Self-Healable Conductive Glassy Polymer Composites for Bluetooth Antenna Applications

Carbon nanotubes (CNTs) are promising conductive nanofillers for functional polymer composites. However, polymers capable of effectively dispersing CNTs are often highly specialized, and surface modification of CNTs is commonly required to improve their compatibility with polymer matrices. Such modification can disrupt the intrinsic CNT structure and consequently compromise their mechanical and electrical properties.
Here, we report that poly(ether thiourea), a glassy polymer previously developed by our group and capable of self-healing even below its glass-transition temperature[1], enables the homogeneous dispersion of pristine CNTs at high concentrations without surface modification. The resulting composites retain the intrinsic self-healing ability of the polymer while simultaneously exhibiting high electrical conductivity, enhanced mechanical robustness, and hydrophobicity.
Leveraging their excellent CNT dispersibility, processability, electrical conductivity, mechanical properties, and self-healing capability, the composites were fabricated into 2.4 GHz Bluetooth antennas. The antennas exhibited stable wireless communication performance, and their radiation characteristics, which deteriorated substantially after mechanical damage, were restored following room-temperature self-healing. These results demonstrate the potential of the composites as multifunctional materials for self-healable electronic applications.

[1] Yanagisawa, Y.; Nan, Y.; Okuro, K.; Aida, T. Science 2018, 359, 72.