Method of producing nanoparticle suspensions

Patent metadata

Field	Value
Publication number	US-9296685-B2
Application number	US-201113583536-A
Country	US
Kind code	B2
Filing date	Mar 7, 2011
Priority date	Mar 8, 2010
Publication date	Mar 29, 2016
Grant date	Mar 29, 2016

Abstract

Method of producing a nanoparticle suspension with the steps (i) preparation of an emulsion of a disperse polar phase, where the aqueous phase comprises one or more precursor substances forming the nanoparticles, in a continuous organic phase in the presence of an emulsifier stabilizing the emulsion, (ii) conversion of the one or more precursor substances to nanoparticles in the disperse aqueous phase, (iii) breaking of the emulsion and phase separation, where the nanoparticle suspension is obtained as one phase, (iv) separation off of the nanoparticle suspension, (v) optionally isolation of the nanoparticles from the nanoparticle suspension, wherein the emulsifier is selected from compounds of the general formula (I) in which X is O, NH, Y is C(O), NH, R is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 6 to 30 carbon atoms and R 1 is hydrogen or C 1 -C 4 -alkyl, and R 2 is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 1 to 30 carbon atoms, preferably 6 to 30 carbon atoms, R 3 is C 1 -C 4 -alkyl, n is 0 or 1, and the breaking of the emulsion is effected by splitting the emulsifier.

First claim

The invention claimed is:

1. A method of producing a nanoparticle suspension, the method comprising:
(i) converting one or more precursor substances in an emulsion to nanoparticles in a disperse polar phase, wherein the disperse polar phase comprises the one or more precursor substances in a continuous nonpolar phase in the presence of an emulsifier stabilizing the emulsion;
(ii) breaking the emulsion and phase separating the disperse polar phase to obtain at least one nanoparticle suspension as at least one phase, such that the breaking of the emulsion is effected by splitting the emulsifier;
(iii) separating off the nanoparticle suspension; and
(iv) optionally isolating nanoparticles from the nanoparticle suspension,
wherein:
the emulsifier is at least one compound of formula (I):

X is O, NH, or NR 2 ;
Y is C(O), NH, or NR 3 ;
R is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 6 to 30 carbon atoms;
R 1 is hydrogen or C 1 -C 4 -alkyl;
R 2 is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 1 to 30 carbon atoms;
R 3 is C 1 -C 4 -alkyl; and
n is 0 or 1.

2. The method according to claim 1 , wherein the emulsifier is selected from the group consisting of an oxalic acid ester of formula (Ia), an oxamate of formula (Ib), a hydroxycarbamate of formula (Ic), and malonic acid ester of formula (Id):

wherein:
R is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 6 to 30 carbon atoms; and
R 1 is hydrogen or C 1 -C 4 -alkyl.

3. The method according to claim 1 , wherein the splitting of the emulsifier is effected by adding a base to the emulsion.

4. The method according to claim 3 , wherein the emulsifier is an oxalic acid ester of formula (Ia):

5. The method according to claim 1 , wherein the splitting is effected by heating the emulsion to a temperature of from 50 to 200° C.

6. The method according to claim 1 , wherein the nonpolar phase is a solvent selected from the group consisting of an n-alkane, an aromatic hydrocarbon, an ether, a paraffin, a wax, a mineral oil and a vegetable oil.

7. A method for functionalizing nanoparticles, the method comprising:
(i) reacting nanoparticles, in an emulsion of a disperse polar phase, with functionalization reagents in the disperse polar phase, wherein the disperse polar phase comprises the nanoparticles in suspended form in a continuous nonpolar phase in the presence of an emulsifier stabilizing the emulsion, such that the disperse polar phase, the continuous nonpolar phase, or both, comprise one or more functionalization reagents in dissolved form;
(ii) breaking the emulsion and phase separating the disperse polar phase to obtain, at least one nanoparticle suspension as at least one phase, such that the breaking of the emulsion is effected by splitting the emulsifier;
(iii) separating off the nanoparticle suspension; and
(iv) optionally isolating functionalized nanoparticles,
wherein:
the emulsifier is at least one compound of formula (I):

X is 0, NH, or NR 2 ;
Y is C(0), NH, or NR 3 ;
R is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 6 to 30 carbon atoms;
R 1 is hydrogen or C 1 -C 4 -alkyl;
R 2 is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 1 to 30 carbon atoms;
R 3 is C 1 -C 4 -alkyl; and
n is 0 or 1.

8. The method according to claim 7 , wherein the emulsifier is selected from the group consisting of an oxalic acid ester of formula (Ia), an oxamate of formula (Ib), a hydroxycarbamate of formula (Ic), and a malonic acid ester of formula (Id):

wherein:
R is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 6 to 30 carbon atoms; and
R 1 is hydrogen or C 1 -C 4 -alkyl.

9. The method according to claim 7 , wherein the splitting of the emulsifier is carried out by adding a base to the emulsion.

10. The method according to claim 9 , wherein the emulsifier is an oxalic acid ester of formula (Ia):

11. An emulsifier selected from the group consisting of an oxamate of formula (Ib), a hydroxycarbamate of formula (Ic), and a malonic acid ester of formula (Id):

wherein:
R is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 6 to 30 carbon atoms; and
R 1 is hydrogen or C 1 -C 4 -alkyl,
wherein for compound (Ic), R 1 is C 1-4 alkyl .

12. An emulsifier, comprising an oxalic acid ester of formula (Ia):

wherein:
R represents a linear C 10 -, C 14 -, C 16 -C 18 or C 20 -alkyl group; and
R 1 is hydrogen.

13. An emulsifier, consisting of an oxalic acid ester of formula (Ia):

wherein:
R represents a linear C 10 -, C 14 -, C 16 -, C 18 - or C 20 -alkyl group; and
R 1 is hydrogen.

14. The method of claim 1 , wherein R 2 is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 6 to 30 carbon atoms.

15. The method according to claim 2 , wherein the splitting of the emulsifier is effected by adding a base to the emulsion.

16. The method according to claim 15 , wherein the emulsifier is an oxalic acid ester of formula (Ia):

17. The method according to claim 2 , wherein the splitting is effected by heating the emulsion to a temperature of from 50 to 200° C.

18. The method of claim 7 , wherein R 2 is a saturated or a mono- or polyunsaturated, linear or branched hydrocarbon radical having 6 to 30 carbon atoms.

Assignees

• Engel Robert
• Gerlinger Wolfgang
• Braese Stefan
• Muller Thierry
• Belenki Christina
• Schuchmann Heike P
• Gedrat Marion
• Basf Se

Inventors

• Engel Robert
• Gerlinger Wolfgang
• Braese Stefan
• Muller Thierry
• Belenki Christina
• Schuchmann Heike P
• Gedrat Marion

Classifications

• B01F17/0021

  Operations & Transport · mapped topic

• C07C69/38

  Malonic acid esters · CPC title

• C07C69/36

  Oxalic acid esters · CPC title

• C07C233/56

  having carbon atoms of carboxamide groups bound to carbon atoms of carboxyl groups, e.g. oxamides · CPC title

• C07C271/08 Primary

  having oxygen atoms of carbamate groups bound to acyclic carbon atoms · CPC title