Facile Method to Fabricate Highly Thermally Conductive Graphite/PP Composite with Network Structures.

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Thermally conductive polymer composites are crucial for various industrial applications.
• Developing efficient and scalable fabrication methods remains a key challenge.
• Graphite is a promising filler due to its high intrinsic thermal conductivity.

Purpose of the Study:

• To introduce a novel fabrication method for graphite/polypropylene (PP) composites.
• To achieve high thermal conductivity in these composites through network formation.
• To investigate the relationship between microstructure and thermal performance.

Main Methods:

• Fabrication of graphite/polypropylene (PP) composites using a novel method.
• Characterization of the composite's microstructure, focusing on graphite flake orientation.
• Measurement of the thermal conductivity coefficient.
• Application of the Hashin-Shtrikman (HS) model for theoretical interpretation.

Main Results:

• A continuous thermally conductive network of graphite flakes was successfully constructed within the PP matrix.
• The thermal conductivity coefficient reached 5.4 W/mK at 21.2 vol % graphite loading.
• Orientations of crystalline graphite flakes around PP resin particles contributed to the enhanced conductivity.
• The Hashin-Shtrikman model effectively explained the observed thermal properties.

Conclusions:

• The novel fabrication method enables the creation of graphite/PP composites with significantly improved thermal conductivity.
• The formation of a well-defined graphite network is critical for achieving high thermal performance.
• This study offers a valuable guideline for fabricating thermally conductive composites with network structures.