Method of preparing a nanoparticle dispersion of a modified metal oxide

Patent metadata

Field	Value
Publication number	US-9284419-B2
Application number	US-71250110-A
Country	US
Kind code	B2
Filing date	Feb 25, 2010
Priority date	Aug 31, 2007
Publication date	Mar 15, 2016
Grant date	Mar 15, 2016

Abstract

The present invention relates to a method of preparing polymer compositions comprising modified metal oxides in a polymer wherein a nanoparticle dispersion of a metal oxide in a non-aqueous solvent is combined with at least one coupling agent to form a nanoparticle dispersion of a modified metal oxide in the non-aqueous solvent. The nanoparticle dispersion is then combined with a polymer followed by the removal of the non-aqueous solvent or, alternatively, combined with a monomer, which is polymerized to form the polymer and removal of the solvent, in any order. Also disclosed are polymer compositions prepared by this method.

First claim

What is claimed is:

1. A method of preparing a transparent polymer composition comprising a modified nanoparticle dispersed in a polymer, wherein the method comprises the steps of:
i. hydrolyzing a metal oxide precursor in a water miscible non-aqueous solvent to form a non-aqueous nanoparticle dispersion of a metal oxide in a water miscible non-aqueous solvent, the nanoparticles having an average particle size of less than 50 nm;
ii. combining the non-aqueous nanoparticle dispersion and at least one coupling agent to form a nanoparticle dispersion of a modified metal oxide in the water miscible non-aqueous solvent, wherein the metal oxide and the coupling agent are combined in a weight ratio of between about 25:1 and about 100:1 metal oxide to coupling agent;
iii. combining the nanoparticle dispersion of the modified metal oxide in the water miscible non-aqueous solvent and at least one polymer; and
iv. removing the water miscible non-aqueous solvent to form the transparent polymer composition, wherein the coupling agent has a refractive index of greater than or equal to 1.48 and wherein the polymer composition has an absorbance of less than or equal to 6 at 400 nm, an absorbance of less than or equal to 3 at 450 nm, and an absorbance of less than or equal to 1 at 650 nm.

2. The method of claim 1 , wherein the polymer is soluble in the water miscible non-aqueous solvent.

3. The method of claim 1 , wherein the polymer is dissolved in an organic solvent to form a polymer solution that is soluble in the water miscible non-aqueous solvent.

4. The method of claim 1 , wherein the coupling agent has a refractive index of greater than or equal to 1.6.

5. The method of claim 1 , wherein the metal oxide and coupling agent are combined in a weight ratio of between about 50:1 and about 100:1 metal oxide to coupling agent.

6. The method of claim 1 , wherein the metal oxide has a refractive index of greater than or equal to 1.8.

7. The method of claim 1 , wherein the metal oxide is a titanate.

8. The method of claim 1 , wherein the metal oxide is rutile titania.

9. The method of claim 1 , wherein the metal oxide is barium titanate.

10. The method of claim 1 , wherein the metal oxide has a particle size of between about 2 and about 15 nm in the nanoparticle dispersion in the water miscible non-aqueous solvent.

11. The method of claim 1 , wherein the modified metal oxide has a particle size of between about 2 and about 15 nm in the nanoparticle dispersion in the water miscible non-aqueous solvent.

12. The method of claim 1 , wherein the coupling agent comprises at least one group capable of reacting with the metal oxide and at least one group capable of interacting with the water miscible non-aqueous solvent, the polymer, or both.

13. The method of claim 12 , wherein the group capable of reacting with the metal oxide comprises at least one metal-containing group, at least one carboxylic acid group, at least one sulfinic acid group, at least one sulfonic acid group, at least one thiol group or at least one phosphorous-containing group.

14. The method of claim 12 , wherein the group capable of reacting with the metal oxide comprises at least one phosphonic acid group.

15. The method of claim 12 , wherein the group capable of interacting with the polymer comprises at least one alkylene oxide group.

16. The method of claim 15 , wherein the group capable of interacting with the polymer comprises a polyalkylene oxide group having the formula —(O-ALK1) x -(O-ALK2) y -(O-ALK3) z -, wherein ALK1, ALK2, and ALK3 are linear or branched C1-C8 alkylene groups, x is 1 to 10, and y and z are 0 to 10.

17. The method of claim 1 , wherein the polymer composition has a refractive index of greater than or equal to 1.5, an absorbance of less than or equal to 6 at 400 nm, an absorbance of less than or equal to 3 at 450 nm and an absorbance of less than or equal to 1 at 650 nm.

18. The method of claim 17 , wherein the polymer composition has a refractive index of greater than or equal to 1.7.

19. A method of preparing a polymer composition comprising a modified nanoparticle dispersed in a polymer, wherein the method comprises the steps of:
i. hydrolyzing a metal oxide precursor in a water miscible non-aqueous solvent to form a non-aqueous nanoparticle dispersion of a metal oxide in a water miscible non-aqueous solvent, the nanoparticles having an average particle size of less than 50 nm;
ii. combining the non-aqueous nanoparticle dispersion of a metal oxide and at least one coupling agent to form a nanoparticle dispersion of a modified metal oxide in the water miscible non-aqueous solvent, wherein the metal oxide and the coupling agent are combined in a weight ratio of between about 25:1 and about 100:1 metal oxide to coupling agent;
iii. combining the nanoparticle dispersion of the modified metal oxide in the water miscible non-aqueous solvent and at least one polymer to form the polymer composition; and
iv. removing the water miscible non-aqueous solvent, wherein the polymer composition has a refractive index of greater than or equal to 1.5 and is transparent and wherein the polymer composition has an absorbance of less than or equal to 6 at 400 nm, an absorbance of less than or equal to 3 at 450 nm, and an absorbance of less than or equal to 1 at 650 nm.

Assignees

• Doshi Dhaval A
• Li Zhifeng
• Cabot Corp

Inventors

• Doshi Dhaval A
• Li Zhifeng

Classifications

• C08F2/44

  Polymerisation in the presence of compounding ingredients, e.g. plasticisers, dyestuffs, fillers · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• C08F2/06

  Organic solvent · CPC title

• C08J3/28

  Treatment by wave energy or particle radiation · CPC title

• C08J5/005

  Reinforced macromolecular compounds with nanosized materials, e.g. nanoparticles, nanofibres, nanotubes, nanowires, nanorods or nanolayered materials · CPC title