Nano-composite

Patent metadata

Field	Value
Publication number	US-9267029-B2
Application number	US-201113575755-A
Country	US
Kind code	B2
Filing date	Jan 27, 2011
Priority date	Jan 28, 2010
Publication date	Feb 23, 2016
Grant date	Feb 23, 2016

Abstract

There is provided a method of making a nano-composite having individual nano-sized silica particles dispersed in a polymer matrix, the method comprises the step of curing a substantially homogeneous mixture of surface-functionalized nano-sized silica particles, a polymerizable resin and a curing agent, wherein said substantially homogeneous mixture is substantially free of alcoholic solvent to form the nano-composite.

First claim

The invention claimed is:

1. A method of making a nano-composite having individual nano-sized silica particles dispersed in a polymer matrix which comprises steps of:
providing a substantially homogeneous mixture which comprises silica precursors; a polymerizable resin; a coupling agent having functional groups; a curing agent and an alkaline catalyst; and
hydrolyzing and condensing said silica precursors in said substantially homogeneous mixture, wherein the alkaline catalyst is selected to initiate hydrolysis and condensation of the silica precursors to form the silica particles while simultaneously functionalizing the formed silica particles with the functional groups of the coupling agent, said hydrolyzing, condensing and functionalizing being undertaken under shear conditions and in the absence of an alcoholic solvent in said homogeneous mixture to form individual nano-sized silica particles dispersed in said polymerizable resin.

2. The method of claim 1 , further comprising the step of curing the substantially homogeneous mixture containing the nano-sized silica particles to form a solidified nano-composite.

3. The method of claim 1 , wherein said silica particles are functionalized with amine groups or epoxide groups.

4. The method of claim 1 , wherein said coupling agent is an organo-silane coupling agent having amine functional groups and alkoxy functional groups.

5. The method of claim 4 , further comprising the step of hydrolyzing said coupling agent to form a hydrolyzed organo-silane coupling agent having amine functional groups and hydroxyl functional groups.

6. The method of claim 1 , wherein the silica precursors comprise silicon alkoxides of the following formula Si(OR) n , in which R is an C 1-6 alkyl group and n is 4.

7. The method of claim 6 , wherein said silicon alkoxides hydrolyze to form silicon hydroxides.

8. The method of claim 7 , wherein said silicon hydroxides condense to form hydrolyzed silica particles.

9. The method of claim 8 , wherein the functional groups of the coupling agent condense with the hydroxyl groups on the surface of the hydrolyzed silica particles.

10. The method of claim 1 , wherein said shear conditions are generated by agitating said substantially homogeneous mixture.

11. The method of claim 1 , wherein the polymerizable resin comprises a thermosetting polymer.

12. The method of claim 11 , wherein the thermosetting polymer comprises an epoxy polymer.

13. The method of claim 12 , wherein the epoxy polymer comprises a plurality of epoxide groups.

14. The method of claim 1 , wherein the nano-sized silica particles are in an amount of from about 0.1 to about 10% by weight of the nano-composite.

15. The method of claim 1 , wherein the nano-sized silica particles have an average particle size ranging from about 10 to about 500 nm.

16. The method of claim 1 , wherein the alkaline catalyst is selected from the group consisting of ammonia, ammonium hydroxide solution and an alkylamine.

17. A nano-composite comprising nano-sized silica particles dispersed in a polymer matrix made according to the method of claim 1 , wherein the nano-sized silica particles are substantially elongate.

18. The nano-composite as claimed in claim 17 , wherein the aspect ratio of the nano-sized silica particles is greater than about 1.

19. The nano-composite as claimed in claim 17 , wherein the nano-sized silica particles are present in the nano-composite in an amount less than about 6% by weight of the nano-composite.

Assignees

• Phonthammachai Nopphawan
• He Chaobin
• Li Xu
• Chia Hong Ling
• Agency Science Tech & Res

Inventors

• Phonthammachai Nopphawan
• He Chaobin
• Li Xu
• Chia Hong Ling

Classifications

• C01P2004/62

  Submicrometer sized, i.e. from 0.1-1 micrometer · CPC title

• C08K3/36

  Silica · CPC title

• C08L63/00 Primary

  Compositions of epoxy resins; Compositions of derivatives of epoxy resins · CPC title

• C08K5/544

  containing nitrogen · CPC title

• B82Y30/00

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