Single crystal graphene or polycrystalline graphene matrix composite containing carbon-based fillers

Patent metadata

Field	Value
Publication number	US-10808158-B2
Application number	US-201715711477-A
Country	US
Kind code	B2
Filing date	Sep 21, 2017
Priority date	Dec 5, 2012
Publication date	Oct 20, 2020
Grant date	Oct 20, 2020

Abstract

A process for producing a unitary graphene matrix composite, the process comprising: (a) preparing a graphene oxide gel having graphene oxide molecules dispersed in a fluid medium, wherein the graphene oxide gel is optically transparent or translucent; (b) mixing a carbon or graphite filler phase in said graphene oxide gel to form a slurry; (c) dispensing said slurry onto a surface of a supporting substrate or a cavity of a molding tool; (d) partially or completely removing the fluid medium from the slurry to form a composite precursor; and (e) heat-treating the composite precursor to form the unitary graphene composite at a temperature higher than 100° C. This composite exhibits a combination of exceptional thermal conductivity, electrical conductivity, mechanical strength, surface hardness, and scratch resistance.

First claim

We claim:

1. A graphene matrix composite comprising: (a) a polycrystalline graphene matrix material having incomplete grain boundaries, containing closely packed and chemically bonded graphene planes having an inter-graphene plane spacing of 0.335 to 0.40 nm and an oxygen content of 0.001% to 10% by weight; (b) a carbon or graphite filler phase selected from a carbon or graphite fiber, carbon or graphite nanofiber, carbon nanotube, carbon nanorod, mesophase carbon particle, mesocarbon microbead, exfoliated graphite flake with a thickness greater than 100 nm, exfoliated graphite or graphite worm, coke particle, needle coke, carbon black or acetylene black particle, activated carbon particle, or a combination thereof; wherein the filler phase is covalently bonded to the matrix material, and wherein the filler phase has a weight fraction of 0.01% to 99% based on the total composite weight.

2. The graphene matrix composite of claim 1 having a thickness from 10 nm to 200 μm.

3. The graphene matrix composite of claim 1 having a density from 1.5 g/cm 3 to 2.0 g/cm 3 , a porosity from 5% to 20%, or both.

4. The graphene matrix composite of claim 1 having a thermal conductivity from 600 W/mK to 1,750 W/mK.

5. The graphene matrix composite of claim 1 having an electrical conductivity from 2,000 S/cm to 10,000 S/cm.

6. The graphene matrix composite of claim 1 having a tensile strength from 40 to 200 MPa.

7. The graphene matrix composite of claim 1 having a Rockwell surface hardness from 60 to 100.

8. The graphene matrix composite of claim 1 wherein the graphene planes of the matrix material have a crystallographic c-axis having an average miss-orientation angle of less than 10 degrees or wherein the graphene planes of the matrix material are essentially parallel to each other.

9. The graphene matrix composite of claim 1 having graphene crystals from 100 microns to 1 cm in size.

10. The graphene matrix composite of claim 1 wherein the matrix material is a two dimensional or three dimensional network.

11. The graphene matrix composite of claim 1 wherein the filler phase has a particulate, filamentary, or rod-like form.

12. The graphene matrix composite of claim 1 wherein the filler phase is aligned along a direction to create anisotropy.

13. The graphene matrix composite of claim 1 wherein the filler phase is a porous mat, a porous web, a porous preform, a porous paper, a nonwoven fabric, or a woven fabric.

Assignees

• Global Graphene Group Inc

Inventors

• Zhamu Aruna
• Jang Bor Z

Classifications

• B29D7/01

  Films or sheets · CPC title

• B29B13/021

  Heat treatment of powders · CPC title

• H01B1/04

  mainly consisting of carbon-silicon compounds, carbon or silicon · CPC title

• C09K5/14 Primary

  Solid materials, e.g. powdery or granular · CPC title