Functionalizing CNTs for Making Epoxy/CNT Composites
- Tuesday, 25 August 2009
Functionalization of carbon nanotubes (CNTs) with linear molecular side chains of polyphenylene ether (PPE) has been shown to be effective in solubilizing the CNTs in the solvent components of solutions that are cast to make epoxy/CNT composite films. (In the absence of solubilization, the CNTs tend to clump together instead of becoming dispersed in solution as needed to impart, to the films, the desired CNT properties of electrical conductivity and mechanical strength.) Because the PPE functionalizes the CNTs in a non-covalent manner, the functionalization does not damage the CNTs. The functionalization can also be exploited to improve the interactions between CNTs and epoxy matrices to enhance the properties of the resulting composite films.
In addition to the CNTs, solvent, epoxy resin, epoxy hardener, and PPE, a properly formulated solution also includes a small amount of polycarbonate, which serves to fill voids that, if allowed to remain, would degrade the performance of the film. To form the film, the solution is drop-cast or spin-cast, then the solvent is allowed to evaporate.
This work was done by Jian Chen and Ramasubramaniam Rajagopal of Zyvex Corp. for Johnson Space Center. For further information, contact the Johnson Commercial Technology Office at (281) 483-3809.
In accordance with Public Law 96-517, the contractor has elected to retain title to this invention. Inquiries concerning rights for its commercial use should be addressed to:
1321 North Plano Rd.
Richardson TX 75081-2426
Web Address: http://www.zyvex.com
Refer to MSC-23719-1, volume and number of this NASA Tech Briefs issue, and the page number.