Practical PBT/PC/GNP composites with anisotropic thermal conductivity

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• High thermal conductivity polymer composites are crucial for industrial applications.
• Current materials often face limitations hindering direct industrial adoption.
• Developing cost-effective and high-performance composites remains a key challenge.

Purpose of the Study:

• To develop a practical polybutylene terephthalate (PBT)/polycarbonate (PC)/graphite nanoplatelet (GNP) thermally conductive composite.
• To investigate the effect of graphite nanoplatelet (GNP) content on composite performance.
• To achieve enhanced thermal conductivity, heat resistance, and mechanical properties at low filler content.

Main Methods:

• Conventional melt-blending technique used for composite preparation.
• Selective distribution and orientation of graphite nanoplatelets (GNPs) within the PBT phase.
• Characterization of thermal conductivity, heat resistance (Vicat softening temperature), and mechanical properties.

Main Results:

• A PBT/PC/GNP composite with 20 vol% GNPs demonstrated superior performance.
• In-plane thermal conductivity increased by 2430% (5.82 W m^-1 K^-1) and through-plane by 361% (1.06 W m^-1 K^-1) compared to neat PBT/PC.
• Vicat softening temperature increased by 17.7 °C to 213.7 °C, with maintained mechanical properties.

Conclusions:

• The developed PBT/PC/GNP composite offers a practical solution for industrial applications requiring high thermal conductivity.
• Selective GNP distribution and orientation lead to a low percolation threshold and anisotropic thermal conductivity.
• The composite exhibits an excellent balance of thermal, heat resistance, and mechanical properties suitable for demanding applications.