Reversible Tailoring of Mechanical Properties of Carbon Nanotube Forests by Immersing in Solvents
Abstract
The mechanical behavior of carbon nanotube (CNT) forests soaked in three solvents toluene, acetonitrile, and isopropanol is examined. Effective stiffness of the structure is evaluated in the dry and wet condition by micro-indentation using a 100 lm flat punch. With soaking of CNT forests in solvents, the stiffness decreases and deformation mechanism changes from buckling concentrated close to the bottom of the CNT forest to a distribution of local buckles along the height and global buckling of the entire length of CNTs. We use molecular dynamics simulations to relate the experimental observations to the reduced mechanical support from neighbor CNTs due to a decreased magnitude of van derWaals (vdW) interactions in the presence of solvents. Toluene, which produces the lowest average measured stiffness between the three solvents, produces the lowest vdW forces between individual CNTs. Furthermore, wet-dry cycling of CNT forests shows the reversibility and repeatability of change of stiffness by immersing in solvents. The results show that soaking CNT forests in solvents could be useful for applications such as interface materials where lower stiffness of CNT forests are needed and applications such as energy absorbing materials in which re-setting of stiffness is required.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 07, 2014
- Accession Number
- ADA600900
Entities
People
- Baratunde A. Cola
- Jeffery W Baur
- Matthew R Maschmann
- Parisa P. Abadi
- S. M. Mortuza
- Samuel Graham
- Soumik Banerjee
Organizations
- Air Force Research Laboratory