Table of Contents
Smart Materials Research
Volume 2015 (2015), Article ID 248490, 8 pages
http://dx.doi.org/10.1155/2015/248490
Research Article

Microwave Assisted Healing of Thermally Mendable Composites

1ERC, Houston, TX 77058, USA
2NanoComposix, San Diego, CA 92111, USA
3NASA Johnson Space Center, Houston, TX 77058, USA

Received 19 September 2014; Accepted 14 January 2015

Academic Editor: Kelvin Yeung

Copyright © 2015 Edward D. Sosa et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Polymer matrix composites offer high specific strength; however, their potential weight savings have been limited by the concern of damage tolerance. If microcracking and similar incurred damage could be autonomously sealed, composite structures could be built thinner and lighter while still addressing damage tolerance, thus achieving the weight savings they promise. Various self-healing mechanisms have been proposed to this end. Herein, a method of thermally reversible polymerization is investigated. To date, thermally activated repair of composites have been accomplished typically through resistive heating, which has certain inherent complexities. An alternate heating method, via microwave exposure of carbon nanotubes incorporated throughout a thermal reversible polymer matrix, is demonstrated. Carbon nanotube-doped composites exhibit enhanced microwave absorption over an undoped control sample. Furthermore, it is shown that these composites can be heated locally by a focused microwave source. The particular composite formulation and layup studied could be uniformly heated to the targeted healing temperature of 100°C in as little as 20 seconds, followed by a healing time on the scale of minutes with total time depending upon the extent of damage.