Nanocomposite containing hollow silica spheres functionalized with azole silanes

Patent metadata

Field	Value
Publication number	US-10947255-B2
Application number	US-201916448469-A
Country	US
Kind code	B2
Filing date	Jun 21, 2019
Priority date	Jun 21, 2019
Publication date	Mar 16, 2021
Grant date	Mar 16, 2021

Abstract

A nanocomposite containing azole modified hollow silica spheres. In particular, the nanocomposite involves a silanization reaction product of an azole-functionalized silane linker and hollow silica spheres. The azole-functionalized silane linker is produced via a ring-opening reaction a silane coupling agent having an epoxide group and an azole compound. A method of making the nanocomposite is also specified.

First claim

The invention claimed is:

1. A nanocomposite, comprising a silanization reaction product of:
a hollow silica sphere comprising a silica-containing shell surrounding a core; and
an azole-functionalized silane linker,
wherein:
the silica-containing shell has a higher density of silica compared to the core;
the hollow silica sphere has an average diameter of 300-900 nm;
the azole-functionalized silane linker is a ring-opening reaction product of:
a coupling agent of formula (I)

 and
an azole moiety selected from the group consisting of 1H-1,2,4-triazole, 3-amino-1,2,4-triazole, and 5-aminotetrazole,
wherein:
R 1 and R 2 are independently an optionally substituted C 1 -C 6 alkoxy;
R 3 is selected from the group consisting of an optionally substituted C 1 -C 6 alkoxy, an optionally substituted alkyl, and an optionally substituted cycloalkyl;
m is an integer in a range of 2-10; and
n is an integer in a range of 1-6, and

a weight ratio of the hollow silica sphere to the azole-functionalized silane linker is in a range of 2:1 to 50:1.

2. The nanocomposite of claim 1 , wherein R 1 and R 2 are independently a methoxy, or an ethoxy.

3. The nanocomposite of claim 1 , wherein R 3 is selected from the group consisting of a methoxy, an ethoxy, a methyl, and an ethyl.

4. The nanocomposite of claim 1 , wherein m is 3.

5. The nanocomposite of claim 1 , wherein n is 1.

6. The nanocomposite of claim 1 , wherein the coupling agent of formula (I) is (3-glycidyloxypropyl)-trimethoxysilane, (3-glycidyloxypropyl)-triethoxysilane, or both.

7. The nanocomposite of claim 1 , wherein a molar ratio of the coupling agent of formula (I) to the azole moiety is in a range of 1:2 to 2:1.

8. The nanocomposite of claim 1 , wherein the hollow silica sphere comprises at least 85 wt % of silica relative to a total weight of the hollow silica sphere.

9. The nanocomposite of claim 1 , wherein the silica-containing shell has a thickness in a range of 100-250 nm.

10. The nanocomposite of claim 1 , wherein the core has a diameter in a range of 100-400 nm.

11. A method of preparing the nanocomposite of claim 1 , the method comprising:
mixing a hydrolyzable aryl silane and an acid in an aqueous solution to form a hydrolyzed silane solution;
mixing the hydrolyzed silane solution with a hydroxide base to form a precipitate;
drying the precipitate to form a hollow silica sphere;
reacting a coupling agent of formula (I)

with an azole moiety selected from the group consisting of 1H-1,2,4-triazole, 3-amino-1,2,4-triazole, and 5-aminotetrazole to form an azole-functionalized silane linker;
mixing the hollow silica sphere and the azole-functionalized silane linker to form a mixture; and
heating the mixture thereby forming the nanocomposite,
wherein:
R 1 and R 2 are independently an optionally substituted C 1 -C 6 alkoxy;
R 3 is selected from the group consisting of an optionally substituted C 1 -C 6 alkoxy, an optionally substituted alkyl, and an optionally substituted cycloalkyl;
m is an integer in a range of 2-10;
n is an integer in a range of 1-6; and
a weight ratio of the hollow silica sphere to the azole-functionalized silane linker is in a range of 2:1 to 50:1.

12. The method of claim 11 , wherein the precipitate is dried at a temperature in a range of 50-150° C.

13. The method of claim 11 , wherein the reacting occurs in an alcohol at a temperature in a range of 50-150° C.

14. The method of claim 11 , wherein the mixture has a pH of 9-11.

15. The method of claim 11 , wherein the heating is conducted at a temperature in a range of 40-100° C.

16. The method of claim 11 , wherein the hydrolyzable aryl silane is trimethoxyphenylsilane.

17. The method of claim 11 , wherein the acid is nitric acid, and wherein the hydroxide base is ammonium hydroxide.

18. The method of claim 11 , wherein to the coupling agent of formula (I) is selected from 3-glycidyloxypropyl)trimethoxysilane or (3-glycidyloxypropyl)triethoxysilane.

Assignees

• Univ Imam Abdulrahman Bin Faisal

Inventors

• Asiri Sarah Mousa M
• Bozkurt Ayhan

Classifications

• C07F7/10 Primary

  containing nitrogen {having a Si-N linkage} · CPC title

• A61P35/00

  Antineoplastic agents · CPC title

• C08G77/26 Primary

  nitrogen-containing groups · CPC title

• C08G77/14

  containing silicon bound to oxygen-containing groups · CPC title