Resin-impregnated flexible graphite articles
View Patent ↗Composites are prepared from resin-impregnated flexible graphite materials. Impregnated materials are compressed and cured at elevated temperature and pressure to form structures suitable for uses such as electronic thermal management (ETM) devices, supercapacitors and secondary batteries.
1. An electronic thermal management article comprising at least one sheet of resin impregnated, compressed particles of exfoliated graphite cured by the simultaneous application of pressure of at least 7 MPa and a temperature sufficient to cure the resin, wherein the article exhibits a thermal conductivity which is anisotropic in nature and is greater than about 300 W/mK in at least one plane.
2. The article of claim 1 wherein the graphite sheet is simultaneously cured at a temperature of at least about 90° C. and at a pressure of at least about 7 MPa.
3. The article of claim 1 wherein the anisotropic thermal conductivity varies by a factor of at least 15 as between a plane with a higher thermal conductivity and a plane with lower thermal conductivity.
4. The device of claim 1 wherein the pressure cured graphite sheet has a density greater than about 1.85 g/cm3.
5. The article of claim 1 wherein the sheet of graphite has a resin content of at least about 3% by weight.
6. The article of claim 5 wherein the sheet of graphite has a resin content of from about 5% to about 35% by weight.
7. An anisotropic electronic thermal management article having a thermal conductivity of greater than about 300 W/mK in an in plane direction and a thermal conductivity of less than about 15 W/mK in an out of plane direction and comprising at least one resin impregnated sheet of compressed particles of exfoliated graphite cured by the simultaneous appllication of pressure of at least 7 MPa and a temperature sufficient to cure the resin.
8. The article of claim 7 wherein the resin is epoxy.
9. The device of claim 7 wherein the resin impregnated sheet has a density of at least about 1.85 g/cm3.
10. The article of claim 7 wherein the graphite sheet is simultaneously cured at a temperature of at least about 90° C. and at a pressure of at least about 7 MPa.