Carbon Nanotubes Decorated with Silver Nanoparticles for Flexible Conductive Adhesives

R. Ma, S. Kwon, Q. Zheng, H.Y. Kwon, J.I. Kim, H.R. Choi and S. Baik
Sungkyunkwan University, KR

Keywords: flexible electronics, conductive adhesives, silver, carbon nanotubes, oxidation resistance

Summary:

Carbon nanotube-incorporated polymer matrix composites with high conductivity have been of interests for decades due to the excellent mechanical/electrical properties and high aspect ratio of nanotubes. However, the contact resistance was recognized as one of the impeding factors to realize high conductivity. Here we employ the strategy with nitrile butadiene rubber as a matrix material to develop flexible conductive adhesives. The flexible nanotubes with high aspect ratios constructed effective electrical networks between micron-scale Ag powders, and the silver nanoparticles adsorbed on the sidewalls of nanotubes enhanced the contact interface. A maximum conductivity of 37521 S/cm was achieved, and the normalized resistance change was smaller than 3.5% when the specimen was bent to a radius of 4.5 mm. The conductivity after 3000 bending cycles was 10764 S/cm. The surface after curing was hydrophobic demonstrating excellent oxidation resistance. The adhesion on poly(ethylene terephthalate) and transparent conductive films was also good. This novel adhesive with high conductivity, flexibility, cyclability, oxidation resistance, and good adhesion may enable facile incorporation of silicon islands for flexible electronic devices.