Nanodiamond composites and methods for their synthesis

Patent metadata

Field	Value
Publication number	US-2016152791-A1
Application number	US-201514949754-A
Country	US
Kind code	A1
Filing date	Nov 23, 2015
Priority date	Nov 21, 2014
Publication date	Jun 2, 2016
Grant date	—

Abstract

Disclosed herein are nanodiamond composites and methods for their synthesis. In particular, the nanodiamond composites include large-surface-area polymer composites that include a polymer and nanodiamond dispersed and bound therein. The resulting composites having certain properties of diamond (e.g., drug-loading sites with low toxicity) yet are inexpensive and relatively easy to fabricate. Aerogels formed using a polycondensation polymer are particularly described herein, although many polymer systems are compatible. Synthesis of the nanodiamond composites is achieved by polymerizing a mixture of nanodiamond and a polymer precursor.

First claim

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1 . A method of producing a nanodiamond composite, comprising:
forming a gel by mixing oxidized diamond nanocrystals, a solvent capable of dispersing the oxidized diamond nanocrystals, and a polymer precursor system configured to form a polymer when polymerized, wherein the gel comprises the solvent and the polymer having the oxidized diamond nanocrystals dispersed and bound therein.

2 . The method of claim 1 , wherein the nanodiamond composite is a nanodiamond solid formed by the additional step of drying the gel to remove the solvent.

3 . The method of claim 2 , further comprising a step of washing the gel prior to drying the gel.

4 . The method of claim 2 , wherein the step of drying the gel comprises supercritically drying the gel to provide a nanodiamond aerogel that is a high-surface-area nanodiamond composite.

5 . The method of claim 4 , wherein supercritically drying the gel comprises supercritical point drying.

6 . The method of claim 1 , further comprising the steps of:
providing a template onto which the step of forming the gel is performed, to provide a templated gel; and drying the templated gel to remove the solvent and provide a templated nanodiamond composite.

7 . The method of claim 6 , wherein the template comprises a plurality of nanospheres.

8 . The method of claim 6 , further comprising a step of removing the template from the templated nanodiamond composite to provide a high-surface-area nanodiamond composite.

9 . The method of claim 1 , wherein the oxidized diamond nanocrystals are oxidized detonation nanodiamond (DND) nanocrystals.

10 . The method of claim 9 , wherein the oxidized DND nanocrystals are formed by thermally oxidizing DND nanocrystals in an oxygen-containing atmosphere.

11 . The method of claim 10 , wherein the oxygen-containing atmosphere is air.

12 . The method of claim 10 , wherein the thermal oxidation is for a temperature and time sufficient to remove amorphous carbon soot and generate chemically reactive surface-oxygen functional groups on the DND nanocrystals, thus producing oxidized DND nanocrystals.

13 . The method of claim 9 , wherein the DND nanocrystals have a smallest dimension of about 1 nm to about 10 nm.

14 . The method of claim 1 , wherein the oxidized diamond nanocrystals are oxidized plasma-generated diamond nanocrystals.

15 . The method of claim 1 , wherein the solvent is a polar solvent selected from the group consisting of acetonitrile and water.

16 . The method of claim 1 , wherein the polymer precursor system is a polycondensation precursor system comprising a first polycondensation precursor and a second polycondensation precursor configured to form a polycondensation polymer when reacted with the first polycondensation precursor.

17 . The method of claim 16 , wherein the first polycondensation precursor is a diol and the second polycondensation precursor comprises an aldehyde.

18 . The method of claim 17 , wherein the diol resorcinol and the aldehyde is formaldehyde.

19 . The method of claim 16 , wherein the step of forming the gel comprises mixing a catalyst configured to facilitate formation of the polycondensation polymer with the polycondensation precursor system.

20 . The method of claim 19 , wherein the catalyst is hydrochloric acid.

21 . The method of claim 1 , wherein the polymer precursor system is a radical polymerization precursor system comprising a radical polymer precursor and an initiator configured to polymerize the radical polymer precursor.

22 . The method of claim 1 , wherein mixing comprises sonication.

23 . The method of claim 1 , wherein the mixing occurs at a temperature that does not exceed 55° C.

24 . A nanodiamond composite formed by the method of claim 1 .

25 . A nanodiamond aerogel comprising a polycondensation polymer aerogel having oxidized DND nanocrystals comprise twinning planes.

26 . The nanodiamond aerogel of claim 25 , wherein the surface area is about 350 m 2 /g to about 1000 m 2 /g.

27 . The nanodiamond aerogel of claim 25 , wherein the bulk density is about 150 mg/cm 3 to about 500 mg/cm 3 .

28 . The nanodiamond aerogel of claim 25 , further comprising one or more heavy metals.

29 . The nanodiamond aerogel of claim 28 , wherein the one or more heavy metals comprises 100 ppm or greater of iron.

30 . The nanodiamond aerogel of claim 25 , wherein the oxidized DND nanocrystals are 1% to 25%, by weight, of the nanodiamond aerogel.

Assignees

• Univ Washington

Inventors

• Pauzauskie Peter J
• Lim Matthew B
• Manandhar Sandeep

Classifications

• C08J9/008 Primary

  Nanoparticles · CPC title

• C08K2003/0856

  Iron · CPC title

• C08J2361/12

  with polyhydric phenols · CPC title

• C08J9/28

  by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum · CPC title

• C08K3/08 Primary

  Metals · CPC title