Method of preparing a nanoparticle dispersion of a modified metal oxide
AssigneeCabot Corporation
InventorsDhaval A. Doshi, Zhifeng Li
Life of this patent
Estimating the term…
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.
Claims19
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.
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.
Dependencies are inferred from the claim text.