Mass Preparation Of Graphene Based Heat Dissipating Composites

Poor heat dissipation has always been one of the essential problems leading to the failure of electronic elements.The rapid development of electronic devices such as CPU and LED is tending to higher power and integration,which has raised a big challenge to the heat dissipation.Poor heat dissipation leads to a rise in working temperature,resulting in a shortened working life or malfunction,and even risking the probability of causing production accident.In that case,the study of better heat dissipation technique would be very important to support a stable operation of the new generation of electronic devices.This thesis,focusing on the demand on heat dissipation for high power LED road lamps,explores a composite material comprised of graphene and polymer for LED heatsink.Based on the current problem of the commercial aluminum based heatsink,the thesis develops well performed,stable and low cost graphene based thermally conductive plastics and paints,and proposes an integrated heat dissipation solution combining thermally conductive plastics and coating as a promising substitution of aluminum heatsink.The main contents of this thesis are as follows:(1)Two processes for mass production of graphene and graphene oxide were developed.The purification of graphene oxide via Hummers method had been industrially optimized.Also,a few layers of graphene suitable for thermally conductive application were prepared by mechanical grinding method.(2)An integrated heat dissipation solution including graphene based thermally conductive plastics and paints were proposed for LED heat dissipation,the mass production of which,based on graphene oxide and few-layered graphene,was simple process,low cost,stable and environmentally friendly.(3)The integrated heat dissipation combined of graphene based thermally conductive plastics and coating was practically applied to LED road lamps.The graphene based thermally conductive plastics exhibited comparably effective heat dissipation ability for the application of LED road lamps.Furthermore,the coating of graphene based paints can further increase the heat dissipation performance on both thermally conductive plastics and aluminum heatsink.Generally,this thesis,aiming at the demand on heat dissipation of LED road lamps,has developed an integrated and industrially available technique from raw materials to products and from thermally conductive plastics to coating.