METHOD FOR CONTINUOUSLY PREPARING GRAPHENE HEAT-CONDUCTING FILMS

Bucun ZHOU

Patent

Atlas literature

Patent

US 10,961,124

METHOD FOR CONTINUOUSLY PREPARING GRAPHENE HEAT-CONDUCTING FILMS

Bucun ZHOU

Claims

Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.

1 independent · 18 dependent

1
Independentgraphite oxidegraphene oxide powderthermally conductive graphene film
A method for continuously preparing thermally conductive graphene ﬁlms, comprising: 1) processin g a g raphite oxide containing 40 to 60 wt % of moisture into strips via a screw extruder, and then cutting into pellets to obtain graphite oxide particles; 2) stripping the graphite oxide particles of the step 1) at a high temperature to prepare graphene oxide powder; 3) dispersing the g raphene oxide powder of the step 2) in a solvent to form a homogeneous graphene oxide slurry, wherein the graphene oxide slurry has a viscosity of 20000-100000 mPa.s and a ﬁneness of less than 30 pm; 4) defoaming the dispersed graphene oxide slurry of the step 3) under vacuum; 5) coating the defoamed graphene oxide slurry of the step 4) on a substrate to form a graphene oxide ﬁlm with a certain thickness, drying the graphene oxide ﬁlm to remove the solvent, and then continuously winding to form coils; 6) stripping the graphene oxide ﬁlm from the substrate of the coils of the step 5) via a stripping device, and then cutting the edges of the graphene oxide ﬁlm by a trimming device to form continuous coils of graphene oxide ﬁlm; 7) performing heat treatment on the continuous coils of graphene oxide prepared in the step 6) at the temperature of 150 0 C-500 ° C, thereby realizing preliminary reduction of the graphene oxide ﬁlm; 8) subjecting the preliminarily reduced graphene oxide ﬁlm of the step 7) to the temperature of 2200 to 2800 0 C for graphitization to obtain a graphitized graphene ﬁlm; and 9) rolling the graphitized graphene ﬁlm of the step 8) to increase the density to obtain the thermally conduct i ve graphene ﬁlms, wherein the pressure of the rolling ranges from 10 to 30 MPa.
1. 2
  Dependent← claim 1thermally conductive graphene film
  The method according to claim 1, further comprising transferring and sticking the rolled graphene ﬁlm of the step 9) onto the protective ﬁlms to form the ﬁnal product.
2. 3
  Dependent← claim 1graphite oxide
  The method according to claim 1, wherein in the step 1), the graphite oxide particles have a particle size of I to 5 mm.
3. 4
  Dependent← claim 1graphite oxide
  The method according to claim 1, wherein in the step 2), the stripping of the graphene oxide particles is completed in a high-temperature furnace, and the stripping process is protected by nitrogen or argon g as.
4. 5
  Dependent← claim 1graphite oxide
  The method according to claim 1, wherein in the step 2), the temperature of the stripping ranges from 800 to 1500 0 C.
5. 6
  Dependent← claim 1graphene oxide powder
  The method according to claim 1, wherein in the step 2), the graphene oxide powder has a sheet size of 2 to 10 m, and a number of sheet of 1 to 8.
6. 7
  Dependent← claim 1graphene oxide powder
  The method according to claim 1, wherein in the step 3), the graphene oxide powder obtained in the step 2) is dispersed in the solvent through a high-speed disperser.
7. 9
  Dependent← claim 1solvent
  The method according to claim 1, wherein in the step 3), the solvent is selected from the group consisting of ethanol, water, NMP, DMF, furan, tetrahydrofuran or any combination thereof.
8. 10
  Dependent← claim 1graphene oxide powder
  The method according to claim 1, wherein in the step 3), the concentration of the graphene oxide in the graphene oxide slurry is 3 to 20 wt %.
9. 11
  Dependent← claim 1graphene oxide powder
  The method according to claim 1, wherein in the step 4), the defoaming is completed by a defoaming machine, and in the defoamed graphene oxide slurry, there is no bubble larger than 0.2 mm and the content of bubble smaller than 0.2 mm is less than 0.02 ml/L.
10. 12
  Dependent← claim 1
  The method according to claim 1, wherein in the step 5), the coating is performed by blade coating or extrusion coating.
11. 13
  Dependent← claim 1
  The method according to claim 1, wherein in the step 5), the substrate has a thickness of 0.8-3mm and is selected from the group consisting of a steel strip, PET, a stainless steel mesh of 500-2000 mesh or a nylon mesh of 500-1000 mesh.
12. 14
  Dependent← claim 1
  The method according to claim 1, wherein in the step 5), the drying is performed in an oven of a coater and temperature of the drying is 70-150 0 C.
13. 15
  Dependent← claim 1
  The method according to claim 1, wherein in the step 7), the heat treatment is performed in a hot air oven, comprising placing the continuous coils of graphene oxide prepared in the step 6) in the hot air oven heated from room temperature to 150 0 C-500 0 C.
14. 17
  Dependent← claim 1
  The method according to claim 1, wherein in the step 8), the graphitization is completed in a high-temperature induction heating furnace, comprising placing the preliminarily reduced graphene oxide of the step 7) in the high-temperature induction heating furnace heated from room temperature to 2200- 2800 0 C for graphitization.
15. 19
  Dependent← claim 1thermally conductive graphene film
  A thermally conductive graphene ﬁlm prepared by the method of claim 1, wherein the thermally conductive graphene ﬁlm has a density of 0.015 to 2.21 g/cm 3; a thickness of 8 to 1000 m; a thermal conductivity of 800 to 1900 W/m-K; an electromagnetic shielding eﬀectiveness of 60-90dB under the electromagnetic frequency of 30M-3GHz; a conductivity of 5-20 x 1 0 5 S/m; a tensile strength of 20-80 MPa and the thermally conductive graphene ﬁlm

Materials

Materials described outside the worked examples.

graphite oxide

Precursor

graphene oxide powder

Intermediate

Process steps

Additional fabrication and treatment steps described in the patent.

Extrusion And Pelletizing

Step 1

Process details

equipment:screw extruder

particle size mm:1-5

temperature c max:

Reported properties

Performance values and ranges asserted in the specification or claims.

Property	Value	Material
Density	0.015–2.21 g/cm3	thermally conductive graphene film
Thickness	8–1000 um

Why these are connected

Related documents with shared materials, methods, properties, or citations.

METHOD FOR CONTINUOUSLY PREPARING GRAPHENE HEAT-CONDUCTING FILMS | Matter42 Literature