High-Speed Surfactant-Free Fabrication of Large Carbon Nanotube Membranes for Multifunctional Composites

Abstract

A high-speed manufacturing process for multiwalled carbon nanotube (MWNT) buckypaper is presented, and its application as an embedded strain sensor for composite materials is demonstrated. This manufacturing method enables the production of sizable carbon nanotube (CNT) membranes with significantly reduced processing time and less manufacturing complexity than other contemporary techniques. The use of surfactants and chemical functionalization of MWNTs was completely avoided in this method because functionality of carbon nanotubes can be hampered by such surface treatments. Microstructure, mechanical properties, and piezoresistive response of the fabricated buckypaper were characterized, and its sensitivity as a strain sensor was analyzed. Stable piezoresistive response could be achieved at low strains, and a high sensitivity to strain was observed when buckypaper was embedded in glass fiber epoxy laminates for strain sensing.