal nanoparticles according to one of claims 1 to 3, characterized in that the metal is selected from the group consisting of copper, silver, gold, palladium, nickel, platinum, rhodium, iron, bismuth, iridium, ruthenium and rhenium.

5. A process for the preparation of metal nanoparticles according to any one of claims 1 to 4, wherein a metal salt solution is reduced in the presence of the derivatized polyethylene imines or polyvinylamines with a reducing agent.

A method according to claim 5, characterized in that metal salt solutions of two or more different metals are reduced simultaneously or sequentially, whereby metal nanoparticles of two or more different metals are obtained.

7. The method according to claim 5 or 6, characterized in that the reducing agent is selected from formic acid, formaldehyde, diethanolamine, 5-pentenoic acid, hydrazine, oxalic acid, sodium borohydride, ethanol, methanol, ethylene glycol and diethylene glycol.

8. The method according to any one of claims 5 to 7, characterized in that the metal salt is selected from the salts of silver, copper, gold, nickel, palladium, platinum, cobalt, iron, rhodium, iridium, zinc, ruthenium and osmium.

9. The method according to any one of claims 5 to 7, characterized in that SiIber is used in the form of silver oxide, silver acetate and / or silver nitrate.

10. The method according to any one of claims 5 to 9, characterized in that palladium in the form of Alkalitetrachloropalladat, palladium (II) nitrate, Tetraaminpalla- dium (II) nitrate and / or palladium (II) acetate is used.

1 1. The method according to any one of claims 5 to 10, characterized in that rhodium in the form of hexachlororhodium (III) acid, rhodium (III) acetate, rhodium (III) oxyhydrate, chlorotris (triphenylphosphine) rhodium (l) and / or acetylacetonato (cyclooctadiene) rhodium (I).

12. The method according to any one of claims 5 to 10, characterized in that platinum in the form of Alkalitetrachloroplatinat, tetraamineplatinum (II) nitrate, hexachloroplatinic acid and / or platinum (II) acetate is used.

13. The method according to any one of claims 5 to 12, characterized in that water is used as the solvent.

14. The method according to any one of claims 5 to 12, characterized in that a polyhydric alcohol is used as the solvent.