Thermo-physical responses of polymeric composites tailored by electric field

Applying an electric field to a liquid suspension redistributes the inclusions, arranges them in chain-like structures and/or orients fibrous inclusions or chain-like structures parallel to electric field. The present paper shows micro-tailored polymer composites including orthotropic structures and describes physical mechanisms influencing the microstructure in an electric field. Mechanical and thermal properties of orthotropic and random composites containing glass-fiber or graphite particles in an epoxy are measured. Both the glass-fiber and graphite chains in epoxy response mechanically as one would anticipate for orthotropic materials. However, while thermal expansion response of the aligned glass–epoxy composite is orthotropic, that of the aligned graphite composite is essentially isotropic. Thermal expansion, thermal conduction, and optical property of tailored graphite–epoxy composites are tested for various compositions, orientation directions of contacted particles’ chains.