Graphene nanodispersion and method for preparing same

Patent metadata

Field	Value
Publication number	US-10030155-B2
Application number	US-201314400877-A
Country	US
Kind code	B2
Filing date	May 14, 2013
Priority date	May 14, 2012
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

An ionic liquid can disperse graphene at a high concentration. The ionic liquid can be represented by general formula (1):

in which R 1 and R 5 may be the same or different and each independently represents a substituted or unsubstituted C1-7 linear or branched alkyl group; R 2 is represented by formula (2):

in which R 6 and R 7 may be the same or different and each independently represents a C1-4 linear or branched alkylene group, and m represents an integer of 1-5; R 3 and R 4 may be the same or different and each independently represent a hydrogen atom, substituted or unsubstituted C1-4 linear or branched alkyl group; X − represents a counter ion; and n represents 0-30.

First claim

What is claimed is:

1. An ionic liquid represented by the following general formula (1):

wherein R 1 and R 5 may be the same or different and each independently represent a substituted or unsubstituted C 1-7 linear or branched alkyl group,
R 2 is represented by the following formula (2):

wherein R 6 and R 7 may be the same or different and each independently represent a C 1-4 linear or branched alkylene group, m represents an integer of 2 or 3,
R 3 and R 4 may be the same or different and each independently represent a hydrogen atom, substituted or unsubstituted C 1-4 linear or branched alkyl group,
X 31 represents a counter ion,
n represents 1-30.

2. The ionic liquid according to claim 1 , wherein R 1 and R 5 are C 1-6 linear alkyls.

3. The ionic liquid according to claim 1 , wherein R 6 and R 7 are both ethylene groups.

4. The ionic liquid according to claim 1 , wherein n is an integer of 1-2.

5. The ionic liquid according to claim 1 , wherein X − is selected from the group consisting of PF 6 − ,(CF 3 SO 2 ) 2 N − , BF 4 − , Cl − , and Br − .

6. An ionic liquid mixture comprising the ionic liquid (A) according to claim 1 and butylmethylimidazolium hexafluorophosphate (B) or butylmethylimidazolium bis(trifluoromethanesulfonyl)imide (C).

7. A graphene dispersion comprising graphene and the ionic liquid according to claim 1 or an ionic liquid mixture comprising the ionic liquid (A) according to claim 1 and butylmethylimidazolium hexafluorophosphate (B) or butylmethylimidazolium bis(trifluoromethanesulfonyl)imide (C).

8. A method for preparing a graphene dispersion comprising:
(1) adding graphite to the ionic liquid according to claim 1 or an ionic liquid mixture comprising the ionic liquid (A) according to claim 1 and butylmethylimidazolium hexafluorophosphate (B) or butylmethylimidazolium bis(trifluoromethanesulfonyl)imide (C), and
(2) applying ultrasound or microwaves to the mixture obtained in (1).

9. The method according to claim 8 , further comprising centrifuging the mixture obtained after application of ultrasound or microwaves.

10. The method according to claim 8 , further comprising recovering a liquid layer from the mixture after centrifugation.

Assignees

• Univ Tokyo

Inventors

• Aida Takuzo
• PARK Chiyoung
• RAVI Saisuwan
• Matsumoto Michio

Classifications

• C07D233/60 Primary

  with hydrocarbon radicals, substituted by oxygen or sulfur atoms, attached to ring nitrogen atoms · CPC title

• Y10S428/917

  Electroluminescent · CPC title

• C07D403/14 Primary

  containing three or more hetero rings · CPC title

• C07C311/48

  having nitrogen atoms of sulfonamide groups further bound to another hetero atom · CPC title

• C01B32/184

  Preparation · CPC title