Researchers from University of California - Riverside (UCR) report that compressed graphene laminate on PET achieve a higher thermal conductivity compared to non-compressed laminates (for the same average flake size). This is due to better flake alignment.

Graphene has a very high thermal conductivity. At room temperature, a graphene sheet has thermal conductivity of 2000 W/mk to 50000 W/mk. When you place it on a substrate the conductivity is lowered substantially (to around 90 W/mk) - but it is still substantially better than that of plastics.

The researchers found that that the average size and the alignment of graphene flakes are more important parameters defining the heat conduction than the mass density of the graphene laminate. This was an unexpected result. The team also discovered that the thermal conductivity scales up linearly with the average graphene flake size in both uncompressed and compressed laminates.