Surface modified layered double hydroxide

Patent metadata

Field	Value
Publication number	US-11242460-B2
Application number	US-201716461246-A
Country	US
Kind code	B2
Filing date	Nov 15, 2017
Priority date	Nov 15, 2016
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

Surface-modified layered double hydroxides (LDHs) are disclosed, as well as processes by which they are made, and uses of the LDHs in composite materials. The surface-modified LDHs of the invention are more organophilic than their unmodified analogues, which allows the LDHs to be incorporated in a wide variety of materials, wherein the interesting functionality of LDHs may be exploited.

First claim

The invention claimed is:

1. A layered double hydroxide of formula (I) shown below:

wherein
M is at least one charged metal cation;
M′ is at least one charged metal cation different from M;
z is 1 or 2;
y is 3 or 4;
0<x<0.9;
0<b≤10;
0<c≤10;
0<d≤10
X is at least one anion;
n is the charge on anion(s) X;
a is equal to z(1−x)+xy−2;
m ≥ a/n; and
the solvent is an organic solvent capable of hydrogen-bonding to water; and
the modifier is an organic moiety capable of covalent or ionic association with at least one surface of the layered double hydroxide, and which modifies the surface properties of the layered double hydroxide;
and wherein the layered double hydroxide has a tap density of less than 0.35 g/mL.

2. The layered double hydroxide of claim 1 , wherein the modifier is an organic moiety comprising at least 5 carbon atoms and at least one functional group that is capable of covalent or ionic association with at least one surface of the layered double hydroxide.

3. The layered double hydroxide of claim 1 , wherein the modifier increases the lipophilicity of the layered double hydroxide.

4. The layered double hydroxide of claim 3 , wherein the modifier is an organosilane or a surfactant.

5. The layered double hydroxide of claim 4 , wherein the organosilane has a structure according to formula (II) shown below

wherein
q is 1, 2 or 3;
each R 1 is independently hydrogen or an organofunctional group;
each Y is independently absent, or is a straight or branched organic linker; and
each R 2 is independently hydrogen, halo, hydroxy, carboxy, (1-4C)alkyl or a group —OR 3 , wherein R 3 is selected from (1-6C)alkyl, aryl(1-6C)alkyl, heteroaryl(1-6C)alkyl, cycloalkyl(1-6C)alkyl, heterocyclyl(1-6C)alkyl and (1-6C)alkoxy(l-4C)alkyl.

6. The layered double hydroxide of claim 5 , wherein the organofunctional group is selected from acrylate, methacrylate, mercapto, aldehyde, amino, azido, carboxylate, phosphonate, sulfonate, epoxy, glycidyloxy, ester, halogen, hydroxyl, isocyanate, phosphine, phosphonate, alkenyl, aryl, cycloalkyl, heteroaryl and heterocyclyl.

7. The layered double hydroxide of claim 4 , wherein the surfactant is a non-ionic, cationic, anionic or amphoteric surfactant.

8. The layered double hydroxide of claim 4 , wherein the surfactant is a (4-22C)fatty acid or a salt thereof.

9. The layered double hydroxide of claim 1 , wherein d has a value according to the expression 1≤d≤2.

10. The layered double hydroxide of claim 1 , wherein z is 2, M is Mg, Zn, Fe, Ca, Sn, Ni, Cu, Co, Mn or Cd or a mixture of two or more of these, or when z is 1, M is Li.

11. The layered double hydroxide of claim 1 , wherein y is 3, M′ is Al, Ga, Y, In, Fe, Co, Ni, Mn, Cr, Ti, V, La or a mixture thereof, or when y is 4, M′ is Sn, Ti or Zr or a mixture thereof.

12. The layered double hydroxide of claim 1 , wherein M′ is Al.

13. The layered double hydroxide of claim 1 , wherein the layered double hydroxide of formula (I) is a Zn/Al, Mg/Al, Mg,Zn/Al, Mg/Al,Sn, Ca/Al, Ni/Ti or Cu/Al layered double hydroxide.

14. The layered double hydroxide of claim 1 , wherein X is an anion selected from at least one of halide, inorganic oxyanion, or an organic anion.

15. The layered double hydroxide of claim 14 , wherein the inorganic oxyanion is carbonate, bicarbonate, hydrogenphosphate, dihydrogenphosphate, nitrite, borate, nitrate, sulphate or phosphate or a mixture of two or more thereof.

16. The layered double hydroxide of claim 1 , wherein X is carbonate.

17. The layered double hydroxide of claim 1 , wherein M is Mg, M′ is Al and X is carbonate.

18. The layered double hydroxide of claim 1 , wherein the solvent is selected from the group consisting of acetone, acetonitrile, dimethylformamide, dimethyl sulphoxide, dioxane, ethanol, methanol, n-propanol, isopropanol, tetrahydrofuran, ethyl acetate, n-butanol, sec-butanol, n-pentanol, n-hexanol, cyclohexanol, diethyl ether, diisopropyl ether, di-n-butyl ether, methyl tert-butyl ether (MTBE), tert-amyl methyl ether, cyclopentyl methyl ether, cyclohexanone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), methyl isoamyl ketone, methyl n-amyl ketone, furfural, methyl formate, methyl acetate, isopropyl acetate, n-propyl acetate, isobutyl acetate, n-butyl acetate, n-amyl acetate, n-hexyl acetate, methyl amyl acetate, methoxypropyl acetate, 2-ethoxyethyl acetate, nitromethane, and a mixture of two or more thereof.

19. The layered double hydroxide of claim 1 , wherein the solvent is selected from the group consisting of acetone, ethanol, ethyl acetate, and a mixture of two or more thereof.

20. The layered double hydroxide of claim 1 , wherein the layered double hydroxide also has a loose bulk density of less than 0.35 g/mL.

21. The layered double hydroxide of claim 1 , wherein the layered double hydroxide also has a BET pore volume of at least 0.3 cc/g.

22. A process for the preparation of a layered double hydroxide of formula (I), the process comprising the steps of:
a) providing a layered double hydroxide of formula (Ia):

where M, M′, z, y, x, b, c, X, m, and the solvent are as specified in claim 1 ;
b) providing a modifier being an organic moiety of covalent or ionic association with at least one surface of the layered double hydroxide, and which is capable of modifying the surface properties of the layered double hydroxide; and
c) contacting the layered double hydroxide of formula (Ia) provided in step a) with the modifier provided in step b), wherein the layered double hydroxide has a tap density of less than 3.5 g/mL.

23. A composite material comprising the layered double hydroxide as claimed in claim 1 dispersed throughout a polymer.

Assignees

• Scg Chemicals Co Ltd

Inventors

• O'Hare Dermot
• Buffet Jean-Charles
• Chen Chunping
• Ruengkajorn Kanittika
• Wongariyakawee Anchalee

Classifications

• C09C1/407 Primary

  Aluminium oxides or hydroxides · CPC title

• C01F7/784

  Layered double hydroxide, e.g. comprising nitrate, sulfate or carbonate ions as intercalating anions · CPC title

• C09C1/40 Primary

  Compounds of aluminium {(C09C1/0009, C09C1/0015, C09C1/0078, C09C1/32 take precedence)} · CPC title

• C08K3/013

  Fillers, pigments or reinforcing additives · CPC title

• C01P2006/10

  Solid density · CPC title