Modified graphene/polyimide composite films with strongly enhanced thermal conductivity

Area of Science:

• Materials Science
• Nanotechnology
• Composite Materials

Background:

• Efficient thermal management is crucial for portable electronics.
• Existing materials often lack the required combination of flexibility and thermal conductivity.
• Graphene-based materials show promise but require improved fabrication methods.

Purpose of the Study:

• To develop a flexible film with superior thermal conductivity for electronic thermal management.
• To enhance the in-plane thermal conductivity of graphene films using a novel fabrication method.
• To demonstrate the flexibility and durability of the developed composite film.

Main Methods:

• Modification of graphene oxide (GO) with 4,4'-diaminodiphenyl ether (ODA) via covalent bonding.
• In situ "modified-welding" using intercalated polyimide (PI) to join GO sheets.
• Graphitization of the modified graphene/polyimide composite film (g-mGO/PI).

Main Results:

• Achieved a superior in-plane thermal conductivity of 1352 ± 5 W m-1 K-1 for the g-mGO/PI film.
• Demonstrated a 92.3% increase in thermal conductivity compared to pristine graphitized graphene film (g-GO).
• The g-mGO/PI film exhibited excellent flexibility, surviving 2000-cycle anti-bending tests.

Conclusions:

• The "modified-welding" strategy effectively enhances the thermal conductivity and flexibility of graphene-based films.
• This method offers an innovative approach for developing advanced materials for thermal management in electronics.
• The resulting composite films are suitable for demanding applications requiring high thermal performance and durability.